Sample records for nagano prefecture earthquake

  1. Anomalously high radon discharge from the atotsugawa fault prior to the western nagano prefecture earthquake ( m 6.8) of september 14, 1984

    NASA Astrophysics Data System (ADS)

    ui, Hirotaka; Moriuchi, Hiroyuki; Takemura, Yukiko; Tsuchida, Hiroko; Fujii, Iwao; Nakamura, Masaru

    1988-09-01

    Radon alpha tracks monitored at six sites increased gradually three months before (detected by microscopic counting), and increased remarkably 2 weeks before (detected by both mechanical and microscopic counting) the western Nagano Prefecture earthquake ( M 6.8) which occurred on September 14, 1984. The monitoring sites were located about 65 km northwest of the epicenter, on the shear zone of the Atotsugawa fault. The changes in radon emanation are considered to be related to the earthquake rather than to changes in meteorological conditions.

  2. Aftershock distribution and heterogeneous structure in and around the source area of the 2014 northern Nagano Prefecture earthquake (Mw 6.2) , central Japan, revealed by dense seismic array observation

    NASA Astrophysics Data System (ADS)

    Kurashimo, E.; Hirata, N.; Iwasaki, T.; Sakai, S.; Obara, K.; Ishiyama, T.; Sato, H.

    2015-12-01

    A shallow earthquake (Mw 6.2) occurred on November 22 in the northern Nagano Prefecture, central Japan. Aftershock area is located near the Kamishiro fault, which is a part of the Itoigawa-Shizuoka Tectonic Line (ISTL). ISTL is one of the major tectonic boundaries in Japan. Precise aftershock distribution and heterogeneous structure in and around the source region of this earthquake is important to constrain the process of earthquake occurrence. We conducted a high-density seismic array observation in and around source area to investigate aftershock distribution and crustal structure. One hundred sixty-three seismic stations, approximately 1 km apart, were deployed during the period from December 3, 2014 to December 21, 2014. Each seismograph consisted of a 4.5 Hz 3-component seismometer and a digital data recorder (GSX-3). Furthermore, the seismic data at 40 permanent stations were incorporated in our analysis. During the seismic array observation, the Japan Meteorological Agency located 977 earthquakes in a latitude range of 35.5°-37.1°N and a longitude range of 136.7°-139.0°E, from which we selected 500 local events distributed uniformly in the study area. To investigate the aftershock distribution and the crustal structure, the double-difference tomography method [Zhang and Thurber, 2003] was applied to the P- and S-wave arrival time data obtained from 500 local earthquakes. The relocated aftershock distribution shows a concentration on a plane dipping eastward in the vicinity of the mainshock hypocenter. The large slip region (asperity) estimated from InSAR analysis [GSI, 2014] corresponds to the low-activity region of the aftershocks. The depth section of Vp structure shows that the high Vp zone corresponds to the large slip region. These results suggest that structural heterogeneities in and around the fault plane may have controlled the rupture process of the 2014 northern Nagano Prefecture earthquake.

  3. Complementary Ruptures of Surface Ruptures and Deep Asperity during the 2014 Northern Nagano, Japan, Earthquake (MW 6.3)

    NASA Astrophysics Data System (ADS)

    Asano, K.; Iwata, T.; Kubo, H.

    2015-12-01

    A thrust earthquake of MW 6.3 occurred along the northern part of the Itoigawa-Shizuoka Tectonic Line (ISTL) in the northern Nagano prefecture, central Japan, on November 22, 2014. This event was reported to be related to an active fault, the Kamishiro fault belonging to the ISTL (e.g., HERP, 2014). The surface rupture is observed along the Kamishiro fault (e.g., Lin et al., 2015; Okada et al., 2015). We estimated the kinematic source rupture process of this earthquake through the multiple time-window linear waveform inversion method (Hartzell and Heaton, 1983). We used velocity waveforms in 0.05-1 Hz from 12 strong motion stations of K-NET, KiK-net (NIED), JMA, and Nagano prefecture (SK-net, ERI). In order to enhance the reliability in Green's functions, we assumed one-dimensional velocity structure models different for the different stations, which were extracted from the nation-wide three-dimensional velocity structure model, Japan Integrated Velocity Structure Model (JIVSM, Koketsu et al., 2012). Considering the spatial distribution of aftershocks (Sakai et al., 2015) and surface ruptures, the assumed fault model consisted of two dip-bending fault segments with different dip angles between the northern and southern segments. The total length and width of the fault plane is 20 km and 13 km, relatively, and the fault model is divided into 260 subfaults of 1 km × 1 km in space and six smoothed ramp functions in time. An asperity or large slip area with a peak slip of 1.9 m was estimated in the lower plane of the northern segment in the approximate depth range of 4 to 8 km. The depth extent of this asperity is consistent with the seismogenic zone revealed by past studies (e.g., Panayotopoulos et al., 2014). In contrast, the slip in the southern segment is relatively concentrated in the shallow portion of the segment where the surface ruptures were found along the Kamishiro fault. The overall spatial rupture pattern of the source fault, in which the deep asperity

  4. Bath water contamination with Legionella and nontuberculous mycobacteria in 24-hour home baths, hot springs, and public bathhouses of Nagano Prefecture, Japan.

    PubMed

    Kobayashi, Michiko; Oana, Kozue; Kawakami, Yoshiyuki

    2014-01-01

    Bath water samples were collected from 116 hot springs, 197 public bathhouses, and 38 24-hour home baths in Nagano Prefecture, Japan, during the period of April 2009 to November 2011, for determining the presence and extent of contamination with Legionella and nontuberculous mycobacteria. Cultures positive for Legionella were observed in 123 of the 3,314 bath water samples examined. The distribution and abundance of Legionella and/or combined contamination with Legionella and nontuberculous mycobacteria were investigated to clarify the contamination levels. The abundance of Legionella was demonstrated to correlate considerably with the levels of combined contamination with Legionella and nontuberculous mycobacteria. Legionella spp. were obtained from 61% of the water samples from 24-hour home baths, but only from 3% of the samples from public bathhouses and hot springs. This is despite the fact that a few outbreaks of Legionnaires' disease in Nagano Prefecture as well as other regions of Japan have been traced to bath water contamination. The comparatively higher rate of contamination of the 24-hour home baths is a matter of concern. It is therefore advisable to routinely implement good maintenance of the water basins, particularly of the 24-hour home baths.

  5. ANALYSIS FOR HOUSE DAMAGE PROPERTY OF 2007 MID-NIIGATA PREFECTURE OFFSHORE EARTHQUAKE

    NASA Astrophysics Data System (ADS)

    Ochiai, Hirokazu; Yamada, Kento; Ohtsuka, Satoru; Isobe, Koichi

    This paper reports the result of correlation analysis for house damage in 2007 Mid-piigata prefecture offshore earthquake by focusing geomorphological land classification and other factors as landform and ground properties with organizing the house damage data of disaster victim certificate conducted by public administrations. In former part of the paper, the features of house damage at 2007 Mid-Niigata prefecture offshore earthquake were analyzed for various influencing factors. The authors discussed the affrecting factors to houses at earthquake. In latter part, the features of house damage at 2007 Mid-Niigata prefecture offshore earthquake was discussed with that at 2004 Mid-Niigata prefecture earthquake. The house damage function of distance from the epicenter was proposed based on the analysis on house damage ratio recorded in two earthquakes.

  6. Estimation of seismic velocity changes at different depths associated with the 2014 Northern Nagano Prefecture earthquake, Japan ( M W 6.2) by joint interferometric analysis of NIED Hi-net and KiK-net records

    NASA Astrophysics Data System (ADS)

    Sawazaki, Kaoru; Saito, Tatsuhiko; Ueno, Tomotake; Shiomi, Katsuhiko

    2016-12-01

    To estimate the seismic velocity changes at different depths associated with a large earthquake, we apply passive image interferometry to two types of seismograms: KiK-net vertical pairs of earthquake records and Hi-net continuous borehole data. We compute the surface/borehole deconvolution waveform (DCW) of seismograms recorded by a KiK-net station and the autocorrelation function (ACF) of ambient noise recorded by a collocated Hi-net station, 26 km from the epicenter of the 2014 Northern Nagano Prefecture earthquake, Japan ( M W 6.2). Because the deeper KiK-net sensor and the Hi-net sensor are collocated at 150 m depth, and another KiK-net sensor is located at the surface directly above the borehole sensors, we can measure shallow (<150 m depth) and deep (>150 m depth) velocity changes separately. The sensitivity of the ACF to the velocity changes in the deeper zone is evaluated by a numerical wave propagation simulation. We detect relative velocity changes of -3.1 and -1.4% in the shallow and deep zones, respectively, within 1 week of the mainshock. The relative velocity changes recover to -1.9 and -1.1%, respectively, during the period between 1 week and 4 months after the mainshock. The observed relative velocity reductions can be attributed to dynamic strain changes due to the strong ground motion, rather than static strain changes due to coseismic deformation by the mainshock. The speed of velocity recovery may be faster in the shallow zone than in the deep zone because the recovery speed is controlled by initial damage in the medium. This recovery feature is analogous to the behavior of slow dynamics observed in rock experiments.

  7. Evaluation of the Monkey-Persimmon Environmental Education Program for Reducing Human-Wildlife Conflicts in Nagano, Japan

    ERIC Educational Resources Information Center

    Sakurai, Ryo; Jacobson, Susan K.

    2011-01-01

    Co-existing with wildlife and maintaining rural livelihoods are common challenges in remote villages in Japan. The authors assess the effects of the Monkey-Persimmon Environmental Education Program developed to reduce wildlife conflicts and to revitalize a community in Nagano Prefecture. Development of a logic model helped guide interviews with…

  8. First fossil occurrence of a filefish (Tetraodontiformes; Monacanthidae) in Asia, from the Middle Miocene in Nagano Prefecture, central Japan.

    PubMed

    Miyajima, Yusuke; Koike, Hakuichi; Matsuoka, Hiroshige

    2014-04-10

    A new fossil filefish, Aluterus shigensis sp. nov., with a close resemblance to the extant Aluterus scriptus (Osbeck), is described from the Middle Miocene Bessho Formation in Nagano Prefecture, central Japan. It is characterized by: 21 total vertebrae; very slender and long first dorsal spine with tiny anterior barbs; thin and lancet-shaped basal pterygiophore of the spiny dorsal fin, with its ventral margin separated from the skull; proximal tip of moderately slender first pterygiophore of the soft dorsal fin not reaching far ventrally; soft dorsal-fin base longer than anal-fin base; caudal peduncle having nearly equal depth and length; and tiny, fine scales with slender, straight spinules. The occurrence of this fossil filefish from the Bessho Formation is consistent with the influence of warm water currents suggested by other fossils, but it is inconsistent with the deep-water sedimentary environment of this Formation. This is the first fossil occurrence of a filefish in Asia; previously described fossil filefishes are known from the Pliocene and Pleistocene of Italy, the Pliocene of Greece, and the Miocene and Pliocene of North America. These fossil records suggest that the genus Aluterus had already been derived and was widely distributed during the Middle Miocene with taxa closely resembling Recent species.

  9. Helicobacter pylori infection and its related factors in junior high school students in Nagano Prefecture, Japan.

    PubMed

    Nakayama, Yoshiko; Lin, Yingsong; Hongo, Minoru; Hidaka, Hiroya; Kikuchi, Shogo

    2017-04-01

    There have been few reports on Helicobacter pylori (H. pylori) infection in asymptomatic Japanese children and adolescents. We hypothesized that the prevalence of H. pylori infection is very low among Japanese children and that clinical variables such as serum pepsinogen and iron levels are associated with H. pylori infection. We conducted a cross-sectional analysis of a sample of 454 junior high school students aged 12-15 years in four areas in Nagano Prefecture. A commercial ELISA kit (E-plate Eiken H. pylori antibody) was used to measure IgG antibody against H. pylori. Serum pepsinogen and iron levels were also measured using standard methods. A urea breath test was performed for seropositive students. The overall prevalence of H. pylori was 3.1% (14/454). There were no significant differences in H. pylori prevalence among mountain, rural, and urban areas. The mean level of both serum pepsinogen (PG I) and PG II was significantly increased in the seropositive subjects compared with the seronegative subjects. When the cutoff values for adults (PG I: 70 ng/mL and PG I/II ratio: 3) were used, 4 of 14 subjects had PG I ≤70 ng/mL and PG I/II ratio ≤3. The results of a logistic regression analysis showed that low serum iron levels were significantly associated with H. pylori infection (P=.02). The prevalence of H. pylori infection is as low as 3% among junior high school students aged 12-15 years in Japan. The disappearance of H. pylori is accelerating in Japanese children. © 2016 John Wiley & Sons Ltd.

  10. Source parameters and rupture velocities of microearthquakes in western Nagano, Japan, determined using stopping phases

    USGS Publications Warehouse

    Imanishi, K.; Takeo, M.; Ellsworth, W.L.; Ito, H.; Matsuzawa, T.; Kuwahara, Y.; Iio, Y.; Horiuchi, S.; Ohmi, S.

    2004-01-01

    We use an inversion method based on stopping phases (Imanishi and Takeo, 2002) to estimate the source dimension, ellipticity, and rupture velocity of microearthquakes and investigate the scaling relationships between source parameters. We studied 25 earthquakes, ranging in size from M 1.3 to M 2.7, that occurred between May and August 1999 at the western Nagano prefecture, Japan, which is characterized by a high rate of shallow earthquakes. The data consist of seismograms recorded in an 800-m borehole and at 46 surface and 2 shallow borehole seismic stations whose spacing is a few kilometers. These data were recorded with a sampling frequency of 10 kHz. In particular, the 800-m-borehole data provide a wide frequency bandwidth with greatly reduced ground noise and coda wave amplitudes compared with surface recordings. High-frequency stopping phases appear in the body waves in Hilbert transform pairs and are readily detected on seismograms recorded in the 800-m borehole. After correcting both borehole and surface data for attenuation, we also measure the rise time, which is defined as the interval from the arrival time of the direct wave to the timing of the maximum amplitude in the displacement pulse. The differential time of the stopping phases and the rise times were used to obtain source parameters. We found that several microearthquakes propagated unilaterally, suggesting that all microearthquakes cannot be modeled as a simple circular crack model. Static stress drops range from approximately 0.1 to 2 MPa and do not vary with seismic moment. It seems that the breakdown in stress drop scaling seen in previous studies using surface data is simply an artifact of attenuation in the crust. The average value of rupture velocity does not depend on earthquake size and is similar to those reported for moderate and large earthquakes. It is likely that earthquakes are self-similar over a wide range of earthquake size and that the dynamics of small and large earthquakes are

  11. Resources for business continuity in disaster-based hospitals in the great East Japan earthquake: survey of Miyagi Prefecture disaster base hospitals and the prefectural disaster medicine headquarters.

    PubMed

    Kudo, Daisuke; Furukawa, Hajime; Nakagawa, Atsuhiro; Yamanouchi, Satoshi; Koido, Yuichi; Matsumura, Takashi; Abe, Yoshiko; Konishi, Ryota; Matoba, Masaaki; Tominaga, Teiji; Kushimoto, Shigeki

    2013-10-01

    To clarify advance measures for business continuity taken by disaster base hospitals involved in the Great East Japan Earthquake. The predisaster situation regarding stockpiles was abstracted from a 2010 survey. Timing of electricity and water restoration and sufficiency of supplies to continue operations were investigated through materials from Miyagi Prefecture disaster medicine headquarters (prefectural medical headquarters) and disaster base hospitals (14 hospitals) in Miyagi Prefecture after the East Japan earthquake. The number of hospitals with less than 1 day of stockpiles in reserve before the disaster was 7 (50%) for electricity supplies, 8 (57.1%) for water, 6 (42.9%) for medical goods, and 6 (42.9%) for food. After the disaster, restoration of electricity and water did not occur until the second day or later at 8 of 13 (61.5%) hospitals, respectively. By the fourth postdisaster day, 14 hospitals had requested supplies from the prefectural medical headquarters: 9 (64.3%) for electricity supplies, 2 (14.3%) for water trucks, 9 (64.3%) for medical goods, and 6 (42.9%) for food. The lack of supplies needed to continue operations in disaster base hospitals following the disaster clearly indicated that current business continuity plans require revision.

  12. The 2011 Great East Japan earthquake: a report of a regional hospital in Fukushima Prefecture coping with the Fukushima nuclear disaster.

    PubMed

    Irisawa, Atsushi

    2012-05-01

    A catastrophic undersea megathrust earthquake of magnitude 9.0 off the coast of Japan occurred at 14:46 JST on Friday, 11 March 2011. The earthquake triggered powerful tsunami waves, and the tsunami precipitated Fukushima nuclear accidents. After the terrible earthquake, many people fled from the nuclear accident and arrived at places far from the nuclear power plant. In this article, I present a story of one measure devised to deal with the problem of the Fukushima nuclear accident at a regional hospital of Fukushima prefecture, Aizu General Hospital, which is located far from the Fukushima nuclear plant. In addition, I briefly report the current situation of Fukushima prefecture after the 2011 Great East Japan earthquake. In our hospital, the countermeasure headquarters was established to supply medical care for those who had been injured by tsunami waves and the Fukushima nuclear accident. Especially, the screening for radioactive exposure using a dosimeter to take decontamination measures for cases of external exposure was extremely important task. Nevertheless, because the accurate knowledge related to radioactive contamination didn't provide, most medical staff fell into confusion. Fukushima prefecture has been 'shrinking' since the nuclear accident. However, today, although some hot spots remain in residential areas, the radioactive contamination is decreasing little by little. Many people in Fukushima Prefecture advance as one, facing forward. Recently, decontamination projects started. Efforts must be continued over a long period. © 2012 The Author. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  13. Earthquake Preparedness Among Japanese Hemodialysis Patients in Prefectures Heavily Damaged by the 2011 Great East Japan Earthquake.

    PubMed

    Sugisawa, Hidehiro; Shimizu, Yumiko; Kumagai, Tamaki; Sugisaki, Hiroaki; Ohira, Seiji; Shinoda, Toshio

    2017-08-01

    The purpose of this study was to explore the factors related to earthquake preparedness in Japanese hemodialysis patients. We focused on three aspects of the related factors: health condition factors, social factors, and the experience of disasters. A mail survey of all the members of the Japan Association of Kidney Disease Patients in three Japanese prefectures (N = 4085) was conducted in March, 2013. We obtained 1841 valid responses for analysis. The health factors covered were: activities of daily living (ADL), mental distress, primary renal diseases, and the duration of dialysis. The social factors were: socioeconomic status, family structure, informational social support, and the provision of information regarding earthquake preparedness from dialysis facilities. The results show that the average percentage of participants that had met each criterion of earthquake preparedness in 2013 was 53%. Hemodialysis patients without disabled ADL, without mental distress, and requiring longer periods of dialysis, were likely to meet more of the earthquake preparedness criteria. Hemodialysis patients who had received informational social support from family or friends, had lived with spouse and children in comparison to living alone, and had obtained information regarding earthquake preparedness from dialysis facilities, were also likely to meet more of the earthquake preparedness criteria. © 2017 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

  14. Supports for libraries'restoration from the Great East Japan Earthquake : Challenges we address at Miyagi Prefectural Library

    NASA Astrophysics Data System (ADS)

    Kumagai, Shinichiro

    This article overviews the situations of damage and reconstruction of mainly public libraries in Miyagi Prefecture about 9 months after the Great East Japan Earthquake. Serious damage of library buildings was due not only to the tsunami or seismic sea wave but to violent shaking, the latter less reported by the media. We at the Miyagi Prefectural Library implemented reconstruction assistance for regional public libraries in both direct and indirect ways. Among them, we report in detail on the support we offered until the Minami-sanriku Town Library reopened its service. We highlight a prefectural library's role, acting between supporters and those supportees, to consider the necessity of middle organizations. We clarify what challenges we face and examine how best to provide assistance in case of large-scale disasters.

  15. Incidence of Domestic Violence Against Pregnant Females After the Great East Japan Earthquake in Miyagi Prefecture: The Japan Environment and Children's Study.

    PubMed

    Sakurai, Kasumi; Nishigori, Hidekazu; Nishigori, Toshie; Mizuno, Satoshi; Obara, Taku; Iwama, Noriyuki; Watanabe, Zen; Ishikuro, Mami; Tatsuta, Nozomi; Nishijima, Ichiko; Sugawara, Junichi; Fujiwara, Ikuma; Arima, Takahiro; Kuriyama, Shinichi; Metoki, Hirohito; Takahashi, Fumiaki; Nakai, Kunihiko; Yaegashi, Nobuo

    2017-04-01

    This study aimed to clarify the correlation between the 2011 Great East Japan Earthquake and domestic violence (DV) against pregnant females after the disaster in Miyagi Prefecture, an area damaged by the earthquake and tsunami. We analyzed 7600 pregnant females from June to December 2011. The incidence of physical and mental DV and the proportions in the inland, north coastal, and south coastal areas of Miyagi Prefecture and nationwide were calculated, and a chi-square test was conducted for comparison. The risk factors for DV were estimated with multivariate logistic regression analyses on a prefecture-wide basis. The incidence levels for physical DV were found to be 5.9% in the north coastal area, which was significantly higher than in the inland area (1.3%, P=0.0007) and nationwide (1.5%, P<0.0001). There were no significant differences in the incidence of mental DV between the 3 areas in Miyagi Prefecture (inland 15.2%, north coast 15.7%, and south coast 18.8%) or nationwide (13.8%). Experiencing disease or injury in someone close and changes in the family structure were significantly associated with mental DV in Miyagi Prefecture. Continuous monitoring and support for pregnant females may be necessary to address this issue in disaster-affected areas. (Disaster Med Public Health Preparedness. 2017;11:216-226).

  16. Peptic Ulcers in Fukushima Prefecture Related to the Great East Japan Earthquake, Tsunami and Nuclear Accident

    PubMed Central

    Hikichi, Takuto; Sato, Masaki; Watanabe, Ko; Nakamura, Jun; Kikuchi, Hitomi; Ejiri, Yutaka; Ishihata, Ryoichi; Irisawa, Atsushi; Takahashi, Yuta; Saito, Hironobu; Takagi, Tadayuki; Suzuki, Rei; Sugimoto, Mitsuru; Konno, Naoki; Waragai, Yuichi; Asama, Hiroyuki; Takasumi, Mika; Sato, Yuki; Ohira, Hiromasa; Obara, Katsutoshi

    2017-01-01

    Objective Due to the Great East Japan Earthquake, which occurred in March 2011, many residents of Fukushima Prefecture were affected by a radiation accident in addition to suffering loss or damage from the earthquake and the subsequent tsunami. The aim of this study was to evaluate the actual condition of patients with peptic ulcers related to the disaster. Methods Patients with peptic ulcers at six hospitals in three different regions of Fukushima Prefecture during the two months following the disaster and the corresponding period of the year before and the year after the disaster were enrolled in this study. Changes by period and region in the number of esophagogastroduodenoscopy (EGD) examinations and the number of peptic ulcer patients were evaluated as the primary endpoints. Changes in the frequencies of hemorrhagic ulcers were evaluated by period and by region as secondary endpoints. Results The numbers of EGDs and peptic ulcer cases compared to the previous year decreased in 2011 and then increased in 2012. However, the ratio of hemorrhagic ulcers to peptic ulcers was higher in 2011 (51.9%) than in 2010 (38.1%) and 2012 (31.1%), and the 2011 hemorrhagic ulcer ratio was the highest at 63.6% in the coastal area. Regarding bleeding cases during 2011, the rate at 1 month after the disaster (64.1%) was higher than the rate at 2 months after the disaster (40.5%) (p=0.033). Conclusion The number of patients with peptic ulcers did not increase immediately following the disaster in Fukushima Prefecture. However, the rate of bleeding patients increased soon after the disaster, especially in the coastal area. PMID:29269647

  17. Impact of the Great East Japan Earthquake on Regional Obstetrical Care in Miyagi Prefecture.

    PubMed

    Sugawara, Junichi; Hoshiai, Tetsuro; Sato, Kazuyo; Tokunaga, Hideki; Nishigori, Hidekazu; Arai, Takanari; Okamura, Kunihiro; Yaegashi, Nobuo

    2016-06-01

    The authors report the results of surveys on the emergency transport or evacuation status of obstetric patients conducted in Miyagi prefecture, one of the major disaster areas of the Great East Japan Earthquake and tsunami. The surveys examined the damages to maternity institutions, evacuation status and transport of pregnant women, and prehospital childbirths and were conducted in 50 maternity institutions and 12 fire departments in Miyagi. Two coastal institutions were destroyed completely, and four institutions were destroyed partially by the tsunami, forcing them to stop medical services. In the two-month period after the disaster, 217 pregnant women received hospital transport or gave birth after evacuation. Satisfactory perinatal outcomes were maintained. Emergency obstetric transport increased to approximately 1.4 fold the number before the disaster. Twenty-three women had prehospital childbirths, indicating a marked increase to approximately three times the number of the previous year. In the acute phase of the tsunami disaster, maternity institutions were damaged severely and perinatal transport was not possible; as a result, pregnant women inevitably gave birth in unplanned institutions, and the number of prehospital births was increased extremely. To obtain satisfactory obstetric outcomes, it is necessary to construct a future disaster management system and to re-recognize pregnant women as people with special needs in disaster situations. Sugawara J , Hoshiai T , Sato K , Tokunaga H , Nishigori H , Arai T , Okamura K , Yaegashi N . Impact of the Great East Japan Earthquake on regional obstetrical care in Miyagi Prefecture. Prehosp Disaster Med. 2016;31(3):255- 258.

  18. Impact of the Great East Japan Earthquake and tsunami on health, medical care and public health systems in Iwate Prefecture, Japan, 2011.

    PubMed

    Nohara, Masaru

    2011-10-01

    The Great East Japan Earthquake was one of the largest earthquakes ever recorded in global history. The damage was spread over a wide area, with the worst-hit areas being Iwate, Miyagi and Fukushima prefectures. In this paper we report on the damage and the impact of the damage to describe the health consequences among disaster victims in Iwate Prefecture. In Iwate Prefecture the tsunami claimed 4659 lives, with 1633 people missing. In addition to electricity, water and gas being cut off following the disaster, communication functions were paralysed and there was a lack of gasoline. Medical and public health teams from Iwate Prefecture and around the country, including many different specialists, engaged in a variety of public health activities mainly at evacuation centres, including medical and mental health care and activities to prevent infectious diseases. Given the many fatalities, there were relatively few patients who required medical treatment for major injuries. However, there were significant medical needs in the subacute and chronic phases of care in evacuation centres, with great demand for medical treatment and public health assistance, measures to counteract infection and mental health care. By referring to past experiences of national and international large-scale disasters, it was possible to respond effectively to the health-related challenges. However, there are still challenges concerning how to share information and coordinate overall activities among multiple public health response teams. Further examination will be required to ensure better preparedness in response to future disasters.

  19. SURFACE RUPTURE OF THE NORMAL SEISMIC FAULTS AND SLOPE FAILURES APPEARED IN APRIL 11th, 2011 FUKUSHIMA-PREFECTURE HAMADOORI EARTHQUAKE

    NASA Astrophysics Data System (ADS)

    Kazmi, Zaheer Abbas; Konagai, Kazuo; Kyokawa, Hiroyuki; Tetik, Cigdem

    On April 11th, 2011, Iwaki region of Fukushima prefecture was jolted by Fukushima-Prefecture Hamadoori Earthquake. Surface ruptures were observed along causative Idosawa and Yunotake normal faults. In addition to numerous small slope failures, a coherent landslide and building structures of Tabito Junior High School, bisected by Idosawa Fault, were found along the causative faults. A precise digital elevation model of the coherent landslide was obtained through the ground and air-born LiDAR surveys. The measurements of perimeters of the gymnasium building and the swimming pool of Tabito Junior High School have shown that ground undergoes a slow and steady/continual deformation.

  20. [The number of deaths by suicide after the Great East Japan Earthquake based on demographic statistics in the coastal and non-coastal areas of Iwate, Miyagi, and Fukushima prefectures].

    PubMed

    Masaki, Naoko; Hashimoto, Shuji; Kawado, Miyuki; Ojima, Toshiyuki; Takeshima, Tadashi; Matsubara, Miyuki; Mitoku, Kazuko; Ogata, Yukiko

    2018-01-01

    Objective The number of deaths by suicide after the Great East Japan Earthquake was surveyed based on demographic statistics. In particular, this study examined whether or not there were excessive deaths due to suicide (excluding people who were injured in the earthquake) after the Great East Japan Earthquake disaster. This examination surveyed municipalities in coastal and non-coastal areas of Iwate, Miyagi, and Fukushima prefectures (referred to below as the "three prefectures").Methods The demographic statistics questionnaire survey information supplied by Article 33 of the Statistics Act (Ministry of Health, Labour and Welfare's published statistics Vol. 0925 No.4, September 25 th , 2014) were used as the basic data with particular reference to the information on the deaths from January 1 st , 2010 to March 31 st , 2013. The information obtained included the date of death, the municipality where the address of the deceased was registered, the gender of the deceased, age at the time of death, and cause of death codes (International Classification of Disease Codes 10 th revision: ICD-10). Additionally, information was gathered about the population based on the resident register from 2009 to 2013 and the 2010 National Census; the number of deaths by suicide was then totalled by period and area. The areas were classified as municipalities within three prefectures and those located elsewhere using the municipality where the address of the deceased was registered.Results The SMR for suicides did not show a tendency to increase for coastal or non-coastal areas throughout the two-year period after the earthquake disaster (from March 2011 to February 2013). The SMR for the three prefectures 0-1 years after the disaster compared with the year before the disaster was 0.92 and for 1-2 years after the disaster was 0.93. Both these values were significantly low. Looking at both the non-coastal and coastal areas from each of the three prefectures, the SMR for suicides

  1. Relationships between mental health distress and work-related factors among prefectural public servants two months after the Great East Japan Earthquake.

    PubMed

    Fukasawa, Maiko; Suzuki, Yuriko; Obara, Akiko; Kim, Yoshiharu

    2015-02-01

    In times of disaster, public servants face multiple burdens as they engage in a demanding and stressful disaster-response work while managing their own needs caused by the disaster. We investigated the effects of work-related factors on the mental health of prefectural public servants working in the area devastated by the Great East Japan Earthquake to identify some ideas for organizational work modifications to protect their mental health. Two months after the earthquake, Miyagi prefecture conducted a self-administered health survey of prefectural public servants and obtained 4,331 (82.8%) valid responses. We investigated relationships between mental health distress (defined as K6 ≥ 13) and work-related variables (i.e., job type, overwork, and working environment) stratified by level of earthquake damage experienced. The proportion of participants with mental health distress was 3.0% in the group that experienced less damage and 5.9% in the group that experienced severe damage. In the group that experienced less damage, working >100 h of overtime per month (adjusted odds ratio [OR], 2.06; 95% confidence interval [CI], 1.11-3.82) and poor workplace communication (adjusted OR, 10.96; 95% CI, 6.63-18.09) increased the risk of mental health distress. In the group that experienced severe damage, handling residents' complaints (adjusted OR, 4.79; 95% CI, 1.55-14.82) and poor workplace communication (adjusted OR, 9.14; 95% CI, 3.34-24.97) increased the risk, whereas involvement in disaster-related work (adjusted OR, 0.39; 95% CI, 0.18-0.86) decreased the risk. Workers who have experienced less disaster-related damage might benefit from working fewer overtime hours, and those who have experienced severe damage might benefit from avoiding contact with residents and engaging in disaster-related work. Facilitating workplace communication appeared important for both groups of workers.

  2. The great East Japan earthquake disaster: distribution of hospital damage in Miyagi Prefecture.

    PubMed

    Ochi, Sae; Nakagawa, Atsuhiro; Lewis, James; Hodgson, Susan; Murray, Virginia

    2014-06-01

    In catastrophic events, a key to reducing health risks is to maintain functioning of local health facilities. However, little research has been conducted on what types and levels of care are the most likely to be affected by catastrophic events. Problem The Great East Japan Earthquake Disaster (GEJED) was one of a few "mega disasters" that have occurred in an industrialized society. This research aimed to develop an analytical framework for the holistic understanding of hospital damage due to the disaster. Hospital damage data in Miyagi Prefecture at the time of the GEJED were collected retrospectively. Due to the low response rate of questionnaire-based surveillance (7.7%), publications of the national and local governments, medical associations, other nonprofit organizations, and home web pages of hospitals were used, as well as literature and news sources. The data included information on building damage, electricity and water supply, and functional status after the earthquake. Geographical data for hospitals, coastline, local boundaries, and the in undated areas, as well as population size and seismic intensity were collected from public databases. Logistic regression was conducted to identify the risk factors for hospitals ceasing inpatient and outpatient services. The impact was displayed on maps to show the geographical distribution of damage. Data for 143 out of 147 hospitals in Miyagi Prefecture (97%) were obtained. Building damage was significantly associated with closure of both inpatient and outpatient wards. Hospitals offering tertiary care were more resistant to damage than those offering primary care, while those with a higher proportion of psychiatric care beds were more likely to cease functioning, even after controlling for hospital size, seismic intensity, and distance from the coastline. Implementation of building regulations is vital for all health care facilities, irrespective of function. Additionally, securing electricity and water supplies

  3. Similar microearthquakes observed in western Nagano, Japan, and implications for rupture mechanics

    NASA Astrophysics Data System (ADS)

    Cheng, Xin; Niu, Fenglin; Silver, Paul G.; Horiuchi, Shigeki; Takai, Kaori; Iio, Yoshihisa; Ito, Hisao

    2007-04-01

    We have applied a waveform cross correlation technique to study the similarity and the repeatability of more than 21,000 microearthquakes (0 < M < 4.5) in the aftershock zone of the 1984 western Nagano earthquake in central Japan. We find that the seismicity in this particular intraplate fault essentially consists of no repeating earthquakes that occurred on the same patch of the fault in a quasiperiodic manner in the study period between 1995 and 2001. On the other hand, we identify a total of 278 doublets and 62 multiplets (807 events) that occurred consecutively within seconds to days. On the basis of the relative arrival times of the P and S waves, we have obtained precise relative locations of these consecutive events with an error between several meters to a few tens of meters. There is a clear lower bound on the distances measured between these consecutive events and the lower bound appears to be proportional to the size of the first events. This feature is consistent with what Rubin and Gillard [2000] have observed near the San Juan Bautista section of the San Andreas Fault. Shear stress increases at the edge of an earthquake rupture, and the rupture edge becomes the most likely place where the second events are initiated. The observed minimum distance thus reflects the rupture size of the first events. The minimum distance corresponds to the rupture size calculated from a circular fault model with a stress drop of 10 MPa. We found that using different time windows results in a slight difference in the delay time estimates and the subsequent projection locations, which may reflect the finite size nature of earthquake ruptures.

  4. Pregnancy and birth survey after the Great East Japan Earthquake and Fukushima Daiichi Nuclear Power Plant accident in Fukushima prefecture.

    PubMed

    Fujimori, Keiya; Kyozuka, Hyo; Yasuda, Shun; Goto, Aya; Yasumura, Seiji; Ota, Misao; Ohtsuru, Akira; Nomura, Yasuhisa; Hata, Kenichi; Suzuki, Kouta; Nakai, Akihito; Sato, Mieko; Matsui, Shiro; Nakano, Kyoko; Abe, Masafumi

    2014-01-01

    On 11 March 2011, the Great East Japan Earthquake followed by a powerful tsunami hit the Pacific Coast of Northeast Japan and damaged Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant, causing a radiation hazard in Fukushima Prefecture. The objective of this report is to describe some results of a questionnaire-based pregnancy and birth survey conducted by the Radiation Medical Science Center for the Fukushima Health Management Survey. Questionnaires were sent to women who received maternal and child health handbooks from municipal officers in Fukushima Prefecture between 1 August 2010 and 31 July 2011, with the aim of reaching those who were pregnant at the time of the disaster. Mailing began 18 January 2012. Data were analyzed separately for six geographic areas in Fukushima Prefecture. The total number of women meeting survey criteria was 15,972. The number of responses received to date is 9,298 (58.2%). Data from 8602 respondents were analyzed after excluding 634 invalid responses and 5 induced and 57 spontaneous abortions (less than 22 gestational weeks). The incidences of stillbirth (over 22 completed gestational weeks), preterm birth, low birth weight and congenital anomalies were 0.25%, 4.4%, 8.7% and 2.72%, respectively. These incidences are similar to recent averages elsewhere in Japan. Considering the pregnancy and birth survey data in aggregate, our disaster seemed to provoke no significant adverse outcomes over the whole of Fukushima prefecture. But post-disaster prenatal care and support intended for patients' safety and security should be coupled with ongoing surveillance and rigorous data analysis.

  5. Re-examination of the original questionnaire documents for the 1944 Tonankai, 1945 Mikawa, and 1946 Nanaki earthquakes

    NASA Astrophysics Data System (ADS)

    Harada, Tomoya; Satake, Kenji; Furumura, Takashi

    2016-04-01

    With the object of estimating seismic intensity, the Earthquakes Research Institute (ERI) of the University of Tokyo performed questionnaire surveys for the significant (destructive or large/great) earthquakes from 1943 to 1988 (Kayano, 1990, BERI). In these surveys, Kawasumi (1943)'s 12-class seismic intensity scale similar to the Modified Mercalli scale (MM-scale) was used. Survey results for earthquakes after 1950 were well investigated and published (e.g. Kayano and Komaki, 1977, BERI; Kayano and Sato, 1975, BERI), but the survey results for earthquakes in the 1940s have not been published and original documents of the surveys was missing. Recently, the original sheets of the surveys for the five earthquakes in the 1940s with more than 1,000 casualties were discovered in the ERI warehouse, although they are incomplete (Tsumura et al, 2010). They are from the 1943 Tottori (M 7.2), 1944 Tonankai (M 7.9), 1945 Mikawa (M 6.8), 1946 Nankai (M 8.0), and 1948 Fukui (M 7.1) earthquakes. In this study, we examined original questionnaire and summary sheets for the 1944 Tonankai, 1945 Mikawa, and 1946 Nanaki earthquakes, and estimated the distributions of seismic intensity, various kinds of damage, and human behaviors in detail. Numbers of the survey points for the 1944, 1945, and 1946 event are 287, 145, and 1,014, respectively. The numbers for the 1944 and 1945 earthquakes are much fewer than that of the 1946 event, because they occurred during the last years of World War II. The 1944 seismic intensities in the prefectures near the source region (Aichi, Mie, Shizuoka, and Gifu Pref.) tend to be high. However, the 1944 intensities are also high and damage is serious at the Suwa Lake shore in Nagano Pref. which is about 240 km far from the source region because seismic waves are amplified dramatically in the thick sediment in the Suwa Basin. Seismic intensities of the 1945 Mikawa earthquake near the source region in Aichi Pref. were very high (X-XI). However, the

  6. Coseismic fault zone deformation caused by the 2014 Mw=6.2 Nagano-ken-hokubu, Japan, earthquake on the Itoigawa-Shizuoka Tectonic Line revealed with differential LiDAR

    NASA Astrophysics Data System (ADS)

    Toda, S.; Ishimura, D.; Homma, S.; Mukoyama, S.; Niwa, Y.

    2015-12-01

    The Mw = 6.2 Nagano-ken-hokubu earthquake struck northern Nagano, central Japan, on November 22, 2014, and accompanied a 9-km-long surface rupture mostly along the previously mapped N-NW trending Kamishiro fault, one of the segments of the 150-km-long Itoigawa-Shizuoka Tectonic Line active fault system. While we mapped the rupture and measured vertical displacement of up to 80 cm at the field, interferometric synthetic aperture radar (InSAR) shows densely spaced fringes on the hanging wall side, suggesting westward or uplift movement associated with thrust faulting. The mainshock focal mechanism and aftershock hypocenters indicate the source fault dips to the east but the InSAR images cannot exactly differentiate between horizontal and vertical movements and also lose coherence within and near the fault zone itself. To reveal near-field deformation and shallow fault slip, here we demonstrate a differential LiDAR analysis using a pair of 1 m-resolution pre-event and post-event bare Earth digital terrain models (DTMs) obtained from commercial LiDAR provider. We applied particle image velocity (PIV) method incorporating elevation change to obtain 3-D vectors of coseismic displacements (Mukoyama, 2011, J. Mt. Sci). Despite sporadic noises mostly due to local landslides, we detected up to 1.5 m net movement at the tip of the hanging wall, more than the field measurement of 80 cm. Our result implies that a 9-km-long rupture zone is not a single continuous fault but composed of two bow-shaped fault strands, suggesting a combination of shallow fault dip and modest amount (< 1.5 m) of slip. Eastward movement without notable subsidence on the footwall also supports the low angle fault dip near the surface, and significant fault normal contraction, observed as buckled cultural features across the fault zone. Secondary features, such as subsidiary back-thrust faults confirmed at the field, are also visible as a significant contrast of vector directions and slip amounts.

  7. Mental Health Distress and Related Factors Among Prefectural Public Servants Seven Months After the Great East Japan Earthquake

    PubMed Central

    Suzuki, Yuriko; Fukasawa, Maiko; Obara, Akiko; Kim, Yoshiharu

    2014-01-01

    Background To develop an empirically informed support measure for workers, we examined mental health distress and its risk factors among prefectural public servants who were affected by the Great East Japan Earthquake and faced a demanding workload in the midterm of the disaster. Methods We conducted a self-administered health survey of all public servants in the Miyagi prefectural government two and seven months after the Great East Japan Earthquake (3743 workers, 70.6% of all employees). We calculated odds ratios (ORs) and 95% confidence intervals (CIs) for mental distress (defined as K6 score ≥10) in the domain of disaster-work-related stressors, work-related stressors, and disaster-related stressors. Results Among those with better levels of workplace communication, the only factor that increased the risk of mental distress was not taking a non-work day each week (adjusted OR 2.55, 95% CI 1.27–5.14). Among those with poorer levels of workplace communication, in addition to not taking a non-work day each week (adjusted OR 3.93, 95% CI 3.00–5.15), handling residents’ complaints (adjusted OR 1.55, 95% CI 1.00–2.42), having dead or missing family members (adjusted OR 2.87, 95% CI 1.53–5.38), and living in a shelter more than two months after the disaster (adjusted OR 2.80, 95% CI 1.32–5.95) increased the risk of mental distress. Conclusions All workers should be encouraged to take a non-work day each week. Among workers with poor workplace communication, special attention should be given to those who handle residents’ complaints, have lost a family member(s), and are living in a shelter for a prolonged period of time. PMID:24857952

  8. Inhibition of low-density lipoprotein oxidation by Nagano purple grape (Vitis viniferaxVitis labrusca).

    PubMed

    Kamiyama, Masumi; Kishimoto, Yoshimi; Tani, Mariko; Andoh, Kunihiko; Utsunomiya, Kazunori; Kondo, Kazuo

    2009-12-01

    The Nagano Purple grape (Vitis (V.) viniferaxV. labrusca) is a hybrid created by a cross between Kyoho (V. viniferaxV. labrusca) and Rosario Bianco (V. vinifera) grapes. The grape, including its skin, can be eaten and contains no seeds because of gibberellin treatment. The skins of various fruits have been shown to contain antioxidant activity. However, it is unclear whether the Nagano Purple grape contains antioxidant activity. We prepared the skins and dried fruits (including the skins) of the Nagano Purple grape, so as to assay for the presence of an antioxidant activity. We examined the concentration of polyphenols in the grape and further assayed whether components in the grape inhibited the oxidation of low-density lipoprotein (LDL). We detected the presence of cyanidin-3-glucoside (Cy-3-glc), five anthocyanidins and resveratrol in the skins. A trace of resveratrol was detected in the pulp. LDL collected from human subjects 1 h following the consumption of the skins or dried fruits revealed significant inhibition of LDL oxidation compared to that observed in fasting venous blood samples. We further observed the antioxidant activity of Cy-3-glc. Our results suggest that the consumption of the Nagano Purple grape can give rise to resistance to LDL oxidation.

  9. Influence of the Great East Japan Earthquake and the Fukushima Daiichi nuclear disaster on the birth weight of newborns in Fukushima Prefecture: Fukushima Health Management Survey.

    PubMed

    Yasuda, Shun; Kyozuka, Hyo; Nomura, Yasuhisa; Fujimori, Keiya; Goto, Aya; Yasumura, Seiji; Hata, Kennichi; Ohira, Tetsuya; Abe, Masafumi

    2017-12-01

    The Great East Japan Earthquake and Fukushima Daiichi nuclear disaster occurred on 11 March 2011. We investigated the incidence of SGA (small for gestational age) in the Fukushima Prefecture in newborns delivered by women who were pregnant at the time of the disasters and identified any risk factors for SGA. Subjects were women who were pregnant at the time of the disasters. Questionnaires were sent to the women who lived in the Hamadori area (seaside and near to the nuclear power plant) at the time of the disasters as well as to a control group of women who lived outside the Hamadori area. The incidence of SGA was compared. Logistic regression analysis was performed to identify the risk factors for SGA. In total, 325(5.6%) women had infants with SGA. Neither area nor the trimester of pregnancy at the time of the disasters influenced the incidence of SGA. Pregnancy-induced hypertension (PIH) was higher in the SGA group. PIH was found to be an independent risk factor for SGA. We found no evidence that the Great East Japan Earthquake and the Fukushima Daiichi nuclear disaster increased the incidence of SGA in the Fukushima Prefecture.

  10. Impact of the great east Japan earthquake on the body mass index of preschool children: a nationwide nursery school survey.

    PubMed

    Yokomichi, Hiroshi; Zheng, Wei; Matsubara, Hiroko; Ishikuro, Mami; Kikuya, Masahiro; Isojima, Tsuyoshi; Yokoya, Susumu; Tanaka, Toshiaki; Kato, Noriko; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Tanaka, Soichiro; Kuriyama, Shinichi; Kure, Shigeo; Yamagata, Zentaro

    2016-04-07

    To evaluate the impact of the 2011 great east Japan earthquake on body mass index (BMI) of preschool children. Retrospective cohort study and ecological study. Affected prefectures (Fukushima, Miyagi and Iwate) and unaffected prefectures in northeast Japan. The cohort study assessed 2033 and 1707 boys and 1909 and 1658 girls in 3 affected prefectures and unaffected prefectures, respectively, all aged 3-4 years at the time of the earthquake. The ecological study examined random samples of schoolchildren from the affected prefectures. The cohort study compared postdisaster changes in BMIs and the prevalence of overweight and obese children. The ecological study evaluated postdisaster changes in the prevalence of overweight children. 1 month after the earthquake, significantly increased BMIs were observed among girls (+0.087 kg/m(2) vs unaffected prefectures) in Fukushima and among boys and girls (+0.165 and +0.124 kg/m(2), respectively vs unaffected prefectures) in Iwate. 19 months after the earthquake, significantly increased BMIs were detected among boys and girls (+0.137 and +0.200 kg/m(2), respectively vs unaffected prefectures) in Fukushima, whereas significantly decreased BMIs were observed among boys and girls (-0.218 and -0.082 kg/m(2), respectively vs unaffected prefectures) in Miyagi. 1 month after the earthquake, Fukushima, Miyagi and Iwate had a slightly increased prevalence of overweight boys, whereas Fukushima had a slightly decreased prevalence of overweight girls, compared with the unaffected prefectures. The ecological study detected increases in the prevalence of overweight boys and girls in Fukushima who were 6-11 and 6-10 years of age, respectively. These results suggest that in the affected prefectures, preschool children gained weight immediately after the earthquake. The long-term impact of the earthquake on early childhood growth was more variable among the affected prefectures, possibly as a result of different speeds of

  11. Survey of Preventable Disaster Deaths at Medical Institutions in Areas Affected by the Great East Japan Earthquake: Retrospective Survey of Medical Institutions in Miyagi Prefecture.

    PubMed

    Yamanouchi, Satoshi; Sasaki, Hiroyuki; Kondo, Hisayoshi; Mase, Tomohiko; Otomo, Yasuhiro; Koido, Yuichi; Kushimoto, Shigeki

    2017-10-01

    Introduction In 2015, the authors reported the results of a preliminary investigation of preventable disaster deaths (PDDs) at medical institutions in areas affected by the Great East Japan Earthquake (2011). This initial survey considered only disaster base hospitals (DBHs) and hospitals that had experienced at least 20 patient deaths in Miyagi Prefecture (Japan); therefore, hospitals that experienced fewer than 20 patient deaths were not investigated. This was an additional study to the previous survey to better reflect PDD at hospitals across the entire prefecture. Of the 147 hospitals in Miyagi Prefecture, the 14 DBHs and 82 non-DBHs that agreed to participate were included in an on-site survey. A database was created based on the medical records of 1,243 patient deaths that occurred between March 11, 2011 and April 1, 2011, followed by determination of their status as PDDs. A total of 125 cases of PDD were identified among the patients surveyed. The rate of PDD was significantly higher at coastal hospitals than inland hospitals (17.3% versus 6.3%; P<.001). Preventable disaster deaths in non-DBHs were most numerous in facilities with few general beds, especially among patients hospitalized before the disaster in hospitals with fewer than 100 beds. Categorized by area, the most frequent causes of PDD were: insufficient medical resources, disrupted lifelines, delayed medical intervention, and deteriorated environmental conditions in homes and emergency shelters in coastal areas; and were delayed medical intervention and disrupted lifelines in inland areas. Categorized by hospital function, the most frequent causes were: delayed medical intervention, deteriorated environmental conditions in homes and emergency shelters, and insufficient medical resources at DBHs; while those at non-DBHs were disrupted lifelines, insufficient medical resources, delayed medical intervention, and lack of capacity for transport within the area. Preventable disaster death at medical

  12. Paleoseismic study of the Kamishiro Fault on the northern segment of the Itoigawa-Shizuoka Tectonic Line, Japan

    NASA Astrophysics Data System (ADS)

    Lin, Aiming; Sano, Mikako; Wang, Maomao; Yan, Bing; Bian, Di; Fueta, Ryoji; Hosoya, Takashi

    2017-07-01

    The Mw 6.2 (Mj 6.8) Nagano (Japan) earthquake of 22 November 2014 produced a 9.3-km long surface rupture zone with a thrust-dominated displacement of up to 1.5 m, which duplicated the pre-existing Kamishiro Fault along the Itoigawa-Shizuoka Tectonic Line (ISTL), the plate-boundary between the Eurasian and North American plates, northern Nagano Prefecture, central Japan. To characterize the activity of the seismogenic fault zone, we conducted a paleoseismic study of the Kamishiro Fault. Field investigations and trench excavations revealed that seven morphogenic paleohistorical earthquakes (E2-E8) prior to the 2014 Mw 6.2 Nagano earthquake (E1) have occurred on the Kamishiro Fault during the last ca. 6000 years. Three of these events (E2-E4) are well constrained and correspond to historical earthquakes occurring in the last ca. 1200 years. This suggests an average recurrence interval of ca. 300-400 years on the seismogenic fault of the 2014 Kamishiro earthquake in the past 1200 years. The most recent event prior to the 2014 earthquakes (E1) is E2 and the penultimate and antepenultimate faulting events are E3 and E4, respectively. The penultimate faulting event (E3) occurred during the period of AD 1800-1400 and is associated with the 1791 Mw 6.8 earthquake. The antepenultimate faulting event (E4) is inferred to have occurred during the period of ca. AD 1000-700, likely corresponding to the AD 841 Mw 6.5 earthquake. The oldest faulting event (E8) in the study area is thought to have occurred during the period of ca. 5600-6000 years. The throw rate during the early Holocene is estimated to be 1.2-3.3 mm/a (average, 2.2 mm/a) with an average amount of characteristic offset of 0.7-1.1 m produced by individual event. When compared with active intraplate faults on Honshu Island, Japan, these slip rates and recurrence interval estimated for morphogenic earthquakes on the Kamishiro Fault along the ISTL appear high and short, respectively. This indicates that present activity

  13. Paleoseismic study of the Kamishiro Fault on the northern segment of the Itoigawa-Shizuoka Tectonic Line, Japan.

    PubMed

    Lin, Aiming; Sano, Mikako; Wang, Maomao; Yan, Bing; Bian, Di; Fueta, Ryoji; Hosoya, Takashi

    2017-01-01

    The M w 6.2 (Mj 6.8) Nagano (Japan) earthquake of 22 November 2014 produced a 9.3-km long surface rupture zone with a thrust-dominated displacement of up to 1.5 m, which duplicated the pre-existing Kamishiro Fault along the Itoigawa-Shizuoka Tectonic Line (ISTL), the plate-boundary between the Eurasian and North American plates, northern Nagano Prefecture, central Japan. To characterize the activity of the seismogenic fault zone, we conducted a paleoseismic study of the Kamishiro Fault. Field investigations and trench excavations revealed that seven morphogenic paleohistorical earthquakes (E2-E8) prior to the 2014 M w 6.2 Nagano earthquake (E1) have occurred on the Kamishiro Fault during the last ca. 6000 years. Three of these events (E2-E4) are well constrained and correspond to historical earthquakes occurring in the last ca. 1200 years. This suggests an average recurrence interval of ca. 300-400 years on the seismogenic fault of the 2014 Kamishiro earthquake in the past 1200 years. The most recent event prior to the 2014 earthquakes (E1) is E2 and the penultimate and antepenultimate faulting events are E3 and E4, respectively. The penultimate faulting event (E3) occurred during the period of AD 1800-1400 and is associated with the 1791 M w 6.8 earthquake. The antepenultimate faulting event (E4) is inferred to have occurred during the period of ca. AD 1000-700, likely corresponding to the AD 841 M w 6.5 earthquake. The oldest faulting event (E8) in the study area is thought to have occurred during the period of ca. 5600-6000 years. The throw rate during the early Holocene is estimated to be 1.2-3.3 mm/a (average, 2.2 mm/a) with an average amount of characteristic offset of 0.7-1.1 m produced by individual event. When compared with active intraplate faults on Honshu Island, Japan, these slip rates and recurrence interval estimated for morphogenic earthquakes on the Kamishiro Fault along the ISTL appear high and short, respectively. This indicates that

  14. Structural Changes in Molluscan Community over a 15-Year Period before and after the 2011 Great East Japan Earthquake and Subsequent Tsunami around Matsushima Bay, Miyagi Prefecture, Northeastern Japan.

    PubMed

    Sato, Shin'ichi; Chiba, Tomoki

    2016-01-01

    We examined structural changes in the molluscan community for ten years (2001-2010) before and five years (2011-2015) after the 2011 Great East Japan Earthquake and subsequent tsunami around Matsushima Bay, Miyagi Prefecture, northeastern Japan. Before the earthquake and tsunami, Ruditapes philippinarum, Macoma incongrua, Pillucina pisidium, and Batillaria cumingii were dominant, and an alien predator Laguncula pulchella appeared in 2002 and increased in number. After the tsunami, R. philippinarum and M. incongrua populations quickly recovered in 2012, but P. pisidium and B. cumingii populations did not recover until 2015. By contrast, Musculista senhousia, Mya arenaria, Retusa sp., and Solen strictus were found in low densities before the tsunami, but they rapidly increased in abundance/number over five years after the tsunami. These results suggest that the molluscan community on the Tona Coast was drastically changed by the earthquake and tsunami, and some species mainly inhabiting the intertidal-subtidal zone may have increased in number because of land subsidence. We also emphasize that the seawall delayed recovery of the intertidal community after the earthquake and tsunami.

  15. Structural Changes in Molluscan Community over a 15-Year Period before and after the 2011 Great East Japan Earthquake and Subsequent Tsunami around Matsushima Bay, Miyagi Prefecture, Northeastern Japan

    PubMed Central

    Chiba, Tomoki

    2016-01-01

    We examined structural changes in the molluscan community for ten years (2001–2010) before and five years (2011–2015) after the 2011 Great East Japan Earthquake and subsequent tsunami around Matsushima Bay, Miyagi Prefecture, northeastern Japan. Before the earthquake and tsunami, Ruditapes philippinarum, Macoma incongrua, Pillucina pisidium, and Batillaria cumingii were dominant, and an alien predator Laguncula pulchella appeared in 2002 and increased in number. After the tsunami, R. philippinarum and M. incongrua populations quickly recovered in 2012, but P. pisidium and B. cumingii populations did not recover until 2015. By contrast, Musculista senhousia, Mya arenaria, Retusa sp., and Solen strictus were found in low densities before the tsunami, but they rapidly increased in abundance/number over five years after the tsunami. These results suggest that the molluscan community on the Tona Coast was drastically changed by the earthquake and tsunami, and some species mainly inhabiting the intertidal—subtidal zone may have increased in number because of land subsidence. We also emphasize that the seawall delayed recovery of the intertidal community after the earthquake and tsunami. PMID:27936182

  16. SAR-revealed slip partitioning on a bending fault plane for the 2014 Northern Nagano earthquake at the northern Itoigawa-Shizuoka tectonic line

    NASA Astrophysics Data System (ADS)

    Kobayashi, Tomokazu; Morishita, Yu; Yarai, Hiroshi

    2018-05-01

    By applying conventional cross-track synthetic aperture radar interferometry (InSAR) and multiple aperture InSAR techniques to ALOS-2 data acquired before and after the 2014 Northern Nagano, central Japan, earthquake, a three-dimensional ground displacement field has been successfully mapped. Crustal deformation is concentrated in and around the northern part of the Kamishiro Fault, which is the northernmost section of the Itoigawa-Shizuoka tectonic line. The full picture of the displacement field shows contraction in the northwest-southeast direction, but northeastward movement along the fault strike direction is prevalent in the northeast portion of the fault, which suggests that a strike-slip component is a significant part of the activity of this fault, in addition to a reverse faulting. Clear displacement discontinuities are recognized in the southern part of the source region, which falls just on the previously known Kamishiro Fault trace. We inverted the SAR and GNSS data to construct a slip distribution model; the preferred model of distributed slip on a two-plane fault surface shows a combination of reverse and left-lateral fault motions on a bending east-dipping fault surface with a dip of 30° in the shallow part and 50° in the deeper part. The hypocenter falls just on the estimated deeper fault plane where a left-lateral slip is inferred, whereas in the shallow part, a reverse slip is predominant, which causes surface ruptures on the ground. The slip partitioning may be accounted for by shear stress resulting from a reverse fault slip with left-lateral component at depth, for which a left-lateral slip is suppressed in the shallow part where the reverse slip is inferred. The slip distribution model with a bending fault surface, instead of a single fault plane, produces moment tensor solution with a non-double couple component, which is consistent with the seismically estimated mechanism.

  17. An overview of the geotechnical damage brought by the 2016 Kumamoto Earthquake, Japan

    USGS Publications Warehouse

    Hemanta Hazarika,; Takaji Kokusho,; Kayen, Robert E.; Dashti, Shideh; Yutaka Tanoue,; Shuuichi Kuroda and Kentaro Kuribayashi,; Daisuke Matsumoto,; Furuichi, Hideo

    2016-01-01

    The 2016 Kumamoto earthquake with a moment magnitude of 7.0 (Japanese intensity = 7) that struck on April 16 brought devastation in many areas of Kumamoto Prefecture and partly in Oita Prefecture in Kyushu Region, Japan. The earthquake succeeds a foreshock of magnitude 6.5 (Japanese intensity = 7) on April 14. The authors conducted two surveys on the devastated areas: one during April 16-17, and the other during May 11-14. This report summarizes the damage brought to geotechnical structures by the two consecutive earthquakes within a span of twenty-eight hours. This report highlights some of the observed damage and identifies reasons for such damage. The geotechnical challenges towards mitigation of losses from such earthquakes are also suggested.

  18. Water supply facility damage and water resource operation at disaster base hospitals in miyagi prefecture in the wake of the Great East Japan Earthquake.

    PubMed

    Matsumura, Takashi; Osaki, Shizuka; Kudo, Daisuke; Furukawa, Hajime; Nakagawa, Atsuhiro; Abe, Yoshiko; Yamanouchi, Satoshi; Egawa, Shinichi; Tominaga, Teiji; Kushimoto, Shigeki

    2015-04-01

    The aim of this study was to shed light on damage to water supply facilities and the state of water resource operation at disaster base hospitals in Miyagi Prefecture (Japan) in the wake of the Great East Japan Earthquake (2011), in order to identify issues concerning the operational continuity of hospitals in the event of a disaster. In addition to interview and written questionnaire surveys to 14 disaster base hospitals in Miyagi Prefecture, a number of key elements relating to the damage done to water supply facilities and the operation of water resources were identified from the chronological record of events following the Great East Japan Earthquake. Nine of the 14 hospitals experienced cuts to their water supplies, with a median value of three days (range=one to 20 days) for service recovery time. The hospitals that could utilize well water during the time that water supply was interrupted were able to obtain water in quantities similar to their normal volumes. Hospitals that could not use well water during the period of interruption, and hospitals whose water supply facilities were damaged, experienced significant disruption to dialysis, sterilization equipment, meal services, sanitation, and outpatient care services, though the extent of disruption varied considerably among hospitals. None of the hospitals had determined the amount of water used for different purposes during normal service or formulated a plan for allocation of limited water in the event of a disaster. The present survey showed that it is possible to minimize the disruption and reduction of hospital functions in the event of a disaster by proper maintenance of water supply facilities and by ensuring alternative water resources, such as well water. It is also clear that it is desirable to conclude water supply agreements and formulate strategic water allocation plans in preparation for the eventuality of a long-term interruption to water services.

  19. Lessons learned from the 2016 Kumamoto earthquake: Building damages and behavior of seismically isolated buildings

    NASA Astrophysics Data System (ADS)

    Morita, Keiko; Takayama, Mineo

    2017-10-01

    Powerful earthquakes stuck Kumamoto and Oita Prefectures in Kyushu, Japan. It began with the Magnitude 6.5 foreshock at 21:26 JST 14 April, followed by the Magnitude 7.3 mainshock at 1:25 JST 16 April, 2016. The sequence earthquakes also involved more than 1700 perceptible earthquakes as of 13 June. The entire sequence was named the 2016 Kumamoto earthquake by the Japan Meteorological Agency. Thousands of buildings and many roads were damaged, and landslides occurred. The Japanese building standard law is revised in 1981. Structural damages were concentrated on buildings constructed prior to 1981. The area of Mashiki and Southern Aso were most badly affected, especially wooden houses extremely damaged. In Japan, Prof. Hideyuki Tada (title at the time) undertook research on laminated rubber bearings in 1978, and put it into practical use in 1981. The single family house at Yachiyodai, Chiba Prefecture is completed in 1983, it's the first seismically isolated building which is installed laminated rubber bearings in Japan. Afterward, this system is gradually adopted to mainly office buildings, like a research laboratory, a hospital, a computer center and other offices. In the 1994 Northridge earthquake, the 1995 Kobe earthquake and 2011 Tohoku earthquake, seismically isolated buildings improve these good performances, and recently number of the buildings have increased, mainly high risk area of earthquakes. Many people believed that Kumamoto was a low risk area. But there were 24 seismically isolated buildings in Kumamoto Prefecture at the time. The seismically isolated buildings indicated excellent performances during the earthquakes. They protected people, buildings and other important facilities from damages caused by the earthquake. The purpose of this paper is to discuss lessons learned from the 2016 Kumamoto earthquake and behavior of seismically isolated buildings in the earthquake.

  20. Recent damaging earthquakes in Japan, 2003-2008

    USGS Publications Warehouse

    Kayen, Robert E

    2008-01-01

    During the last six years, from 2003-2008, Japan has been struck by three significant and damaging earthquakes: The most recent M6.6 Niigata Chuetsu Oki earthquake of July 16, 2007 off the coast of Kashiwazaki City, Japan; The M6.6 Niigata Chuetsu earthquake of October 23, 2004, located in Niigata Prefecture in the central Uonuma Hills; and the M8.0 Tokachi Oki Earthquake of September 26, 2003 effecting southeastern Hokkaido Prefecture. These earthquakes stand out among many in a very active period of seismicity in Japan. Within the upper 100 km of the crust during this period, Japan experienced 472 earthquakes of magnitude 6, or greater. Both Niigata events affected the south-central region of Tohoku Japan, and the Tokachi-Oki earthquake affected a broad region of the continental shelf and slope southeast of the Island of Hokkaido. This report is synthesized from the work of scores of Japanese and US researchers who led and participated in post-earthquake reconnaissance of these earthquakes: their noteworthy and valuable contributions are listed in an extended acknowledgements section at the end of the paper. During the Niigata Chuetsu Oki event of 2007, damage to the Kashiwazaki-Kariwa nuclear power plant, structures, infrastructure, and ground were primarily the product of two factors: (1) high intensity motions from this moderate-sized shallow event, and (2) soft, poor performing, or liquefiable soils in the coastal region of southwestern Niigata Prefecture. Structural and geotechnical damage along the slopes of dunes was ubiquitous in the Kashiwazaki-Kariwa region. The 2004 Niigata Chuetsu Earthquake was the most significant to affect Japan since the 1995 Kobe earthquake. Forty people were killed, almost 3,000 were injured, and many hundreds of landslides destroyed entire upland villages. Landslides were of all types; some dammed streams, temporarily creating lakes threatening to overtop their new embankments and cause flash floods and mudslides. The numerous

  1. Alterations in physique among young children after the Great East Japan Earthquake: Results from a nationwide survey.

    PubMed

    Kikuya, Masahiro; Matsubara, Hiroko; Ishikuro, Mami; Sato, Yuki; Obara, Taku; Metoki, Hirohito; Isojima, Tsuyoshi; Yokoya, Susumu; Kato, Noriko; Tanaka, Toshiaki; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Yokomichi, Hiroshi; Yamagata, Zentaro; Tanaka, Soichiro; Kure, Shigeo; Kuriyama, Shinichi

    2017-10-01

    Data for earthquake-related alterations in physique among young children in developed countries is lacking. The Great East Japan Earthquake caused severe damage in Iwate, Miyagi, and Fukushima Prefectures in northeastern Japan. We retrospectively obtained anthropometric measurements in nursery school from 40,046 (cohort 1, historical control) and 53,492 (cohort 2) children aged 3.5-4.5 years without overweight in October 2008, and in October 2010, respectively. At the time of the earthquake in March, 2011, children in cohort 1 had already graduated from nursery school; however, children in cohort 2 were still enrolled in nursery school at this time. We compared the onset of overweight at 1 year after the baseline between children enrolled in their school located in one of the three target prefectures versus those in other prefectures using a logistic regression model, with adjustment for sex, age, history of disease, and obesity index at baseline. Overweight was defined as an obesity index of >+15%, which was calculated as (weight minus sex- and height-specific standard weight)/sex- and height-specific standard weight. The odds ratio (OR) for the onset of overweight in the three target prefectures was significant in cohort 2 (OR 1.25; 95% confidence interval [CI], 1.01-1.55) but not in cohort 1. When the two cohort were pooled (n = 93,538), the OR of the interaction term for school location × cohort was significant (OR 1.56; 95% CI, 1.09-2.23). Incident overweight in young children was significantly more common in the three prefectures affected by the Great East Japan Earthquake than in other prefectures after the disaster. Copyright © 2017 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  2. Impact of the Great East Japan Earthquake and Fukushima Nuclear Power Plant Accident on Assisted Reproductive Technology in Fukushima Prefecture: The Fukushima Health Management Survey.

    PubMed

    Hayashi, Masako; Fujimori, Keiya; Yasumura, Seiji; Nakai, Akihito

    2017-09-01

    The aim of the study was to evaluate the incidences and obstetric outcomes of women who conceived using assisted reproductive technology (ART) procedures in Fukushima Prefecture before and after the Great East Japan Earthquake and Fukushima nuclear power plant accident. Information was collected and analyzed from 12,070 women who conceived with or without ART in Fukushima Prefecture during the 9 months before and after the disaster. During the 9 months before and after the disaster, 138 (2.0%) and 102 (1.9%) women conceived with in vitro fertilization-embryo transfer (IVF-ET), respectively. The proportion of women who conceived with IVF-ET decreased during the 2 months immediately after the disaster, but returned to pre-disaster levels 3 months after the disaster. In the case of women who conceived without IVF-ET, the incidences of preterm birth and low birth weight increased after the disaster. In contrast, women who conceived with IVF-ET did not differ significantly in obstetric outcomes before and after the disaster but had a higher incidence of cesarean section and low birth weight compared to those conceived without IVF-ET, regardless of the study period. The influence of the disaster on woman who conceived using ART procedures was minimal.

  3. Impact of the Great East Japan Earthquake and Fukushima Nuclear Power Plant Accident on Assisted Reproductive Technology in Fukushima Prefecture: The Fukushima Health Management Survey

    PubMed Central

    Hayashi, Masako; Fujimori, Keiya; Yasumura, Seiji; Nakai, Akihito

    2017-01-01

    Background The aim of the study was to evaluate the incidences and obstetric outcomes of women who conceived using assisted reproductive technology (ART) procedures in Fukushima Prefecture before and after the Great East Japan Earthquake and Fukushima nuclear power plant accident. Methods Information was collected and analyzed from 12,070 women who conceived with or without ART in Fukushima Prefecture during the 9 months before and after the disaster. Results During the 9 months before and after the disaster, 138 (2.0%) and 102 (1.9%) women conceived with in vitro fertilization-embryo transfer (IVF-ET), respectively. The proportion of women who conceived with IVF-ET decreased during the 2 months immediately after the disaster, but returned to pre-disaster levels 3 months after the disaster. In the case of women who conceived without IVF-ET, the incidences of preterm birth and low birth weight increased after the disaster. In contrast, women who conceived with IVF-ET did not differ significantly in obstetric outcomes before and after the disaster but had a higher incidence of cesarean section and low birth weight compared to those conceived without IVF-ET, regardless of the study period. Conclusion The influence of the disaster on woman who conceived using ART procedures was minimal. PMID:28811855

  4. Survey of preventable disaster death at medical institutions in areas affected by the Great East Japan Earthquake: a retrospective preliminary investigation of medical institutions in Miyagi Prefecture.

    PubMed

    Yamanouchi, Satoshi; Sasaki, Hiroyuki; Tsuruwa, Miho; Ueki, Yuzuru; Kohayagawa, Yoshitaka; Kondo, Hisayoshi; Otomo, Yasuhiro; Koido, Yuichi; Kushimoto, Shigeki

    2015-04-01

    The 2011, magnitude (M) 9, Great East Japan Earthquake and massive tsunami caused widespread devastation and left approximately 18,500 people dead or missing. The incidence of preventable disaster death (PDD) during the Great East Japan Earthquake remains to be clarified; the present study investigated PDD at medical institutions in areas affected by the Great East Japan Earthquake in order to improve disaster medical systems. A total of 25 hospitals in Miyagi Prefecture (Japan) that were disaster base hospitals (DBHs), or had at least 20 patient deaths between March 11, 2011 and April 1, 2011, were selected to participate based on the results of a previous study. A database was created using the medical records of all patient deaths (n=868), and PDD was determined from discussion with 10 disaster health care professionals. A total of 102 cases of PDD were identified at the participating hospitals. The rate of PDD was higher at coastal hospitals compared to inland hospitals (62/327, 19.0% vs 40/541, 7.4%; P<.01). No difference was observed in overall PDD rates between DBHs and general hospitals (GHs); however, when analysis was limited to cases with an in-hospital cause of PDD, the PDD rate was higher at GHs compared to DBHs (24/316, 7.6% vs 21/552, 3.8%; P<.05). The most common causes of PDD were: insufficient medical resources, delayed medical intervention, disrupted lifelines, deteriorated environmental conditions in homes and emergency shelters at coastal hospitals, and delayed medical intervention at inland hospitals. Meanwhile, investigation of PDD causes based on type of medical institution demonstrated that, while delayed medical intervention and deteriorated environmental conditions in homes and emergency shelters were the most common causes at DBHs, insufficient medical resources and disrupted lifelines were prevalent causes at GHs. Preventable disaster death at medical institutions in areas affected by the Great East Japan Earthquake occurred mainly at

  5. Spatial distribution of F-net moment tensors for the 2005 West Off Fukuoka Prefecture Earthquake determined by the extended method of the NIED F-net routine

    NASA Astrophysics Data System (ADS)

    Matsumoto, Takumi; Ito, Yoshihiro; Matsubayashi, Hirotoshi; Sekiguchi, Shoji

    2006-01-01

    The 2005 West Off Fukuoka Prefecture Earthquake with a Japan Meteorological Agency (JMA) magnitude (MJMA) of 7.0 occurred on March 20, 2005. We determined moment tensor solutions, using a surface wave with an extended method of the NIED F-net routine processing. The horizontal distance to the station is rounded to the nearest interval of 1 km, and the variance reduction approach is applied to a focal depth from 2 km with an interval of 1 km. We obtain the moment tensors of 101 events with (MJMA) exceeding 3.0 and spatial distribution of these moment tensors. The focal mechanism of aftershocks is mainly of the strike-slip type. The alignment of the epicenters in the rupture zone of the main-shock is oriented between N110°E and N130°E, which is close to the strike of the main-shock's moment tensor solutions (N122°E). These moment tensor solutions of intermediatesized aftershocks around the focal region represent basic and important information concerning earthquakes in investigating regional tectonic stress fields, source mechanisms and so on.

  6. Assessing the Mental Health Impact of the 2011 Great Japan Earthquake, Tsunami, and Radiation Disaster on Elementary and Middle School Children in the Fukushima Prefecture of Japan.

    PubMed

    Lieber, Mark

    2017-01-01

    On March 11, 2011, a magnitude 9.0 earthquake occurred off of Japan's Pacific coast, which was followed by huge tsunamis that destroyed many coastal cities in the area. Due to the earthquake and subsequent tsunami, malfunctions occurred at the Fukushima Daiichi (Fukushima I) nuclear power plant, resulting in the release of radioactive material in the region. While recent studies have investigated the effects of these events on the mental health of adults in the region, no studies have yet been performed investigating similar effects among children. This study aims to fill that gap by: 1) assessing the mental health of elementary and middle school children living within the Fukushima prefecture of Japan, and 2) identifying risk and protective factors that are associated with the children's mental health scores. These factors were quantified using an original demographics survey, the Strengths and Difficulties Questionnaire (SDQ), and the Impact of Event Scale-Revised (IES-R), the latter two of which have been previously validated in a Japanese setting. The surveys were distributed to approximately 3,650 elementary and middle school students during the months of February and March, 2012. The data suggests that those children who had been relocated to the city of Koriyama had significantly higher SDQ scores than those children who were native to Koriyama (p < .05) as well as a control group that lived outside of the Fukushima prefecture (p < .01). Using a multivariate regression, we also found that younger age and parental trauma were significantly correlated with higher SDQ scores (p < .001), while gender, displacement from one's home, and exposure to violence were not. These results suggest that, among children affected by natural disasters, younger children and those with parents suffering from trauma-related distress are particularly vulnerable to the onset of pediatric mental disturbances.

  7. Assessing the Mental Health Impact of the 2011 Great Japan Earthquake, Tsunami, and Radiation Disaster on Elementary and Middle School Children in the Fukushima Prefecture of Japan

    PubMed Central

    2017-01-01

    Background On March 11, 2011, a magnitude 9.0 earthquake occurred off of Japan’s Pacific coast, which was followed by huge tsunamis that destroyed many coastal cities in the area. Due to the earthquake and subsequent tsunami, malfunctions occurred at the Fukushima Daiichi (Fukushima I) nuclear power plant, resulting in the release of radioactive material in the region. While recent studies have investigated the effects of these events on the mental health of adults in the region, no studies have yet been performed investigating similar effects among children. Methods and Findings This study aims to fill that gap by: 1) assessing the mental health of elementary and middle school children living within the Fukushima prefecture of Japan, and 2) identifying risk and protective factors that are associated with the children’s mental health scores. These factors were quantified using an original demographics survey, the Strengths and Difficulties Questionnaire (SDQ), and the Impact of Event Scale–Revised (IES-R), the latter two of which have been previously validated in a Japanese setting. The surveys were distributed to approximately 3,650 elementary and middle school students during the months of February and March, 2012. The data suggests that those children who had been relocated to the city of Koriyama had significantly higher SDQ scores than those children who were native to Koriyama (p < .05) as well as a control group that lived outside of the Fukushima prefecture (p < .01). Using a multivariate regression, we also found that younger age and parental trauma were significantly correlated with higher SDQ scores (p < .001), while gender, displacement from one’s home, and exposure to violence were not. Conclusions These results suggest that, among children affected by natural disasters, younger children and those with parents suffering from trauma-related distress are particularly vulnerable to the onset of pediatric mental disturbances. PMID:28099497

  8. Location of early aftershocks of the 2004 Mid-Niigata Prefecture Earthquake (M = 6.8) in central Japan using seismogram envelopes as templates

    NASA Astrophysics Data System (ADS)

    Kosuga, M.

    2013-12-01

    The location of early aftershocks is very important to obtain information of mainshock fault, however, it is often difficult due to the long-lasting coda wave of mainshock and successive occurrence of afterrshocks. To overcome this difficulty, we developed a method of location using seismogram envelopes as templates, and applied the method to the early aftershock sequence of the 2004 Mid-Niigata Prefecture (Chuetsu) Earthquake (M = 6.8) in central Japan. The location method composes of three processes. The first process is the calculation of cross-correlation coefficients between a continuous (target) and template envelopes. We prepare envelopes by taking the logarithm of root-mean-squared amplitude of band-pass filtered seismograms. We perform the calculation by shifting the time window to obtain a set of cross-correlation values for each template. The second process is the event detection (selection of template) and magnitude estimate. We search for the events in descending order of cross-correlation in a time window excluding the dead times around the previously detected events. Magnitude is calculated by the amplitude ratio of target and template envelopes. The third process is the relative event location to the selected template. We applied this method to the Chuetsu earthquake, a large inland earthquake with extensive aftershock activity. The number of detected events depends on the number of templates, frequency range, and the threshold value of cross-correlation. We set the threshold as 0.5 by referring to the histogram of cross-correlation. During a period of one-hour from the mainshock, we could detect more events than the JMA catalog. The location of events is generally near the catalog location. Though we should improve the methods of relative location and magnitude estimate, we conclude that the proposed method works adequately even just after the mainshock of large inland earthquake. Acknowledgement: We thank JMA, NIED, and the University of Tokyo for

  9. Source Rupture Process of the 2016 Kumamoto Prefecture, Japan, Earthquake Derived from Near-Source Strong-Motion Records

    NASA Astrophysics Data System (ADS)

    Zheng, A.; Zhang, W.

    2016-12-01

    On 15 April, 2016 the great earthquake with magnitude Mw7.1 occurred in Kumamoto prefecture, Japan. The focal mechanism solution released by F-net located the hypocenter at 130.7630°E, 32.7545°N, at a depth of 12.45 km, and the strike, dip, and the rake angle of the fault were N226°E, 84° and -142° respectively. The epicenter distribution and focal mechanisms of aftershocks implied the mechanism of the mainshock might have changed in the source rupture process, thus a single focal mechanism was not enough to explain the observed data adequately. In this study, based on the inversion result of GNSS and InSAR surface deformation with active structures for reference, we construct a finite fault model with focal mechanism changes, and derive the source rupture process by multi-time-window linear waveform inversion method using the strong-motion data (0.05 1.0Hz) obtained by K-NET and KiK-net of Japan. Our result shows that the Kumamoto earthquake is a right-lateral strike slipping rupture event along the Futagawa-Hinagu fault zone, and the seismogenic fault is divided into a northern segment and a southern one. The strike and the dip of the northern segment are N235°E, 60° respectively. And for the southern one, they are N205°E, 72° respectively. The depth range of the fault model is consistent with the depth distribution of aftershocks, and the slip on the fault plane mainly concentrate on the northern segment, in which the maximum slip is about 7.9 meter. The rupture process of the whole fault continues for approximately 18-sec, and the total seismic moment released is 5.47×1019N·m (Mw 7.1). In addition, the essential feature of the distribution of PGV and PGA synthesized by the inversion result is similar to that of observed PGA and seismic intensity.

  10. INVESTIGATIVE RESEARCH PROJECTS RELATED TO THE TOHOKU EARTHQUAKE (THE GREAT EAST JAPAN EARTHQUAKE) CONDUCTED IN FUKUSHIMA

    PubMed Central

    YAMAMOTO, TOSHIYUKI; HASHIMOTO, YASUHIRO; YOSHIDA, MASAYUKI; OHNO, KIKUO; OHTO, HITOSHI; ABE, MASAFUMI

    2015-01-01

    ABSTRACT Backgrounds: On March 11th 2011, the Tohoku region of Japan was struck by catastrophic disasters. Thousands of people were killed due to a magnitude 9.0 earthquake and its subsequent tsunami. Furthermore, a serious nuclear crisis occurred in Fukushima Prefecture as a result of the disasters, and an emergency evacuation was ordered to people living near the nuclear power plants. There was a lot of anxiety regarding lost families as well as the influences of radioactivity on the health of people and their children. Based on these urgent and uncertain situations, a number of research projects were developed at many institutes both inside and outside Fukushima. Methods: We herein report the investigative research projects related to the Tohoku Earthquake (The Great East Japan Earthquake) conducted after the disasters. The research projects were reviewed by the Institutional Review Board in Fukushima Medical University during the two years following the disasters. The research projects conducted in universities other than Fukushima Medical University were also examined using questionnaire analysis. Results: Among the research projects conducted in Fukushima Medical University (n=424), 7% (n=32) were disaster-related investigative research. The mean duration planned to pursue the projects was 25.5 months. Among these projects, those focusing on the health of Fukushima citizens were most common (n=9), followed by the influence of chronic exposure of radiation on chronic inflammatory disorders (n=6), and the mental health of Fukushima citizens (n=5). They were carefully reviewed for the purpose, suitability, and necessity from ethical as well as scientific viewpoints. The majority of the research projects focused on the effects of the Tohoku Earthquake and/or chronic exposure to low-dose radioactivity on the health of children and pregnant women, as well as on various disorders, such as mental health and chronic inflammatory diseases. On the other hand, among 58

  11. INVESTIGATIVE RESEARCH PROJECTS RELATED TO THE TOHOKU EARTHQUAKE (THE GREAT EAST JAPAN EARTHQUAKE) CONDUCTED IN FUKUSHIMA.

    PubMed

    Yamamoto, Toshiyuki; Hashimoto, Yasuhiro; Yoshida, Masayuki; Ohno, Kikuo; Ohto, Hitoshi; Abe, Masafumi

    2015-01-01

    On March 11(th) 2011, the Tohoku region of Japan was struck by catastrophic disasters. Thousands of people were killed due to a magnitude 9.0 earthquake and its subsequent tsunami. Furthermore, a serious nuclear crisis occurred in Fukushima Prefecture as a result of the disasters, and an emergency evacuation was ordered to people living near the nuclear power plants. There was a lot of anxiety regarding lost families as well as the influences of radioactivity on the health of people and their children. Based on these urgent and uncertain situations, a number of research projects were developed at many institutes both inside and outside Fukushima. We herein report the investigative research projects related to the Tohoku Earthquake (The Great East Japan Earthquake) conducted after the disasters. The research projects were reviewed by the Institutional Review Board in Fukushima Medical University during the two years following the disasters. The research projects conducted in universities other than Fukushima Medical University were also examined using questionnaire analysis. Among the research projects conducted in Fukushima Medical University (n=424), 7% (n=32) were disaster-related investigative research. The mean duration planned to pursue the projects was 25.5 months. Among these projects, those focusing on the health of Fukushima citizens were most common (n=9), followed by the influence of chronic exposure of radiation on chronic inflammatory disorders (n=6), and the mental health of Fukushima citizens (n=5). They were carefully reviewed for the purpose, suitability, and necessity from ethical as well as scientific viewpoints. The majority of the research projects focused on the effects of the Tohoku Earthquake and/or chronic exposure to low-dose radioactivity on the health of children and pregnant women, as well as on various disorders, such as mental health and chronic inflammatory diseases. On the other hand, among 58 projects we collected from 22

  12. Simulation and monitoring tools to protect disaster management facilities against earthquakes

    NASA Astrophysics Data System (ADS)

    Saito, Taiki

    2017-10-01

    The earthquakes that hit Kumamoto Prefecture in Japan on April 14 and 16, 2016 severely damaged over 180,000 houses, including over 8,000 that were completely destroyed and others that were partially damaged according to the Cabinet Office's report as of November 14, 2016 [1]. Following these earthquakes, other parts of the world have been struck by earthquakes including Italy and New Zealand as well as the central part of Tottori Prefecture in October, where the earthquake-induced collapse of buildings has led to severe damage and casualties. The earthquakes in Kumamoto Prefecture, in fact, damaged various disaster management facilities including Uto City Hall, which significantly hindered the city's evacuation and recovery operations. One of the most crucial issues in times of disaster is securing the functions of disaster management facilities such as city halls, hospitals and fire stations. To address this issue, seismic simulations are conducted on the East and the West buildings of Toyohashi City Hall using the analysis tool developed by the author, STERA_3D, with the data of the ground motion waveform prediction for the Nankai Trough earthquake provided by the Ministry of Land, Infrastructure, Transport and Tourism. As the result, it was found that the buildings have sufficient earthquake resistance. It turned out, however, that the west building is at risk for wall cracks or ceiling panel's collapse while in the east building, people would not be able to stand through the strong quakes of 7 on the seismic intensity scale and cabinets not secured to the floors or walls would fall over. Additionally, three IT strong-motion seismometers were installed in the city hall to continuously monitor vibrations. Every five minutes, the vibration data obtained by the seismometers are sent to the computers in Toyohashi University of Technology via the Internet for the analysis tools to run simulations in the cloud. If an earthquake strikes, it is able to use the results

  13. Symptoms of Post-Traumatic Stress Disorder Among Young Children 2 Years After the Great East Japan Earthquake.

    PubMed

    Fujiwara, Takeo; Yagi, Junko; Homma, Hiroaki; Mashiko, Hirofumi; Nagao, Keizo; Okuyama, Makiko

    2017-04-01

    The aim of this study was to investigate the prevalence of post-traumatic stress disorder (PTSD) and its association with each traumatic experience among 5- to 8-year-old children 2 years after the Great East Japan Earthquake. Children ages 5-8 years who were in selected preschool classes on March 11, 2011, in 3 prefectures affected by the earthquake and 1 prefecture that was unaffected, participated in the study (N=280). PTSD symptoms were assessed through questionnaires completed by caregivers and interviews by psychiatrists or psychologists conducted between September 2012 and May 2013 (ie, 1.5-2 years after the earthquake). Among children who experienced the earthquake, 33.8% exhibited PTSD symptoms. Of the different traumatic experiences, experiencing the earthquake and the loss of distant relatives or friends were independently associated with PTSD symptoms; prevalence ratios: 6.88 (95% confidence interval [CI]: 2.06-23.0) and 2.48 (95% CI: 1.21-5.08), respectively. Approximately 1 in 3 young children in the affected communities exhibited PTSD symptoms, even 2 years after the Great East Japan Earthquake. These data may be useful for preventing PTSD symptoms after natural disasters and suggest the importance of providing appropriate mental health services for children. (Disaster Med Public Health Preparedness. 2017;11:207-215).

  14. Relationship between health promotion volunteer experience and medical costs: Hoken-hodouin activities in Suzaka, Nagano.

    PubMed

    Imamura, Haruhiko; Murakami, Yoshitaka; Okamura, Tomonori; Nishiwaki, Yuji

    2017-01-01

    Objectives This study demonstrated the relationship between experience as a health promotion volunteer (Hoken-hodouin) and medical costs in Japan. The study area was Suzaka City (March 2016 population: 51,637) in Nagano Prefecture, Japan, where a total of about 300 women have been engaged and trained as health promotion volunteers since 1958.Methods A cross-sectional survey was conducted in 2014 using a self-administered questionnaire, which included items on experiences as a health promotion volunteer, age at engagement, leadership status, and satisfaction with the experience. Eligible study participants were all residents of Suzaka aged 65 years or over. Medical cost data from April 2013 to March 2014 were collected for women aged 65-74 years who were beneficiaries of the Japanese National Health Insurance (n=2,304). Medical consultation rates and costs for treatment at outpatient and inpatient clinics were analyzed as outcomes. Adjustments were made for age, marital status, educational level, cohabitation status, equivalent income, alcohol use, smoking status, awareness about a healthy diet, and walking time per day.Results Of the 2,304 study participants, 1,274 (55.3%) had experience as health promotion volunteers. Poisson regression analysis revealed that volunteers' experience was positively associated with outpatient care rates (adjusted relative risk [RR]=1.04; 95% confidence interval [CI]=1.02-1.07), and negatively associated with inpatient care rates (RR=0.74; 95% CI=0.56-0.98). Multivariate regression analysis revealed that the adjusted geometric means of outpatient and inpatient care costs were 7% and 23% lower, respectively, among participants with volunteer experience than that among those with no volunteer experience (140,588-151,465 JPY for outpatient costs; 418,457-539,971 JPY for inpatient costs). These associations were stronger among participants who began health promotion volunteer at age 60 years or more, those who had leadership roles

  15. The effects of the Kumamoto earthquake on the clinical symptoms of patients with Parkinson's disease.

    PubMed

    Hori, Hiroko; Kuratomi, Aki; Ishizaki, Masatoshi; Sakamoto, Tetsuro; Nishida, Yasuto; Ando, Yukio

    2017-08-31

    Our hospital is the designated treatment base for intractable neurological diseases in the Kumamoto Prefecture. It is located in the center of the prefecture where the major 7.3-magnitude Kumamoto earthquake was recorded in 2016. In order to examine whether this earthquake affected the clinical symptoms of patients with Parkinson's disease in this hospital, we investigated outpatients examined up to 4 weeks after the earthquake. The subjects were 26 consecutive patients without any changes in anti-Parkinson's disease treatment or their attending physician during the examination period. All of the items in Part III of the Unified Parkinson's Disease Rating Scale (UPDRS), which is a clinician-scored scale for monitoring and evaluating motor function, were confirmed with the subjects before and after the earthquakes. After the earthquakes, worsened symptoms were found in 7 patients and 7 patients felt better. On the UPDRS, worsened symptoms were most commonly found among the items examining "muscle rigidity" and "slowness of movement and decreased movement" among the 7 patients with exacerbated symptoms. After the earthquake, clinical symptoms worsened significantly in women (P = 0.0188), patients with mild symptoms (P = 0.0111), and those who suffered a high degree of personal loss, such as those whose homes were damaged, who were forced to take refuge, or who had to sleep in their car (P = 0.0184). The mental and emotional burden due to the earthquake might be particularly high in the group of patients with worsened symptoms, suggestive of a relationship between stress and the exacerbation of parkinsonian symptoms.

  16. [Chairman's introductory remarks].

    PubMed

    Shimo, Masamune

    2013-01-01

    Remote medicine, as well as the technological development of IT, has been realized in various fields of medical care. Reports have been published of the actual utilization of a system of remote diagnosis by infectious disease surveillance in each region of Nagano Prefecture, a telepathology system in Nagano, operation case of a radiological image remote diagnosis. Situation in the lack of pathologists and radiologists, that changes in the way of working of the physician, or medical information digitized convey how the doctor involved in the diagnosis, any diagnosis based on the information that was received doctor such as whether to perform, various issues have been raised. Soot digitization of information.

  17. The Japan Environment and Children's Study (JECS) in Fukushima Prefecture-A progress report on the enrollment stage.

    PubMed

    Hashimoto, Koichi; Yasumura, Seiji; Fujimori, Keiya; Kyozuka, Hyo; Wakaki, Yu; Sato, Akiko; Hanzawa, Haruko; Yokoyama, Tadahiko; Sato, Testushi; Hosoya, Mitsuaki

    2017-08-09

    The Japan Environment and Children's Study is an ongoing nationwide birth cohort study that is being conducted at 15 regional centers throughout Japan. The recruitment of subjects in the study area within Fukushima Prefecture, which includes Fukushima City, Minami Soma City and Futaba County, was begun on January 31, 2011 with the cooperation of the obstetrics and gynecology departments of local medical institutions. On March 11, soon after the start of recruitment, the Tohoku region was hit by an unprecedented disaster in the shape of the Great East Japan Earthquake, which was closely followed by the Tokyo Electric Power Company's Fukushima Daiichi Nuclear Power Plant accident. As a result of the disaster, the study area in Fukushima Prefecture was expanded on October 1, 2012 to include 59 municipalities across Fukushima Prefecture. Three points are seen as particularly important: 1) Radiation risk communication, 2) The motto is "Be attentive. Be supportive.", and 3) Establishing cooperating partnerships. With the cooperation of all concerned, the recruitment period ended on March 31, 2014. The tentative total number of the participants enrolled at the Fukushima Regional Center was 34,666 (13,134 pregnant mothers, 8,695 fathers and 12,837 children born before November 30, 2014 as of June 2016).

  18. Longitudinal changes in body mass index of children affected by the Great East Japan Earthquake.

    PubMed

    Zheng, W; Yokomichi, H; Matsubara, H; Ishikuro, M; Kikuya, M; Isojima, T; Yokoya, S; Tanaka, T; Kato, N; Chida, S; Ono, A; Hosoya, M; Tanaka, S; Kuriyama, S; Kure, S; Yamagata, Z

    2017-04-01

    The evacuation and disruption in housing caused by the 2011 Great East Japan Earthquake and following nuclear radiation may have influenced child health in many respects. However, studies regarding longitudinal childhood growth are limited. Therefore, in this study we aimed to explore the influence of the earthquake on longitudinal changes in body mass index in preschool children. Participants were children from nursery schools who cooperated with the study in the Iwate, Miyagi and Fukushima prefectures. The exposed group consisted of children who experienced the earthquake during their preschool-age period (4-5 years old). The historical control group included children who were born 2 years earlier than the exposed children in the same prefectures. Trajectories regarding body mass index and prevalence of overweight/obesity were compared between the two groups using multilevel analysis. Differences in the changes in BMI between before and after the earthquake, and proportion of overweight/obesity was compared between the two groups. We also conducted subgroup analysis by defining children with specific personal disaster experiences within the exposed group. A total of 9722 children were included in the study. Children in the exposed group had higher body mass indices and a higher proportion of overweight after the earthquake than the control group. These differences were more obvious when confined to exposed children with specific personal disaster experiences. Children's growth and development-related health issues such as increased BMI after natural disasters should evoke great attention.

  19. The Japan Environment and Children’s Study (JECS) in Fukushima Prefecture-A progress report on the enrollment stage

    PubMed Central

    Hashimoto, Koichi; Yasumura, Seiji; Fujimori, Keiya; Kyozuka, Hyo; Wakaki, Yu; Sato, Akiko; Hanzawa, Haruko; Yokoyama, Tadahiko; Sato, Testushi; Hosoya, Mitsuaki

    2017-01-01

    Abstract The Japan Environment and Children’s Study is an ongoing nationwide birth cohort study that is being conducted at 15 regional centers throughout Japan. The recruitment of subjects in the study area within Fukushima Prefecture, which includes Fukushima City, Minami Soma City and Futaba County, was begun on January 31, 2011 with the cooperation of the obstetrics and gynecology departments of local medical institutions. On March 11, soon after the start of recruitment, the Tohoku region was hit by an unprecedented disaster in the shape of the Great East Japan Earthquake, which was closely followed by the Tokyo Electric Power Company’s Fukushima Daiichi Nuclear Power Plant accident. As a result of the disaster, the study area in Fukushima Prefecture was expanded on October 1, 2012 to include 59 municipalities across Fukushima Prefecture. Three points are seen as particularly important: 1) Radiation risk communication, 2) The motto is “Be attentive. Be supportive.”, and 3) Establishing cooperating partnerships. With the cooperation of all concerned, the recruitment period ended on March 31, 2014. The tentative total number of the participants enrolled at the Fukushima Regional Center was 34,666 (13,134 pregnant mothers, 8,695 fathers and 12,837 children born before November 30, 2014 as of June 2016). PMID:28680007

  20. Estimation of Effective Dose from External Exposure in The Six Prefectures adjacent to Fukushima Prefecture

    NASA Astrophysics Data System (ADS)

    Miyatake, Hirokazu; Yoshizawa, Nobuaki; Hirakawa, Sachiko; Murakami, Kana; Takizawa, Mari; Kawai, Masaki; Sato, Osamu; Takagi, Shunji; Suzuki, Gen

    2017-09-01

    The Fukushima Daiichi Nuclear Power Plant accident caused a release of radionuclides. Radionuclides were deposited on the ground not only in Fukushima prefecture but also in nearby prefectures. Since the accident, measurement of radiation in environment such as air dose rate and deposition density of radionuclides has been performed by many organizations and universities. In particular, Japan Atomic Energy Agency (JAEA) has been performing observations of air dose rate using a car-borne survey system continuously and over wide areas. In our study, using the data measured by JAEA, we estimated effective dose from external exposure in the six prefectures adjacent to Fukushima prefecture. Since car-borne survey was started a few months later after the accident, measured air dose rate in this method is mainly contributed by 137Cs and 134Cs whose half-lives are relatively long. Therefore, based on air dose rate of 137Cs and 134Cs and the ratio of deposition density of short-half-life nuclides to that of 137Cs and 134Cs, we also estimated effective dose contributed from not only 137Cs and 134Cs but also other short-half-life nuclides. We compared the effective dose estimated by the method above with that of UNSCEAR and measured data using personal dosimeters in some areas.

  1. Delayed increase in male suicide rates in tsunami disaster-stricken areas following the great east japan earthquake: a three-year follow-up study in Miyagi Prefecture.

    PubMed

    Orui, Masatsugu; Sato, Yasuhiro; Tazaki, Kanako; Kawamura, Ikuko; Harada, Shuichiro; Hayashi, Mizuho

    2015-03-01

    Devastating natural disasters and their aftermath are known to cause psychological distress. However, little information is available regarding suicide rates following tsunami disasters that destroy regional social services and networks. The aim of the present study was to determine whether the tsunami disaster following the Great East Japan Earthquake in March 2011 has influenced suicide rates. The study period was from March 2009 to February 2014. Tsunami disaster-stricken areas were defined as the 16 municipalities facing the Pacific Ocean in Miyagi Prefecture. Inland areas were defined as other municipalities in Miyagi that were damaged by the earthquake. Suicide rates in the tsunami disaster-stricken areas were compared to national averages, using a time-series analysis and the Poisson distribution test. In tsunami disaster-stricken areas, male suicide rates were significantly lower than the national average during the initial post-disaster period and began to increase after two years. Likewise, male suicide rates in the inland areas decreased for seven months, and then increased to exceed the national average. In contrast, female post-disaster suicide rates did not change in both areas compared to the national average. Importantly, the male suicide rates in the inland areas started to increase earlier compared to the tsunami-stricken areas, which may reflect the relative deficiency of mental healthcare services in the inland areas. Considering the present status that many survivors from the tsunami disaster still live in temporary housing and face various challenges to rebuild their lives, we should continue intensive, long-term mental healthcare services in the tsunami-stricken areas.

  2. Onsite medical rounds and fact-finding activities conducted by Nippon Medical School in Miyagi prefecture after the Great East Japan Earthquake 2011.

    PubMed

    Fuse, Akira; Igarashi, Yutaka; Tanaka, Toshihiko; Kim, Shiei; Tsujii, Atsuko; Kawai, Makoto; Yokota, Hiroyuki

    2011-01-01

    This report describes our onsite medical rounds and fact-finding activities conducted in the acute phase and medical relief work conducted in the subacute phase in Miyagi prefecture following the Great East Japan Earthquake and subsequent tsunami that occurred off northeastern Honshu on March 11, 2011. As part of the All-Japan Hospital Association medical team deployed to the disaster area, a Nippon Medical School team conducted fact-finding and onsite medical rounds and evaluated basic life and medical needs in the affected areas of Shiogama and Tagajo. We performed triage for more than 2,000 casualties, but in our medical rounds of hospitals, clinics, and nursing homes, we found no severely injured person but did find 1 case of hyperglycemia. We conducted medical rounds at evacuation shelters in Kesennuma City during the subacute phase of the disaster, from March 17 through June 1, as part of the Tokyo Medical Association medical teams deployed. Sixty-seven staff members (17 teams), including 46 physicians, 11 nurses, 3 pharmacists, and 1 clinical psychotherapist, joined this mission. Most patients complained of a worsening of symptoms of preexisting conditions, such as hypertension, respiratory problems, and diabetes, rather than of medical problems specifically related to the tsunami. In the acute phase of the disaster, the information infrastructure was decimated and we could not obtain enough information about conditions in the affected areas, such as how many persons were severely injured, how severely lifeline services had been damaged, and what was lacking. To start obtaining this information, we conducted medical rounds. This proved to be a good decision, as we found many injured persons in evacuation shelters without medication, communication devices, or transportation. Also, basic necessities for life, such as water and food, were lacking. We were able to evaluate these basic needs and inform local disaster headquarters of them. In Kesennuma City, we

  3. Induced earthquake during the 2016 Kumamoto earthquake (Mw7.0): Importance of real-time shake monitoring for Earthquake Early Warning

    NASA Astrophysics Data System (ADS)

    Hoshiba, M.; Ogiso, M.

    2016-12-01

    Sequence of the 2016 Kumamoto earthquakes (Mw6.2 on April 14, Mw7.0 on April 16, and many aftershocks) caused a devastating damage at Kumamoto and Oita prefectures, Japan. During the Mw7.0 event, just after the direct S waves passing the central Oita, another M6 class event occurred there more than 80 km apart from the Mw7.0 event. The M6 event is interpreted as an induced earthquake; but it brought stronger shaking at the central Oita than that from the Mw7.0 event. We will discuss the induced earthquake from viewpoint of Earthquake Early Warning. In terms of ground shaking such as PGA and PGV, the Mw7.0 event is much smaller than those of the M6 induced earthquake at the central Oita (for example, 1/8 smaller at OIT009 station for PGA), and then it is easy to discriminate two events. However, PGD of the Mw7.0 is larger than that of the induced earthquake, and its appearance is just before the occurrence of the induced earthquake. It is quite difficult to recognize the induced earthquake from displacement waveforms only, because the displacement is strongly contaminated by that of the preceding Mw7.0 event. In many methods of EEW (including current JMA EEW system), magnitude is used for prediction of ground shaking through Ground Motion Prediction Equation (GMPE) and the magnitude is often estimated from displacement. However, displacement magnitude does not necessarily mean the best one for prediction of ground shaking, such as PGA and PGV. In case of the induced earthquake during the Kumamoto earthquake, displacement magnitude could not be estimated because of the strong contamination. Actually JMA EEW system could not recognize the induced earthquake. One of the important lessons we learned from eight years' operation of EEW is an issue of the multiple simultaneous earthquakes, such as aftershocks of the 2011 Mw9.0 Tohoku earthquake. Based on this lesson, we have proposed enhancement of real-time monitor of ground shaking itself instead of rapid estimation of

  4. Statistical analysis of seismicity rate change in the Tokyo Metropolitan area due to the 2011 Tohoku Earthquake

    NASA Astrophysics Data System (ADS)

    Ishibe, T.; Sakai, S.; Shimazaki, K.; Satake, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.

    2012-12-01

    We examined a relationship between the Coulomb Failure Function (ΔCFF) due to the Tohoku earthquake (March 11, 2011; MJMA 9.0) and the seismicity rate change in Tokyo Metropolitan area following March 2011. Because of large variation in focal mechanism in the Kanto region, the receiver faults for the ΔCFF were assumed to be two nodal planes of small (M ≥ 2.0) earthquakes which occurred before and after the Tohoku earthquake. The seismicity rate changes, particularly the rate increase, are well explained by ΔCFF due to the gigantic thrusting, while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration) may also contribute the rate changes. Among 30,746 previous events provided by the National Research Institute for Earth Science and Disaster Prevention (M ≥ 2.0, July 1979 - July 2003), we used as receiver faults, almost 16,000 events indicate significant increase in ΔCFF, while about 8,000 events show significant decrease. Positive ΔCFF predicts seismicity rate increase in southwestern Ibaraki and northern Chiba prefectures where intermediate-depth earthquakes occur, and in shallow crust of the Izu-Oshima and Hakone regions. In these regions, seismicity rates significantly increased after the Tohoku earthquake. The seismicity has increased since March 2011 with respect to the Epidemic Type of Aftershock Sequence (ETAS) model (Ogata, 1988), indicating that the rate change was due to the stress increase by the Tohoku earthquake. The activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased rate of seismicity in the southwestern Ibaraki and northern Chiba prefectures is still continuing. We also calculated ΔCFF due to the 2011 Tohoku earthquake for the focal mechanism solutions of earthquakes between April 2008 and October 2011 recorded on the Metropolitan Seismic Observation network (MeSO-net). The ΔCFF values for the earthquakes after March 2011 show more

  5. Pregnant Women's Awareness of Social Capital in the Great East Japan Earthquake-Affected Areas of Miyagi Prefecture: The Japan Environment and Children's Study.

    PubMed

    Nishigori, Hidekazu; Nishigori, Toshie; Sakurai, Kasumi; Mizuno, Satoshi; Obara, Taku; Metoki, Hirohito; Watanabe, Zen; Iwama, Noriyuki; Ishikuro, Mami; Tatsuta, Nozomi; Nishijima, Ichiko; Sugawara, Junichi; Kuriyama, Shinichi; Fujiwara, Ikuma; Arima, Takahiro; Nakai, Kunihiko; Takahashi, Fumiaki; Yaegashi, Nobuo

    2017-06-01

    We aimed to clarify the correlation between the 2011 Great East Japan Earthquake and pregnant women's awareness of social capital 3 to 9 months after the tsunami disaster. We analyzed data on responses to a questionnaire by 7451 pregnant women in their second to third trimesters. The proportions of social capital-related items were calculated in the north and south coastal areas of Miyagi Prefecture and were compared with national samples. The factors associated with social capital were estimated by use of multivariate logistic regression analyses. The proportion of women feeling that they had helpful neighbors was higher (69.0% vs 56.7%, P=0.0005), the proportion of women regarding their communities as safe and secure was lower (51.7% vs 62.4%, P=0.002), and the proportion of women feeling that most people were trustworthy was lower (23.7% vs 32.9%, P=0.006) in the north coastal area than nationwide. Such differences were not observed in the less severely affected south coastal area. Age of 35 years or older, extended family, college or university graduation, and being multiparous were associated with the feeling of having helpful neighbors. The current status of pregnant women's awareness of social capital in disaster-affected areas was revealed. Continuous monitoring and support may be necessary to address this issue.(Disaster Med Public Health Preparedness. 2017;11:355-364).

  6. [Cooperation and support activities of infection control after the Great East Japan Earthquake].

    PubMed

    Hatta, Masumitsu; Kaku, Mitsuo

    2013-12-01

    On 11 March 2011, an earthquake measuring 9.0 on the Richter scale occurred off the northeast coast of Honshu Island, Japan, produced a devastating tsunami that destroyed many towns and villages near the coast in Iwate, Miyagi, and Fukushima prefectures. Miyagi Prefecture was the area most severely devastated by the tsunami, with extensive loss of life and property; hundreds of thousands of people lost their houses and were forced to move to evacuation areas. In the days and weeks following devastating natural disasters, the threat of infectious disease outbreak is high. We initiated cooperation and support activities in terms of infection control at evacuation centers in the aftermath of the disaster. For example, we assessed sanitary and infectious risk factors in evacuation centers, in collaboration with Miyagi Prefectural Government and public health centers in the devastated area, to prevent the transmission of infectious diseases among evacuees. We also supported the control of two outbreaks of influenza A, which occurred in different centers in Miyagi Prefecture in the early period after the disaster. Both outbreaks subsided without any complicated or fatal cases of influenza as a result of the prompt implementation of a systemic approach with a bundle of control measures.

  7. Increased prevalence of atrial fibrillation after the Great East Japan Earthquake: Results from the Fukushima Health Management Survey.

    PubMed

    Suzuki, Hitoshi; Ohira, Tetsuya; Takeishi, Yasuchika; Hosoya, Mitsuaki; Yasumura, Seiji; Satoh, Hiroaki; Kawasaki, Yukihiko; Takahashi, Atsushi; Sakai, Akira; Ohtsuru, Akira; Kobashi, Gen; Ozasa, Kotaro; Yamashita, Shunichi; Kamiya, Kenji; Abe, Masafumi

    2015-11-01

    Previous studies have shown that control of cardiovascular risk factors deteriorates among residents after a natural disaster. This study assessed the hypothesis that the prevalence of atrial fibrillation (AF) increased among residents in the evacuation zone of Fukushima prefecture after the Great East Japan Earthquake. This longitudinal study examined subjects aged 40-90 years using data collected from 26,163 participants (11,628 men and 14,535 women) sourced from general health checkups conducted in twelve communities, including the evacuation zone specified by the government, between 2008 and 2010. The study obtained 12-lead ECG tracings and conducted follow-up examinations from June 2011 to the end of March 2013. A total of 12,410 participants (5704 men and 6706 women, follow-up proportion: 47%) received follow-up examinations after the earthquake, with an average follow-up of 1.4 years. The prevalence of AF increased among participants after the earthquake (before: 1.9% vs. after: 2.4%, P<.001). During the follow-up period, 79 incidences of AF occurred among participants. Excess ethanol intake (≥44 g/day) and obesity showed associations with an increased risk of AF after the earthquake, with multivariable-adjusted hazard ratios (95% confidence interval) of 3.07 (1.55-6.08) and 1.87 (1.19-2.94), respectively. The prevalence of AF increased among residents in the evacuation zone of Fukushima prefecture after the Great East Japan Earthquake, with excess alcohol intake and obesity associated with an increased risk of AF. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Radiology diagnostic devices under emergency electric power at disaster base hospitals during the acute phase of the Great East Japan Earthquake: results of a survey of all disaster base hospitals in Miyagi Prefecture.

    PubMed

    Maezawa, Shota; Kudo, Daisuke; Furukawa, Hajime; Nakagawa, Atsuhiro; Yamanouchi, Satoshi; Matsumura, Takashi; Egawa, Shinichi; Tominaga, Teiji; Kushimoto, Shigeki

    2014-12-01

    This study aimed to clarify the management of emergency electric power and the operation of radiology diagnostic devices after the Great East Japan Earthquake. Timing of electricity restoration, actual emergency electric power generation, and whether radiology diagnostic devices were operational and the reason if not were investigated through a questionnaire submitted to all 14 disaster base hospitals in Miyagi Prefecture in February and March 2013. Commercial electricity supply resumed within 3 days after the earthquake at 13 of 14 hospitals. Actual emergency electric power generation was lower than pre-disaster estimates at most of the hospitals. Only 4 of 11 hospitals were able to generate 60% of the power normally consumed. Under emergency electric power, conventional X-ray and computed tomography (CT) scanners worked in 9 of 14 (64%) and 8 of 14 (57%) hospitals, respectively. The main reason conventional X-ray and CT scanners did not operate was that hospitals had not planned to use these devices under emergency electric power. Only 2 of the 14 hospitals had a pre-disaster plan to allocate emergency electric power, and all devices operated at these 2 hospitals. Pre-disaster plans to allocate emergency electric power are required for disaster base hospitals to effectively operate radiology diagnostic devices after a disaster. (Disaster Med Public Health Preparedness. 2014;8:548-552).

  9. Geotechnical aspects of the 2016 MW 6.2, MW 6.0, and MW 7.0 Kumamoto earthquakes

    USGS Publications Warehouse

    Kayen, Robert E.; Dashti, Shideh; Kokusho, T.; Hazarika, H.; Franke, Kevin; Oettle, N. K.; Wham, Brad; Ramirez Calderon, Jenny; Briggs, Dallin; Guillies, Samantha; Cheng, Katherine; Tanoue, Yutaka; Takematsu, Katsuji; Matsumoto, Daisuke; Morinaga, Takayuki; Furuichi, Hideo; Kitano, Yuuta; Tajiri, Masanori; Chaudhary, Babloo; Nishimura, Kengo; Chu, Chu

    2017-01-01

    The 2016 Kumamoto earthquakes are a series of events that began with an earthquake of moment magnitude 6.2 on the Hinagu Fault on April 14, 2016, followed by another foreshock of moment magnitude 6.0 on the Hinagu Fault on April 15, 2016, and a larger moment magnitude 7.0 event on the Futagawa Fault on April 16, 2016 beneath Kumamoto City, Kumamoto Prefecture on Kyushu, Japan. These events are the strongest earthquakes recorded in Kyushu during the modern instrumental era. The earthquakes resulted in substantial damage to infrastructure, buildings, cultural heritage of Kumamoto Castle, roads and highways, slopes, and river embankments due to earthquake-induced landsliding and debris flows. Surface fault rupture produced offset and damage to roads, buildings, river levees, and an agricultural dam. Surprisingly, given the extremely intense earthquake motions, liquefaction occurred only in a few districts of Kumamoto City and in the port areas indicating that the volcanic soils were less susceptible to liquefying than expected given the intensity of earthquake shaking, a significant finding from this event.

  10. Geoengineering and seismological aspects of the Niigata-Ken Chuetsu-Oki earthquake of 16 July 2007

    USGS Publications Warehouse

    Kayen, R.; Brandenberg, S.J.; CoIlins, B.D.; Dickenson, S.; Ashford, S.; Kawamata, Y.; Tanaka, Y.; Koumoto, H.; Abrahamson, N.; Cluff, L.; Tokimatsu, K.

    2009-01-01

    The M6.6 Niigata-Ken Chuetsu-Oki earthquake of 16 July 2007 occurred off the west coast of Japan with a focal depth of 10 km, immediately west of Kashiwazaki City and Kariwa Village in southern Niigata Prefecture. Peak horizontal ground accelerations of 0.68 g were measured in Kashiwazaki City, as well as at the reactor floor level of the world's largest nuclear reactor, located on the coast at Kariwa Village. Liquefaction of historic and modern river deposits, aeolian dune sand, and manmade fill was widespread in the coastal region nearest the epicenter and caused ground deformations that damaged bridges, embankments, roadways, buildings, ports, railways and utilities. Landslides along the coast of southern Niigata Prefecture and in mountainous regions inland of Kashiwazaki were also widespread affecting transportation infrastructure. Liquefaction and a landslide also damaged the nuclear power plant sites. This paper, along with a companion digital map database available at http://walrus.wr.usgs.gOv/infobank/n/nii07jp/html/n-ii-07-jp.sites.kmz, describes the seismological and geo-engineering aspects of the event. ?? 2009, Earthquake Engineering Research Institute.

  11. Increases in seismicity rate in the Tokyo Metropolitan area after the 2011 Tohoku Earthquake

    NASA Astrophysics Data System (ADS)

    Ishibe, T.; Satake, K.; Sakai, S.; Shimazaki, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.

    2013-12-01

    Abrupt increases in seismicity rate have been observed in the Kanto region, where the Tokyo Metropolitan area is located, after the 2011 off the Pacific coast of Tohoku earthquake (M9.0) on March 11, 2011. They are well explained by the static increases in the Coulomb Failure Function (ΔCFF) imparted by the gigantic thrusting while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration, post-seismic slip) may also contribute the rate changes. Because of various types of earthquakes with different focal mechanisms occur in the Kanto region, the receiver faults for the calculation of ΔCFF were assumed to be two nodal planes of small earthquakes before and after the Tohoku earthquake. The regions where seismicity rate increased after the Tohoku earthquake well correlate with concentration on positive ΔCFF (i.e., southwestern Ibaraki and northern Chiba prefectures where intermediate-depth earthquakes occur, and in the shallow crust of western Kanagawa, eastern Shizuoka, and southeastern Yamanashi including the Izu and Hakone regions). The seismicity rate has increased since March 11, 2011 with respect to the Epidemic Type Aftershock Sequence (ETAS) model (Ogata, 1988), suggesting that the rate increase was due to the stress increase by the Tohoku earthquake. Furthermore, the z-values immediately after the Tohoku earthquake show the minimum values during the recent 10 years, indicating significant increases in seismicity rate. At intermediate depth, abrupt increases in thrust faulting earthquakes are well consistent with the Coulomb stress increase. At shallow depth, the earthquakes with the T-axes of roughly NE-SW were activated probably due to the E-W extension of the overriding continental plate, and this is also well explained by the Coulomb stress increase. However, the activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased rate of seismicity in the southwestern

  12. Recovery process of shear wave velocities of volcanic soil in central Mashiki Town after the 2016 Kumamoto earthquake revealed by intermittent measurements of microtremor

    NASA Astrophysics Data System (ADS)

    Hata, Yoshiya; Yoshimi, Masayuki; Goto, Hiroyuki; Hosoya, Takashi; Morikawa, Hitoshi; Kagawa, Takao

    2017-05-01

    An earthquake of JMA magnitude 6.5 (foreshock) hit Kumamoto Prefecture, Japan, at 21:26 JST on April 14, 2016. Subsequently, an earthquake of JMA magnitude 7.3 (main shock) hit Kumamoto and Oita Prefectures at 1:25 JST on April 16, 2016. The two epicenters were located adjacent to central Mashiki Town, and both events caused significantly strong motions. The heavy damage including collapse of residential houses was concentrated in "Sandwich Area" between Prefectural Route 28 and Akitsu River. During the main shock, we have successfully observed strong motions at TMP03 in Sandwich Area. Simultaneously with installation of the seismograph at TMP03 on April 15, 2016, between the foreshock and the main shock, a microtremor measurement was taken. After the main shock, intermittent measurements of microtremor at TMP03 were also taken within December 6, 2016. As the result, recovery process of shear wave velocities of volcanic soil at TMP03 before/after the main shock was revealed by time history of peak frequencies of the microtremor H/V spectra. Using results of original PS logging tests at proximity site of TMP03 on July 28, 2016, the applicability for the shear wave velocities to TMP03 was then confirmed based on similarity between the theoretical and monitored H/V spectra.

  13. Ecological risk assessment of on-site soil washing with iron(III) chloride in cadmium-contaminated paddy field.

    PubMed

    Nagai, Takashi; Horio, Takeshi; Yokoyama, Atsushi; Kamiya, Takashi; Takano, Hiroyuki; Makino, Tomoyuki

    2012-06-01

    On-site soil washing with iron(III) chloride reduces Cd levels in soil, and thus the human health risks caused by Cd in food. However, it may threaten aquatic organisms when soil washing effluent is discharged to open aquatic systems. Therefore, we conducted trial-scale on-site soil washing and ecological risk assessment in Nagano and Niigata prefectures, Japan. The ecological effect of effluent water was investigated by two methods. The first was bioassay using standard aquatic test organisms. Twice-diluted effluent water from the Nagano site and the original effluent water from the Niigata site had no significant effects on green algae, water flea, caddisfly, and fish. The safe dilution rates were estimated as 20 times and 10 times for the Nagano and Niigata sites, respectively, considering an assessment factor of 10. The second method was probabilistic effect analysis using chemical analysis and the species sensitivity distribution concept. The mixture effects of CaCl(2), Al, Zn, and Mn were considered by applying a response additive model. The safe dilution rates, assessed for a potentially affected fraction of species of 5%, were 7.1 times and 23.6 times for the Nagano and Niigata sites, respectively. The actual dilution rates of effluent water by river water at the Nagano and Niigata sites were 2200-67,000 times and 1300-110,000 times, respectively. These are much larger than the safe dilution rates derived from the two approaches. Consequently, the ecological risk to aquatic organisms of soil washing is evaluated as being below the concern level. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Facts about the Eastern Japan Great Earthquake of March 2011

    NASA Astrophysics Data System (ADS)

    Moriyama, T.

    2011-12-01

    The 2011 great earthquake was a magnitude 9.0 Mw undersea megathrust earthquake off the coast of Japan that occurred early morning UTC on Friday, 11 March 2011, with the epicenter approximately 70 kilometres east of the Oshika Peninsula of Tohoku and the hypocenter at an underwater depth of approximately 32 km. It was the most powerful known earthquake to have hit Japan, and one of the five most powerful earthquakes in the world overall since modern record keeping began in 1900. The earthquake triggered extremely destructive tsunami waves of up to 38.9 metres that struck Tohoku Japan, in some cases traveling up to 10 km inland. In addition to loss of life and destruction of infrastructure, the tsunami caused a number of nuclear accidents, primarily the ongoing level 7 meltdowns at three reactors in the Fukushima I Nuclear Power Plant complex, and the associated evacuation zones affecting hundreds of thousands of residents. The Japanese National Police Agency has confirmed 1,5457 deaths, 5,389 injured, and 7,676 people missing across eighteen prefectures, as well as over 125,000 buildings damaged or destroyed. JAXA carried out ALOS emergency observation just after the earthquake occured, and acquired more than 400 scenes over the disaster area. The coseismic interferogram by InSAR analysis cleary showing the epicenter of the earthquake and land surface deformation over Tohoku area. By comparison of before and after satellite images, the large scale damaged area by tunami are extracted. These images and data can access via JAXA website and also GEO Tohoku oki event supersite website.

  15. Reliability of telecommunications systems following a major disaster: survey of secondary and tertiary emergency institutions in Miyagi Prefecture during the acute phase of the 2011 Great East Japan Earthquake.

    PubMed

    Kudo, Daisuke; Furukawa, Hajime; Nakagawa, Atsuhiro; Abe, Yoshiko; Washio, Toshikatsu; Arafune, Tatsuhiko; Sato, Dai; Yamanouchi, Satoshi; Ochi, Sae; Tominaga, Teiji; Kushimoto, Shigeki

    2014-04-01

    Telecommunication systems are important for sharing information among health institutions to successfully provide medical response following disasters. The aim of this study was to clarify the problems associated with telecommunication systems in the acute phase of the Great East Japan Earthquake (March 11, 2011). All 72 of the secondary and tertiary emergency hospitals in Miyagi Prefecture were surveyed to evaluate the telecommunication systems in use during the 2011 Great Japan Earthquake, including satellite mobile phones, multi-channel access (MCA) wireless systems, mobile phones, Personal Handy-phone Systems (PHS), fixed-line phones, and the Internet. Hospitals were asked whether the telecommunication systems functioned correctly during the first four days after the earthquake, and, if not, to identify the cause of the malfunction. Each telecommunication system was considered to function correctly if the hospital staff could communicate at least once in every three calls. Valid responses were received from 53 hospitals (73.6%). Satellite mobile phones functioned correctly at the highest proportion of the equipped hospitals, 71.4%, even on Day 0. The MCA wireless system functioned correctly at the second highest proportion of the equipped hospitals. The systems functioned correctly at 72.0% on Day 0 and at 64.0% during Day 1 through Day 3. The main cause of malfunction of the MCA wireless systems was damage to the base station or communication lines (66.7%). Ordinary (personal or general communication systems) mobile phones did not function correctly at any hospital until Day 2, and PHS, fixed-line phones, and the Internet did not function correctly at any area hospitals that were severely damaged by the tsunami. Even in mildly damaged areas, these systems functioned correctly at <40% of the hospitals during the first three days. The main causes of malfunction were a lack of electricity (mobile phones, 25.6%; the Internet, 54.8%) and damage to the base stations

  16. The Great East-Japan Earthquake and devastating tsunami: an update and lessons from the past Great Earthquakes in Japan since 1923.

    PubMed

    Ishigaki, Akemi; Higashi, Hikari; Sakamoto, Takako; Shibahara, Shigeki

    2013-04-01

    Japan has a long history of fighting against great earthquakes that cause structural damage/collapses, fires and/or tsunami. On March 11, 2011 at 14:46 (Friday), the Great East-Japan Earthquake (magnitude 9.0) attacked the Tohoku region (northeastern Japan), which includes Sendai City. The earthquake generated a devastating tsunami, leading to unprecedented disasters (~18,500 victims) in coastal areas of Iwate, Miyagi and Fukushima prefectures, despite the fact that people living in the Tohoku region are well trained for tsunami-evacuation procedures, with the mindset of "Tsunami, ten-den-ko." This code means that each person should evacuate individually upon an earthquake. Sharing this rule, children and parents can escape separately from schools, houses or workplaces, without worrying about each other. The concept of ten-den-ko (individual evacuation) is helpful for people living in coastal areas of earthquake-prone zones around the world. It is also important to construct safe evacuation centers, because the March 11(th) tsunami killed people who had evacuated to evacuation sites. We summarize the current conditions of people living in the disaster-stricken areas, including the consequences of the Fukushima nuclear accident. We also describe the disaster responses as the publisher of the Tohoku Journal of Experimental Medicine (TJEM), located in Sendai, with online support from Tokyo. In 1923, the Great Kanto Earthquake (magnitude 7.9) evoked a massive fire that destroyed large areas of Tokyo (~105,000 victims), including the print company for TJEM, but the Wistar Institute printed three TJEM issues in 1923 in Philadelphia. Mutual aid relationships should be established between distant cities to survive future disasters.

  17. Design of prospective study of acute coronary syndrome hospitalization after smoking ban in public places in Hyogo prefecture: comparison with Gifu, a prefecture without a public smoking ban.

    PubMed

    Sato, Yukihito; Minatoguchi, Shinya; Nishigaki, Kazuhiko; Hirata, Ken-ichi; Masuyama, Tohru; Furukawa, Yutaka; Uematsu, Masaaki; Yoshikawa, Junichi; Otsuji, Satoru; Iida, Mami; Fujiwara, Hisayoshi

    2014-02-01

    Hyogo is the second prefecture, after Kanagawa, to enact a smoking ban in public places in Japan. The effect of this smoking ban on acute coronary syndrome (ACS) has not been evaluated. Changes in the annual number of ACS hospital cases in Hyogo Prefecture, before and after the enactment of the prefectural legislative ban on smoking in public places, are to be compared with those in Gifu Prefecture, where there is no smoking-ban legislation. Consecutive Hyogo residents with ACS, admitted to 33 major hospitals in the Hanshin-Awaji-Kobe district, which covers 56% of the population, during the 12 months before implementation of the legislation (April 2012 through March 2013) and during the same 24 months thereafter (April 2013 through March 2015) will be enrolled. Consecutive patients with ACS, who are Gifu residents, treated at the 20 major hospitals in Gifu Prefecture will be enrolled as geographical controls. The primary endpoint is the change in number of ACS admissions from April 2012 through March 2015, considering the periods before and after the smoking-ban legislation in Hyogo prefecture. Our study has certain strengths: (1) This is the first large Japanese study of ACS registry with smoking-ban legislation. (2) Major hospitals in the Hanshin-Awaji-Kobe district are included. (3) The data will cover 3 years including 1 year before legislation enactment. (4) The data will be compared with those of Gifu Prefecture, where smoking-ban legislation will not be enacted. (5) The very large database makes possible analysis of subgroups based on age and gender. Copyright © 2013 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  18. Availability, usage, and factors affecting usage of electrophysical agents by physical therapists: a regional cross-sectional survey

    PubMed Central

    Abe, Yuichi; Goh, Ah-Cheng; Miyoshi, Kei

    2016-01-01

    [Purpose] The aim of this study was to investigate the availability, usage, and factors affecting usage of electrophysical agents by physical therapists in Nagano Prefecture, Japan. [Subjects and Methods] Questionnaires were sent to all 1,571 physical therapists working in 245 institutions within Nagano Prefecture. A total of 1,110 questionnaires were returned, out of which 1,099 (70%) questionnaires containing valid responses were analyzed. Frequencies and percentages were calculated for 22 modalities with regards to availability, usage, rate of usage, and confidence level in usage. Factors affecting usage and the relationship between rate of usage and confidence level (Spearman’s rho) were also determined. [Results] The top three responses for the various outcome measures were as follows: (1) hot packs (88%), low frequency stimulators (76%), and ultrasound (68%) for availability; (2) hot packs (72%), ultrasound (61%), and cold packs (59%) for usage; (3) hot packs (75%), cold spray (49%), and ultrasound (44%) for confidence in usage; and (4) equipment availability (80%), past experience (79%), and research evidence (78%) for factors affecting usage. There was a significant positive relationship between confidence and usage for all modalities, except for ultraviolet radiation, iontophoresis, and magnetic field. [Conclusion] Usage was strongly correlated with confidence, with the top three used modalities also being the ones with the highest confidence in usage. PMID:27942126

  19. Comparison of Tsunami height Distributions of the 1960 and the 2010 Chilean Earthquakes on the Coasts of the Japanese Islands

    NASA Astrophysics Data System (ADS)

    Tsuji, Y.; Takahashi, T.; Imai, K.

    2010-12-01

    The tsunami of the Chilean Earthquake (Mw8.8) of February 27, 2010 was detected also on the coasts of the Japanese Islands about 23 hours after the occurrence of the main shock. It caused no human damage. There was slight house damage manly in Miyagi prefecture, south part of Sanriku coast; six and fifty one houses were flooded above and below the floor, respectively. It caused remarkable fishery loss of 75 Million US$ mainly due to breaking of cultivation rafts. The tsunami of the 1960 Chilean Earthquake(Mw9.5) also hit the Japanese coasts more severely. It caused more immense damage than the 2010 tsunami; 142 people were killed, 1,581 houses were entirely destroyed, and 1,256 houses were swept away. Most of damage occurred in the districts of Sanriku coast, where inundation heights exceeded six meters at several points. We made field survey along the Japanese coast, visited offices of fishermen’s cooperatives at over 300 fishery ports, gathered eyewitnesses counts, and obtained information of the inundation limit, arrival time, and building and fishery damage. On the basis of the information of inundation, we measured tsunami heights. We obtained data of tsunami height at more than two hundred points (Tsuji et al., 2010). The distributions of the two tsunamis of the 1960 and the 2010 Chilean earthquakes on the coasts along the Japanese Islands are shown as Fig. 1. The maximum height of 2.2 meters was recorded at Kesennuma City, Miyagi Prefecture. The heights of the 2010 tsunami were generally one third of those of the 1960 tsunami. An eminent peak appears at Sanriku coast commonly for both tsunamis. In addition smaller peaks also appear commonly at the coasts of the east part of Hokkaido, near the top of Boso peninsula, near the top of Izu Peninsula, the east coast of Kii Peninsula, Tokushima prefecture, eastern part of Shikoku, and near the Cape Ashizuri in western part of Shikoku. Fig. 1 Trace height distributions of the tsunamis of the 1960(red) and the 2010

  20. Japanese Experience with Long-term Recovery from the 2011 Tohoku Earthquake and Tsunami Disaster

    NASA Astrophysics Data System (ADS)

    Hayashi, H.

    2015-12-01

    On March 11, 2011, a huge tsunami disaster hit Pacific coast of Tohoku region due to a magnitude of 9.0 earthquake, and killed almost 20,000 people. It was also the beginning of long-term recovery to prepare for next tsunami attack in the future. In this presentation, I would like to review the recovery process from the following five elements: quantification of tsunami hazards, public education, evacuation model, land-use planning, and real-time tsunami warning. It should be noted that there are lessons from the 2011 event at two different levels: national level and prefecture levels. In relation to the quantification of tsunami hazard and real-time tsunami warning, it followed a big change in tsunami policy at national level such as setting up two levels of tsunami scenarios for tsunami preparedness and mitigation: Level 1 tsunami (L1) and Level 2 tsunami (L2). L1 is the tsunami risk with 50 year return period, and L2 is the one with 1,000 year return period. As for public education, evacuation model, and land-use planning, There existed a big difference for what happened in the northern half of the coast and the southern half. Northern half of the coast belongs to Iwate Prefecture whose geography is rias coast. People in the Rias coast of Iwate Prefecture has been hit many times by tsunami on the average of about 50 years. With these many experiences, they succeeded in reducing the number of mortality down to 4,000 in comparison with 20,000 at the 1886 tsunami disaster. Most of the Southern half belongs to Miyagi Prefecture whose geography is coastal plain. People in the coastal plain in Miyagi Prefecture has little experience with tsunami disaster and end up with 14,000 deaths due to tsunami attack. The differences in the past tsunami experiences in these two prefectures resulted in big differences in public education, evacuation model, and land-use planning.

  1. Earthquakes in Oita triggered by the 2016 M7.3 Kumamoto earthquake

    NASA Astrophysics Data System (ADS)

    Yoshida, Shingo

    2016-11-01

    During the passage of the seismic waves from the M7.3 Kumamoto, Kyushu, earthquake on April 16, 2016, a M5.7 [semiofficial value estimated by the Japan Meteorological Agency (JMA)] event occurred in the central part of Oita prefecture, approximately 80 km far away from the mainshock. Although there have been a number of reports that M < 5 earthquakes were remotely triggered during the passage of seismic waves from mainshocks, there has been no evidence for M > 5 triggered events. In this paper, we firstly confirm that this event is a M6-class event by re-estimating the magnitude using the strong-motion records of K-NET and KiK-net, and crustal deformation data at the Yufuin station observed by the Geospatial Information Authority of Japan. Next, by investigating the aftershocks of 45 mainshocks which occurred over the past 20 years based on the JMA earthquake catalog (JMAEC), we found that the delay time of the 2016 M5.7 event in Oita was the shortest. Therefore, the M5.7 event could be regarded as an exceptional M > 5 event that was triggered by passing seismic waves, unlike the usual triggered events and aftershocks. Moreover, a search of the JMAEC shows that in the 2016 Oita aftershock area, swarm earthquake activity was low over the past 30 years compared with neighboring areas. We also found that in the past, probably or possibly triggered events frequently occurred in the 2016 Oita aftershock area. The Oita area readily responds to remote triggering because of high geothermal activity and young volcanism in the area. The M5.7 Oita event was triggered by passing seismic waves, probably because large dynamic stress change was generated by the mainshock at a short distance and because the Oita area was already loaded to a critical stress state without a recent energy release as suggested by the past low swarm activity.[Figure not available: see fulltext.

  2. Changes in suicide rates in disaster-stricken areas following the Great East Japan Earthquake and their effect on economic factors: an ecological study.

    PubMed

    Orui, Masatsugu; Harada, Shuichiro; Hayashi, Mizuho

    2014-11-01

    Devastating disasters may increase suicide rates due to mental distress. Previous domestic studies have reported decreased suicide rates among men following disasters. Few reports are available regarding factors associated with disasters, making it difficult to discuss how these events affect suicide rates. This study aimed to observe changes in suicide rates in disaster-stricken and neighboring areas following the Great East Japan Earthquake, and examine associations between suicide rates and economic factors. Monthly suicide rates were observed from March 2009 to February 2013, during which time the earthquake occurred on March, 2011. Data were included from disaster-stricken (Iwate, Miyagi, and Fukushima Prefectures) and neighboring (control: Aomori, Akita, and Yamagata Prefectures) areas. The association between changes in suicide rates and economic variables was evaluated based on the number of bankruptcy cases and ratio of effective job offers. In disaster-stricken areas, post-disaster male suicide rates decreased during the 24 months following the earthquake. This trend differed relative to control areas. Female suicide rates increased during the first seven months. Multiple regression analysis showed that bankruptcy cases (β = 0.386, p = 0.038) and ratio of effective job offers (β = -0.445, p = 0.018) were only significantly associated with male post-disaster suicide rates in control areas. Post-disaster suicide rates differed by gender following the earthquake. Our findings suggest that considering gender differences might be important for developing future post-disaster suicide prevention measures. This ecological study revealed that increasing effective job offers and decreasing bankruptcy cases can affect protectively male suicide rates in control areas.

  3. The national financial adjustment policy and the equalisation of health levels among prefectures.

    PubMed

    Takano, T; Nakamura, K

    2001-10-01

    The objectives of this study were to examine (1) trends concerning financial assistance from the national government to local governments, (2) trends regarding death rates and life expectancies among prefectures, and (3) the effect of the national financial adjustment policy in equalising both the revenues of local governments and variations in the health levels among prefectures in terms of death rates and life expectancies. The study analysed prefectural income, the amount of national taxes collected, financial assistance from the national government to local governments, and age adjusted death rates and life expectancies of all of the prefectures in Japan during the period from 1965 through 1995. (1) Under the financial adjustment policy, financial assistance from the national government to the local governments, which consists of the sum of the local allocation tax and treasury disbursements, increased from 1831 billion yen in 1965 to 31 116 billion yen in 1995. (2) During the same period, the age adjusted death rate per 100 000 people decreased from 1168.9 (1965) to 545.3 (1995). The range of variation in the age adjusted death rate among prefectures diminished as the coefficient of variation of the death rate declined from 0.060 in 1965 to 0.043 in 1995. (3) There was a significant statistical correlation between higher prefectural incomes and lower mortality rates during from 1965 until 1975 (p < 0.05), whereas this correlation was indistinct in the 1980s and has not been observed since 1990. (4) The relative health level of Tokyo has declined in terms of its ranking among all the prefectures with regard to life expectancy, from being the best in 1965 to below average in 1995. The national financial adjustment policy to balance the revenues of local governments has increased the health levels of rural prefectures. It is probable that the policy reduced the disparity in death rates and life expectancies among prefectures throughout the country. However, the

  4. Impact of the 2011 Great East Japan Earthquake on community health: ecological time series on transient increase in indirect mortality and recovery of health and long-term-care system.

    PubMed

    Uchimura, Mari; Kizuki, Masashi; Takano, Takehito; Morita, Ayako; Seino, Kaoruko

    2014-09-01

    The objectives were to clarify the trend in the cause-specific mortality rate and changes in health and long-term-care use after the Great East Japan Earthquake in 2011. We obtained the following data from national sources: the number of deaths by cause, age and month; the amount of healthcare insurance expenditures by type of services, age and month; the amount of long-term-care insurance expenditures by type of services, age, care need and month. We estimated increase in standardised mortality rate postearthquake compared with pre-earthquake, and change in the standardised amount of health and long-term-care insurance expenditures post-earthquake compared with pre-earthquake in three severely affected prefectures, Iwate, Miyagi and Fukushima, by the adjustment for trends in the other prefectures. The risk of indirect mortality increased in the month of the earthquake (relative risk (RR) with 95% CI 1.20 (1.13 to 1.28) for those 60-69 years of age, 1.25 (1.17 to 1.32) for 70-79 years, and 1.33 (1.27 to 1.38) for 80 years and older). The amount of health and long-term-care insurance expenditures decreased among elderly persons in the month of the earthquake, and recovered to 95% of usual level within 1-5 months. Among cities and towns hit by tsunami, higher percentage of households flooded was associated with higher risk of indirect mortality (p<0.001), lower expenditures for outpatient medical care (p<0.001), and lower expenditures for home-care services (p<0.001). This study showed transient increase in indirect mortality and recovery of health and long-term-care system after the earthquake. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  5. Halley's comet exploration and the Japanese Usuda large antenna

    NASA Technical Reports Server (NTRS)

    Nomura, T.

    1986-01-01

    An overview of the Japanese PLANET-A project to investigate Halley's Comet is given. The objectives and scientific challenges involved in the project are given, and the nature of the contribution made by the large antenna array located at Usuda-Cho, Nagano Prefecture, Japan is discussed. The structural design of the MS-T5 and PLANET-A probes are given, as well as the tracking and control network for the probes. The construction, design, operating system and site selection for the Usuda antenna station are discussed.

  6. Anomalous changes in atmospheric radon concentration before and after the 2011 northern Wakayama Earthquake (Mj 5.5).

    PubMed

    Goto, Mikako; Yasuoka, Yumi; Nagahama, Hiroyuki; Muto, Jun; Omori, Yasutaka; Ihara, Hayato; Mukai, Takahiro

    2017-04-28

    A significant increase in atmospheric radon concentration was observed in the area around the epicentre before and after the occurrence of the shallow inland earthquake in the northern Wakayama Prefecture on 5 July 2011 (Mj 5.5, depth 7 km) in Japan. The seismic activity in the sampling site was evaluated to identify that this earthquake was the largest near the sampling site during the observation period. To determine whether this was an anomalous change, the atmospheric daily minimum radon concentration measured for a 13-year period was analysed. When the residual radon concentration values without the seasonal radon variation and the linear trend was > 3 standard deviations of the residual radon variation corresponding to the normal period, the values were deemed as anomalous. As a result, an anomalous increase in radon concentration was determined before and after the earthquake. In conclusion, anomalous change related to earthquakes with at least Mj 5.5 can be detected by monitoring atmospheric radon near the epicentre. © The Author 2016. Published by Oxford University Press.

  7. Correspondence and challenges as neurologists to Kumamoto Earthquakes in 2016.

    PubMed

    Nakajima, Makoto; Nakane, Nozomi; Takamatsu, Kotaro; Yamashita, Satoshi; Nakane, Shunya; Yamashita, Taro; Ando, Yukio

    2016-12-28

    Kumamoto Earthquakes in 2016 severely affected medical circumstances and condition of each patient with neuro-muscular diseases, in addition to having destroyed life circumstances of local residence. Number of neuro-muscular disease patients admitted to the Department of Neurology, Kumamoto University, the only university hospital in the prefecture, increased approximately twice compared to usual years. Most of the related facilities were able to admit emergency patients with neuro-muscular diseases although the hospital buildings were damaged in various degrees. A number of issues remained unsolved as to emergency contact system, securement of emergency beds for severe neuro-muscular diseases, and information system for these patients.

  8. Geological and seismological survey for new design-basis earthquake ground motion of Kashiwazaki-Kariwa NPS

    NASA Astrophysics Data System (ADS)

    Takao, M.; Mizutani, H.

    2009-05-01

    At about 10:13 on July 16, 2007, a strong earthquake named 'Niigata-ken Chuetsu-oki Earthquake' of Mj6.8 on Japan Meteorological Agencyfs scale occurred offshore Niigata prefecture in Japan. However, all of the nuclear reactors at Kashiwazaki-Kariwa Nuclear Power Station (KKNPS) in Niigata prefecture operated by Tokyo Electric Power Company shut down safely. In other words, automatic safety function composed of shutdown, cooling and containment worked as designed immediately after the earthquake. During the earthquake, the peak acceleration of the ground motion exceeded the design-basis ground motion (DBGM), but the force due to the earthquake applied to safety-significant facilities was about the same as or less than the design basis taken into account as static seismic force. In order to assess anew the safety of nuclear power plants, we have evaluated a new DBGM after conducting geomorphological, geological, geophysical, seismological survey and analyses. [Geomorphological, Geological and Geophysical survey] In the land area, aerial photograph interpretation was performed at least within the 30km radius to extract geographies that could possibly be tectonic reliefs as a geomorphological survey. After that, geological reconnaissance was conducted to confirm whether the extracted landforms are tectonic reliefs or not. Especially we carefully investigated Nagaoka Plain Western Boundary Fault Zone (NPWBFZ), which consists of Kakuda-Yahiko fault, Kihinomiya fault and Katakai fault, because NPWBFZ is the one of the active faults which have potential of Mj8 class in Japan. In addition to the geological survey, seismic reflection prospecting of approximate 120km in total length was completed to evaluate the geological structure of the faults and to assess the consecutiveness of the component faults of NPWBFZ. As a result of geomorphological, geological and geophysical surveys, we evaluated that the three component faults of NPWBFZ are independent to each other from the

  9. Landslide Distribution, Damage and Land Use Interactions During the 2004 Chuetsu Earthquake

    NASA Astrophysics Data System (ADS)

    Sidle, R. C.; Trandafir, A. C.; Kamai, T.

    2005-05-01

    A series of earthquakes struck Niigata Prefecture, Japan, on 23 October 2004 killing about 40 people and injuring about 3000. These earthquakes were characterized by a shallow focal depth (13 km) that generated strong levels of ground motion, resulting in extensive damage and thousands of landslides throughout the region. Most landslides on natural slopes occurred in the regional geological structure consisting of sandy siltstone and thin-bedded alternations of sandstone and siltstone. Earthquakes exacerbate such potential instabilities by the ground motion induced and the enhancement of pore water pressure in wet regoliths. The three strongest earthquakes occurred within a period of less than 40 minutes, and had sequential magnitudes (JMA) of 6.8, 6.3, and 6.5. The highest density of landslides (12/km2) was mapped within a 2.9 km radius of the M6.5 epicenter near Yamakoshi village; about 4 times higher density compared to the other epicenters located to the east and west. This higher density may be a consequence of the cumulative shaking effects associated with the two earlier earthquakes of M6.8 and 6.5, in addition to the topographic and geologic factors controlling the stability of the region. Roads, residential fills, agricultural terraces on hillslopes, and other earthworks increased the susceptibility of sites to slope failure. Numerous earthquake-induced failures in terraces and adjacent hillslopes around rice paddy fields occurred near Yamakoshi village. A housing development in Nagaoka city constructed on an old earthflow suffered from severe damage to fill slopes during the earthquake. Nearly saturated conditions in these deep fills together with poor drainage systems contributed to the landslide damages. Clearly, land use activities in rural and urban areas exacerbated the extent of earthquake-triggered landslides.

  10. Tokyo Metropolitan Earthquake Preparedness Project - A Progress Report

    NASA Astrophysics Data System (ADS)

    Hayashi, H.

    2010-12-01

    Munich Re once ranked that Tokyo metropolitan region, the capital of Japan, is the most vulnerable area for earthquake disasters, followed by San Francisco Bay Area, US and Osaka, Japan. Seismologists also predict that Tokyo metropolitan region may have at least one near-field earthquake with a probability of 70% for the next 30 years. Given this prediction, Japanese Government took it seriously to conduct damage estimations and revealed that, as the worst case scenario, if a7.3 magnitude earthquake under heavy winds as shown in the fig. 1, it would kill a total of 11,000 people and a total of direct and indirect losses would amount to 112,000,000,000,000 yen(1,300,000,000,000, 1=85yen) . In addition to mortality and financial losses, a total of 25 million people would be severely impacted by this earthquake in four prefectures. If this earthquake occurs, 300,000 elevators will be stopped suddenly, and 12,500 persons would be confined in them for a long time. Seven million people will come to use over 20,000 public shelters spread over the impacted area. Over one millions temporary housing units should be built to accommodate 4.6 million people who lost their dwellings. 2.5 million people will relocate to outside of the damaged area. In short, an unprecedented scale of earthquake disaster is expected and we must prepare for it. Even though disaster mitigation is undoubtedly the best solution, it is more realistic that the expected earthquake would hit before we complete this business. In other words, we must take into account another solution to make the people and the assets in this region more resilient for the Tokyo metropolitan earthquake. This is the question we have been tackling with for the last four years. To increase societal resilience for Tokyo metropolitan earthquake, we adopted a holistic approach to integrate both emergency response and long-term recovery. There are three goals for long-term recovery, which consists of Physical recovery, Economic

  11. Radioactive materials deposition in Iwate prefecture, northeast japan, due to the Fukushima dai-ichi nuclear power plant accident.

    NASA Astrophysics Data System (ADS)

    Itoh, Hideyuki

    2013-04-01

    A catastrophic earthquake occurred in March 11, 2011, and additional tsunami gave the big damage along the pacific coastline of the northeast Japan. Tsunami also caused the accident of Fukushima dai-ichi nuclear power plant (FNPP), released of massive amount of radioactive materials to all over the northeast to central Japan. Ministry of Education, cultural, sports, science and technology (MEXT), Japan, carried out the airborne monitoring survey on several times, however, it is impossible to know the deposition of low level radiation under 0.1μSv/h. On the other hand, radioactive material was detected in Iwate by farm and livestock products, and it was necessary to understand an accurate contamination status in Iwate prefecture. Behavior of radioactive material is very similar to the ashfall by the volcanic eruption. Therefore, it is possible to apply the knowledge of volcanology to evaluation of the natural radiation dose. The author carried out the detailed contamination mapping across the Iwate prefecture. To γ-ray measurement, using scintillation counter A2700 of the clearpulse, measured on 1m grass field above ground, for one minute. The total measurement point became more than 800 point whole in Iwate. Field survey were carried out from April to November, 2011, therefore, it is necessary to consider to the half - life of the radioactive element of the cesium 134 and 137. In this study, the author reconstructed a deposition of April, 2011, just after the accident. In addition, the author also carried out the revision of the natural radiation dose included in the granite and so on. From the result, Concentration of radioactive materials depend on the topography, it tend to high concentrate in the basin or along the valley. The feeble deposition 0.01-0.2μsv/h with the radioactive material was recognized in whole prefecture. High contamination area distributed over the E-W directions widely in the southern part of the prefecture, and it also existence of the

  12. How Should Disaster Base Hospitals Prepare for Dialysis Therapy after Earthquakes? Introduction of Double Water Piping Circuits Provided by Well Water System

    PubMed Central

    Ohta, Nobutaka

    2016-01-01

    After earthquakes, continuing dialysis for patients with ESRD and patients suffering from crush syndrome is the serious problem. In this paper, we analyzed the failure of the provision of dialysis services observed in recent disasters and discussed how to prepare for disasters to continue dialysis therapy. Japan has frequently experienced devastating earthquakes. A lot of dialysis centers could not continue dialysis treatment owing to damage caused by these earthquakes. The survey by Japanese Society for Dialysis Treatment (JSDT) after the Great East Japan Earthquake in 2011 showed that failure of lifelines such as electric power and water supply was the leading cause of the malfunction of dialysis treatment. Our hospital is located in Shizuoka Prefecture, where one of the biggest earthquakes is predicted to occur in the near future. In addition to reconstructing earthquake-resistant buildings and facilities, we therefore have adopted double electric and water lifelines by introducing emergency generators and well water supply systems. It is very important to inform politicians, bureaucrats, and local water departments that dialysis treatment, a life sustaining therapy for patients with end stage renal diseases, requires a large amount of water. We cannot prevent an earthquake but can curb the extent of a disaster by preparing for earthquakes. PMID:27999820

  13. How Should Disaster Base Hospitals Prepare for Dialysis Therapy after Earthquakes? Introduction of Double Water Piping Circuits Provided by Well Water System.

    PubMed

    Ikegaya, Naoki; Seki, George; Ohta, Nobutaka

    2016-01-01

    After earthquakes, continuing dialysis for patients with ESRD and patients suffering from crush syndrome is the serious problem. In this paper, we analyzed the failure of the provision of dialysis services observed in recent disasters and discussed how to prepare for disasters to continue dialysis therapy. Japan has frequently experienced devastating earthquakes. A lot of dialysis centers could not continue dialysis treatment owing to damage caused by these earthquakes. The survey by Japanese Society for Dialysis Treatment (JSDT) after the Great East Japan Earthquake in 2011 showed that failure of lifelines such as electric power and water supply was the leading cause of the malfunction of dialysis treatment. Our hospital is located in Shizuoka Prefecture, where one of the biggest earthquakes is predicted to occur in the near future. In addition to reconstructing earthquake-resistant buildings and facilities, we therefore have adopted double electric and water lifelines by introducing emergency generators and well water supply systems. It is very important to inform politicians, bureaucrats, and local water departments that dialysis treatment, a life sustaining therapy for patients with end stage renal diseases, requires a large amount of water. We cannot prevent an earthquake but can curb the extent of a disaster by preparing for earthquakes.

  14. Rare normal faulting earthquake induced by subduction megaquake: example from 2011 Tohoku-oki earthquake

    NASA Astrophysics Data System (ADS)

    Ishiyama, T.; Sugito, N.; Echigo, T.; Sato, H.; Suzuki, T.

    2012-04-01

    A month after March 11 gigantic M9.0 Tohoku-oki earthquake, M7.0 intraplate earthquake occurred at a depth of 5 km on April 11 beneath coastal area of near Iwaki city, Fukushima prefecture. Focal mechanism of the mainshock indicates that this earthquake is a normal faulting event. Based on field reconnaissance and LIDAR mapping by Geospatial Information Authority of Japan, we recognized coseismic surface ruptures, presumably associated with the main shock. Coseismic surface ruptures extend NNW for about 11 km in a right-stepping en echelon manner. Geomorphic expressions of these ruptures commonly include WWS-facing normal fault scarps and/or drape fold scarp with open cracks on their crests, on the hanging wall sides of steeply west-dipping normal fault planes subparallel to Cretaceous metamorphic rocks. Highest topographic scarp height is about 2.3 m. In this study we introduce preliminary results of a trenching survey across the coseismic surface ruptures at Shionohira site, to resolve timing of paleoseismic events along the Shionohira fault. Trench excavations were carried out at two sites (Ichinokura and Shionohira sites) in Iwaki, Fukushima. At Shionohira site a 2-m-deep trench was excavated across the coseismic fault scarp emerged on the alluvial plain on the eastern flank of the Abukuma Mountains. On the trench walls we observed pairs of steeply dipping normal faults that deform Neogene to Paleogene conglomerates and unconformably overlying, late Quaternary to Holocene fluvial units. Sense of fault slip observed on the trench walls (large dip-slip with small sinistral component) is consistent with that estimated from coseismic surface ruptures. Fault throw estimated from separation of piercing points on lower Unit I and vertical structural relief on folded upper Unit I is consistent with topographic height of the coseismic fault scarp at the trench site. In contrast, vertical separation of Unit II, unconformably overlain by Unit I, is measured as about 1.5 m

  15. Psychological recovery 5 years after the 2004 Niigata-Chuetsu earthquake in Yamakoshi, Japan.

    PubMed

    Nakamura, Kazutoshi; Kitamura, Kaori; Someya, Toshiyuki

    2014-01-01

    The 2004 Niigata-Chuetsu earthquake of Japan caused considerable damage. We assessed long-term changes in psychological distress among earthquake victims during the period 5 years after the earthquake. The participants were people aged 18 years or older living in Yamakoshi, a community in Niigata Prefecture near the epicenter. A self-administered questionnaire survey was conducted annually for 5 consecutive years after the earthquake. Response rates were 1316/1841 (71.5%) in 2005, 667/1381 (48.3%) in 2006, 753/1451 (51.9%) in 2007, 541/1243 (43.5%) in 2008, and 814/1158 (70.3%) in 2009. The questionnaire asked about demographic characteristics, including sex, age, employment status, social network, and psychological status. Psychological distress was assessed using the 12-item General Health Questionnaire and was defined as a total score of 4 or higher. The overall prevalence of psychological distress decreased (P < 0.0001) gradually from 2005 (51.0%) to 2008 (30.1%) but tended to increase from 2008 to 2009 (P = 0.1590). Subgroup analyses showed that prevalence did not decrease over the 5-year study period among participants with poor social contact (P = 0.0659). From 2008 to 2009 prevalence increased in women (+7.5%, P = 0.0403) and participants aged 65 years or older (+7.2%, P = 0.0400). The prevalence of psychological distress in Yamakoshi people decreased steadily during the 4 years immediately after the earthquake but appeared to increase thereafter. The earthquake victims are still reestablishing their lives. Thus, continued attention should be focused on maintaining and further assessing their mental health.

  16. Attenuation Characteristics of Strong Motions during the 2016 Kumamoto Earthquakes including Near-Field Records

    NASA Astrophysics Data System (ADS)

    Si, H.; Koketsu, K.; Miyake, H.; Ibrahim, R.

    2016-12-01

    During the two major earthquakes occurred in Kumamoto prefecture, at 21:26 on 14 April, 2016 (Mw 6.2, GCMT), and at 1:25 on 16 April, 2016 (Mw7.0, GCMT), a large number of strong ground motions were recorded, including those very close to the surface fault. In this study, we will discuss the attenuation characteristics of strong ground motions observed during the earthquakes. The data used in this study are mainly observed by K-NET, KiK-net, Osaka University, JMA and Kumamoto prefecture. The 5% damped acceleration response spectra (GMRotI50) are calculated based on the method proposed by Boore et al. (2006). PGA and PGV is defined as the larger one among the PGAs and PGVs of two horizontal components. The PGA, PGV, and GMRotI50 data were corrected to the bedrock with Vs of 1.5km/s based on the method proposed by Si et al. (2016) using the average shear wave velocity (Vs30) and the thickness of sediments over the bedrock. The thickness is estimated based on the velocity structure model provided by J-SHIS. We use a source model proposed by Koketsu et al. (2016) to calculate the fault distance and the median distance (MED) which defined as the closest distance from a station to the median line of the fault plane (Si et al., 2014). We compared the observed PGAs, PGVs, and GMRotI50 with the GMPEs developed in Japan using MED (Si et al., 2014). The predictions by the GMPEs are generally consistent with the observations during the two Kumamoto earthquakes. The results of the comparison also indicated that, (1) strong motion records from the earthquake on April 14th are generally consistent with the predictions by GMPE, however, at the periods of 0.5 to 2 seconds, several records close to the fault plane show larger amplitudes than the predictions by GMPE, including the KiK-net station Mashiki (KMMH16); (2) for the earthquake on April 16, the PGAs and GMRotI50 at periods from 0.1s to 0.4s with short distance from the fault plane are slightly smaller than the predictions by

  17. Design of the health examination survey on early childhood physical growth in the Great East Japan Earthquake affected areas.

    PubMed

    Matsubara, Hiroko; Ishikuro, Mami; Kikuya, Masahiro; Chida, Shoichi; Hosoya, Mitsuaki; Ono, Atsushi; Kato, Noriko; Yokoya, Susumu; Tanaka, Toshiaki; Isojima, Tsuyoshi; Yamagata, Zentaro; Tanaka, Soichiro; Kuriyama, Shinichi; Kure, Shigeo

    2017-03-01

    To investigate the impact of the Great East Japan Earthquake on preschool children's physical growth in the disaster-affected areas, the three medical universities in Iwate, Miyagi, and Fukushima Prefectures conducted a health examination survey on early childhood physical growth. The survey was conducted over a 3-year period to acquire data on children who were born in different years. Our targets were as follows: 1) children who were born between March 1, 2007 and August 31, 2007 and experienced the disaster at 43-48 months of age, 2) children who were born between March 1, 2009 and August 31, 2009 and experienced the disaster at 19-24 months of age, and 3) children who were born between June 1, 2010 and April 30, 2011 and were under 10 months of age or not born yet when the disaster occurred. We collected their health examination data from local governments in Iwate, Miyagi, and Fukushima Prefectures. We also collected data from Aomori, Akita, and Yamagata Prefectures to use as a control group. The survey items included birth information, anthropometric measurements, and methods of nutrition during infancy. Eighty municipalities from Iwate, Miyagi, and Fukushima Prefectures and 21 from the control prefectures participated in the survey. As a result, we established three retrospective cohorts consisting of 13,886, 15,474, and 32,202 preschool children. The large datasets acquired for the present survey will provide valuable epidemiological evidence that should shed light on preschool children's physical growth in relation to the disaster. Copyright © 2016 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  18. A Case Study of the High School Entrance Examination in Chiba Prefecture, Japan.

    ERIC Educational Resources Information Center

    Berman, David M.

    1990-01-01

    Examines the role of the Japanese prefecture (a regional government unit analogous to U.S. states) in school administration through a case study of the Chiba prefectural board of education's role in administering the high school entrance examination. Finds that the examination stratifies students into an educational hierarchy. (NL)

  19. Epidemiology of Epidemic Ebola Virus Disease in Conakry and Surrounding Prefectures, Guinea, 2014-2015.

    PubMed

    Rico, Adriana; Brody, Debra; Coronado, Fátima; Rondy, Marc; Fiebig, Lena; Carcelen, Andrea; Deyde, Varough M; Mesfin, Samuel; Retzer, Kyla D; Bilivogui, Pepe; Keita, Sakoba; Dahl, Benjamin A

    2016-02-01

    In 2014, Ebola virus disease (EVD) in West Africa was first reported during March in 3 southeastern prefectures in Guinea; from there, the disease rapidly spread across West Africa. We describe the epidemiology of EVD cases reported in Guinea's capital, Conakry, and 4 surrounding prefectures (Coyah, Dubreka, Forecariah, and Kindia), encompassing a full year of the epidemic. A total of 1,355 EVD cases, representing ≈40% of cases reported in Guinea, originated from these areas. Overall, Forecariah had the highest cumulative incidence (4× higher than that in Conakry). Case-fatality percentage ranged from 40% in Conakry to 60% in Kindia. Cumulative incidence was slightly higher among male than female residents, although incidences by prefecture and commune differed by sex. Over the course of the year, Conakry and neighboring prefectures became the EVD epicenter in Guinea.

  20. 2014 Anthrax epidemic in Koubia prefecture, Guinea-Conakry.

    PubMed

    Sow, M S; Boushab, M B; Balde, H; Camara, A; Sako, F B; Traoré, F A; Diallo, M O S; Diallo, M D; Keita, M; Sylla, A O; Tounkara, T M; Cissé, M

    2016-11-01

    Anthrax disease is an anthropozoonosis caused by a Gram-positive bacterium, Bacillus anthracis. Our objective was to describe the epidemiological, clinical and therapeutic features of the 2014 epidemic in Koubia prefecture. This retrospective study examined all of the anthrax cases reported in Fafaya, Koubia Prefecture. In March and April 2014, there were 39 cases of human anthrax reported, for an incidence of 1.135%. The mean age was 20.9 (± 18.3) with a sex ratio of 2.54 (28/11) in favor of men. Seventy-six percent (23/39) were single. More than one half were students (53.8%). The main clinical signs were fever in 71, 8% (n = 28 /), papules 59% (n = 23), vesicles of 59% (n = 23) Digestive and cutaneous signs represented 35.9 % and 64.1% respectively; 35% had ingested contaminated meat and 17.95% were in direct contact with a sick animal. We didn't find any correlation between the mode of infection and onset of signs. The fatality rate was 28.21%. The 2014 epidemic of anthrax disease in the Koubia prefecture was marked by a high incidence and lethality. Clinical manifestations were cutaneaous and digestive. These results may serve further interventions to fight against anthrax disease. They should mainly focus on an awareness of peasants, surveillance and vaccination of cattle. Other studies seem to be necessary.

  1. A New Simplified Source Model to Explain Strong Ground Motions from a Mega-Thrust Earthquake - Application to the 2011 Tohoku Earthquake (Mw9.0) -

    NASA Astrophysics Data System (ADS)

    Nozu, A.

    2013-12-01

    A new simplified source model is proposed to explain strong ground motions from a mega-thrust earthquake. The proposed model is simpler, and involves less model parameters, than the conventional characterized source model, which itself is a simplified expression of actual earthquake source. In the proposed model, the spacio-temporal distribution of slip within a subevent is not modeled. Instead, the source spectrum associated with the rupture of a subevent is modeled and it is assumed to follow the omega-square model. By multiplying the source spectrum with the path effect and the site amplification factor, the Fourier amplitude at a target site can be obtained. Then, combining it with Fourier phase characteristics of a smaller event, the time history of strong ground motions from the subevent can be calculated. Finally, by summing up contributions from the subevents, strong ground motions from the entire rupture can be obtained. The source model consists of six parameters for each subevent, namely, longitude, latitude, depth, rupture time, seismic moment and corner frequency of the subevent. Finite size of the subevent can be taken into account in the model, because the corner frequency of the subevent is included in the model, which is inversely proportional to the length of the subevent. Thus, the proposed model is referred to as the 'pseudo point-source model'. To examine the applicability of the model, a pseudo point-source model was developed for the 2011 Tohoku earthquake. The model comprises nine subevents, located off Miyagi Prefecture through Ibaraki Prefecture. The velocity waveforms (0.2-1 Hz), the velocity envelopes (0.2-10 Hz) and the Fourier spectra (0.2-10 Hz) at 15 sites calculated with the pseudo point-source model agree well with the observed ones, indicating the applicability of the model. Then the results were compared with the results of a super-asperity (SPGA) model of the same earthquake (Nozu, 2012, AGU), which can be considered as an

  2. Modeling crustal deformation and rupture processes related to upwelling of deep CO2-rich fluids during the 1965-1967 Matsushiro Earthquake Swarm in Japan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cappa, F.; Rutqvist, J.; Yamamoto, K.

    2009-05-15

    In Matsushiro, central Japan, a series of more than 700,000 earthquakes occurred over a 2-year period (1965-1967) associated with a strike-slip faulting sequence. This swarm of earthquakes resulted in ground surface deformations, cracking of the topsoil, and enhanced spring-outflows with changes in chemical compositions as well as carbon dioxide (CO{sub 2}) degassing. Previous investigations of the Matsushiro earthquake swarm have suggested that migration of underground water and/or magma may have had a strong influence on the swarm activity. In this study, employing coupled multiphase flow and geomechanical modelling, we show that observed crustal deformations and seismicity can have been drivenmore » by upwelling of deep CO{sub 2}-rich fluids around the intersection of two fault zones - the regional East Nagano earthquake fault and the conjugate Matsushiro fault. We show that the observed spatial evolution of seismicity along the two faults and magnitudes surface uplift, are convincingly explained by a few MPa of pressurization from the upwelling fluid within the critically stressed crust - a crust under a strike-slip stress regime near the frictional strength limit. Our analysis indicates that the most important cause for triggering of seismicity during the Matsushiro swarm was the fluid pressurization with the associated reduction in effective stress and strength in fault segments that were initially near critically stressed for shear failure. Moreover, our analysis indicates that a two order of magnitude permeability enhancement in ruptured fault segments may be necessary to match the observed time evolution of surface uplift. We conclude that our hydromechanical modelling study of the Matsushiro earthquake swarm shows a clear connection between earthquake rupture, deformation, stress, and permeability changes, as well as large-scale fluid flow related to degassing of CO{sub 2} in the shallow seismogenic crust. Thus, our study provides further evidence of

  3. Report on Maternal Anxiety 16 Months After the Great East Japan Earthquake Disaster: Anxiety Over Radioactivity

    PubMed Central

    Yoshii, Hatsumi; Saito, Hidemitsu; Kikuchi, Saya; Ueno, Takashi; Sato, Kineko

    2014-01-01

    The Great East Japan Earthquake occurred on March 11, 2011. The tsunami caused extensive damage to the Fukushima Daiichi Nuclear Power Plant, resulting in a level 7 nuclear accident. Among those affected by this combined disaster were many pregnant and parturient women. Sixteen months after the earthquake, we conducted a questionnaire survey on anxiety among 259 women who gave birth around the time of the earthquake in Miyagi Prefecture, one of the affected areas. Participants reported 12 categories of anxiety, including anxiety over radioactivity. This study aimed to determine anxiety over radioactivity among this specific population and to record measures for future study. Anxiety over radiation was classified into seven subcategories: food safety, outdoor safety, effects on the fetuses of pregnant women, effects on children, radiation exposure, economic problems, and distrust of information disclosed. This study confirmed that concrete types of anxiety over radiation were keenly felt by mothers who had experienced the disaster who were currently raising children. The findings suggest the need to provide accurate information to these mothers, who are otherwise inundated with miscellaneous confusing information. PMID:25363115

  4. Report on maternal anxiety 16 months after the great East Japan earthquake disaster: anxiety over radioactivity.

    PubMed

    Yoshii, Hatsumi; Saito, Hidemitsu; Kikuchi, Saya; Ueno, Takashi; Sato, Kineko

    2014-06-25

    The Great East Japan Earthquake occurred on March 11, 2011. The tsunami caused extensive damage to the Fukushima Daiichi Nuclear Power Plant, resulting in a level 7 nuclear accident. Among those affected by this combined disaster were many pregnant and parturient women. Sixteen months after the earthquake, we conducted a questionnaire survey on anxiety among 259 women who gave birth around the time of the earthquake in Miyagi Prefecture, one of the affected areas. Participants reported 12 categories of anxiety, including anxiety over radioactivity. This study aimed to determine anxiety over radioactivity among this specific population and to record measures for future study. Anxiety over radiation was classified into seven subcategories: food safety, outdoor safety, effects on the fetuses of pregnant women, effects on children, radiation exposure, economic problems, and distrust of information disclosed. This study confirmed that concrete types of anxiety over radiation were keenly felt by mothers who had experienced the disaster who were currently raising children. The findings suggest the need to provide accurate information to these mothers, who are otherwise inundated with miscellaneous confusing information.

  5. [Contribution of the rapid diagnostic tests for infectious diseases to the patient management in the Great East Japan earthquake].

    PubMed

    Hatta, Masumitsu; Kaku, Mitsuo

    2012-01-01

    On 11 March 2011, an earthquake measuring 9.0 on the Richter scale off the northeast coast of Honshu Island, Japan, produced a devastating tsunami that destroyed many towns and villages near the coast in Iwate, Miyagi, and Fukushima prefectures. Miyagi Prefecture was the area most severely devastated by the tsunami, with extensive loss of life and property; hundreds of thousands of people lost their houses and were forced to move to evacuation areas. In the days and weeks following devastating natural disasters, the threat of infectious disease outbreak is high. Rapid diagnostic tests can be performed at or near the site of patient care and the tests were very useful in this disaster, because they enabled us to manage patients appropriately in the settings where medical resources were limited. Here we report actual cases where the rapid diagnostic tests for infectious diseases were useful in the patient management.

  6. Psychological Recovery 5 Years After the 2004 Niigata-Chuetsu Earthquake in Yamakoshi, Japan

    PubMed Central

    Nakamura, Kazutoshi; Kitamura, Kaori; Someya, Toshiyuki

    2014-01-01

    Background The 2004 Niigata-Chuetsu earthquake of Japan caused considerable damage. We assessed long-term changes in psychological distress among earthquake victims during the period 5 years after the earthquake. Methods The participants were people aged 18 years or older living in Yamakoshi, a community in Niigata Prefecture near the epicenter. A self-administered questionnaire survey was conducted annually for 5 consecutive years after the earthquake. Response rates were 1316/1841 (71.5%) in 2005, 667/1381 (48.3%) in 2006, 753/1451 (51.9%) in 2007, 541/1243 (43.5%) in 2008, and 814/1158 (70.3%) in 2009. The questionnaire asked about demographic characteristics, including sex, age, employment status, social network, and psychological status. Psychological distress was assessed using the 12-item General Health Questionnaire and was defined as a total score of 4 or higher. Results The overall prevalence of psychological distress decreased (P < 0.0001) gradually from 2005 (51.0%) to 2008 (30.1%) but tended to increase from 2008 to 2009 (P = 0.1590). Subgroup analyses showed that prevalence did not decrease over the 5-year study period among participants with poor social contact (P = 0.0659). From 2008 to 2009 prevalence increased in women (+7.5%, P = 0.0403) and participants aged 65 years or older (+7.2%, P = 0.0400). Conclusions The prevalence of psychological distress in Yamakoshi people decreased steadily during the 4 years immediately after the earthquake but appeared to increase thereafter. The earthquake victims are still reestablishing their lives. Thus, continued attention should be focused on maintaining and further assessing their mental health. PMID:24390416

  7. Psychological distress during pregnancy in Miyagi after the Great East Japan Earthquake: The Japan Environment and Children's Study.

    PubMed

    Watanabe, Zen; Iwama, Noriyuki; Nishigori, Hidekazu; Nishigori, Toshie; Mizuno, Satoshi; Sakurai, Kasumi; Ishikuro, Mami; Obara, Taku; Tatsuta, Nozomi; Nishijima, Ichiko; Fujiwara, Ikuma; Nakai, Kunihiko; Arima, Takahiro; Takeda, Takashi; Sugawara, Junichi; Kuriyama, Shinichi; Metoki, Hirohito; Yaegashi, Nobuo

    2016-01-15

    To examine psychological distress among pregnant women in Miyagi prefecture which was directly affected by the Great East Japan Earthquake and tsunami and compare other areas of Japan that were less damaged. This study was conducted in conjunction with the Japan Environment and Children's Study (JECS). We examined 10,129 Japanese women using the primary fixed data of the JECS. The Kessler 6-item psychological distress scale (K6) was administered to 7473 eligible women including 998 in Miyagi unit center ('Miyagi UC') and 6475 in the other unit centers ('13UCs'). We compared the prevalence and the risk of distress (K6 ≥ 13) during pregnancy in 'Miyagi UC' and '13UCs'. More women in 'Miyagi UC' (4.9%) suffered psychological distress, compared with '13UCs' (3.1%) (p<0.001). A significantly higher prevalence of women in 'Miyagi UC' (55.5%) had experienced negative life events, whereas '13UCs' showed 42.7% (p<0.0001). In multivariable logistic analyses adjusted for baseline characteristics, there was a significant regional difference of psychological distress (adjusted odds ratio; aOR in Miyagi UC=1.488; 95%CI, 1.059-2.090). After further adjusting for negative life events, the association was diminished (aOR=1.338; 95%CI, 0.949-1.884). The JECS had no data before the earthquake and the extent of damage was not investigated. Possible regional representativeness is also a limitation. After the Great East Japan Earthquake, the prevalence of pregnant women with psychological distress (K6 ≥ 13) were high in Miyagi prefecture. Especially in the coastal area directly affected by tsunami, it is high with or without negative life events experienced. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Epidemiology of Epidemic Ebola Virus Disease in Conakry and Surrounding Prefectures, Guinea, 2014–2015

    PubMed Central

    Brody, Debra; Coronado, Fátima; Rondy, Marc; Fiebig, Lena; Carcelen, Andrea; Deyde, Varough M.; Mesfin, Samuel; Retzer, Kyla D.; Bilivogui, Pepe; Keita, Sakoba; Dahl, Benjamin A.

    2016-01-01

    In 2014, Ebola virus disease (EVD) in West Africa was first reported during March in 3 southeastern prefectures in Guinea; from there, the disease rapidly spread across West Africa. We describe the epidemiology of EVD cases reported in Guinea’s capital, Conakry, and 4 surrounding prefectures (Coyah, Dubreka, Forecariah, and Kindia), encompassing a full year of the epidemic. A total of 1,355 EVD cases, representing ≈40% of cases reported in Guinea, originated from these areas. Overall, Forecariah had the highest cumulative incidence (4× higher than that in Conakry). Case-fatality percentage ranged from 40% in Conakry to 60% in Kindia. Cumulative incidence was slightly higher among male than female residents, although incidences by prefecture and commune differed by sex. Over the course of the year, Conakry and neighboring prefectures became the EVD epicenter in Guinea. PMID:26812047

  9. Change in and Long-Term Investigation of Neuro-Otologic Disorders in Disaster-Stricken Fukushima Prefecture: Retrospective Cohort Study before and after the Great East Japan Earthquake

    PubMed Central

    Kuriyama, Shinichi; Obara, Taku; Hashimoto, Ken; Tateda, Yutaka; Okumura, Yuri; Kobayashi, Toshimitsu; Katori, Yukio

    2015-01-01

    On March 11, 2011, Japan’s northeast Pacific coast was hit by a gigantic earthquake and subsequent tsunami. Soma City in Fukushima Prefecture is situated approximately 44 km north of Fukushima Daiichi Nuclear Power Plant. Soma General Hospital is the only hospital in Soma City that provides full-time otolaryngological medical care. We investigated the changes in new patients from one year before to three years after the disaster. We investigated 18,167 new patients treated at our department during the four years from April 1, 2010 to March 31, 2014. Of the new patients, we categorized the diagnoses into Meniere’s disease, acute low-tone sensorineural hearing loss, vertigo, sudden deafness, tinnitus, and facial palsy as neuro-otologic symptoms. We also investigated the changes in the numbers of patients whom we examined at that time concerning other otolaryngological disorders, including epistaxis, infectious diseases of the laryngopharynx, and allergic rhinitis. The total number of new patients did not change remarkably on a year-to-year basis. Conversely, cases of vertigo, Meniere’s disease, and acute low-tone sensorineural hearing loss increased in number immediately after the disaster, reaching a plateau in the second year and slightly decreasing in the third year. Specifically, 4.8% of patients suffering from these neuro-otologic diseases had complications from depression and other mental diseases. With regard to new patients in our department, there was no apparent increase in the number of patients suffering from diseases other than neuro-otologic diseases, including epistaxis, and allergic rhinitis. Patients suffering from vertigo and/or dizziness increased during the first few years after the disaster. These results are attributed to the continuing stress and tension of the inhabitants. This investigation of those living in the disaster area highlights the need for long-term support. PMID:25849607

  10. School-Based Fluoride Mouth-Rinse Program Dissemination Associated With Decreasing Dental Caries Inequalities Between Japanese Prefectures: An Ecological Study.

    PubMed

    Matsuyama, Yusuke; Aida, Jun; Taura, Katsuhiko; Kimoto, Kazunari; Ando, Yuichi; Aoyama, Hitoshi; Morita, Manabu; Ito, Kanade; Koyama, Shihoko; Hase, Akihiro; Tsuboya, Toru; Osaka, Ken

    2016-11-05

    Dental caries inequalities still severely burden individuals' and society's health, even in countries where fluoride toothpastes are widely used and the incidence of dental caries has been decreasing. School-based fluoride mouth-rinse (S-FMR) programs, a population strategy for dental caries prevention, might decrease dental caries inequalities. This study investigated the association between S-FMR and decreasing dental caries prevalence and caries-related inequalities in 12-year-olds by Japanese prefecture. We conducted an ecological study using multi-year prefecture-level aggregated data of children born between 1994 and 2000 in all 47 Japanese prefectures. Using two-level linear regression analyses (birth year nested within prefecture), the association between S-FMR utilization in each prefecture and 12-year-olds' decayed, missing, or filled permanent teeth (DMFT), which indicates dental caries experience in their permanent teeth, were examined. Variables that could explain DMFT inequalities between prefectures, such as dental caries experience at age 3 years, dentist density, and prefectural socioeconomic circumstances, were also considered. High S-FMR utilization was significantly associated with low DMFT at age 12 (coefficient -0.011; 95% confidence interval, -0.018 to -0.005). S-FMR utilization explained 25.2% of the DMFT variance between prefectures after considering other variables. Interaction between S-FMR and dental caries experience at age 3 years showed that S-FMR was significantly more effective in prefectures where the 3-year-olds had high levels of dental caries experience. S-FMR, administered to children of all socioeconomic statuses, was associated with lower DMFT. Utilization of S-FMR reduced dental caries inequalities via proportionate universalism.

  11. Fukushima after the Great East Japan Earthquake: lessons for developing responsive and resilient health systems.

    PubMed

    Fukuma, Shingo; Ahmed, Shahira; Goto, Rei; Inui, Thomas S; Atun, Rifat; Fukuhara, Shunichi

    2017-06-01

    On 11 March 2011, the Great East Japan Earthquake, followed by a tsunami and nuclear-reactor meltdowns, produced one of the most severe disasters in the history of Japan. The adverse impact of this 'triple disaster' on the health of local populations and the health system was substantial. In this study we examine population-level health indicator changes that accompanied the disaster, and discuss options for re-designing Fukushima's health system, and by extension that of Japan, to enhance its responsiveness and resilience to current and future shocks. We used country-level (Japan-average) or prefecture-level data (2005-2014) available from the portal site of Official Statistics of Japan for Fukushima, Miyagi, and Iwate, the prefectures that were most affected by the disaster, to compare trends before (2005-2010) and after (2011-2014) the 'disaster'. We made time-trend line plots to describe changes over time in age-adjusted cause-specific mortality rates in each prefecture. All three prefectures, and in particular Fukushima, had lower socio-economic indicators, an older population, lower productivity and gross domestic product per capita, and less higher-level industry than the Japan average. All three prefectures were 'medically underserved', with fewer physicians, nurses, ambulance calls and clinics per 100 000 residents than the Japan average. Even before the disaster, age-adjusted all-cause mortality in Fukushima was in general higher than the national rates. After the triple disaster we found that the mortality rate due to myocardial infarction increased substantially in Fukushima while it decreased nationwide. Compared to Japan average, spikes in mortality due to lung disease (all three prefectures), stroke (Iwate and Miyagi), and all-cause mortality (Miyagi and Fukushima) were also observed post-disaster. The cause-specific mortality rate from cancer followed similar trends in all three prefectures to those in Japan as a whole. Although we found a sharp

  12. Social Capital Enhanced Disaster Preparedness and Health Consultations after the 2011 Great East Japan Earthquake and Nuclear Power Station Accident

    PubMed Central

    Hasegawa, Makoto; Murakami, Michio; Suzuki, Satoshi; Ohto, Hitoshi

    2018-01-01

    After the Great East Japan Earthquake and the subsequent Fukushima Daiichi Nuclear Power Station accident in 2011, there was a strong demand to promote disaster preparedness approaches and health checkups for the prevention of lifestyle diseases. This study examined the yearly change in the percentage of those who prepared for disasters and who utilized health checkups in Fukushima Prefecture, and identified the factors governing disaster preparedness and utilization of health checkups. We used the public opinion survey from 2011 to 2015 (n = 677–779 each year) on prefectural policies that is conducted every year by the Fukushima Prefecture government Public Consultation Unit. We found that the percentage of those who prepare for disasters decreased, while that for health checkups did not significantly change. With regard to disaster preparedness, experiences of disaster enhance disaster preparedness, while bonds with other local people help to maintain preparedness. For health checkups, familiarity with the welfare service was the most important factor governing such consultations. The findings suggest that social capital should be promoted in order to improve disaster preparedness. The findings also suggest that residents’ accessibility to medical and welfare services is also important in promoting the utilization of health checkups. PMID:29538320

  13. School-Based Fluoride Mouth-Rinse Program Dissemination Associated With Decreasing Dental Caries Inequalities Between Japanese Prefectures: An Ecological Study

    PubMed Central

    Matsuyama, Yusuke; Aida, Jun; Taura, Katsuhiko; Kimoto, Kazunari; Ando, Yuichi; Aoyama, Hitoshi; Morita, Manabu; Ito, Kanade; Koyama, Shihoko; Hase, Akihiro; Tsuboya, Toru; Osaka, Ken

    2016-01-01

    Background Dental caries inequalities still severely burden individuals’ and society’s health, even in countries where fluoride toothpastes are widely used and the incidence of dental caries has been decreasing. School-based fluoride mouth-rinse (S-FMR) programs, a population strategy for dental caries prevention, might decrease dental caries inequalities. This study investigated the association between S-FMR and decreasing dental caries prevalence and caries-related inequalities in 12-year-olds by Japanese prefecture. Methods We conducted an ecological study using multi-year prefecture-level aggregated data of children born between 1994 and 2000 in all 47 Japanese prefectures. Using two-level linear regression analyses (birth year nested within prefecture), the association between S-FMR utilization in each prefecture and 12-year-olds’ decayed, missing, or filled permanent teeth (DMFT), which indicates dental caries experience in their permanent teeth, were examined. Variables that could explain DMFT inequalities between prefectures, such as dental caries experience at age 3 years, dentist density, and prefectural socioeconomic circumstances, were also considered. Results High S-FMR utilization was significantly associated with low DMFT at age 12 (coefficient −0.011; 95% confidence interval, −0.018 to −0.005). S-FMR utilization explained 25.2% of the DMFT variance between prefectures after considering other variables. Interaction between S-FMR and dental caries experience at age 3 years showed that S-FMR was significantly more effective in prefectures where the 3-year-olds had high levels of dental caries experience. Conclusions S-FMR, administered to children of all socioeconomic statuses, was associated with lower DMFT. Utilization of S-FMR reduced dental caries inequalities via proportionate universalism. PMID:27108752

  14. The impact of Japan's 2004 postgraduate training program on intra-prefectural distribution of pediatricians in Japan.

    PubMed

    Sakai, Rie; Wang, Wei; Yamaguchi, Norihiro; Tamura, Hiroshi; Goto, Rei; Kawachi, Ichiro

    2013-01-01

    Inequity in physician distribution poses a challenge to many health systems. In Japan, a new postgraduate training program for all new medical graduates was introduced in 2004, and researchers have argued that this program has increased inequalities in physician distribution. We examined the trends in the geographic distribution of pediatricians as well as all physicians from 1996 to 2010 to identify the impact of the launch of the new training program. The Gini coefficient was calculated using municipalities as the study unit within each prefecture to assess whether there were significant changes in the intra-prefectural distribution of all physicians and pediatricians before and after the launch of the new training program. The effect of the new program was quantified by estimating the difference in the slope in the time trend of the Gini coefficients before and after 2004 using a linear change-point regression design. We categorized 47 prefectures in Japan into two groups: 1) predominantly urban and 2) others by the definition from OECD to conduct stratified analyses by urban-rural status. The trends in physician distribution worsened after 2004 for all physicians (p value<.0001) and pediatricians (p value = 0.0057). For all physicians, the trends worsened after 2004 both in predominantly urban prefectures (p value = 0.0012) and others (p value<0.0001), whereas, for pediatricians, the distribution worsened in others (p value = 0.0343), but not in predominantly urban prefectures (p value =0.0584). The intra-prefectural distribution of physicians worsened after the launch of the new training program, which may reflect the impact of the new postgraduate program. In pediatrics, changes in the Gini trend differed significantly before and after the launch of the new training program in others, but not in predominantly urban prefectures. Further observation is needed to explore how this difference in trends affects the health status of the child population.

  15. Effects of the 2016 Kumamoto earthquakes on the Aso volcanic edifice

    NASA Astrophysics Data System (ADS)

    Tajima, Yasuhisa; Hasenaka, Toshiaki; Torii, Masayuki

    2017-05-01

    Large earthquakes occurred in the central part of Kumamoto Prefecture on April 14-16, 2016, causing severe damage to the northern segment of the Hinagu faults and the eastern segment of the Futagawa faults. Earthquake surface ruptures appeared along these faults and on the Aso volcanic edifice, which in turn generated landslides. We conducted landform change analysis of the central cones of Aso volcano by using satellite and aerial photographs. First, we categorized the topographical changes as surface scarps, arc-shaped cracks, and linear cracks. Field survey indicated that landslides caused the scarps and arc-shaped cracks, whereas faulting caused the linear cracks. We discovered a surface rupture concentration zone (RCZ) formed three ruptures bands with many surface ruptures and landslides extending from the west foot to the center of the Aso volcanic edifice. The magmatic volcanic vents that formed during the past 10,000 years are located along the north margin of the RCZ. Moreover, the distribution and dip of the core of rupture concentration zone correspond with the Nakadake craters. We conclude that a strong relationship exists between the volcanic vents and fault structures in the central cones of Aso volcano.[Figure not available: see fulltext.

  16. [Utilization of Big Data in Medicine and Future Outlook].

    PubMed

    Kinosada, Yasutomi; Uematsu, Machiko; Fujiwara, Takuya

    2016-03-01

    "Big data" is a new buzzword. The point is not to be dazzled by the volume of data, but rather to analyze it, and convert it into insights, innovations, and business value. There are also real differences between conventional analytics and big data. In this article, we show some results of big data analysis using open DPC (Diagnosis Procedure Combination) data in areas of the central part of JAPAN: Toyama, Ishikawa, Fukui, Nagano, Gifu, Aichi, Shizuoka, and Mie Prefectures. These 8 prefectures contain 51 medical administration areas called the second medical area. By applying big data analysis techniques such as k-means, hierarchical clustering, and self-organizing maps to DPC data, we can visualize the disease structure and detect similarities or variations among the 51 second medical areas. The combination of a big data analysis technique and open DPC data is a very powerful method to depict real figures on patient distribution in Japan.

  17. Historical extreme wave and landslide deposits on the Shirasuka coastal lowlands, Shizuoka Prefecture, Japan

    NASA Astrophysics Data System (ADS)

    Garrett, Ed; Riedesel, Svenja; Fujiwara, Osamu; Walstra, Jan; Deforce, Koen; Yokoyama, Yusuke; Schmidt, Sabine; Brill, Dominik; Roberts, Helen; Duller, Geoff; Brückner, Hulmut; De Batist, Marc; Heyvaert, Vanessa

    2017-04-01

    Future megathrust earthquakes and consequential tsunamis pose exceptional hazards to densely populated and highly industrialised coastlines facing the Nankai-Suruga Trough, south central Japan. Geological investigations of coastal sedimentary sequences play a key role in understanding megathrust behaviour and developing seismic and tsunami hazard assessments. In this study, we revisit a previously published palaeoseismic site at Shirasuka, located on the Enshu-nada coastline of Shizuoka Prefecture, seeking both to provide further information on past earthquakes and tsunamis and to explore the prospects and limitations of geological data with respect to assessing seismic and tsunami hazards. At Shirasuka, six closely-spaced vibrocores reveal four sand layers interbedded with organic muds. Photographs, X-ray CT scans and grain size analysis reveal a variety of sedimentary structures within these layers, including abrupt contacts, massive sands, rip-up clasts, internal mud drapes and cross bedding. Microfossil assemblages (diatoms, pollen, non-pollen palynomorphs) and optically stimulated luminescence overdispersion values of single grain feldspars highlight varying sediment sources and transport mechanisms. We suggest that the uppermost sand layer records a landslide from the landward margin of the site, while the remaining three sand layers reflect at least four extreme wave events, some of which are overprinted. We refine the published chronology using AMS radiocarbon, radionuclide and infrared stimulated luminescence approaches. Our Bayesian age models suggest that the oldest two sand layers relate to historically documented tsunamis in AD 1361 and 1498. The second youngest sand layer provides ages consistent with tsunamis in AD 1605 and 1707 and potentially also storm surges in 1680 and/or 1699. The modelled age of the landslide sand layer is consistent with the AD 1944 earthquake. The presence of a fresh scarp in US military aerial photographs from 1947 and

  18. Increasing Incidence of Tuberculosis Infection in the Coastal Region of Northern Miyagi after the Great East Japan Earthquake.

    PubMed

    Sakurai, Masahiro; Takahashi, Tatsuya; Ohuchi, Miyako; Terui, Yuki; Kiryu, Kouji; Shikano, Kazuo

    2016-03-01

    On March 11, 2011, the Great East Japan Earthquake struck off the northeast coast of Japan. Within an hour of the earthquake, devastating tsunamis swept over the coastal region of the Miyagi Prefecture, facing Pacific Ocean. Accordingly, more than 400,000 residents were forced to stay at evacuation shelters. We investigated the changes in tuberculosis prevalence after the disaster. Annual data for all tuberculosis patients between April 1, 2009 and March 31, 2013 were extracted from the database of the Miyagi Prefectural Government. In the coastal region of Northern Miyagi, the number of tuberculosis patients increased in the post-disaster period (p < 0.001, 9.6 vs.19.1 per 100,000 people), compared to the pre-disaster period. In contrast, its prevalence did not change in the inland region of Northern Miyagi and the coastal and inland regions of Southern Miyagi. Importantly, in the inland and coastal regions of Northern Miyagi, the number of patients with latent tuberculosis infection (LTBI) increased in the post-disaster period (p < 0.001). Furthermore, in the coastal shelters, 11 evacuees with the history of contacting tuberculosis patients were diagnosed with LTBI, whereas no cases of LTBI patients were observed in the inland shelters. Thus, staying in the coastal shelters was a risk factor for contracting tuberculosis (OR: 19.31, 95% CI: 1.11-334.80); indeed, twice as many evacuees visited each coastal shelter on April 1, 2011, compared to the inland region. We should prepare the shelters to avoid overcrowding, and long-term observation is required to detect the prevalence of tuberculosis infection.

  19. The Impact of Japan's 2004 Postgraduate Training Program on Intra-Prefectural Distribution of Pediatricians in Japan

    PubMed Central

    Sakai, Rie; Wang, Wei; Yamaguchi, Norihiro; Tamura, Hiroshi; Goto, Rei; Kawachi, Ichiro

    2013-01-01

    Objective Inequity in physician distribution poses a challenge to many health systems. In Japan, a new postgraduate training program for all new medical graduates was introduced in 2004, and researchers have argued that this program has increased inequalities in physician distribution. We examined the trends in the geographic distribution of pediatricians as well as all physicians from 1996 to 2010 to identify the impact of the launch of the new training program. Methods The Gini coefficient was calculated using municipalities as the study unit within each prefecture to assess whether there were significant changes in the intra-prefectural distribution of all physicians and pediatricians before and after the launch of the new training program. The effect of the new program was quantified by estimating the difference in the slope in the time trend of the Gini coefficients before and after 2004 using a linear change-point regression design. We categorized 47 prefectures in Japan into two groups: 1) predominantly urban and 2) others by the definition from OECD to conduct stratified analyses by urban-rural status. Results The trends in physician distribution worsened after 2004 for all physicians (p value<.0001) and pediatricians (p value = 0.0057). For all physicians, the trends worsened after 2004 both in predominantly urban prefectures (p value = 0.0012) and others (p value<0.0001), whereas, for pediatricians, the distribution worsened in others (p value = 0.0343), but not in predominantly urban prefectures (p value = 0.0584). Conclusion The intra-prefectural distribution of physicians worsened after the launch of the new training program, which may reflect the impact of the new postgraduate program. In pediatrics, changes in the Gini trend differed significantly before and after the launch of the new training program in others, but not in predominantly urban prefectures. Further observation is needed to explore how this difference in trends affects

  20. PRESENT CONDITION AND MEASURES TO EXPAND OF VOLUNTARY AGREEMENT ON PLASTIC SHOPPING BAGS REDUCTION AT THE PREFECTURAL LEVEL

    NASA Astrophysics Data System (ADS)

    Mori, Mayuka; Kanaya, Ken

    Purpose of this research is to clear present condition and measures to expand of voluntary agreement on plastic shopping bags reduction at the prefectural level. Methods of this research are questionnaire survey to prefectures implementing the agreement and survey by i town page to the number of stores of companies and the number of companies in the prefectures. Findings of this research are as follows: 1. The refusal rate of plastic shopping bags was 10-40% before the implementation of voluntary agreements. And the rate is approximately 70-90% after the implementation. Therefore, before and after the implementation of voluntary agreements, the refusal rate of plastic shopping bags is approximately 40-70% less. 2. It is suggested that the time and number of meetings from proposal to conclusion of the agreement are related in some way, to the ratio of stores participating. On the participation of administration, the ratio of stores participating in the case in which prefecture and cities participate is higher than in the case in which prefecture participates.

  1. Fukushima after the Great East Japan Earthquake: lessons for developing responsive and resilient health systems

    PubMed Central

    Fukuma, Shingo; Ahmed, Shahira; Goto, Rei; Inui, Thomas S; Atun, Rifat; Fukuhara, Shunichi

    2017-01-01

    Background On 11 March 2011, the Great East Japan Earthquake, followed by a tsunami and nuclear–reactor meltdowns, produced one of the most severe disasters in the history of Japan. The adverse impact of this ‘triple disaster’ on the health of local populations and the health system was substantial. In this study we examine population–level health indicator changes that accompanied the disaster, and discuss options for re–designing Fukushima’s health system, and by extension that of Japan, to enhance its responsiveness and resilience to current and future shocks. Methods We used country–level (Japan–average) or prefecture–level data (2005–2014) available from the portal site of Official Statistics of Japan for Fukushima, Miyagi, and Iwate, the prefectures that were most affected by the disaster, to compare trends before (2005–2010) and after (2011–2014) the ‘disaster’. We made time–trend line plots to describe changes over time in age–adjusted cause–specific mortality rates in each prefecture. Findings All three prefectures, and in particular Fukushima, had lower socio–economic indicators, an older population, lower productivity and gross domestic product per capita, and less higher–level industry than the Japan average. All three prefectures were ‘medically underserved’, with fewer physicians, nurses, ambulance calls and clinics per 100 000 residents than the Japan average. Even before the disaster, age–adjusted all–cause mortality in Fukushima was in general higher than the national rates. After the triple disaster we found that the mortality rate due to myocardial infarction increased substantially in Fukushima while it decreased nationwide. Compared to Japan average, spikes in mortality due to lung disease (all three prefectures), stroke (Iwate and Miyagi), and all–cause mortality (Miyagi and Fukushima) were also observed post–disaster. The cause–specific mortality rate from cancer followed similar trends in

  2. What caused a large number of fatalities in the Tohoku earthquake?

    NASA Astrophysics Data System (ADS)

    Ando, M.; Ishida, M.; Nishikawa, Y.; Mizuki, C.; Hayashi, Y.

    2012-04-01

    The Mw9.0 earthquake caused 20,000 deaths and missing persons in northeastern Japan. 115 years prior to this event, there were three historical tsunamis that struck the region, one of which is a "tsunami earthquake" resulted with a death toll of 22,000. Since then, numerous breakwaters were constructed along the entire northeastern coasts and tsunami evacuation drills were carried out and hazard maps were distributed to local residents on numerous communities. However, despite the constructions and preparedness efforts, the March 11 Tohoku earthquake caused numerous fatalities. The strong shaking lasted three minutes or longer, thus all residents recognized that this is the strongest and longest earthquake that they had been ever experienced in their lives. The tsunami inundated an enormous area at about 560km2 over 35 cities along the coast of northeast Japan. To find out the reasons behind the high number of fatalities due to the March 11 tsunami, we interviewed 150 tsunami survivors at public evacuation shelters in 7 cities mainly in Iwate prefecture in mid-April and early June 2011. Interviews were done for about 30min or longer focused on their evacuation behaviors and those that they had observed. On the basis of the interviews, we found that residents' decisions not to evacuate immediately were partly due to or influenced by earthquake science results. Below are some of the factors that affected residents' decisions. 1. Earthquake hazard assessments turned out to be incorrect. Expected earthquake magnitudes and resultant hazards in northeastern Japan assessed and publicized by the government were significantly smaller than the actual Tohoku earthquake. 2. Many residents did not receive accurate tsunami warnings. The first tsunami warning were too small compared with the actual tsunami heights. 3. The previous frequent warnings with overestimated tsunami height influenced the behavior of the residents. 4. Many local residents above 55 years old experienced

  3. [Contribution of the Department of Laboratory Medicine for the Protection and the Treatment of Diabetes Mellitus in Tokushima Prefecture].

    PubMed

    Noma, Yoshihiko

    2006-09-01

    Diabetes mortality rates of Tokushima prefecture have been worst one in Japan for 12 years. We started up the organization named "Tokushima Medical Doctors Association against Diabetes" for the disease prevention and the improvement of the treatments in Tokushima prefecture. More than 240 medical doctors in Tokushima prefecture joined the association. The activities of the association are ( 1) training of medical doctors, (2) education for co-medical staffs, (3) education and enlightenment for patients and the public, (4) cooperation with Tokushima prefectural medical association and the communities. For the purpose of education for the co-medical staffs, we organized the association of Certified Diabetes Educator of Japan in Tokushima and support the association as the secretariat office. We also work as Tokushima branch office of Japan Association for Diabetes and Education and Care. The prevention of disease and the improvement of medical activity level are one of the big roles those the university hospital is responsible, because the university hospital is anticipated to work as a medical leader in the community. As the University hospital can take care of all medical staffs, so it is thought to be important to contribute the local medical treatment level different with the medical association and prefecture secretariat. The promotion conference for Diabetes mellitus was established last year. The relation among the associations we take care, the local medical association, and the prefecture secretariat are getting better. We hope that our cooperative activities will contribute to reducing morbidity and mortality from diabetes in Tokushima prefecture.

  4. Heat-Related Mortality in Japan after the 2011 Fukushima Disaster: An Analysis of Potential Influence of Reduced Electricity Consumption

    PubMed Central

    Kim, Yoonhee; Gasparrini, Antonio; Honda, Yasushi; Ng, Chris Fook Sheng; Armstrong, Ben

    2017-01-01

    Background: In March 2011, the Great East Japan Earthquake devastated several power stations and caused severe electricity shortages. This accident was followed by the implementation of policies to reduce summer electricity consumption in the affected areas, for example, by limiting air-conditioning (AC) use. This provided a natural experimental scenario to investigate if these policies were associated with an increase in heat-related mortality. Objectives: We examined whether the reduced electricity consumption in warm season modified heat-related mortality from 2008 to 2012. Methods: We conducted prefecture-specific interrupted time-series (ITS) analyses to compare temperature–mortality associations before and after the earthquake, and used meta-analysis to generate combined effect estimates for the most affected and less affected areas (prefectures with >10% or ≤10% reductions in electricity consumption, respectively). We then examined whether the temperature–mortality association in Tokyo, one of the most affected areas, was modified by the percent reduction in electricity consumption relative to expected consumption for comparable days before the earthquake. Results: Contrary to expectations, we estimated a 5–9% reduction in all-cause heat-related mortality after the earthquake in the 15 prefectures with the greatest reduction in electricity consumption, and little change in the other prefectures. However, the percent reduction in observed vs. expected daily electricity consumption after the earthquake did not significantly modify daily heat-related mortality in Tokyo. Conclusions: In the prefectures with the greatest reductions in electricity consumption, heat-related mortality decreased rather than increased following the Great East Japan Earthquake. Additional research is needed to determine whether this finding holds for other populations and regions, and to clarify its implications for policies to reduce the consequences of climate change on

  5. Heat-Related Mortality in Japan after the 2011 Fukushima Disaster: An Analysis of Potential Influence of Reduced Electricity Consumption.

    PubMed

    Kim, Yoonhee; Gasparrini, Antonio; Hashizume, Masahiro; Honda, Yasushi; Ng, Chris Fook Sheng; Armstrong, Ben

    2017-07-06

    In March 2011, the Great East Japan Earthquake devastated several power stations and caused severe electricity shortages. This accident was followed by the implementation of policies to reduce summer electricity consumption in the affected areas, for example, by limiting air-conditioning (AC) use. This provided a natural experimental scenario to investigate if these policies were associated with an increase in heat-related mortality. We examined whether the reduced electricity consumption in warm season modified heat-related mortality from 2008 to 2012. We conducted prefecture-specific interrupted time-series (ITS) analyses to compare temperature-mortality associations before and after the earthquake, and used meta-analysis to generate combined effect estimates for the most affected and less affected areas (prefectures with >10% or ≤10% reductions in electricity consumption, respectively). We then examined whether the temperature-mortality association in Tokyo, one of the most affected areas, was modified by the percent reduction in electricity consumption relative to expected consumption for comparable days before the earthquake. Contrary to expectations, we estimated a 5-9% reduction in all-cause heat-related mortality after the earthquake in the 15 prefectures with the greatest reduction in electricity consumption, and little change in the other prefectures. However, the percent reduction in observed vs. expected daily electricity consumption after the earthquake did not significantly modify daily heat-related mortality in Tokyo. In the prefectures with the greatest reductions in electricity consumption, heat-related mortality decreased rather than increased following the Great East Japan Earthquake. Additional research is needed to determine whether this finding holds for other populations and regions, and to clarify its implications for policies to reduce the consequences of climate change on health. https://doi.org/10.1289/EHP493.

  6. [Association between evacuation condition and habitual physical activity in Great East Japan Earthquake evacuees: The Fukushima Health Management Survey].

    PubMed

    Nagai, Masato; Ohira, Tetsuya; Yasumura, Seiji; Takahashi, Hideto; Yuki, Michiko; Nakano, Hironori; Wen, Zhang; Yabe, Hirooki; Ohtsuru, Akira; Maeda, Masaharu; Takase, Kanae

    2016-01-01

    Objectives: Prevalence of life-style disease has increased dramatically in evacuees due to the Great East Japan Earthquake. One reason may be that physical activity level decreased from life environment changes due to evacuation. However, associations between evacuation condition and habitual physical activity have not been studied. We examined this association in Fukushima residents who participated in the Fukushima Health Management Survey. Methods: In this study, 37,843 evacuees from 13 municipal evacuation zones from the nuclear-power accident caused by the Great East Japan Earthquake, born before April 1, 1995, were included in the analysis. Evacuation condition was defined by disaster living place (13 zones), evacuation place (inside or outside the prefecture), and current living status (evacuation shelter or temporary housing, rental housing/ apartment, and relative's home or own home). Habitual physical activity was defined from self-administered questionnaires as participants who responded "almost every day" and "2-4 times/week" of regular exercise. In the analysis, habitual physical activity prevalence was aggregated by gender and variables (living place in the disaster, evacuation place, and current living status). Prevalence was adjusted for age, disaster living place, evacuation place, and current living status by standard analysis of covariance methods. Results: Adjusted prevalences of habitual physical activity were: men, 27.9-46.5%; women, 27.0-43.7% in each disaster living place. The differences were 18.6% point in men and 16.7% point in women. For evacuation place, physical activity outside the prefecture for men (37.7%) and inside the prefecture for women (32.1%) were higher, but those differences were only 2.2% point and 1.8% point in men and women, respectively. For current living status, physical activity of those in rental housing/ apartment was the lowest; evacuation shelter or temporary housing was the highest in both genders (men: 38

  7. Population size dependency of measles epidemic that was scalable from Japanese prefectures to European countries.

    PubMed

    Yoshikura, Hiroshi

    2018-04-27

    Relation between number of measles patients (y) and population size (x) was expressed by an equation y = ax s , where a is a constant and s the slope of the plot; s was 2.04-2.17 for prefectures in Japan, i.e., the number of patients was proportional to square of the prefecture population size. For European countries that joined European Union no later than 2009, the slope was 1.43-1.87. The measles' population dependency found among prefectures in Japan was thus scalable up to European countries. It was surprising because, unlike Japan, population density in EU countries was not uniform and not proportional to the population size. The population size dependency was not observed among Western Pacific and South-East Asian countries probably on account of confounding interacting socioeconomic factors. Correlation between measles incidence and birth rate, infant mortality or GDP per capita was almost insignificant.Size distribution of local infection clusters (LICs) of measles and rubella in Japan followed power law. For measles, though the population dependency remained unchanged after "elimination", there was change in the Zipf-type plot of LIC sizes. After the "elimination", LICs linked to importation-related outbreaks in less populated prefectures emerged as the top-ranked LICs.

  8. First Observation of Coseismic Seafloor Crustal Deformation due to M7 Class Earthquakes in the Philippine Sea Plate

    NASA Astrophysics Data System (ADS)

    Tadokoro, K.; Ikuta, R.; Ando, M.; Okuda, T.; Sugimoto, S.; Besana, G. M.; Kuno, M.

    2005-12-01

    The Mw7.3 and 7.5 earthquakes (Off Kii-Peninsula Earthquakes) occurred close to the source region of the anticipated Tonankai Trough in September 5, 2004. The focal mechanisms of the two earthquakes have no low angle nodal planes, which shows that the earthquakes are intraplate earthquakes in the Philippine Sea Plate. We observed coseismic horizontal displacement due to the Off Kii-Peninsula Earthquakes by means of a system for observing seafloor crustal deformation, which is the first observation of coseismic seafloor displacement in the world. We have developed a system for observing seafloor crustal deformation. The observation system is composed of 1) acoustic measurement between a ship transducer and sea-bottom transponders, and 2) kinematic GPS positioning of the observation vessel. We have installed a seafloor benchmark close to the epicenters of the Off Kii-Peninsula Earthquakes. The benchmark is composed of three sea-bottom transponders. The location of benchmark is defined as the weight center of the three transponders. We can determine the location of benchmark with an accuracy of about 5 cm at each observation. We have repeatedly measured the seafloor benchmark six times up to now: 1) July 12-16 and 21-22, 2004, 2) November 9-10, 3) January 19, 2005, 4) May 18-20, 5) July 19-20, and 6) August 18-19 and 29-30. The Off Kii-Peninsula Earthquakes occurred during the above monitoring period. The coseismic horizontal displacement of about 21 cm toward SSE was observed at our seafloor benchmark. The displacement is 3.5 times as large as the maximum displacement observed by on land GPS network in Japan, GEONET. The monitoring of seafloor crustal deformation is effective to detect the deformations associated with earthquakes occurring in ocean areas. This study is promoted by "Research Revolution 2002" of Ministry of Education, Culture, Sports, Science and Technology, Japan. We are grateful to the captain and crews of Research Vessel, Asama, of Mie Prefectural

  9. Probabilistic tsunami hazard assessment based on the long-term evaluation of subduction-zone earthquakes along the Sagami Trough, Japan

    NASA Astrophysics Data System (ADS)

    Hirata, K.; Fujiwara, H.; Nakamura, H.; Osada, M.; Ohsumi, T.; Morikawa, N.; Kawai, S.; Maeda, T.; Matsuyama, H.; Toyama, N.; Kito, T.; Murata, Y.; Saito, R.; Takayama, J.; Akiyama, S.; Korenaga, M.; Abe, Y.; Hashimoto, N.; Hakamata, T.

    2017-12-01

    For the forthcoming large earthquakes along the Sagami Trough where the Philippine Sea Plate is subducting beneath the northeast Japan arc, the Earthquake Research Committee(ERC) /Headquarters for Earthquake Research Promotion, Japanese government (2014a) assessed that M7 and M8 class earthquakes will occur there and defined the possible extent of the earthquake source areas. They assessed 70% and 0% 5% of the occurrence probability within the next 30 years (from Jan. 1, 2014), respectively, for the M7 and M8 class earthquakes. First, we set possible 10 earthquake source areas(ESAs) and 920 ESAs, respectively, for M8 and M7 class earthquakes. Next, we constructed 125 characterized earthquake fault models (CEFMs) and 938 CEFMs, respectively, for M8 and M7 class earthquakes, based on "tsunami receipt" of ERC (2017) (Kitoh et al., 2016, JpGU). All the CEFMs are allowed to have a large slip area for expression of fault slip heterogeneity. For all the CEFMs, we calculate tsunamis by solving a nonlinear long wave equation, using FDM, including runup calculation, over a nesting grid system with a minimum grid size of 50 meters. Finally, we re-distributed the occurrence probability to all CEFMs (Abe et al., 2014, JpGU) and gathered excess probabilities for variable tsunami heights, calculated from all the CEFMs, at every observation point along Pacific coast to get PTHA. We incorporated aleatory uncertainties inherent in tsunami calculation and earthquake fault slip heterogeneity. We considered two kinds of probabilistic hazard models; one is "Present-time hazard model" under an assumption that the earthquake occurrence basically follows a renewal process based on BPT distribution if the latest faulting time was known. The other is "Long-time averaged hazard model" under an assumption that earthquake occurrence follows a stationary Poisson process. We fixed our viewpoint, for example, on the probability that the tsunami height will exceed 3 meters at coastal points in next

  10. Regional differences in population-based cancer survival between six prefectures in Japan: application of relative survival models with funnel plots.

    PubMed

    Ito, Yuri; Ioka, Akiko; Tsukuma, Hideaki; Ajiki, Wakiko; Sugimoto, Tomoyuki; Rachet, Bernard; Coleman, Michel P

    2009-07-01

    We used new methods to examine differences in population-based cancer survival between six prefectures in Japan, after adjustment for age and stage at diagnosis. We applied regression models for relative survival to data from population-based cancer registries covering each prefecture for patients diagnosed with stomach, lung, or breast cancer during 1993-1996. Funnel plots were used to display the excess hazard ratio (EHR) for each prefecture, defined as the excess hazard of death from each cancer within 5 years of diagnosis relative to the mean excess hazard (in excess of national background mortality by age and sex) in all six prefectures combined. The contribution of age and stage to the EHR in each prefecture was assessed from differences in deviance-based R(2) between the various models. No significant differences were seen between prefectures in 5-year survival from breast cancer. For cancers of the stomach and lung, EHR in Osaka prefecture were above the upper 95% control limits. For stomach cancer, the age- and stage-adjusted EHR in Osaka were 1.29 for men and 1.43 for women, compared with Fukui and Yamagata. Differences in the stage at diagnosis of stomach cancer appeared to explain most of this excess hazard (61.3% for men, 56.8% for women), whereas differences in age at diagnosis explained very little (0.8%, 1.3%). This approach offers the potential to quantify the impact of differences in stage at diagnosis on time trends and regional differences in cancer survival. It underlines the utility of population-based cancer registries for improving cancer control.

  11. Connecting slow earthquakes to huge earthquakes.

    PubMed

    Obara, Kazushige; Kato, Aitaro

    2016-07-15

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes. Copyright © 2016, American Association for the Advancement of Science.

  12. The lack of antiepileptic drugs and worsening of seizures among physically handicapped patients with epilepsy during the Great East Japan Earthquake.

    PubMed

    Kobayashi, Satoru; Endo, Wakaba; Inui, Takehiko; Wakusawa, Keisuke; Tanaka, Soichiro; Onuma, Akira; Haginoya, Kazuhiro

    2016-08-01

    Takuto Rehabilitation Center for Children is located in Sendai, the capital of the Miyagi prefecture, and faces the Pacific Ocean. The tsunami caused by the Great East Japan Earthquake resulted in tremendous damage to this region. Many physically handicapped patients with epilepsy who are treated at our hospital could not obtain medicine. We surveyed patients with epilepsy, using a questionnaire to identify the problems during the acute phase of the Great East Japan Earthquake. After the earthquake, we mailed questionnaires to physically handicapped patients with epilepsy who are treated and prescribed medications at our hospital, or to their parents. A total of 161 respondents completed the questionnaire. Overall, 68.4% of patients had seven days or less of stockpiled medication when the earthquake initially struck, and 28.6% of patients had no medication or almost no medication during the acute phase after the earthquake. Six patients were forced to stop taking their medication and nine patients experienced a worsening of seizures. Most (93.6%) patients stated they require a stockpile of medication for more than seven days: 20months after the earthquake, 76.9% patients a supply of drugs for more than seven days. We suggest that physically handicapped patients with epilepsy are recommended to prepare for natural disasters by stockpiling additional medication. Even if the stock of antiepileptic drugs is sufficient, stress could cause worsening of seizures. Specialized support is required after a disaster among physically handicapped patients with epilepsy. Copyright © 2016 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  13. Geographical structures and the cholera epidemic in modern Japan: Fukushima prefecture in 1882 and 1895.

    PubMed

    Kuo, Chun-Lin; Fukui, Hiromichi

    2007-06-30

    Disease diffusion patterns can provide clues for understanding geographical change. Fukushima, a rural prefecture in northeast Japan, was chosen for a case study of the late nineteenth century cholera epidemic that occurred in that country. Two volumes of Cholera Ryu-ko Kiji (Cholera Epidemic Report), published by the prefectural government in 1882 and 1895, provide valuable records for analyzing and modelling diffusion. Text descriptions and numerical evidence culled from the reports were incorporated into a temporal-spatial study framework using geographic information system (GIS) and geo-statistical techniques. Changes in diffusion patterns between 1882 and 1895 reflect improvements in the Fukushima transportation system and growth in social-economic networks. The data reveal different diffusion systems in separate regions in which residents of Fukushima and neighboring prefectures interacted. Our model also shows that an area in the prefecture's northern interior was dominated by a mix of diffusion processes (contagious and hierarchical), that the southern coastal region was affected by a contagious process, and that other infected areas experienced relocation diffusion. In addition to enhancing our understanding of epidemics, the spatial-temporal patterns of cholera diffusion offer opportunities for studying regional change in modern Japan. By highlighting the dynamics of regional reorganization, our findings can be used to better understand the formation of an urban hierarchy in late nineteenth century Japan.

  14. The susceptibility analysis of landslides induced by earthquake in Aso volcanic area, Japan, scoping the prediction

    NASA Astrophysics Data System (ADS)

    Kubota, Tetsuya; Takeda, Tsuyoshi

    2017-04-01

    Kumamoto earthquake on April 16th 2016 in Kumamoto prefecture, Kyushu Island, Japan with intense seismic scale of M7.3 (maximum acceleration = 1316 gal in Aso volcanic region) yielded countless instances of landslide and debris flow that induced serious damages and causalities in the area, especially in the Aso volcanic mountain range. Hence, field investigation and numerical slope stability analysis were conducted to delve into the characteristics or the prediction factors of the landslides induced by this earthquake. For the numerical analysis, Finite Element Method (FEM) and CSSDP (Critical Slip Surface analysis by Dynamic Programming theory based on limit equilibrium method) were applied to the landslide slopes with seismic acceleration observed. These numerical analysis methods can automatically detect the landslide slip surface which has minimum Fs (factor of safety). The various results and the information obtained through this investigation and analysis were integrated to predict the landslide susceptible slopes in volcanic area induced by earthquakes and rainfalls of their aftermath, considering geologic-geomorphologic features, geo-technical characteristics of the landslides and vegetation effects on the slope stability. Based on the FEM or CSSDP results, the landslides occurred in this earthquake at the mild gradient slope on the ridge have the safety factor of slope Fs=2.20 approximately (without rainfall nor earthquake, and Fs>=1.0 corresponds to stable slope without landslide) and 1.78 2.10 (with the most severe rainfall in the past) while they have approximately Fs=0.40 with the seismic forces in this earthquake (horizontal direction 818 gal, vertical direction -320 gal respectively, observed in the earthquake). It insists that only in case of earthquakes the landslide in volcanic sediment apt to occur at the mild gradient slopes as well as on the ridges with convex cross section. Consequently, the following results are obtained. 1) At volcanic

  15. Effect of medical institution change on gestational duration after the Great East Japan Earthquake: The Fukushima Health Management Survey.

    PubMed

    Suzuki, Kohta; Goto, Aya; Fujimori, Keiya

    2016-12-01

    The aim of this study was to examine the association between medical institution change for perinatal care and gestational duration after the Great East Japan Earthquake using data from the Fukushima Health Management Survey. The data of pregnant women who experienced the earthquake in Fukushima prefecture and participated in the Pregnancy and Birth Survey as part of the Fukushima Health Management Survey were analyzed. The primary and secondary outcomes of this study were gestational duration and preterm birth, respectively. The main study factor was prenatal checkup institution (only one institution, changed institution due to self-referral, changed institution due to medical indication, and went to parents' home for childbirth). Self-referral was considered as indicative of relocation after the disaster. Multiple linear and logistic regression analyses were conducted to examine the effect of earthquake on each outcome. A total of 5593 (60.2%) participants experienced the earthquake between the 4th and 37th weeks of their gestational period. After controlling for variables, pregnant women who changed their perinatal checkup institution due to medical indication were significantly associated with shorter gestational duration (β = -10.6, P < 0.001) and preterm birth (adjusted odds ratio, 8.5; 95% confidence interval, 5.8-12.5) compared with women who visited only one institution. Self-referral, however, was not significantly associated with the outcomes. According to prenatal checkup status, our results suggest that the effect on gestational duration of the Great East Japan Earthquake and the subsequent Fukushima Daiichi nuclear disaster was not significant. © 2016 Japan Society of Obstetrics and Gynecology.

  16. Pain, quality of life and activity in aged evacuees living in temporary housing after the Great East Japan earthquake of 11 March 2011: a cross-sectional study in Minamisoma City, Fukushima prefecture.

    PubMed

    Yabuki, Shoji; Ouchi, Kazuo; Kikuchi, Shin-ichi; Konno, Shin-ichi

    2015-09-10

    The aim of this study was to clarify pain, quality of life and activity in the aged evacuees living in temporary housing after the Great East Japan Earthquake on 11 March 2011. The study was a cross-sectional study performed in Minamisoma City, Fukushima Prefecture 1 year and 6 months after the disaster. Inclusion criteria were the ability to walk independently and consent to answer questionnaires. Seventy-one evacuees who met the inclusion criteria were included in this study. There were 16 men and 55 women with a mean age of 75.9 years. Sixty evacuees were surveyed when they gathered at the assembly hall in the temporary housing (Assembled group) and 11 evacuees were surveyed through individual visits to their residences (Individual group). Evacuees in the Individual group agreed to participate in this study, but refused to visit the assembly hall to engage in exercise and recreation. Pain, quality of life (QOL) and level of activity were assessed with the Numeric Rating Scale (NRS), the MOS Short-Form 36 item Health Survey (SF-36) and a pedometer, respectively. Student's t-test, Mann-Whitney U test, and Fisher's exact test were used for statistical analysis. Forty-four (62.0 %) residents had chronic pain with a mean NRS of 2.74. Twenty-one (29.6 %) of these residents had relatively severe pain rated 5 or above on the NRS. QOL was significantly lower for the subscales of "physical functioning," "role physical", "general health", "social functioning", "role emotional" and "mental health", when compared with the national standard values. Values were also visibly lower for "physical component summary" in the summary score. On comparing the Assembled group and the Individual group, "physical function", "role physical", "social functioning" and "physical component summary" were found to be significantly lower in the Individual group. The mean daily number of steps was 1,892 in the Individual group and 4,579 in the Assembled group. The Individual group thus

  17. The HayWired Earthquake Scenario—Earthquake Hazards

    USGS Publications Warehouse

    Detweiler, Shane T.; Wein, Anne M.

    2017-04-24

    The HayWired scenario is a hypothetical earthquake sequence that is being used to better understand hazards for the San Francisco Bay region during and after an earthquake of magnitude 7 on the Hayward Fault. The 2014 Working Group on California Earthquake Probabilities calculated that there is a 33-percent likelihood of a large (magnitude 6.7 or greater) earthquake occurring on the Hayward Fault within three decades. A large Hayward Fault earthquake will produce strong ground shaking, permanent displacement of the Earth’s surface, landslides, liquefaction (soils becoming liquid-like during shaking), and subsequent fault slip, known as afterslip, and earthquakes, known as aftershocks. The most recent large earthquake on the Hayward Fault occurred on October 21, 1868, and it ruptured the southern part of the fault. The 1868 magnitude-6.8 earthquake occurred when the San Francisco Bay region had far fewer people, buildings, and infrastructure (roads, communication lines, and utilities) than it does today, yet the strong ground shaking from the earthquake still caused significant building damage and loss of life. The next large Hayward Fault earthquake is anticipated to affect thousands of structures and disrupt the lives of millions of people. Earthquake risk in the San Francisco Bay region has been greatly reduced as a result of previous concerted efforts; for example, tens of billions of dollars of investment in strengthening infrastructure was motivated in large part by the 1989 magnitude 6.9 Loma Prieta earthquake. To build on efforts to reduce earthquake risk in the San Francisco Bay region, the HayWired earthquake scenario comprehensively examines the earthquake hazards to help provide the crucial scientific information that the San Francisco Bay region can use to prepare for the next large earthquake, The HayWired Earthquake Scenario—Earthquake Hazards volume describes the strong ground shaking modeled in the scenario and the hazardous movements of

  18. Follow-up study of the regional quota system of Japanese medical schools and prefecture scholarship programmes: a study protocol.

    PubMed

    Matsumoto, Masatoshi; Takeuchi, Keisuke; Tanaka, Junko; Tazuma, Susumu; Inoue, Kazuo; Owaki, Tetsuhiro; Iguchi, Seitaro; Maeda, Takahiro

    2016-04-15

    Given the shortage of physicians, particularly in rural areas, the Japanese government has rapidly expanded the number of medical school students by adding chiikiwaku (regional quotas) since 2008. Quota entrants now account for 17% of all medical school entrants. Quota entrants are usually local high school graduates who receive a scholarship from the prefecture government. In exchange, they temporarily practise in that prefecture, including its rural areas, after graduation. Many prefectures also have scholarship programmes for non-quota students in exchange for postgraduate in-prefecture practice. The objective of this cohort study, conducted by the Japanese Council for Community-based Medical Education, is to evaluate the outcomes of the quota admission system and prefecture scholarship programmes nationwide. There are 3 groups of study participants: quota without scholarship, quota with scholarship and non-quota with scholarship. Under the support of government ministries and the Association of Japan Medical Colleges, and participation of all prefectures and medical schools, passing rate of the National Physician License Examination, scholarship buy-out rate, geographic distribution and specialties distribution of each group are analysed. Participants who voluntarily participated are followed by linking their baseline information to data in the government's biennial Physician Census. Results to date have shown that, despite medical schools' concerns about academic quality, the passing rate of the National Physician License Examination in each group was higher than that of all medical school graduates. The Ethics Committee for Epidemiological Research of Hiroshima University and the Research Ethics Committee of Nagasaki University Graduate School of Biomedical Sciences permitted this study. No individually identifiable results will be presented in conferences or published in journals. The aggregated results will be reported to concerned government ministries

  19. Earthquakes

    MedlinePlus

    ... Search Term(s): Main Content Home Be Informed Earthquakes Earthquakes An earthquake is the sudden, rapid shaking of the earth, ... by the breaking and shifting of underground rock. Earthquakes can cause buildings to collapse and cause heavy ...

  20. Characteristics of pneumonia deaths after an earthquake and tsunami: an ecological study of 5.7 million participants in 131 municipalities, Japan

    PubMed Central

    Shibata, Yosuke; Ojima, Toshiyuki; Tomata, Yasutake; Okada, Eisaku; Nakamura, Mieko; Kawado, Miyuki; Hashimoto, Shuji

    2016-01-01

    Objective On 11 March 2011, the Great East Japan Earthquake struck off Japan. Although some studies showed that the earthquake increased the risk of pneumonia death, no study reported whether and how much a tsunami increased the risk. We examined the risk for pneumonia death after the earthquake/tsunami. Design This is an ecological study. Setting Data on population and pneumonia deaths obtained from the Vital Statistics 2010 and 2012, National Census 2010 and Basic Resident Register 2010 and 2012 in Japan. Participants About 5.7 million participants residing in Miyagi, Iwate and Fukushima Prefectures during 1 year after the disaster were targeted. All municipalities (n=131) were categorised into inland (n=93), that is, the earthquake-impacted area, and coastal types (n=38), that is, the earthquake-impacted and tsunami-impacted area. Outcome measures The number of pneumonia deaths per week was totalled from 12 March 2010 to 9 March 2012. The number of observed pneumonia deaths (O) and the sum of the sex and age classes in the observed population multiplied by the sex and age classes of expected pneumonia mortality (E) were calculated. Expected pneumonia mortality was the pneumonia mortality during the year before. Standardised mortality ratios (SMRs) were calculated for pneumonia deaths (O/E), adjusting for sex and age using the indirect method. SMRs were then calculated by coastal and inland municipalities. Results 6603 participants died of pneumonia during 1 year after the earthquake. SMRs increased significantly during the 1st–12th weeks. In the 2nd week, SMRs in coastal and inland municipalities were 2.49 (95% CI 2.02 to 7.64) and 1.48 (95% CI 1.24 to 2.61), respectively. SMRs of coastal municipalities were higher than those of inland municipalities. Conclusions An earthquake increased the risk of pneumonia death and tsunamis additionally increased the risk. PMID:26908515

  1. Population-based sexual behavior surveys in China: Liuzhou compared with other prefectural cities.

    PubMed

    Huang, Yingying; Abler, Laurie; Pan, Suiming; Henderson, Gail E; Wang, Xin; Yao, Xingliang; Parish, William L

    2014-02-01

    Sexual behaviors in China are rapidly changing; simultaneously, sexually transmitted infections (STI)/HIV prevalence is increasing in the general population. To investigate these major shifts, we examined sexual behaviors and self-reported STI in one prefectural city in southern China, Liuzhou, and compared it to other prefectural cities throughout China. We used adults age 18-39 from two sets of population-based surveys that paralleled each other in both content and method. The first set was the Liuzhou survey conducted in 2008 (n = 398). The second set consisted of two national surveys collected in 2006 and 2010 (n = 2,186). Liuzhou respondents reported more active social and sexual behaviors than their national counterparts, including more socializing, dancing, drinking excessively, sexual activity among never married men and women, purchasing commercial sex among men, one-night stands among men, multiple sexual partnerships and self-reported STI among both men and women. Women in Liuzhou reported greater sexual risk behavior than their national counterparts, although overall they reported less than their male counterparts; they were also more likely to have had an abortion than women in other prefectural cities. Our findings provide a comprehensive overview of the sexual context of Liuzhou among the general population, which may help explain the greater STI/HIV prevalence in Liuzhou.

  2. Population-based sexual behavior surveys in China: Liuzhou compared with other prefectural cities

    PubMed Central

    Yingying, Huang; Abler, Laurie; Suiming, Pan; Henderson, Gail E.; Xin, Wang; Xingliang, Yao; Parish, William L.

    2013-01-01

    Sexual behaviors in China are rapidly changing; simultaneously, STI/HIV prevalence is increasing in the general population. To investigate these major shifts, we examined sexual behaviors and self-reported sexually transmitted infections (STI) in one prefectural city in southern China, Liuzhou, and compared it to other prefectural cities throughout China. We used adults age 18-39 from two sets of population-based surveys that paralleled each other in both content and method. The first set was the Liuzhou survey conducted in 2008 (n=398). The second set consisted of two national surveys collected in 2006 and 2010 (n=2186). Liuzhou respondents reported more active social and sexual behaviors than their national counterparts, including more socializing, dancing, drinking excessively, sexual activity among never married men and women, purchasing commercial sex among men, one-night stands among men, multiple sexual partnerships and self-reported STI among both men and women. Women in Liuzhou reported greater sexual risk behavior than their national counterparts, although overall they reported less than their male counterparts; they were also more likely to have had an abortion than women in other prefectural cities. Our findings provide a comprehensive overview of the sexual context of Liuzhou among the general population, which may help explain the greater STI/HIV prevalence in Liuzhou. PMID:24174289

  3. Preseismic Changes of the Level and Temperature of Confined Groundwater related to the 2011 Tohoku Earthquake

    PubMed Central

    Orihara, Yoshiaki; Kamogawa, Masashi; Nagao, Toshiyasu

    2014-01-01

    Anomalous groundwater changes started three months before the 2011 M9.0 Off the Pacific coast of the Tohoku Earthquake (Tohoku EQ), Japan. Groundwater level and temperature decreased almost simultaneously in a 2000-m well at a spa, Goyo-onsen, in Iwate Prefecture, 155 km northwest of the epicenter. Since the source of Goyo-onsen, located above the edge of a coseismic rupture area of the Tohoku EQ fault, is probably confined, the observed anomalies were caused probably by preseismic crustal deformation. Preseismic groundwater anomalies have been observed prior to similar large subduction EQs such as the 1946 M8.1 Nankai EQ. Thus, monitoring confined groundwater may be useful to identify precursors of large subduction EQs. PMID:25366123

  4. Earthquakes.

    ERIC Educational Resources Information Center

    Walter, Edward J.

    1977-01-01

    Presents an analysis of the causes of earthquakes. Topics discussed include (1) geological and seismological factors that determine the effect of a particular earthquake on a given structure; (2) description of some large earthquakes such as the San Francisco quake; and (3) prediction of earthquakes. (HM)

  5. Epidemiology of Echinococcosis Among Schoolchildren in Golog Tibetan Autonomous Prefecture, Qinghai, China.

    PubMed

    Cai, Huixia; Guan, Yayi; Ma, Xiao; Wang, Liying; Wang, Hu; Su, Guoming; Zhang, Xuefei; Han, Xiumin; Ma, Junying; Liu, Yu Fang; Li, Jun; Zhang, Jingxiao; Wang, Yongshun; Wang, Wei; Du, Rui; Lei, Wen; Wu, Weiping

    2017-03-01

    Echinococcosis is a serious zoonotic parasitic disease that is highly endemic in Qinghai Province. The present study aimed to investigate the prevalence of echinococcosis among schoolchildren in Golog Tibetan Autonomous Prefecture to improve early diagnosis and treatment of patients and to provide information for echinococcosis prevention and control. A total of 11,260 schoolchildren from five counties (Maqin, Gander, Dari, Jiuzhi, and Banma) in Golog Tibetan Autonomous Prefecture, Qinghai Province, were screened for echinococcosis. Screening involved ultrasound imaging combined with serologic examination as an auxiliary diagnostic test. The prevalence of echinococcosis in the schoolchildren was 2.1% (235/11,260), with a rate of 0.8% for cystic echinococcosis (CE; 89/11,260) and 1.3% for alveolar echinococcosis (AE; 146/11,260). Additionally, one child had a mixed infection. The prevalence ranged between 1.1% and 4.1% among the five investigated counties, and was highest in Dari County (4.1%). The prevalence of echinococcosis was higher in girls than in boys and gradually increased with age. In addition, children with CE mainly had type 1 (CE1) and type 3 (CE3) lesions, and children with AE mainly had small-diameter calcified lesions, suggesting that they were in the early asymptomatic stage of echinococcosis. In conclusion, children of Golog Tibetan Autonomous Prefecture appear to exhibit the highest recorded prevalence of CE and AE globally. Ultrasound is useful for screening populations in regions where both CE and AE are endemic.

  6. Epidemiology of Echinococcosis among Schoolchildren in Golog Tibetan Autonomous Prefecture, Qinghai, China

    PubMed Central

    Cai, Huixia; Guan, Yayi; Ma, Xiao; Wang, Liying; Wang, Hu; Su, Guoming; Zhang, Xuefei; Han, Xiumin; Ma, Junying; Liu, Yu Fang; Li, Jun; Zhang, Jingxiao; Wang, Yongshun; Wang, Wei; Du, Rui; Lei, Wen; Wu, Weiping

    2017-01-01

    Echinococcosis is a serious zoonotic parasitic disease that is highly endemic in Qinghai Province. The present study aimed to investigate the prevalence of echinococcosis among schoolchildren in Golog Tibetan Autonomous Prefecture to improve early diagnosis and treatment of patients and to provide information for echinococcosis prevention and control. A total of 11,260 schoolchildren from five counties (Maqin, Gander, Dari, Jiuzhi, and Banma) in Golog Tibetan Autonomous Prefecture, Qinghai Province, were screened for echinococcosis. Screening involved ultrasound imaging combined with serologic examination as an auxiliary diagnostic test. The prevalence of echinococcosis in the schoolchildren was 2.1% (235/11,260), with a rate of 0.8% for cystic echinococcosis (CE; 89/11,260) and 1.3% for alveolar echinococcosis (AE; 146/11,260). Additionally, one child had a mixed infection. The prevalence ranged between 1.1% and 4.1% among the five investigated counties, and was highest in Dari County (4.1%). The prevalence of echinococcosis was higher in girls than in boys and gradually increased with age. In addition, children with CE mainly had type 1 (CE1) and type 3 (CE3) lesions, and children with AE mainly had small-diameter calcified lesions, suggesting that they were in the early asymptomatic stage of echinococcosis. In conclusion, children of Golog Tibetan Autonomous Prefecture appear to exhibit the highest recorded prevalence of CE and AE globally. Ultrasound is useful for screening populations in regions where both CE and AE are endemic. PMID:28070013

  7. Earthquakes.

    ERIC Educational Resources Information Center

    Pakiser, Louis C.

    One of a series of general interest publications on science topics, the booklet provides those interested in earthquakes with an introduction to the subject. Following a section presenting an historical look at the world's major earthquakes, the booklet discusses earthquake-prone geographic areas, the nature and workings of earthquakes, earthquake…

  8. Immediate effects of the Fukushima nuclear power plant disaster on depressive symptoms among mothers with infants: a prefectural-wide cross-sectional study from the Fukushima Health Management Survey.

    PubMed

    Goto, Aya; Bromet, Evelyn J; Fujimori, Kenya

    2015-03-26

    Mothers of young children are at high-risk for developing adverse mental health effects following a nuclear accident. Using the Japanese pregnancy registration system, the prefecture of Fukushima launched a population-based survey of women who were pregnant at the time of the Fukushima nuclear accident in order to assess their and their newborns' health. In this paper, we focus on the results of a screen for depressive symptoms among new mothers and its association with geographical region and interruption of obstetrical care after the Fukushima nuclear accident, which occurred after the Great East Japan Earthquake on March 11, 2011. The survey targeted women who lived in Fukushima prefecture and who had registered their pregnancies between August 1, 2010 and July 31, 2011. Among the 16,001 women targeted, 9,321 returned the questionnaires (response proportion = 58.3%) and data from 8,196 women with singleton live births were analyzed. The main outcome measure was a standard two-item depression screen. Regional radiation levels were determined from the prefecture's periodical reports, and interruption in obstetrical care after the Fukushima nuclear accident was determined from mothers' individual responses to the questionnaire. Among the 8,196 women, 2,262 (28%) screened positive for depressive symptoms. After adjusting for maternal and infant characteristics, both mothers in Soso, the region in which the nuclear power plant is located, and mothers that had changed obstetrical care facilities were significantly more likely to screen positive for depression. In contrast, mothers in Iwaki and Aizu, regions with relatively low radiation levels, were significantly less likely to screen positive for depression. Our findings suggest that improving mental health support for mothers with infants should be a high priority in the acute phase of nuclear disaster response. We further recommend that in the strategic provisioning of parental support, close attention should

  9. Use of the Physiotherapy Evidence Database (PEDro) in Japan

    PubMed Central

    TAKASAKI, Hiroshi; ELKINS, Mark R.; MOSELEY, Anne M.

    2016-01-01

    Background: The Physiotherapy Evidence Database (PEDro) may help users to overcome some obstacles to evidence-based physiotherapy. Understanding the extent to which Japanese physiotherapists access research evidence via the PEDro website may suggest strategies to enhance evidence-based physiotherapy in Japan. Objectives: To quantify usage of PEDro in Japan, to compare this to usage in other countries, and to examine variations in PEDro usage within Japan. Design: An observational study of PEDro usage with geographic analysis. Methods: Data about visits to the home-page and searches of the database were recorded for 4 years. These data were analysed by each region of the World Confederation for Physical Therapy, each country in the Asia Western Pacific region, and each prefecture in Japan. Results: From 2010 to 2013, users of PEDro made 2.27 million visits to the home-page and ran 6.28 million searches. Usage (ie, number of searches normalised by population) was highest in Europe, followed by North America Carribean, South America, Asia Western Pacific, and Africa. Within the Asia Western Pacific region, population-normalised usage was highest in Australia, then New Zealand and Singapore. Japan ranked 10 among the 26 countries in the region. Within Japan, the highest population-normalised usage was in the Nagano, Kumamoto and Aomori prefectures, which was ten-fold higher usage than in some other prefectures. Conclusions: Although Japan has higher PEDro usage than many other countries in the Asia Western Pacific region, some prefectures had very low usage, suggesting that evidence-based practice may not be being adopted uniformly across Japan. PMID:28289582

  10. High-Speed Observations of Dynamic Fracture Propagation in Solids and Their Implications in Earthquake Rupture Dynamics

    NASA Astrophysics Data System (ADS)

    Uenishi, Koji

    2016-04-01

    This contribution outlines our experimental observations of seismicity-related fast fracture (rupture) propagation in solids utilising high-speed analog and digital photography (maximum frame rate 1,000,000 frames per second) over the last two decades. Dynamic fracture may be triggered or initiated in the monolithic or layered seismic models by detonation of micro explosives, a projectile launched by a gun, laser pulses and electric discharge impulses, etc. First, we have investigated strike-slip rupture along planes of weakness in transparent photoelastic (birefringent) materials at a laboratory scale and shown (at that time) extraordinarily fast rupture propagation in a bi-material system and its possible effect on the generation of large strong motion in the limited narrow areas in the Kobe region on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake (Uenishi Ph.D. thesis 1997, Uenishi et al. BSSA 1999). In this series of experiments, we have also modelled shallow dip-slip earthquakes and indicated a possible origin of the asymmetric ground motion in the hanging and foot-walls. In the photoelastic photographs, we have found the unique dynamic wave interaction and generation of specific shear and interface waves numerically predicted by Uenishi and Madariaga (Eos 2005), and considered as a case study the seismic motion associated with the 2014 Nagano-ken Hokubu (Kamishiro Fault), Japan, dip-slip earthquake (Uenishi EFA 2015). Second, we have experimentally shown that even in a monolithic material, rupture speed may exceed the local shear wave speed if we employ hyperelasically behaving materials like natural rubber (balloons) (Uenishi Eos 2006, Uenishi ICF 2009, Uenishi Trans. JSME A 2012) but fracture in typical monolithic thin fluid films (e.g. soap bubbles, which may be treated as a solid material) propagates at an ordinary subsonic (sub-Rayleigh) speed (Uenishi et al. SSJ 2006). More recent investigation handling three-dimensional rupture propagation

  11. Aeromedical Transport Operations Using Helicopters during the 2016 Kumamoto Earthquake in Japan.

    PubMed

    Motomura, Tomokazu; Hirabayashi, Atsushi; Matsumoto, Hisashi; Yamauchi, Nobutaka; Nakamura, Mitsunobu; Machida, Hiroshi; Fujizuka, Kenji; Otsuka, Naomi; Satoh, Tomoko; Anan, Hideaki; Kondo, Hisayoshi; Koido, Yuichi

    2018-01-01

    More than 6,000 people died in the Great Hanshin (Kobe) Earthquake in 1995, and it was later reported that there were around 500 preventable trauma deaths. In response, the Japanese government developed the helicopter emergency medical service in 2001, known in Japan as the "Doctor-Heli" (DH), which had 46 DHs and 2 private medical helicopters as of April 2016. DHs transport physicians and nurses to provide pre-hospital medical care at the scene of medical emergencies. Following lessons learned in the Great East Japan Earthquake in 2011, a research group in the Ministry of Health, Labour and Welfare developed a command and control system for the DH fleet as well as the Disaster Relief Aircraft Management System Network (D-NET), which uses a satellite communications network to monitor the location of the fleet and weather in real-time during disasters. During the Kumamoto Earthquake disaster in April 2016, 75 patients were transported by 13 DHs and 1 private medical helicopter in the first 5 days. When medical demand for the DHs exceeded supply, 5 patients, 8 patients, and 1 patient were transported by Self-Defense Force, Fire Department, and Coast Guard helicopters, respectively. Of the 89 patients who were transported, 30 (34%) had trauma, 3 (3%) had pulmonary embolisms caused by sleeping in vehicles, and 17 (19%) were pregnant women or newborns. This was the first time that the command and control system for aeromedical transport and D-NET, established after the Great East Japan Earthquake in 2011, were operated in an actual large-scale disaster. Aeromedical transport by DHs and helicopters belonging to several other organizations was accomplished smoothly because the commanders of the involved organizations could communicate directly with each other in person within the Aviation Coordination Section of the prefectural government office. However, ongoing challenges in the detailed operating methods for aeromedical transport were highlighted and include improving

  12. Earthquake Early Warning in Japan - Result of recent two years -

    NASA Astrophysics Data System (ADS)

    Shimoyama, T.; Doi, K.; Kiyomoto, M.; Hoshiba, M.

    2009-12-01

    Japan Meteorological Agency(JMA) started to provide Earthquake Early Warning(EEW) to the general public in October 2007. It was followed by provision of EEW to a limited number of users who understand the technical limit of EEW and can utilize it for automatic control from August 2006. Earthquake Early Warning in Japan definitely means information of estimated amplitude and arrival time of a strong ground motion after fault rupture occurred. In other words, the EEW provided by JMA is defined as a forecast of a strong ground motion before the strong motion arrival. EEW of JMA is to enable advance countermeasures to disasters caused by strong ground motions with providing a warning message of anticipating strong ground motion before the S wave arrival. However, due to its very short available time period, there should need some measures and ideas to provide rapidly EEW and utilize it properly. - EEW is issued to general public when the maximum seismic intensity 5 lower (JMA scale) or greater is expected. - EEW message contains origin time, epicentral region name, and names of areas (unit is about 1/3 to 1/4 of one prefecture) where seismic intensity 4 or greater is expected. Expected arrival time is not included because it differs substantially even in one unit area. - EEW is to be broadcast through the broadcasting media(TV, radio and City Administrative Disaster Management Radio), and is delivered to cellular phones through cell broadcast system. For those who would like to know the more precise estimation and smaller earthquake information at their point of their properties, JMA allows designated private companies to provide forecast of strong ground motion, in which the estimation of a seismic intensity as well as arrival time of S-wave are contained, at arbitrary places under the JMA’s technical assurance. From October, 2007 to August, 2009, JMA issued 11 warnings to general public expecting seismic intensity “5 lower” or greater, including M=7.2 inland

  13. The Relationship between Attitudes toward Suicide and Family History of Suicide in Nagano Prefecture, Japan.

    PubMed

    Tsukahara, Teruomi; Arai, Hiroaki; Kamijo, Tomoko; Kobayashi, Yoshikiyo; Washizuka, Shinsuke; Arito, Heihachiro; Nomiyama, Tetsuo

    2016-06-22

    Certain attitudes toward suicide may be a risk factor for suicide among the bereaved. To explore this possibility, we examined the relationship between attitudes toward suicide and family history of suicide. We focused on two specific attitudes indicating resignation in a survey: #1 "When a person chooses to die by suicide, the suicide is inevitable" (i.e., inevitability belief); and #2 "A suicide cannot be stopped by any person, because suicide is unpreventable" (i.e., unpreventable belief). The data of 5117 fully completed questionnaires were analyzed. Logistic regression analysis revealed that the two attitudes of resignation were significantly associated with a family history of suicide. The adjusted odds ratio for #1 was 1.39 (95% CI, 1.07-1.79) for individuals having experienced suicide by a family member or relative, while that for #2 was 1.57 (95% CI, 1.27-1.95) for experiencing a suicide by a family member or relative and 1.25 (95% CI, 1.05-1.49) for experiencing a suicide by a friend, business associate, partner or other. These two attitudes of resignation toward suicide were significantly associated with a family history of suicide. These attitudes might increase suicide risk among the bereaved.

  14. Distribution of Rotavirus Genotypes from the 2008/2009 to the 2015/2016 Season in Nara Prefecture, Japan.

    PubMed

    Sugimoto, Daichi; Nakano, Mamoru; Inada, Machi; Fujitani, Misako; Chiba, Shoko; Sakai, Takeshi

    2017-09-25

    This study was conducted to investigate the distribution of rotavirus genotypes in Nara Prefecture, Japan before and after the introduction of rotavirus vaccination in 2011. Since the 2011/2012 season, DS-1-like G1P[8] strains have been detected in Nara Prefecture, accounting for about half of all strains in the 2014/2015 season. During the 2015/2016 season, no DS-1-like G1P[8] strains were detected; G2P[4] was the predominant genotype.

  15. [Food borne outbreak caused by the well water contaminated norovirus].

    PubMed

    Tokutake, Yumi; Kobayashi, Masato; Akiyama, Miho; Aiki, Chikako; Nishio, Osamu

    2006-05-01

    In May 2004, 65 people from 18 groups of visitors to guesthouse (a traditional Japanese guesthouse) in the Nagano Prefecture, Japan developed acute gastroenteritis. Although these cases originally attributed to food poisoning, based on epidemiological and dietary surveys, there was nothing that is associated as a cause food. The same wall water was used throughout the guesthouse except in the kitchen, so testing was conducted on this water. Lordsdale variant strain of Norovirus was detected from both of the well water and the feces of patients and staff. The well supplying to the guesthouse was only 10 meters deep and fecal coliform group was also detected in the well water from the guesthouse. This suggested that the water source was contaminated by human feces.

  16. Transplant Procurement Management Model Training: Marked Improvement in the Mindset of In-Hospital Procurement Coordinators at Hyogo Prefecture, Japan.

    PubMed

    Yoshikawa, M; Yoshinaga, K; Imamura, Y; Hayashi, T; Osako, T; Takahashi, K; Kaneko, M; Fujisawa, M; Kamidono, S

    2016-09-01

    The organ donation rate in Japan is much lower than that in other developed countries for several reasons. An advanced educational program for in-hospital procurement coordinators is a possible solution for this. We introduced a Transplant Procurement Management (TPM) educational program at Hyogo Prefecture, Japan. Ten healthcare professionals at Hyogo Prefecture participated in the Advanced International TPM course to educate themselves on TPM and held 2 TPM Model Organ Procurement Training Workshops at Hyogo Prefecture for in-hospital procurement coordinators. Furthermore, we held 2 workshops outside Hyogo Prefecture and at the same time undertook a pre-workshop questionnaire survey to evaluate the ability and motivation with respect to organ donation. To evaluate the effectiveness of the workshops, we conducted post-workshop and 3-months-after workshop questionnaire surveys. The results of the pre-workshop survey revealed that in-hospital procurement coordinators lacked the knowledge regarding the entire organ donation process, the current status of organ donation in Japan, and the definition of brain death. Moreover, they did not completely understand the meaning of "organ donation." The results of the post-workshop questionnaire survey showed that the educational program was effective to improve the knowledge and skills of organ donation and motivated behavioral changes among the participants. The survey results showed that our TPM model educational program offered sufficient knowledge and skills to increase organ donation at Hyogo Prefecture. We will continue this program and make an effort to further contribute to the Japanese organ donation activities. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. The 2004 Parkfield, CA Earthquake: A Teachable Moment for Exploring Earthquake Processes, Probability, and Earthquake Prediction

    NASA Astrophysics Data System (ADS)

    Kafka, A.; Barnett, M.; Ebel, J.; Bellegarde, H.; Campbell, L.

    2004-12-01

    The occurrence of the 2004 Parkfield earthquake provided a unique "teachable moment" for students in our science course for teacher education majors. The course uses seismology as a medium for teaching a wide variety of science topics appropriate for future teachers. The 2004 Parkfield earthquake occurred just 15 minutes after our students completed a lab on earthquake processes and earthquake prediction. That lab included a discussion of the Parkfield Earthquake Prediction Experiment as a motivation for the exercises they were working on that day. Furthermore, this earthquake was recorded on an AS1 seismograph right in their lab, just minutes after the students left. About an hour after we recorded the earthquake, the students were able to see their own seismogram of the event in the lecture part of the course, which provided an excellent teachable moment for a lecture/discussion on how the occurrence of the 2004 Parkfield earthquake might affect seismologists' ideas about earthquake prediction. The specific lab exercise that the students were working on just before we recorded this earthquake was a "sliding block" experiment that simulates earthquakes in the classroom. The experimental apparatus includes a flat board on top of which are blocks of wood attached to a bungee cord and a string wrapped around a hand crank. Plate motion is modeled by slowly turning the crank, and earthquakes are modeled as events in which the block slips ("blockquakes"). We scaled the earthquake data and the blockquake data (using how much the string moved as a proxy for time) so that we could compare blockquakes and earthquakes. This provided an opportunity to use interevent-time histograms to teach about earthquake processes, probability, and earthquake prediction, and to compare earthquake sequences with blockquake sequences. We were able to show the students, using data obtained directly from their own lab, how global earthquake data fit a Poisson exponential distribution better

  18. Sleep duration among children 8 months after the 2011 Japan earthquake and tsunami.

    PubMed

    Usami, Masahide; Iwadare, Yoshitaka; Kodaira, Masaki; Watanabe, Kyota; Aoki, Momoko; Katsumi, Chiaki; Matsuda, Kumi; Makino, Kazunori; Iijima, Sonoko; Harada, Maiko; Tanaka, Hiromi; Sasaki, Yoshinori; Tanaka, Tetsuya; Ushijima, Hirokage; Saito, Kazuhiko

    2013-01-01

    To elucidate relationships between disaster damage conditions and sleep duration among children who survived the 2011 Japan earthquake and tsunami. The subjects comprised 12,524 children in kindergartens, elementary schools, and junior high schools in Ishinomaki City, Miyagi Prefecture, Japan. The Post Traumatic Stress Symptoms for Children 15 items (PTSSC-15), a self-completion questionnaire on traumatic symptoms, and a sleep questionnaire were distributed to them. A questionnaire regarding disaster damage conditions of the children's homes was distributed to their teachers. Of 12,524, an effective response was obtained from 11,692 (93.3%). Relationships between sleep duration and traumatic symptoms were displayed low correlations. Children with house damage and/or evacuation experiences slept for a significantly shorter time than children without these experiences. It is critical not only to examine traumatic symptoms in children but also to collect sleep duration and disaster damage conditions following natural disasters.

  19. Earthquakes

    MedlinePlus

    An earthquake happens when two blocks of the earth suddenly slip past one another. Earthquakes strike suddenly, violently, and without warning at any time of the day or night. If an earthquake occurs in a populated area, it may cause ...

  20. Investigation of the M6.6 Niigata-Chuetsu Oki, Japan, earthquake of July 16, 2007

    USGS Publications Warehouse

    Kayen, Robert; Collins, Brian D.; Abrahamson, Norm; Ashford, Scott; Brandenberg, Scott J.; Cluff, Lloyd; Dickenson, Stephen; Johnson, Laurie; Tanaka, Yasuo; Tokimatsu, Kohji; Kabeyasawa, Toshimi; Kawamata, Yohsuke; Koumoto, Hidetaka; Marubashi, Nanako; Pujol, Santiago; Steele, Clint; Sun, Joseph I.; Tsai, Ben; Yanev, Peter; Yashinsky, Mark; Yousok, Kim

    2007-01-01

    The M6.6 mainshock of the Niigata Chuetsu Oki (offshore) earthquake occurred at 10:13 a.m. local time on July 16, 2007, and was followed by a sequence of aftershocks that were felt during the entire time of the reconnaissance effort. The mainshock had an estimated focal depth of 10 km and struck in the Japan Sea offshore Kariwa. Analysis of waveforms from source inversion studies indicates that the event occurred along a thrust fault with a NE trend. The fault plane is either a strike of 34 degrees with a dip of 51 degrees or a strike of 238 degrees with a dip of 41 degrees. Which of these two planes is associated with the mainshock rupture is unresolved, although attenuation relationship analysis indicates that the northwest-dipping fault is favored. The quake affected an approximately 100-km-wide area along the coastal areas of southwestern Niigata prefecture. The event triggered ground failures as far as the Unouma Hills, located in central Niigata approximately 50 km from the shore and the source area of the 2004 Niigata Chuetsu earthquake. The primary event produced tsunami run-ups that reached maximum runup heights of about 20 centimeters along the shoreline of southern Niigata Prrefecture.

  1. High Dropout Rate among Elementary and Middle School Students in Changed Prefecture.

    ERIC Educational Resources Information Center

    Yan, Weizhi; Chen, Benxiang

    1989-01-01

    Examines the high dropout rate among elementary and middle school students in Changed Prefecture. Lists and discusses four factors that contribute to this situation. Describes student attitudes toward school: studying is useless, excessive amounts of school work are given, misunderstandings concerning job placement exist, and tuition is high. (KO)

  2. Post-tsunami outbreaks of influenza in evacuation centers in Miyagi Prefecture, Japan.

    PubMed

    Hatta, Masumitsu; Endo, Shiro; Tokuda, Koichi; Kunishima, Hiroyuki; Arai, Kazuaki; Yano, Hisakazu; Ishibashi, Noriomi; Aoyagi, Tetsuji; Yamada, Mitsuhiro; Inomata, Shinya; Kanamori, Hajime; Gu, Yoshiaki; Kitagawa, Miho; Hirakata, Yoichi; Kaku, Mitsuo

    2012-01-01

    We describe 2 post-tsunami outbreaks of influenza A in evacuation centers in Miyagi Prefecture, Japan, in 2011. Although containment of the outbreak was challenging in the evacuation settings, prompt implementation of a systemic approach with a bundle of control measures was important to control the influenza outbreaks.

  3. Impact of the Japan earthquake disaster with massive Tsunami on emergency coronary intervention and in-hospital mortality in patients with acute ST-elevation myocardial infarction.

    PubMed

    Itoh, Tomonori; Nakajima, Satoshi; Tanaka, Fumitaka; Nishiyama, Osamu; Matsumoto, Tatsuya; Endo, Hiroshi; Sakai, Toshiaki; Nakamura, Motoyuki; Morino, Yoshihiro

    2014-09-01

    The aims of this study were to evaluate reperfusion rate, therapeutic time course and in-hospital mortality pre- and post-Japan earthquake disaster, comparing patients with ST-elevation myocardial infarction (STEMI) treated in the inland area or the Tsunami-stricken area of Iwate prefecture. Subjects were 386 consecutive STEMI patients admitted to the four percutaneous coronary intervention (PCI) centers in Iwate prefecture in 2010 and 2011. Patients were divided into two groups: those treated in the inland or Tsunami-stricken area. We compared clinical characteristics, time course and in-hospital mortality in both years in the two groups. PCI was performed in 310 patients (80.3%). Door-to-balloon (D2B) time in the Tsunami-stricken area in 2011 was significantly shorter than in 2010 in patients treated with PCI. However, the rate of PCI performed in the Tsunami-stricken area in March-April 2011 was significantly lower than that in March-April 2010 (41.2% vs 85.7%; p=0.03). In-hospital mortality increased three-fold from 7.1% in March-April 2010 to 23.5% in March-April 2011 in the Tsunami-stricken area. Standardized mortality ratio (SMR) in March-April 2011 in the Tsunami-stricken area was significantly higher than the control SMR (SMR 4.72: 95% confidence interval (CI): 1.77-12.6: p=0.007). The rate of PCI decreased and in-hospital mortality increased immediately after the Japan earthquake disaster in the Tsunami-stricken area. Disorder in hospitals and in the distribution systems after the disaster impacted the clinical care and outcome of STEMI patients. © The European Society of Cardiology 2014.

  4. Characteristics of pneumonia deaths after an earthquake and tsunami: an ecological study of 5.7 million participants in 131 municipalities, Japan.

    PubMed

    Shibata, Yosuke; Ojima, Toshiyuki; Tomata, Yasutake; Okada, Eisaku; Nakamura, Mieko; Kawado, Miyuki; Hashimoto, Shuji

    2016-02-23

    On 11 March 2011, the Great East Japan Earthquake struck off Japan. Although some studies showed that the earthquake increased the risk of pneumonia death, no study reported whether and how much a tsunami increased the risk. We examined the risk for pneumonia death after the earthquake/tsunami. This is an ecological study. Data on population and pneumonia deaths obtained from the Vital Statistics 2010 and 2012, National Census 2010 and Basic Resident Register 2010 and 2012 in Japan. About 5.7 million participants residing in Miyagi, Iwate and Fukushima Prefectures during 1 year after the disaster were targeted. All municipalities (n=131) were categorised into inland (n=93), that is, the earthquake-impacted area, and coastal types (n=38), that is, the earthquake-impacted and tsunami-impacted area. The number of pneumonia deaths per week was totalled from 12 March 2010 to 9 March 2012. The number of observed pneumonia deaths (O) and the sum of the sex and age classes in the observed population multiplied by the sex and age classes of expected pneumonia mortality (E) were calculated. Expected pneumonia mortality was the pneumonia mortality during the year before. Standardised mortality ratios (SMRs) were calculated for pneumonia deaths (O/E), adjusting for sex and age using the indirect method. SMRs were then calculated by coastal and inland municipalities. 6603 participants died of pneumonia during 1 year after the earthquake. SMRs increased significantly during the 1st-12th weeks. In the 2nd week, SMRs in coastal and inland municipalities were 2.49 (95% CI 2.02 to 7.64) and 1.48 (95% CI 1.24 to 2.61), respectively. SMRs of coastal municipalities were higher than those of inland municipalities. An earthquake increased the risk of pneumonia death and tsunamis additionally increased the risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  5. Repeat microearthquakes observed in western Nagano, Japan and implications to rupture dynamics

    NASA Astrophysics Data System (ADS)

    Cheng, X.; Niu, F.; Silver, P.; Horiuchi, S.; Takai, K.

    2005-12-01

    Repeat earthquakes appear to be pervasive in many fault systems, and have been used to detect temporal variations, either coseismic or post seismic near fault zones as well as to understand dynamic rupture processes. For example, Rubin and Gillard (2000) found no evidence of "immediate repeaters" in the San Juan Bautista section of the San Andreas Fault. Consecutive repeat earthquakes occurred no closer than a distance equal to the radius of the first rupture, which is estimated by a stress drop of 10 MPa. Here we reported similar characteristics of repeat microearthquakes from a very different environment, a complicated intraplate fault system in Western Nagao, Central Japan. A magnitude 6.8 shallow earthquake (roughly right lateral strike slip) occurred in the study area in 1984. Very high level of seismicity continues since then. A very dense seismic network with 56 stations including two borehole seismometers has been set up to monitor the high level seismic activity in 1995. Continuous data have been recorded at a very high sampling rate 10 KHz. We have searched repeat events from a catalog of more than 20,000 microearthquakes with a magnitude between 0 and 4.5. We calculated the cross-correlation of all the possible pairs of events and found less than 1% of the events can be categorized as repeat events, which is extremely lower compared to those observed at San Andreas Fault. More than 80% of the repeaters are actually aftershocks with the second events occurred within one day after the first ones. To avoid the tradeoff between origin time and event depth, we use relative S-P travel times to determine the relative locations of these consecutive repeat events. Based on the signal-to-noise ratio, we were able to estimate S-P time to an accuracy of 0.01 - 0.1 ms (1/10 to 1 sample interval). The corresponding errors in relative location are estimated to be a few tenths to a few meters. We also found that the second events occurred at least one radius away from

  6. The 1868 Hayward Earthquake Alliance: A Case Study - Using an Earthquake Anniversary to Promote Earthquake Preparedness

    NASA Astrophysics Data System (ADS)

    Brocher, T. M.; Garcia, S.; Aagaard, B. T.; Boatwright, J. J.; Dawson, T.; Hellweg, M.; Knudsen, K. L.; Perkins, J.; Schwartz, D. P.; Stoffer, P. W.; Zoback, M.

    2008-12-01

    Last October 21st marked the 140th anniversary of the M6.8 1868 Hayward Earthquake, the last damaging earthquake on the southern Hayward Fault. This anniversary was used to help publicize the seismic hazards associated with the fault because: (1) the past five such earthquakes on the Hayward Fault occurred about 140 years apart on average, and (2) the Hayward-Rodgers Creek Fault system is the most likely (with a 31 percent probability) fault in the Bay Area to produce a M6.7 or greater earthquake in the next 30 years. To promote earthquake awareness and preparedness, over 140 public and private agencies and companies and many individual joined the public-private nonprofit 1868 Hayward Earthquake Alliance (1868alliance.org). The Alliance sponsored many activities including a public commemoration at Mission San Jose in Fremont, which survived the 1868 earthquake. This event was followed by an earthquake drill at Bay Area schools involving more than 70,000 students. The anniversary prompted the Silver Sentinel, an earthquake response exercise based on the scenario of an earthquake on the Hayward Fault conducted by Bay Area County Offices of Emergency Services. 60 other public and private agencies also participated in this exercise. The California Seismic Safety Commission and KPIX (CBS affiliate) produced professional videos designed forschool classrooms promoting Drop, Cover, and Hold On. Starting in October 2007, the Alliance and the U.S. Geological Survey held a sequence of press conferences to announce the release of new research on the Hayward Fault as well as new loss estimates for a Hayward Fault earthquake. These included: (1) a ShakeMap for the 1868 Hayward earthquake, (2) a report by the U. S. Bureau of Labor Statistics forecasting the number of employees, employers, and wages predicted to be within areas most strongly shaken by a Hayward Fault earthquake, (3) new estimates of the losses associated with a Hayward Fault earthquake, (4) new ground motion

  7. A model-based estimation of inter-prefectural migration of physicians within Japan and associated factors: A 20-year retrospective study.

    PubMed

    Okada, Naoki; Tanimoto, Tetsuya; Morita, Tomohiro; Higuchi, Asaka; Yoshida, Izumi; Kosugi, Kazuhiro; Maeda, Yuto; Nishikawa, Yoshitaka; Ozaki, Akihiko; Tsuda, Kenji; Mori, Jinichi; Ohnishi, Mutsuko; Ward, Larry Wesley; Narimatsu, Hiroto; Yuji, Koichiro; Kami, Masahiro

    2018-06-01

    Despite an increase in the number of physicians in Japan, misdistribution of physicians within the 47 prefectures remains a major issue. Migration of physicians among prefectures might partly explain the misdistribution. However, geographical differences and the magnitude of physicians' migration are unclear. The aim of this study was to estimate the extent of migration of physicians among prefectures and explore possible factors associated with physicians' migration patterns.Using a publicly available government database from 1995 to 2014, a quantitative estimation of physicians' migration after graduation from a medical school was performed. The inflow and outflow of physicians were ostensibly calculated in each prefecture based on the differences between the number of newly licensed physicians and the actual number of practicing physicians after an adjustment for the number of deceased or retired physicians. Simple and multiple linear regression analyses were conducted to examine socio-demographic background factors.During the 20-year study period, the mean annual numbers of newly licensed physicians, deceased or retired physicians, and increase in practicing physicians in the whole country were 7416, 3382, and 4034, respectively. Among the 47 prefectures, the median annual number of newly licensed physicians to 100,000 population ratio (PPR) was 6.4 (range 1.5-16.5), the median annual adjusted number of newly licensed physicians was 61 (range, -18 to 845; the negative and positive values denote outflow and inflow, respectively), whereas the median annual number of migrating physicians was 13 (range, -171 to 241). The minimum and maximum migration ratios observed were -68% and 245%, respectively. In the final regression model of the 8 variables examined, only "newly licensed PPR" remained significantly associated with physician's migration ratios.A significant inequality in the proportion of the migration of physicians among prefectures in Japan was observed

  8. Evacuation of a Tertiary Neonatal Centre: Lessons from the 2016 Kumamoto Earthquakes

    PubMed Central

    Iwata, Osuke; Kawase, Akihiko; Iwai, Masanori; Wada, Kazuko

    2017-01-01

    Background Newborn infants hospitalised in the neonatal intensive care unit (NICU) are vulnerable to natural disasters. However, publications on evacuation from NICUs are sparse. The 2016 Kumamoto Earthquakes caused serious damage to Kumamoto City Hospital and its level III regional core NICU. Local/neighbour NICU teams and the disaster-communication team of a neonatal academic society cooperated to evacuate 38 newborn infants from the ward. Objective The aim of this paper was to highlight potential key factors to improve emergency NICU evacuation and coordination of hospital transportation following natural disasters. Methods Background variables including clinical risk scores and timing/destination of transportation were compared between infants, who subsequently were transferred to destinations outside of Kumamoto Prefecture, and their peers. Results All but 1 of the infants were successfully evacuated from their NICU within 8 h. One very-low-birth-weight infant developed moderate hypothermia following transportation. Fourteen infants were transferred to NICUs outside of Kumamoto Prefecture, which was associated with the diagnosis of congenital heart disease, dependence on respiratory support, higher risk scores, and longer elapsed time from the decision to departure. There was difficulty in arranging helicopter transportation because the coordination office of the Disaster Medical Assistance Team had requisitioned most air/ground ambulances and only helped arrange ground transportations for 13 low-risk infants. Transportation for all 10 high-risk infants (risk scores greater than or equal to the upper quartile) was arranged by local/neighbour NICUs. Conclusions Although the overall evacuation process was satisfactory, potential risks of relying on the adult-based emergency transportation system were highlighted. A better system needs to be developed urgently to put appropriate priority on vulnerable infants. PMID:28437783

  9. Evacuation of a Tertiary Neonatal Centre: Lessons from the 2016 Kumamoto Earthquakes.

    PubMed

    Iwata, Osuke; Kawase, Akihiko; Iwai, Masanori; Wada, Kazuko

    2017-01-01

    Newborn infants hospitalised in the neonatal intensive care unit (NICU) are vulnerable to natural disasters. However, publications on evacuation from NICUs are sparse. The 2016 Kumamoto Earthquakes caused serious damage to Kumamoto City Hospital and its level III regional core NICU. Local/neighbour NICU teams and the disaster-communication team of a neonatal academic society cooperated to evacuate 38 newborn infants from the ward. The aim of this paper was to highlight potential key factors to improve emergency NICU evacuation and coordination of hospital transportation following natural disasters. Background variables including clinical risk scores and timing/destination of transportation were compared between infants, who subsequently were transferred to destinations outside of Kumamoto Prefecture, and their peers. All but 1 of the infants were successfully evacuated from their NICU within 8 h. One very-low-birth-weight infant developed moderate hypothermia following transportation. Fourteen infants were transferred to NICUs outside of Kumamoto Prefecture, which was associated with the diagnosis of congenital heart disease, dependence on respiratory support, higher risk scores, and longer elapsed time from the decision to departure. There was difficulty in arranging helicopter transportation because the coordination office of the Disaster Medical Assistance Team had requisitioned most air/ground ambulances and only helped arrange ground transportations for 13 low-risk infants. Transportation for all 10 high-risk infants (risk scores greater than or equal to the upper quartile) was arranged by local/neighbour NICUs. Although the overall evacuation process was satisfactory, potential risks of relying on the adult-based emergency transportation system were highlighted. A better system needs to be developed urgently to put appropriate priority on vulnerable infants. © 2017 S. Karger AG, Basel.

  10. Impact of the Great East Japan Earthquake on Body Mass Index, Weight, and Height of Infants and Toddlers: An Infant Survey.

    PubMed

    Yokomichi, Hiroshi; Matsubara, Hiroko; Ishikuro, Mami; Kikuya, Masahiro; Isojima, Tsuyoshi; Yokoya, Susumu; Kato, Noriko; Tanaka, Toshiaki; Chida, Shoichi; Ono, Atsushi; Hosoya, Mitsuaki; Tanaka, Soichiro; Kuriyama, Shinichi; Kure, Shigeo; Yamagata, Zentaro

    2018-05-05

    The body mass index (BMI) of preschool children from 4 years of age through primary school has increased since the Great East Japan Earthquake, but that of children aged under 3 years has not been studied. This study evaluated how the anthropometrics of younger children changed following the earthquake. Height and weight data of children living in northeast Japan were collected from 3-, 6-, 18-, and 42-month child health examinations. We compared the changes in BMI, weight, and height among infants affected by the earthquake between their 3- and 6-month health examinations, toddlers affected at 21-30 months of age (affected groups), and children who experienced the earthquake after their 42-month child health examination (unaffected group). A multilevel model was used to calculate the BMI at corresponding ages and to adjust for the actual age at the 3-month health examination, health examination interval, and gestational age. We recruited 8,479 boys and 8,218 girls living in Fukushima, Miyagi, and Iwate Prefectures. In the infants affected between their 3- and 6-month health examinations in Fukushima, the change in BMI at 42 months of age was greater than among the unaffected children. In the toddlers affected at 21-30 months of age in Fukushima, the change in BMI was greater, but changes in weight and height were less. Affected infants and toddlers in Fukushima suggested some growth disturbances and early adiposity rebound, which can cause obesity. The future growth of children affected by disasters should be followed carefully.

  11. Sleep Duration among Children 8 Months after the 2011 Japan Earthquake and Tsunami

    PubMed Central

    Usami, Masahide; Iwadare, Yoshitaka; Kodaira, Masaki; Watanabe, Kyota; Aoki, Momoko; Katsumi, Chiaki; Matsuda, Kumi; Makino, Kazunori; Iijima, Sonoko; Harada, Maiko; Tanaka, Hiromi; Sasaki, Yoshinori; Tanaka, Tetsuya; Ushijima, Hirokage; Saito, Kazuhiko

    2013-01-01

    Background To elucidate relationships between disaster damage conditions and sleep duration among children who survived the 2011 Japan earthquake and tsunami. Methods The subjects comprised 12,524 children in kindergartens, elementary schools, and junior high schools in Ishinomaki City, Miyagi Prefecture, Japan. The Post Traumatic Stress Symptoms for Children 15 items (PTSSC-15), a self-completion questionnaire on traumatic symptoms, and a sleep questionnaire were distributed to them. A questionnaire regarding disaster damage conditions of the children’s homes was distributed to their teachers. Of 12,524, an effective response was obtained from 11,692 (93.3%). Results Relationships between sleep duration and traumatic symptoms were displayed low correlations. Children with house damage and/or evacuation experiences slept for a significantly shorter time than children without these experiences. Conclusion It is critical not only to examine traumatic symptoms in children but also to collect sleep duration and disaster damage conditions following natural disasters. PMID:23738015

  12. The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence

    USGS Publications Warehouse

    Coordinated by Bakun, William H.; Prescott, William H.

    1993-01-01

    Professional Paper 1550 seeks to understand the M6.9 Loma Prieta earthquake itself. It examines how the fault that generated the earthquake ruptured, searches for and evaluates precursors that may have indicated an earthquake was coming, reviews forecasts of the earthquake, and describes the geology of the earthquake area and the crustal forces that affect this geology. Some significant findings were: * Slip during the earthquake occurred on 35 km of fault at depths ranging from 7 to 20 km. Maximum slip was approximately 2.3 m. The earthquake may not have released all of the strain stored in rocks next to the fault and indicates a potential for another damaging earthquake in the Santa Cruz Mountains in the near future may still exist. * The earthquake involved a large amount of uplift on a dipping fault plane. Pre-earthquake conventional wisdom was that large earthquakes in the Bay area occurred as horizontal displacements on predominantly vertical faults. * The fault segment that ruptured approximately coincided with a fault segment identified in 1988 as having a 30% probability of generating a M7 earthquake in the next 30 years. This was one of more than 20 relevant earthquake forecasts made in the 83 years before the earthquake. * Calculations show that the Loma Prieta earthquake changed stresses on nearby faults in the Bay area. In particular, the earthquake reduced stresses on the Hayward Fault which decreased the frequency of small earthquakes on it. * Geological and geophysical mapping indicate that, although the San Andreas Fault can be mapped as a through going fault in the epicentral region, the southwest dipping Loma Prieta rupture surface is a separate fault strand and one of several along this part of the San Andreas that may be capable of generating earthquakes.

  13. PAGER--Rapid assessment of an earthquake?s impact

    USGS Publications Warehouse

    Wald, D.J.; Jaiswal, K.; Marano, K.D.; Bausch, D.; Hearne, M.

    2010-01-01

    PAGER (Prompt Assessment of Global Earthquakes for Response) is an automated system that produces content concerning the impact of significant earthquakes around the world, informing emergency responders, government and aid agencies, and the media of the scope of the potential disaster. PAGER rapidly assesses earthquake impacts by comparing the population exposed to each level of shaking intensity with models of economic and fatality losses based on past earthquakes in each country or region of the world. Earthquake alerts--which were formerly sent based only on event magnitude and location, or population exposure to shaking--now will also be generated based on the estimated range of fatalities and economic losses.

  14. Horticultural therapy as a measure for recovery support of regional community in the disaster area: a preliminary experiment for forty five women who living certain region in the coastal area of Miyagi Prefecture.

    PubMed

    Kotozaki, Yuka

    2014-01-01

    Three years have passed since the earthquake, in the coastal areas in the disaster area, by population transfer or the like from the temporary housing, the importance of the regeneration and revitalization of the local community has been pointed out. This study performed a preliminary study to aim at the psychological inspection about an effect of the horticultural therapy as the means of the local community reproduction support of the disaster area. Forty five women who are living in the coastal area of Miyagi Prefecture participated in this study. They experienced the Great East Japan earthquake in 2011 and suffered some kind of damage caused by the earthquake. The participants were assigned to two groups, the intervention group and the control group, via a random draw using a computer. The HI group attended the horticultural therapy intervention (HT intervention) sessions for 16 weeks. The HT intervention was designed in collaboration with a horticultural therapist and clinical psychologists. This intervention comprised a total of 16 weekly sessions (120 min each) at the community center and 15 minutes per day at participants' homes. We used five psychological measures for an intervention evaluation. The HI group showed a significant increase in post- intervention SCI-2 total scores, post- intervention SCI-2 membership scores, post-intervention SCI-2 influence scores, post- intervention SCI-2 meeting needs scores, post- intervention SCI-2 shared emotional connection scores, and post- intervention RSES score. We believe that these results suggest the effectiveness of the horticultural therapy as the means of the local community reproduction.

  15. The Great Tohoku-Oki Earthquake and Tsunami of March 11, 2011 in Japan: A Critical Review and Evaluation of the Tsunami Source Mechanism

    NASA Astrophysics Data System (ADS)

    Pararas-Carayannis, George

    2014-12-01

    The great Tohoku-Oki earthquake of March 11, 2011 generated a very destructive and anomalously high tsunami. To understand its source mechanism, an examination was undertaken of the seismotectonics of the region and of the earthquake's focal mechanism, energy release, rupture patterns and spatial and temporal sequencing and clustering of major aftershocks. It was determined that the great tsunami resulted from a combination of crustal deformations of the ocean floor due to up-thrust tectonic motions, augmented by additional uplift due to the quake's slow and long rupturing process, as well as to large coseismic lateral movements which compressed and deformed the compacted sediments along the accretionary prism of the overriding plane. The deformation occurred randomly and non-uniformly along parallel normal faults and along oblique, en-echelon faults to the earthquake's overall rupture direction—the latter failing in a sequential bookshelf manner with variable slip angles. As the 1992 Nicaragua and the 2004 Sumatra earthquakes demonstrated, such bookshelf failures of sedimentary layers could contribute to anomalously high tsunamis. As with the 1896 tsunami, additional ocean floor deformation and uplift of the sediments was responsible for the higher waves generated by the 2011 earthquake. The efficiency of tsunami generation was greater along the shallow eastern segment of the fault off the Miyagi Prefecture where most of the energy release of the earthquake and the deformations occurred, while the segment off the Ibaraki Prefecture—where the rupture process was rapid—released less seismic energy, resulted in less compaction and deformation of sedimentary layers and thus to a tsunami of lesser offshore height. The greater tsunamigenic efficiency of the 2011 earthquake and high degree of the tsunami's destructiveness along Honshu's coastlines resulted from vertical crustal displacements of more than 10 m due to up-thrust faulting and from lateral compression

  16. [Subsidized project of hearing aid purchase for mild-moderate hearing impaired children in Akita prefecture].

    PubMed

    Sato, Teruyuki; Nakazawa, Misao; Takahashi, Shin; Ishikawa, Kazuo

    2013-06-01

    The dissemination of newborn hearing screening has detected children with mild-moderate hearing impairment at an early age. However, there is no nation-wide welfare system for children with mild-moderate hearing impairment in Japan. Under these kinds of social conditions, a subsidized project of hearing aid purchase for mild-moderate hearing impaired children has come into force from April 2010 in Akita prefecture. All 18 candidates who applied for this project were subsidized in Akita prefecture. Eighteen children purchased their hearing aids using this subsidy. The feature of this project was that every child could have access to subsidies as long as their doctor recognized the effectiveness of hearing aids because children with hearing impairment need to learn language. They contacted the hospital, prefectural government and institutes related to hearing loss before this project come into force. We recognized parents who are raising a child with mild-moderate hearing impairment have high interest in this project. Hearing aids can represent a considerable expense for young parents who are raising a child. We encountered some children who had to give up the idea of hearing aids due to their parents' economic circumstances before this project become effective. These situations were completely avoided after this project came into being. This administrative purpose was of demonstrated value in children with mild-moderate hearing impairment.

  17. Underestimation of Microearthquake Size by the Magnitude Scale of the Japan Meteorological Agency: Influence on Earthquake Statistics

    NASA Astrophysics Data System (ADS)

    Uchide, Takahiko; Imanishi, Kazutoshi

    2018-01-01

    Magnitude scales based on the amplitude of seismic waves, including the Japan Meteorological Agency magnitude scale (Mj), are commonly used in routine processes. The moment magnitude scale (Mw), however, is more physics based and is able to evaluate any type and size of earthquake. This paper addresses the relation between Mj and Mw for microearthquakes. The relative moment magnitudes among earthquakes are well constrained by multiple spectral ratio analyses. The results for the events in the Fukushima Hamadori and northern Ibaraki prefecture areas of Japan imply that Mj is significantly and systematically smaller than Mw for microearthquakes. The Mj-Mw curve has slopes of 1/2 and 1 for small and large values of Mj, respectively; for example, Mj = 1.0 corresponds to Mw = 2.0. A simple numerical simulation implies that this is due to anelastic attenuation and the recording using a finite sampling interval. The underestimation affects earthquake statistics. The completeness magnitude, Mc, for magnitudes lower than which the magnitude-frequency distribution deviates from the Gutenberg-Richter law, is effectively lower for Mw than that for Mj, by taking into account the systematic difference between Mj and Mw. The b values of the Gutenberg-Richter law are larger for Mw than for Mj. As the b values for Mj and Mw are well correlated, qualitative argument using b values is not affected. While the estimated b values for Mj are below 1.5, those for Mw often exceed 1.5. This may affect the physical implication of the seismicity.

  18. Operational earthquake forecasting can enhance earthquake preparedness

    USGS Publications Warehouse

    Jordan, T.H.; Marzocchi, W.; Michael, A.J.; Gerstenberger, M.C.

    2014-01-01

    We cannot yet predict large earthquakes in the short term with much reliability and skill, but the strong clustering exhibited in seismic sequences tells us that earthquake probabilities are not constant in time; they generally rise and fall over periods of days to years in correlation with nearby seismic activity. Operational earthquake forecasting (OEF) is the dissemination of authoritative information about these time‐dependent probabilities to help communities prepare for potentially destructive earthquakes. The goal of OEF is to inform the decisions that people and organizations must continually make to mitigate seismic risk and prepare for potentially destructive earthquakes on time scales from days to decades. To fulfill this role, OEF must provide a complete description of the seismic hazard—ground‐motion exceedance probabilities as well as short‐term rupture probabilities—in concert with the long‐term forecasts of probabilistic seismic‐hazard analysis (PSHA).

  19. Inter-prefecture disparity in under-5 mortality: 115 year trend in Japan.

    PubMed

    Nagata, Chie; Moriichi, Akinori; Morisaki, Naho; Gai-Tobe, Ruoyan; Ishiguro, Akira; Mori, Rintaro

    2017-07-01

    Child poverty is a growing, serious issue in Japan, where various social disparities are increasing. Numerous reports have focused on the relationship between social inequity and health, but few studies have assessed how the overall magnitude of disparities in child health has changed in the course of drastic social and economic transitions from 1899 to more recent times. In this study, we assessed the trend of the under-5 mortality rate (U5MR) and its inter-prefecture disparity in Japan. This is a secondary analysis of Japan's vital statistics data from 1899 to 2014 (115 years), which covers a core period of modern Japan. We calculated the U5MR of each prefecture and its Theil index by year to assess the trend of inter-prefecture disparity in child health from 1899 to 2014. The U5MR monotonically decreased from 238 per 1,000 births in 1899 to 3 in 2014. The Theil index of the U5MR increased in the post-war period, peaked in 1962 (0.027) and gradually reduced to <0.01 in the 1970s. In the 2000s, however, even though U5MR continued to decrease, the Theil index started to increase, and in 2014 (0.013) it exceeded that in 1970 and was more similar to that before World War II. The disparities in child health appear to be widening, and may serve as a warning to today's society that increasing socioeconomic gradients may lead to rising health inequity among children. Further investigations into the causes, mechanisms, and possible interventions are needed. © 2017 Japan Pediatric Society.

  20. Earthquakes for Kids

    MedlinePlus

    ... across a fault to learn about past earthquakes. Science Fair Projects A GPS instrument measures slow movements of the ground. Become an Earthquake Scientist Cool Earthquake Facts Today in Earthquake History A scientist stands in ...

  1. Evaluation of awareness and preparedness of school Principals and teachers on earthquake reduction effects issues - State's actions

    NASA Astrophysics Data System (ADS)

    Kourou, Assimina; Ioakeimidou, Anastasia; Mokos, Vasileios; Bakas, Konstantinos

    2013-04-01

    primary and secondary schools of 9 different prefectures of Greece. Approximately 1.100 responses have been gathered. The analysis of the results indicated that approximately 60% of the surveyed teachers have experienced at least one earthquake at school, which is expected due to Greece's high seismicity (50% of the released seismic energy in Europe). Additionally, the level of knowledge of surveyed teachers on earthquake protection measures is very high. A significant majority of the teachers, were reported being familiar with the identification and reduction of non structural hazards at their home, and the development of School's Emergency Plans. On the other hand, approximately the 25% of the responders were not aware of their school emergency plan or they claimed that such a plan does not exist at their schools. These teachers have not participated in any earthquake school drill. Thus, even though a lot of State's initiatives have been implemented till now to build awareness towards earthquakes and establish a preparedness status for prospective earthquakes in school community, there are still proposed actions to be taken in order to improve the teachers' ability to plan or implement activities concerning earthquake management issues.

  2. Foreign Language Curricula in Japanese High Schools: A Case Study in Miyagi Prefecture

    ERIC Educational Resources Information Center

    Ball, Daniel

    2007-01-01

    The purpose of this study was to examine the foreign language curricula in Japanese high schools for the purpose of gaining insight into alternative views of foreign language education. Teachers, administrators, and staff at two high schools in Miyagi Prefecture were interviewed. Teachers were asked about testing, placement procedures, standards,…

  3. Early detection and response for measles and rubella cases through the (Nursery) School Absenteeism Surveillance System in Ibaraki Prefecture.

    PubMed

    Watanabe, Miki; Kurita, Junko; Takagi, Takeshi; Nagata, Noriko; Nagasu, Natsuki; Sugawara, Tamie; Ohkusa, Yasushi

    2016-01-01

    Objectives In Ibaraki Prefecture, all (nursery) schools have joined the (Nursery) School Absenteeism Surveillance System (hereafter denoted as (N)SASSy), which is operated by the Japan School Health Association to monitor the prevalence of infectious diseases, the early detection and response for outbreaks, and prevention of large outbreaks. Prefectural government officers also utilize it as a control measure for infectious diseases. In particular, when cases of measles or rubella are registered, (N)SASSy sends e-mails automatically to prefectural government officers to activate control measures. This paper summarizes administrative responses by prefectural government officers for measles or rubella cases using (N)SASSy and discusses the future challenges.Methods We summarized registration, detection, and first response data for measles or rubella cases in (N)SASSy and compared the number of detected and reported cases enforced by the Infectious Diseases Control Law from January 1, 2013 to December 31, 2014.Results The public health center questioned hospitals/clinics and (nursery) schools about all registered measles or rubella cases in (N)SASSy on the same day to check the entered information. In the past 2 years, there were 5 measles and 56 rubella cases in 2013 and 1 measles and 19 rubella cases in 2014 registered with (N)SASSy. All cases were checked and investigated by the public health center. Of all cases detected by (N)SASSy, 7 rubella cases in 2013 and 1 rubella case in 2014 were reported based on the law. No measles cases were reported in the 2 years. The results of investigations and laboratory tests were given as feedback to the (nursery) schools. If the case did not case definition determined by the law, we changed the status in (N)SASSy to suspected or discarded cases.Conclusion Since (N)SASSy assists prefectural government officers with earlier detection of and response for infectious diseases, it definitely contributes to infection control

  4. Impact of the Great East Japan Earthquake on Hotel Industry in Pacific Tohoku Prefectures ---From Spatio-Temporal Dependence of Hotel Availability---

    NASA Astrophysics Data System (ADS)

    Sato, A.

    This paper investigates the impact of the Great Japan Earthquake(and subsequent tsunami turmoil) on socio-economic activities by using data on hotel opportunities collected from an electronic hotel booking service. A method to estimate both primary and secondary regional effects of a natural disaster on human behavior is proposed. It is confirmed that temporal variation in the regional share of available hotels before and after a natural disaster may be an indicator to measure the socio-economic impact at each district.

  5. Daily radionuclide ingestion and internal radiation doses in Aomori prefecture, Japan.

    PubMed

    Ohtsuka, Yoshihito; Kakiuchi, Hideki; Akata, Naofumi; Takaku, Yuichi; Hisamatsu, Shun'ichi

    2013-10-01

    To assess internal annual dose in the general public in Aomori Prefecture, Japan, 80 duplicate cooked diet samples, equivalent to the food consumed over a 400-d period by one person, were collected from 100 volunteers in Aomori City and the village of Rokkasho during 2006–2010 and were analyzed for 11 radionuclides. To obtain average rates of ingestion of radionuclides, the volunteers were selected from among office, fisheries, agricultural, and livestock farm workers. Committed effective doses from ingestion of the diet over a 1-y period were calculated from the analytical results and from International Commission on Radiological Protection dose coefficients; for 40K, an internal effective dose rate from the literature was used. Fisheries workers had significantly higher combined internal annual dose than the other workers, possibly because of high rates of ingestion of marine products known to have high 210Po concentrations. The average internal dose rate, weighted by the numbers of households in each worker group in Aomori Prefecture, was estimated at 0.47 mSv y-1. Polonium-210 contributed 49% of this value. The sum of committed effective dose rates for 210Po, 210Pb, 228Ra, and 14C and the effective dose rate of 40K accounted for approximately 99% of the average internal dose rate.

  6. Foreshock search over a long duration using a method of setting appropriate criteria

    NASA Astrophysics Data System (ADS)

    Toyomoto, Y.; Kawakata, H.; Hirano, S.; Doi, I.

    2016-12-01

    Recently, small foreshocks have been detected using cross-correlation techniques (e.g., Bouchon et al., 2011) in which the foreshocks are identified when the cross-correlation coefficient (CC) exceeded a certain threshold. For some shallow intraplate earthquakes, foreshocks whose hypocenters were estimated to be adjacent to the main shock hypocenter were detected from several tens of minutes before the main shock occurrence (Doi and Kawakata, 2012; 2013). At least two problems remain in the cross-correlation techniques employed. First, previous studies on foreshocks used data whose durations are at most a month (Kato et al., 2013); this is insufficient to check if such events occurred only before the main shock occurrence or not. Second, CC is used for detection criteria without considering validity of the threshold. In this study, we search for foreshocks of an M 5.4 earthquake in central Nagano prefecture in Japan on June 30, 2011 with a vertical-component waveform at N.MWDH (Hi-net) station due to one of the cataloged foreshocks (M 1) as a template to calculate CC. We calculate CC between the template and continuous waveforms of the same component at the same station for two years before the main shock occurrence, and we try to overcome the problems mentioned above. We find that histogram of CC is well modeled with the normal distribution, which is similar to previous studies on tremors (e.g., Ohta and Ide, 2008). According to the model, the expected number of misdetection is less than 1 when CC > 0.63. Therefore, we regard that the waveform is due to a foreshock when CC > 0.63. As a result, foreshocks are detected only within thirteen hours immediately before the main shock occurrence for the two years. By setting an appropriate threshold, we conclude that foreshocks just before the main shock occurrence are not stationary events. Acknowledgments: We use continuous waveform records of NIED high sensitivity seismograph network in Japan (Hi-net) and the JMA

  7. Tree Species Classification of Broadleaved Forests in Nagano, Central Japan, Using Airborne Laser Data and Multispectral Images

    NASA Astrophysics Data System (ADS)

    Deng, S.; Katoh, M.; Takenaka, Y.; Cheung, K.; Ishii, A.; Fujii, N.; Gao, T.

    2017-10-01

    This study attempted to classify three coniferous and ten broadleaved tree species by combining airborne laser scanning (ALS) data and multispectral images. The study area, located in Nagano, central Japan, is within the broadleaved forests of the Afan Woodland area. A total of 235 trees were surveyed in 2016, and we recorded the species, DBH, and tree height. The geographical position of each tree was collected using a Global Navigation Satellite System (GNSS) device. Tree crowns were manually detected using GNSS position data, field photographs, true-color orthoimages with three bands (red-green-blue, RGB), 3D point clouds, and a canopy height model derived from ALS data. Then a total of 69 features, including 27 image-based and 42 point-based features, were extracted from the RGB images and the ALS data to classify tree species. Finally, the detected tree crowns were classified into two classes for the first level (coniferous and broadleaved trees), four classes for the second level (Pinus densiflora, Larix kaempferi, Cryptomeria japonica, and broadleaved trees), and 13 classes for the third level (three coniferous and ten broadleaved species), using the 27 image-based features, 42 point-based features, all 69 features, and the best combination of features identified using a neighborhood component analysis algorithm, respectively. The overall classification accuracies reached 90 % at the first and second levels but less than 60 % at the third level. The classifications using the best combinations of features had higher accuracies than those using the image-based and point-based features and the combination of all of the 69 features.

  8. Missing great earthquakes

    USGS Publications Warehouse

    Hough, Susan E.

    2013-01-01

    The occurrence of three earthquakes with moment magnitude (Mw) greater than 8.8 and six earthquakes larger than Mw 8.5, since 2004, has raised interest in the long-term global rate of great earthquakes. Past studies have focused on the analysis of earthquakes since 1900, which roughly marks the start of the instrumental era in seismology. Before this time, the catalog is less complete and magnitude estimates are more uncertain. Yet substantial information is available for earthquakes before 1900, and the catalog of historical events is being used increasingly to improve hazard assessment. Here I consider the catalog of historical earthquakes and show that approximately half of all Mw ≥ 8.5 earthquakes are likely missing or underestimated in the 19th century. I further present a reconsideration of the felt effects of the 8 February 1843, Lesser Antilles earthquake, including a first thorough assessment of felt reports from the United States, and show it is an example of a known historical earthquake that was significantly larger than initially estimated. The results suggest that incorporation of best available catalogs of historical earthquakes will likely lead to a significant underestimation of seismic hazard and/or the maximum possible magnitude in many regions, including parts of the Caribbean.

  9. Analog earthquakes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hofmann, R.B.

    1995-09-01

    Analogs are used to understand complex or poorly understood phenomena for which little data may be available at the actual repository site. Earthquakes are complex phenomena, and they can have a large number of effects on the natural system, as well as on engineered structures. Instrumental data close to the source of large earthquakes are rarely obtained. The rare events for which measurements are available may be used, with modfications, as analogs for potential large earthquakes at sites where no earthquake data are available. In the following, several examples of nuclear reactor and liquified natural gas facility siting are discussed.more » A potential use of analog earthquakes is proposed for a high-level nuclear waste (HLW) repository.« less

  10. Turkish Compulsory Earthquake Insurance and "Istanbul Earthquake

    NASA Astrophysics Data System (ADS)

    Durukal, E.; Sesetyan, K.; Erdik, M.

    2009-04-01

    The city of Istanbul will likely experience substantial direct and indirect losses as a result of a future large (M=7+) earthquake with an annual probability of occurrence of about 2%. This paper dwells on the expected building losses in terms of probable maximum and average annualized losses and discusses the results from the perspective of the compulsory earthquake insurance scheme operational in the country. The TCIP system is essentially designed to operate in Turkey with sufficient penetration to enable the accumulation of funds in the pool. Today, with only 20% national penetration, and about approximately one-half of all policies in highly earthquake prone areas (one-third in Istanbul) the system exhibits signs of adverse selection, inadequate premium structure and insufficient funding. Our findings indicate that the national compulsory earthquake insurance pool in Turkey will face difficulties in covering incurring building losses in Istanbul in the occurrence of a large earthquake. The annualized earthquake losses in Istanbul are between 140-300 million. Even if we assume that the deductible is raised to 15%, the earthquake losses that need to be paid after a large earthquake in Istanbul will be at about 2.5 Billion, somewhat above the current capacity of the TCIP. Thus, a modification to the system for the insured in Istanbul (or Marmara region) is necessary. This may mean an increase in the premia and deductible rates, purchase of larger re-insurance covers and development of a claim processing system. Also, to avoid adverse selection, the penetration rates elsewhere in Turkey need to be increased substantially. A better model would be introduction of parametric insurance for Istanbul. By such a model the losses will not be indemnified, however will be directly calculated on the basis of indexed ground motion levels and damages. The immediate improvement of a parametric insurance model over the existing one will be the elimination of the claim processing

  11. Earthquake potential revealed by tidal influence on earthquake size-frequency statistics

    NASA Astrophysics Data System (ADS)

    Ide, Satoshi; Yabe, Suguru; Tanaka, Yoshiyuki

    2016-11-01

    The possibility that tidal stress can trigger earthquakes is long debated. In particular, a clear causal relationship between small earthquakes and the phase of tidal stress is elusive. However, tectonic tremors deep within subduction zones are highly sensitive to tidal stress levels, with tremor rate increasing at an exponential rate with rising tidal stress. Thus, slow deformation and the possibility of earthquakes at subduction plate boundaries may be enhanced during periods of large tidal stress. Here we calculate the tidal stress history, and specifically the amplitude of tidal stress, on a fault plane in the two weeks before large earthquakes globally, based on data from the global, Japanese, and Californian earthquake catalogues. We find that very large earthquakes, including the 2004 Sumatran, 2010 Maule earthquake in Chile and the 2011 Tohoku-Oki earthquake in Japan, tend to occur near the time of maximum tidal stress amplitude. This tendency is not obvious for small earthquakes. However, we also find that the fraction of large earthquakes increases (the b-value of the Gutenberg-Richter relation decreases) as the amplitude of tidal shear stress increases. The relationship is also reasonable, considering the well-known relationship between stress and the b-value. This suggests that the probability of a tiny rock failure expanding to a gigantic rupture increases with increasing tidal stress levels. We conclude that large earthquakes are more probable during periods of high tidal stress.

  12. Understanding earthquake from the granular physics point of view — Causes of earthquake, earthquake precursors and predictions

    NASA Astrophysics Data System (ADS)

    Lu, Kunquan; Hou, Meiying; Jiang, Zehui; Wang, Qiang; Sun, Gang; Liu, Jixing

    2018-03-01

    We treat the earth crust and mantle as large scale discrete matters based on the principles of granular physics and existing experimental observations. Main outcomes are: A granular model of the structure and movement of the earth crust and mantle is established. The formation mechanism of the tectonic forces, which causes the earthquake, and a model of propagation for precursory information are proposed. Properties of the seismic precursory information and its relevance with the earthquake occurrence are illustrated, and principle of ways to detect the effective seismic precursor is elaborated. The mechanism of deep-focus earthquake is also explained by the jamming-unjamming transition of the granular flow. Some earthquake phenomena which were previously difficult to understand are explained, and the predictability of the earthquake is discussed. Due to the discrete nature of the earth crust and mantle, the continuum theory no longer applies during the quasi-static seismological process. In this paper, based on the principles of granular physics, we study the causes of earthquakes, earthquake precursors and predictions, and a new understanding, different from the traditional seismological viewpoint, is obtained.

  13. Redefining Earthquakes and the Earthquake Machine

    ERIC Educational Resources Information Center

    Hubenthal, Michael; Braile, Larry; Taber, John

    2008-01-01

    The Earthquake Machine (EML), a mechanical model of stick-slip fault systems, can increase student engagement and facilitate opportunities to participate in the scientific process. This article introduces the EML model and an activity that challenges ninth-grade students' misconceptions about earthquakes. The activity emphasizes the role of models…

  14. Toggling of seismicity by the 1997 Kagoshima earthquake couplet: A demonstration of time-dependent stress transfer

    USGS Publications Warehouse

    Toda, S.; Stein, R.

    2003-01-01

    Two M ??? 6 well-recorded strike-slip earthquakes struck just 4 km and 48 days apart in Kagoshima prefecture, Japan, in 1997, providing an opportunity to study earthquake interaction. Aftershocks are abundant where the Coulomb stress is calculated to have been increased by the first event, and they abruptly stop where the stress is dropped by the second event. This ability of the main shocks to toggle seismicity on and off argues that static stress changes play a major role in exciting aftershocks, whereas the dynamic Coulomb stresses, which should only promote seismicity, appear to play a secondary role. If true, the net stress changes from a sequence of earthquakes might be expected to govern the subsequent seismicity distribution. However, adding the stress changes from the two Kagoshima events does not fully capture the ensuing seismicity, such as its rate change, temporal decay, or migration away from the ends of the ruptures. We therefore implement a stress transfer model that incorporates rate/state friction, in which seismicity is treated as a sequence of independent nucleation events that are dependent on the fault slip, slip rate, and elapsed time since the last event. The model reproduces the temporal response of seismicity to successive stress changes, including toggling, decay, and aftershock migration. Nevertheless, the match of observed to predicted seismicity is quite imperfect, due perhaps to inadequate knowledge of several model parameters. However, to demonstrate the potential of this approach, we build a probabilistic forecast of larger earthquakes on the expected rate of small aftershocks, taking advantage of the large statistical sample the small shocks afford. Not surprisingly, such probabilities are highly time- and location-dependent: During the first decade after the main shocks, the seismicity rate and the chance of successive large shocks are about an order of magnitude higher than the background rate and are concentrated exclusively in

  15. E55_Inflight_JAXA_Gifu_Prefecture__2018_0529_1112_659069

    NASA Image and Video Library

    2018-05-30

    SPACE STATION CREW MEMBER DISCUSSES LIFE IN SPACE WITH JAPANESE STUDENTS--- Aboard the International Space Station, Expedition 55 Flight Engineer Norishige Kanai of the Japan Aerospace Exploration Agency (JAXA) discussed life and space on the orbital outpost during an in-flight educational event May 29 with students gathered at the Gifu Prefecture Air and Space Museum in Japan. Kanai is in the final week of his six month mission on the complex, headed for a landing in a Russian Soyuz spacecraft June 3 on the south central steppe of Kazakhstan.

  16. Deep venous thrombosis among disaster shelter inhabitants following the March 2011 earthquake and tsunami in Japan: a descriptive study.

    PubMed

    Shibata, M; Hanzawa, K; Ueda, S; Yambe, T

    2014-05-01

    A retrospective analysis of data collected during subject screening following Japan's March 2011 earthquake and tsunami was performed. We aimed to determine the incidence of deep venous thrombosis (DVT) among screened subjects and to identify risk factors associated with the development of DVT as independent variables. Calf ultrasonography was undertaken in 269 subjects living in 21 shelters in Miyagi prefecture during the one-month period immediately following the March 2011 disaster. Information regarding the health and risk factors of subjects was collected by questionnaire and assessment of physical signs. Of the 269 evacuees screened, 65 (24%) met the criteria for calf DVT. We found lower limb trauma, reduced frequency of urination and sleeping in a vehicle to be independent positive predictors of DVT. Evacuees had an increased risk of developing DVT, associated with tsunami-related lower limb injury, immobility and dehydration.

  17. OMG Earthquake! Can Twitter improve earthquake response?

    NASA Astrophysics Data System (ADS)

    Earle, P. S.; Guy, M.; Ostrum, C.; Horvath, S.; Buckmaster, R. A.

    2009-12-01

    The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public, text messages, can augment its earthquake response products and the delivery of hazard information. The goal is to gather near real-time, earthquake-related messages (tweets) and provide geo-located earthquake detections and rough maps of the corresponding felt areas. Twitter and other social Internet technologies are providing the general public with anecdotal earthquake hazard information before scientific information has been published from authoritative sources. People local to an event often publish information within seconds via these technologies. In contrast, depending on the location of the earthquake, scientific alerts take between 2 to 20 minutes. Examining the tweets following the March 30, 2009, M4.3 Morgan Hill earthquake shows it is possible (in some cases) to rapidly detect and map the felt area of an earthquake using Twitter responses. Within a minute of the earthquake, the frequency of “earthquake” tweets rose above the background level of less than 1 per hour to about 150 per minute. Using the tweets submitted in the first minute, a rough map of the felt area can be obtained by plotting the tweet locations. Mapping the tweets from the first six minutes shows observations extending from Monterey to Sacramento, similar to the perceived shaking region mapped by the USGS “Did You Feel It” system. The tweets submitted after the earthquake also provided (very) short first-impression narratives from people who experienced the shaking. Accurately assessing the potential and robustness of a Twitter-based system is difficult because only tweets spanning the previous seven days can be searched, making a historical study impossible. We have, however, been archiving tweets for several months, and it is clear that significant limitations do exist. The main drawback is the lack of quantitative information

  18. [Family influences on future smoking habits among junior high school students in Japan].

    PubMed

    Wakabayashi, Chihiro

    2007-11-01

    To examine the effects of health-related behavior and family smoking habits on the future smoking habits of junior high school students in two Japanese cities with different life expectancies. A cross-sectional study was conducted in January 2005 of all second-grade students in a junior high school in city A located in Aomori prefecture (399 students) and city B located in Nagano prefecture (447 students). Life expectancies in city B were 4.2 years longer in men and 2.9 years longer in women than in city A. Data on feelings about future smoking habits, dislike of tobacco smoke, family smoking habits and health-related behavior were collected. The proportion of boys who went on to become smokers was higher in city A (18.7%) than in city B (10.3%). The proportions of smoking mothers and other smoking family members were also higher in city A, while the proportion of students who disliked tobacco smoke was lower. For girls in both cities, there was a significant positive association between future smoking and maternal smoking. The findings suggest that maternal smoking habits are especially strongly correlated with future smoking in girls. The family smoking environment and health-related behavior should therefore be considered in measures to prevent smoking by students.

  19. Twitter earthquake detection: Earthquake monitoring in a social world

    USGS Publications Warehouse

    Earle, Paul S.; Bowden, Daniel C.; Guy, Michelle R.

    2011-01-01

    The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public text messages, can augment USGS earthquake response products and the delivery of hazard information. Rapid detection and qualitative assessment of shaking events are possible because people begin sending public Twitter messages (tweets) with in tens of seconds after feeling shaking. Here we present and evaluate an earthquake detection procedure that relies solely on Twitter data. A tweet-frequency time series constructed from tweets containing the word "earthquake" clearly shows large peaks correlated with the origin times of widely felt events. To identify possible earthquakes, we use a short-term-average, long-term-average algorithm. When tuned to a moderate sensitivity, the detector finds 48 globally-distributed earthquakes with only two false triggers in five months of data. The number of detections is small compared to the 5,175 earthquakes in the USGS global earthquake catalog for the same five-month time period, and no accurate location or magnitude can be assigned based on tweet data alone. However, Twitter earthquake detections are not without merit. The detections are generally caused by widely felt events that are of more immediate interest than those with no human impact. The detections are also fast; about 75% occur within two minutes of the origin time. This is considerably faster than seismographic detections in poorly instrumented regions of the world. The tweets triggering the detections also provided very short first-impression narratives from people who experienced the shaking.

  20. Development of regional earthquake early warning and structural health monitoring system and real-time ground motion forecasting using front-site waveform data (Invited)

    NASA Astrophysics Data System (ADS)

    Motosaka, M.

    2009-12-01

    This paper presents firstly, the development of an integrated regional earthquake early warning (EEW) system having on-line structural health monitoring (SHM) function, in Miyagi prefecture, Japan. The system makes it possible to provide more accurate, reliable and immediate earthquake information for society by combining the national (JMA/NIED) EEW system, based on advanced real-time communication technology. The author has planned to install the EEW/SHM system to the public buildings around Sendai, a million city of north-eastern Japan. The system has been so far implemented in two buildings; one is in Sendai, and the other in Oshika, a front site on the Pacific Ocean coast for the approaching Miyagi-ken Oki earthquake. The data from the front-site and the on-site are processed by the analysis system which was installed at the analysis center of Disaster Control Research Center, Tohoku University. The real-time earthquake information from JMA is also received at the analysis center. The utilization of the integrated EEW/SHM system is addressed together with future perspectives. Examples of the obtained data are also described including the amplitude depending dynamic characteristics of the building in Sendai before, during, and after the 2008/6/14 Iwate-Miyagi Nairiku Earthquake, together with the historical change of dynamic characteristics for 40 years. Secondary, this paper presents an advanced methodology based on Artificial Neural Networks (ANN) for forward forecasting of ground motion parameters, not only PGA, PGV, but also Spectral information before S-wave arrival using initial part of P-waveform at a front site. The estimated ground motion information can be used as warning alarm for earthquake damage reduction. The Fourier Amplitude Spectra (FAS) estimated before strong shaking with high accuracy can be used for advanced engineering applications, e.g. feed-forward structural control of a building of interest. The validity and applicability of the method

  1. TRANSFORMATION FACTORS OF ENVIRONMENTAL CONSCIOUSNESS AND ACTION IN IIDA CITY RESIDENTS - ATTEITION TO ENVIRONMENTAL MEASURES AND SOCIAL CAPITAL

    NASA Astrophysics Data System (ADS)

    Shirai, Nobuo; Higuchi, Kazukiyo; Tokai, Akihiro

    Iida City in Nagano Prefecture is a town with an advanced environmental strategy including citizenry participation in the town's environment plan, a network of EMS (Environmental Management system) businesses, and a citizens' solar power system. In this study, a questionnaire of Iida residents was carried out to determine their environmental consciousness, and the effect on their actions. It also examined the influence of current environmental measures on the residents, and the relation between the level of social capital and residents' environmental considerations. The results indicate that the environmental consideration level of the senior citizen group is higher than that of the entire Japan in Iida City, and environmental measures has improved the residents' environmental consciousness. And it is thought the environmental consideration level of the senior citizen group is related to the level of social capital.

  2. Spectroscopic characterization of manganese minerals.

    PubMed

    Lakshmi Reddy, S; Padma Suvarna, K; Udayabhaska Reddy, G; Endo, Tamio; Frost, R L

    2014-01-03

    Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.0. Optical absorption spectrum of the mineral alleghanyite indicates that Mn(II) is present in two different octahedral sites and in leucophoenicite Mn(II) is also in octahedral geometry. Ardenite mineral gives only a few Mn(II) bands. NIR results of the minerals ardenite, leucophoenicite and alleghanyite are due to hydroxyl and silicate anions which confirming the formulae of the minerals. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Crustal earthquake triggering by pre-historic great earthquakes on subduction zone thrusts

    USGS Publications Warehouse

    Sherrod, Brian; Gomberg, Joan

    2014-01-01

    Triggering of earthquakes on upper plate faults during and shortly after recent great (M>8.0) subduction thrust earthquakes raises concerns about earthquake triggering following Cascadia subduction zone earthquakes. Of particular regard to Cascadia was the previously noted, but only qualitatively identified, clustering of M>~6.5 crustal earthquakes in the Puget Sound region between about 1200–900 cal yr B.P. and the possibility that this was triggered by a great Cascadia thrust subduction thrust earthquake, and therefore portends future such clusters. We confirm quantitatively the extraordinary nature of the Puget Sound region crustal earthquake clustering between 1200–900 cal yr B.P., at least over the last 16,000. We conclude that this cluster was not triggered by the penultimate, and possibly full-margin, great Cascadia subduction thrust earthquake. However, we also show that the paleoseismic record for Cascadia is consistent with conclusions of our companion study of the global modern record outside Cascadia, that M>8.6 subduction thrust events have a high probability of triggering at least one or more M>~6.5 crustal earthquakes.

  4. Comparison of cardiovascular mortality in the Great East Japan and the Great Hanshin-Awaji Earthquakes - a large-scale data analysis of death certificates.

    PubMed

    Takegami, Misa; Miyamoto, Yoshihiro; Yasuda, Satoshi; Nakai, Michikazu; Nishimura, Kunihiro; Ogawa, Hisao; Hirata, Ken-Ichi; Toh, Ryuji; Morino, Yoshihiro; Nakamura, Motoyuki; Takeishi, Yasuchika; Shimokawa, Hiroaki; Naito, Hiroaki

    2015-01-01

    Large earthquakes have been associated with cardiovascular disease (CVD) mortality. In Japan, the 1995 Great Hanshin-Awaji (H-A) Earthquake was an urban-underground-type earthquake, whereas the 2011 Great East Japan (GEJ) Earthquake was an ocean-trench type. In the present study, we examined how these different earthquake types affected CVD mortality. We examined death certificate data from 2008 to 2012 for 131 municipalities in Iwate, Miyagi, and Fukushima prefectures (n=320,348) and from 1992 to 1996 for 220 municipalities in Hyogo, Osaka, and Kyoto prefectures (n=592,670). A Poisson regression model showed significant increases in the monthly numbers of acute myocardial infarction (AMI)-related deaths (incident rate ratio [IRR] GEJ=1.34, P=0.001; IRR of H-A=1.57, P<0.001) and stroke-related deaths (IRR of GEJ=1.42, P<0.001; IRR of H-A=1.33, P<0.001) after the earthquakes. Two months after the earthquakes, AMI deaths remained significant only for H-A (IRR=1.13, P=0.029). When analyzing the standardized mortality ratio (SMR) after the earthquakes using the Cochran-Armitage trend test, seismic intensity was significantly associated with AMI mortality for 2 weeks after both the GEJ (P for trend=0.089) and H-A earthquakes (P for trend=0.005). Following the GEJ and H-A earthquakes, there was a sharp increase in CVD mortality. The effect of the disaster was sustained for months after the H-A earthquake, but was diminished after the GEJ Earthquake.

  5. Impact of earthquakes on sex ratio at birth: Eastern Marmara earthquakes

    PubMed Central

    Doğer, Emek; Çakıroğlu, Yiğit; Köpük, Şule Yıldırım; Ceylan, Yasin; Şimşek, Hayal Uzelli; Çalışkan, Eray

    2013-01-01

    Objective: Previous reports suggest that maternal exposure to acute stress related to earthquakes affects the sex ratio at birth. Our aim was to examine the change in sex ratio at birth after Eastern Marmara earthquake disasters. Material and Methods: This study was performed using the official birth statistics from January 1997 to December 2002 – before and after 17 August 1999, the date of the Golcuk Earthquake – supplied from the Turkey Statistics Institute. The secondary sex ratio was expressed as the male proportion at birth, and the ratio of both affected and unaffected areas were calculated and compared on a monthly basis using data from gender with using the Chi-square test. Results: We observed significant decreases in the secondary sex ratio in the 4th and 8th months following an earthquake in the affected region compared to the unaffected region (p= 0.001 and p= 0.024). In the earthquake region, the decrease observed in the secondary sex ratio during the 8th month after an earthquake was specific to the period after the earthquake. Conclusion: Our study indicated a significant reduction in the secondary sex ratio after an earthquake. With these findings, events that cause sudden intense stress such as earthquakes can have an effect on the sex ratio at birth. PMID:24592082

  6. Large-Scale Earthquake Countermeasures Act and the Earthquake Prediction Council in Japan

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rikitake, T.

    1979-08-07

    The Large-Scale Earthquake Countermeasures Act was enacted in Japan in December 1978. This act aims at mitigating earthquake hazards by designating an area to be an area under intensified measures against earthquake disaster, such designation being based on long-term earthquake prediction information, and by issuing an earthquake warnings statement based on imminent prediction information, when possible. In an emergency case as defined by the law, the prime minister will be empowered to take various actions which cannot be taken at ordinary times. For instance, he may ask the Self-Defense Force to come into the earthquake-threatened area before the earthquake occurrence.more » A Prediction Council has been formed in order to evaluate premonitory effects that might be observed over the Tokai area, which was designated an area under intensified measures against earthquake disaster some time in June 1979. An extremely dense observation network has been constructed over the area.« less

  7. Foreshocks, aftershocks, and earthquake probabilities: Accounting for the landers earthquake

    USGS Publications Warehouse

    Jones, Lucile M.

    1994-01-01

    The equation to determine the probability that an earthquake occurring near a major fault will be a foreshock to a mainshock on that fault is modified to include the case of aftershocks to a previous earthquake occurring near the fault. The addition of aftershocks to the background seismicity makes its less probable that an earthquake will be a foreshock, because nonforeshocks have become more common. As the aftershocks decay with time, the probability that an earthquake will be a foreshock increases. However, fault interactions between the first mainshock and the major fault can increase the long-term probability of a characteristic earthquake on that fault, which will, in turn, increase the probability that an event is a foreshock, compensating for the decrease caused by the aftershocks.

  8. Earthquake catalog for estimation of maximum earthquake magnitude, Central and Eastern United States: Part B, historical earthquakes

    USGS Publications Warehouse

    Wheeler, Russell L.

    2014-01-01

    Computation of probabilistic earthquake hazard requires an estimate of Mmax: the moment magnitude of the largest earthquake that is thought to be possible within a specified geographic region. The region specified in this report is the Central and Eastern United States and adjacent Canada. Parts A and B of this report describe the construction of a global catalog of moderate to large earthquakes that occurred worldwide in tectonic analogs of the Central and Eastern United States. Examination of histograms of the magnitudes of these earthquakes allows estimation of Central and Eastern United States Mmax. The catalog and Mmax estimates derived from it are used in the 2014 edition of the U.S. Geological Survey national seismic-hazard maps. Part A deals with prehistoric earthquakes, and this part deals with historical events.

  9. Earthquake and tsunami forecasts: Relation of slow slip events to subsequent earthquake rupture

    PubMed Central

    Dixon, Timothy H.; Jiang, Yan; Malservisi, Rocco; McCaffrey, Robert; Voss, Nicholas; Protti, Marino; Gonzalez, Victor

    2014-01-01

    The 5 September 2012 Mw 7.6 earthquake on the Costa Rica subduction plate boundary followed a 62-y interseismic period. High-precision GPS recorded numerous slow slip events (SSEs) in the decade leading up to the earthquake, both up-dip and down-dip of seismic rupture. Deeper SSEs were larger than shallower ones and, if characteristic of the interseismic period, release most locking down-dip of the earthquake, limiting down-dip rupture and earthquake magnitude. Shallower SSEs were smaller, accounting for some but not all interseismic locking. One SSE occurred several months before the earthquake, but changes in Mohr–Coulomb failure stress were probably too small to trigger the earthquake. Because many SSEs have occurred without subsequent rupture, their individual predictive value is limited, but taken together they released a significant amount of accumulated interseismic strain before the earthquake, effectively defining the area of subsequent seismic rupture (rupture did not occur where slow slip was common). Because earthquake magnitude depends on rupture area, this has important implications for earthquake hazard assessment. Specifically, if this behavior is representative of future earthquake cycles and other subduction zones, it implies that monitoring SSEs, including shallow up-dip events that lie offshore, could lead to accurate forecasts of earthquake magnitude and tsunami potential. PMID:25404327

  10. Earthquake and tsunami forecasts: relation of slow slip events to subsequent earthquake rupture.

    PubMed

    Dixon, Timothy H; Jiang, Yan; Malservisi, Rocco; McCaffrey, Robert; Voss, Nicholas; Protti, Marino; Gonzalez, Victor

    2014-12-02

    The 5 September 2012 M(w) 7.6 earthquake on the Costa Rica subduction plate boundary followed a 62-y interseismic period. High-precision GPS recorded numerous slow slip events (SSEs) in the decade leading up to the earthquake, both up-dip and down-dip of seismic rupture. Deeper SSEs were larger than shallower ones and, if characteristic of the interseismic period, release most locking down-dip of the earthquake, limiting down-dip rupture and earthquake magnitude. Shallower SSEs were smaller, accounting for some but not all interseismic locking. One SSE occurred several months before the earthquake, but changes in Mohr-Coulomb failure stress were probably too small to trigger the earthquake. Because many SSEs have occurred without subsequent rupture, their individual predictive value is limited, but taken together they released a significant amount of accumulated interseismic strain before the earthquake, effectively defining the area of subsequent seismic rupture (rupture did not occur where slow slip was common). Because earthquake magnitude depends on rupture area, this has important implications for earthquake hazard assessment. Specifically, if this behavior is representative of future earthquake cycles and other subduction zones, it implies that monitoring SSEs, including shallow up-dip events that lie offshore, could lead to accurate forecasts of earthquake magnitude and tsunami potential.

  11. Understanding earthquake hazards in urban areas - Evansville Area Earthquake Hazards Mapping Project

    USGS Publications Warehouse

    Boyd, Oliver S.

    2012-01-01

    The region surrounding Evansville, Indiana, has experienced minor damage from earthquakes several times in the past 200 years. Because of this history and the proximity of Evansville to the Wabash Valley and New Madrid seismic zones, there is concern among nearby communities about hazards from earthquakes. Earthquakes currently cannot be predicted, but scientists can estimate how strongly the ground is likely to shake as a result of an earthquake and are able to design structures to withstand this estimated ground shaking. Earthquake-hazard maps provide one way of conveying such information and can help the region of Evansville prepare for future earthquakes and reduce earthquake-caused loss of life and financial and structural loss. The Evansville Area Earthquake Hazards Mapping Project (EAEHMP) has produced three types of hazard maps for the Evansville area: (1) probabilistic seismic-hazard maps show the ground motion that is expected to be exceeded with a given probability within a given period of time; (2) scenario ground-shaking maps show the expected shaking from two specific scenario earthquakes; (3) liquefaction-potential maps show how likely the strong ground shaking from the scenario earthquakes is to produce liquefaction. These maps complement the U.S. Geological Survey's National Seismic Hazard Maps but are more detailed regionally and take into account surficial geology, soil thickness, and soil stiffness; these elements greatly affect ground shaking.

  12. Sedimentary Environment Changes between Tsunami Events in the Central Fukushima Prefecture, Japan

    NASA Astrophysics Data System (ADS)

    Kusumoto, S.; Goto, T.; Satake, K.; Sugai, T.; Yoneda, M.; Omori, T.; Ozaki, H.

    2016-12-01

    Many tsunami deposits were found in the Tohoku region, Japan from recent and past tsunamis. Study of tsunami deposits is particularly important in the central to southern Fukushima Prefecture, which is the southern limit of the distributions of tsunami deposits of the 869 Jogan, 1454 Kyotoku and 1611 Keicho-Sanriku earthquakes. Previous studies reported that there were at least five tsunami deposits (EV1-EV5) consisted of fine-middle sand and the sedimentary environment was inner-bay or lagoon for the past 2,600 years (Goto and Aoyama, 2005; JpGU, Oikawa et al., 2011; JpGU, Oota and Hoyanagi, 2014; GSJ, Kusumoto et al., 2016; JpGU). However, the sedimentary environment changes between or across historical tsunamis have not been examined. In this study, we try to estimate the sedimentary environment changes using Total Organic Carbon (TOC), Total Nitrogen (TN) concentrations and organic Carbon-to-Nitrogen (C/N) ratio. We took 13 geological core samples of length 2.0-2.5 m at 11 locations 0.6-2.7 km from the coast. The deposits consisted of silt and massive sand with graded beddings, laminas and rip-up clasts. For samples, we performed grain-size analysis, radiocarbon age measurement and CN elemental analysis. We found three interesting characteristics. First, grain size of ordinary deposits between EV4 and EV5 tend to fine upward slightly. It suggests that tidal current became gradually weak. Second, C/N ratio is about 5-10 at every depth, meaning that organic material source was phytoplankton or zooplankton (Müller, 1977; GCA). Finally, TOC and TN concentrations slowly increase between EV4 and EV5, and they rapidly decrease across EV3 and EV4. Their slow increases correspond to sedimentary environment change from anaerobic to aerobic, whereas rapid decreases correspond to sedimentary environment change from aerobic to anaerobic. These characteristics might indicate development of sand bar between tsunami events and sudden collapse of sand bar by historical

  13. Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake

    USGS Publications Warehouse

    Hayes, Gavin P.; Herman, Matthew W.; Barnhart, William D.; Furlong, Kevin P.; Riquelme, Sebástian; Benz, Harley M.; Bergman, Eric; Barrientos, Sergio; Earle, Paul S.; Samsonov, Sergey

    2014-01-01

    The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile which had not ruptured in a megathrust earthquake since a M ~8.8 event in 1877. On 1 April 2014 a M 8.2 earthquake occurred within this seismic gap. Here we present an assessment of the seismotectonics of the March–April 2014 Iquique sequence, including analyses of earthquake relocations, moment tensors, finite fault models, moment deficit calculations and cumulative Coulomb stress transfer. This ensemble of information allows us to place the sequence within the context of regional seismicity and to identify areas of remaining and/or elevated hazard. Our results constrain the size and spatial extent of rupture, and indicate that this was not the earthquake that had been anticipated. Significant sections of the northern Chile subduction zone have not ruptured in almost 150 years, so it is likely that future megathrust earthquakes will occur to the south and potentially to the north of the 2014 Iquique sequence.

  14. Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake.

    PubMed

    Hayes, Gavin P; Herman, Matthew W; Barnhart, William D; Furlong, Kevin P; Riquelme, Sebástian; Benz, Harley M; Bergman, Eric; Barrientos, Sergio; Earle, Paul S; Samsonov, Sergey

    2014-08-21

    The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile, which had not ruptured in a megathrust earthquake since a M ∼8.8 event in 1877. On 1 April 2014 a M 8.2 earthquake occurred within this seismic gap. Here we present an assessment of the seismotectonics of the March-April 2014 Iquique sequence, including analyses of earthquake relocations, moment tensors, finite fault models, moment deficit calculations and cumulative Coulomb stress transfer. This ensemble of information allows us to place the sequence within the context of regional seismicity and to identify areas of remaining and/or elevated hazard. Our results constrain the size and spatial extent of rupture, and indicate that this was not the earthquake that had been anticipated. Significant sections of the northern Chile subduction zone have not ruptured in almost 150 years, so it is likely that future megathrust earthquakes will occur to the south and potentially to the north of the 2014 Iquique sequence.

  15. Earthquakes: Predicting the unpredictable?

    USGS Publications Warehouse

    Hough, Susan E.

    2005-01-01

    The earthquake prediction pendulum has swung from optimism in the 1970s to rather extreme pessimism in the 1990s. Earlier work revealed evidence of possible earthquake precursors: physical changes in the planet that signal that a large earthquake is on the way. Some respected earthquake scientists argued that earthquakes are likewise fundamentally unpredictable. The fate of the Parkfield prediction experiment appeared to support their arguments: A moderate earthquake had been predicted along a specified segment of the central San Andreas fault within five years of 1988, but had failed to materialize on schedule. At some point, however, the pendulum began to swing back. Reputable scientists began using the "P-word" in not only polite company, but also at meetings and even in print. If the optimism regarding earthquake prediction can be attributed to any single cause, it might be scientists' burgeoning understanding of the earthquake cycle.

  16. Comparison of two large earthquakes: the 2008 Sichuan Earthquake and the 2011 East Japan Earthquake.

    PubMed

    Otani, Yuki; Ando, Takayuki; Atobe, Kaori; Haiden, Akina; Kao, Sheng-Yuan; Saito, Kohei; Shimanuki, Marie; Yoshimoto, Norifumi; Fukunaga, Koichi

    2012-01-01

    Between August 15th and 19th, 2011, eight 5th-year medical students from the Keio University School of Medicine had the opportunity to visit the Peking University School of Medicine and hold a discussion session titled "What is the most effective way to educate people for survival in an acute disaster situation (before the mental health care stage)?" During the session, we discussed the following six points: basic information regarding the Sichuan Earthquake and the East Japan Earthquake, differences in preparedness for earthquakes, government actions, acceptance of medical rescue teams, earthquake-induced secondary effects, and media restrictions. Although comparison of the two earthquakes was not simple, we concluded that three major points should be emphasized to facilitate the most effective course of disaster planning and action. First, all relevant agencies should formulate emergency plans and should supply information regarding the emergency to the general public and health professionals on a normal basis. Second, each citizen should be educated and trained in how to minimize the risks from earthquake-induced secondary effects. Finally, the central government should establish a single headquarters responsible for command, control, and coordination during a natural disaster emergency and should centralize all powers in this single authority. We hope this discussion may be of some use in future natural disasters in China, Japan, and worldwide.

  17. [Structure and characteristics of technical support that psychiatric social workers of prefectural governments provide for municipalities].

    PubMed

    Okada, Takashi

    2017-01-01

    Objectives The support to municipalities by prefectural governments has become necessary in the fields of mental health and welfare. Therefore, psychiatric social workers (PSW) ordered from the prefectural governor has been providing technical support (TS) that promote community activities of the municipality and improve staff support for persons with mental disabilities. The purpose of this study was to identify empirical structure and characteristics of TS that PSW provide for municipality staff.Method Semi-structured interviews were conducted with seven certified PSW randomly selected from the membership list of the National Psychiatric Social Worker Organization. Inclusion criteria required participants to have more than 10 years of experience at the prefectural government and experience providing TS in the last five years. Interviews focused on two situations: a casework and a project related to mental health. Interview data were analyzed using a qualitative content method, setting a framework for the consultation process.Results The analysis included five categories < > and 15 subcategories [ ], which consisted of 37 concepts. In category with municipalities consisted of [complementary relationship] and [partnership]. The category included two subcategories, [analyze/judgment from the conditions spread in front of] and [analyze/judgment be the accumulated skills and knowledge in person]. In category , six policies were considered as important, including [problem solving and promoting action], [fostering person centered care perspective], [promoting the understanding of residents], [provide psychological support to the staff], [clarify responsibility as the municipal officials], and [coordinate to improve the environment]. Category consisted of both [support indirectly] and [support cooperatively]. The last category

  18. Assessment of an alternative housing reconstruction policy after the 1995 Grevena-Kozani (N.Greece) earthquake: Construction of standardized units in private lots

    NASA Astrophysics Data System (ADS)

    Mousteraki, K.; Dandoulaki, M.; Symeonidis, S.

    2009-04-01

    In Greece, the reconstruction of earthquake damaged building stock is technically and financially supported by the state. Housing reconstruction typically comprises three subsequent phases that is emergency shelter, temporary housing and permanent housing in buildings after their reconstruction. The latter is based on financial support by the state to the owner for the repair or reconstruction of each individual building. A different approach was tried after the 1995 Kozani-Grevena (N.Greece) earthquake. The earthquake (M=6.6) affected mainly the countryside of the two prefectures and devastated a great number of small settlements with aged and decreasing population. The experience from the 1986 Kalamata earthquake had demonstrated that low income and elderly households had difficulties in using reconstruction loans and tented to remain longer in temporary housing. In an attempt to take in the Kalamata experience and the development features of the disaster area, certain categories of homeless households were offered the choice to select either the typical financial and technical support to reconstruct their damaged house under their own responsibility or a small standard house (50 to 60m2) constructed by the state in their lot. About 4,000 housing units were constructed in villages all over the disaster area. The paper focuses on this new housing policy. It presents the institutional framework, the procedures for the selection of eligible households, the geography of the constructed housing units, issues of project management and involved costs. It also attempts to highlight strong and weak points of the new approach and to make some comparisons with the long-established approach to recovery of damaged building stock. The overall conclusion is that despite huge complexities in project management and higher costs, this new policy contributed in retaining the population and enhancing development in the area.

  19. Assessing cost and effectiveness of radiation decontamination in Fukushima Prefecture, Japan.

    PubMed

    Yasutaka, Tetsuo; Naito, Wataru

    2016-01-01

    Despite the enormous cost of radiation decontamination in Fukushima Prefecture, it is not clear what levels of reduction in external radiation exposure are possible in the Special Decontamination Area, the Intensive Contamination Survey Areas and the whole of Fukushima. The objective of this study was to evaluate the cost and effectiveness of radiation decontamination in Fukushima Prefecture in its entirety. Using a geographic information system, we calculated the costs of removal, storage containers, transport, and temporary and interim storage facilities as well as the reduction in air dose rate for a cumulative external exposure for 9000 1 km × 1 km mesh units incorporating 51 municipalities. The decontamination cost for the basic scenario, for which forested areas within 20 m of habitation areas were decontaminated, was JPY2.53-5.12 trillion; the resulting reduction in annual external dose was about 2500 person-Sv. The transport, storage, and administrative costs of decontamination waste and removed soil reached JPY1.55-2.12 trillion under this scenario. Although implementing decontamination of all forested areas provides some major reductions in the external radiation dose for the average inhabitant, decontamination costs could potentially exceed JPY16 trillion. These results indicate that technologies for reducing the volume of decontamination waste and removed soil should be considered to reduce storage costs and that further discussions about forest decontamination policies are needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Injection-induced earthquakes

    USGS Publications Warehouse

    Ellsworth, William L.

    2013-01-01

    Earthquakes in unusual locations have become an important topic of discussion in both North America and Europe, owing to the concern that industrial activity could cause damaging earthquakes. It has long been understood that earthquakes can be induced by impoundment of reservoirs, surface and underground mining, withdrawal of fluids and gas from the subsurface, and injection of fluids into underground formations. Injection-induced earthquakes have, in particular, become a focus of discussion as the application of hydraulic fracturing to tight shale formations is enabling the production of oil and gas from previously unproductive formations. Earthquakes can be induced as part of the process to stimulate the production from tight shale formations, or by disposal of wastewater associated with stimulation and production. Here, I review recent seismic activity that may be associated with industrial activity, with a focus on the disposal of wastewater by injection in deep wells; assess the scientific understanding of induced earthquakes; and discuss the key scientific challenges to be met for assessing this hazard.

  1. Earthquakes; January-February 1982

    USGS Publications Warehouse

    Person, W.J.

    1982-01-01

    In the United States, a number of earthquakes occurred, but only minor damage was reported. Arkansas experienced a swarm of earthquakes beginning on January 12. Canada experienced one of its strongest earthquakes in a number of years on January 9; this earthquake caused slight damage in Maine. 

  2. Results of the Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California.

    PubMed

    Lee, Ya-Ting; Turcotte, Donald L; Holliday, James R; Sachs, Michael K; Rundle, John B; Chen, Chien-Chih; Tiampo, Kristy F

    2011-10-04

    The Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California was the first competitive evaluation of forecasts of future earthquake occurrence. Participants submitted expected probabilities of occurrence of M ≥ 4.95 earthquakes in 0.1° × 0.1° cells for the period 1 January 1, 2006, to December 31, 2010. Probabilities were submitted for 7,682 cells in California and adjacent regions. During this period, 31 M ≥ 4.95 earthquakes occurred in the test region. These earthquakes occurred in 22 test cells. This seismic activity was dominated by earthquakes associated with the M = 7.2, April 4, 2010, El Mayor-Cucapah earthquake in northern Mexico. This earthquake occurred in the test region, and 16 of the other 30 earthquakes in the test region could be associated with it. Nine complete forecasts were submitted by six participants. In this paper, we present the forecasts in a way that allows the reader to evaluate which forecast is the most "successful" in terms of the locations of future earthquakes. We conclude that the RELM test was a success and suggest ways in which the results can be used to improve future forecasts.

  3. Results of the Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California

    PubMed Central

    Lee, Ya-Ting; Turcotte, Donald L.; Holliday, James R.; Sachs, Michael K.; Rundle, John B.; Chen, Chien-Chih; Tiampo, Kristy F.

    2011-01-01

    The Regional Earthquake Likelihood Models (RELM) test of earthquake forecasts in California was the first competitive evaluation of forecasts of future earthquake occurrence. Participants submitted expected probabilities of occurrence of M≥4.95 earthquakes in 0.1° × 0.1° cells for the period 1 January 1, 2006, to December 31, 2010. Probabilities were submitted for 7,682 cells in California and adjacent regions. During this period, 31 M≥4.95 earthquakes occurred in the test region. These earthquakes occurred in 22 test cells. This seismic activity was dominated by earthquakes associated with the M = 7.2, April 4, 2010, El Mayor–Cucapah earthquake in northern Mexico. This earthquake occurred in the test region, and 16 of the other 30 earthquakes in the test region could be associated with it. Nine complete forecasts were submitted by six participants. In this paper, we present the forecasts in a way that allows the reader to evaluate which forecast is the most “successful” in terms of the locations of future earthquakes. We conclude that the RELM test was a success and suggest ways in which the results can be used to improve future forecasts. PMID:21949355

  4. High-frequency ground motion amplification during the 2011 Tohoku earthquake explained by soil dilatancy

    NASA Astrophysics Data System (ADS)

    Roten, D.; Fäh, D.; Bonilla, L. F.

    2013-05-01

    Ground motions of the 2011 Tohoku earthquake recorded at Onahama port (Iwaki, Fukushima prefecture) rank among the highest accelerations ever observed, with the peak amplitude of the 3-D acceleration vector approaching 2g. The response of the site was distinctively non-linear, as indicated by the presence of horizontal acceleration spikes which have been linked to cyclic mobility during similar observations. Compared to records of weak ground motions, the response of the site during the Mw 9.1 earthquake was characterized by increased amplification at frequencies above 10 Hz and in peak ground acceleration. This behaviour contrasts with the more common non-linear response encountered at non-liquefiable sites, which results in deamplification at higher frequencies. We simulate propagation of SH waves through the dense sand deposit using a non-linear finite difference code that is capable of modelling the development of excess pore water pressure. Dynamic soil parameters are calibrated using a direct search method that minimizes the difference between observed and simulated acceleration envelopes and response spectra. The finite difference simulations yield surface acceleration time-series that are consistent with the observations in shape and amplitude, pointing towards soil dilatancy as a likely explanation for the high-frequency pulses recorded at Onahama port. The simulations also suggest that the occurrence of high-frequency spikes coincided with a rapid increase in pore water pressure in the upper part of the sand deposit between 145 and 170 s. This sudden increase is possibly linked to a burst of high-frequency energy from a large slip patch below the Iwaki region.

  5. The great East Japan earthquake of March 11, 2011, from the vantage point of blood banking and transfusion medicine.

    PubMed

    Nollet, Kenneth E; Ohto, Hitoshi; Yasuda, Hiroyasu; Hasegawa, Arifumi

    2013-01-01

    The Great East Japan Earthquake of March 11, 2011, and subsequent tsunami took nearly 20 000 lives in Tohoku, the northeastern part of Japan's main island. Most victims were either carried away by the tsunami or drowned. The ability to collect blood was disrupted on the Pacific coast of Tohoku. Inland areas were less affected, but allogeneic blood collected in Tohoku is tested at the Miyagi Red Cross Blood Center (Miyagi Center) in the coastal city of Sendai. Miyagi Center was damaged and could not test for 2 months. The aims of this study are as follows: (1) to assess transfusion practice at 8 disaster response hospitals in Tohoku's Fukushima Prefecture, for equal intervals before and after March 11, 2011; (2) to report activities related to blood collection and distribution in response to the disaster; and (3) to describe the Great East Japan Earthquake in the context of other disasters. Data were collected through a survey of transfusion services at 8 major disaster response hospitals, communication at transfusion conferences, and literature review. Transfused patients and units transfused were about 70% and 60% of normal in the surveyed hospitals because this was a disaster of mass casualty rather than mass injury, and patients requiring chronic care were evacuated out. A nationally coordinated effort allowed excess blood collected outside Tohoku to be transported in, despite infrastructure damage. Japan's national system of blood collection and distribution responded effectively to local needs after the Great East Japan Earthquake. Disasters such as Japan's 3.11 should guide discourse about emergency preparedness and centralization of services. Copyright © 2013. Published by Elsevier Inc.

  6. Earthquakes, September-October 1986

    USGS Publications Warehouse

    Person, W.J.

    1987-01-01

    There was one great earthquake (8.0 and above) during this reporting period in the South Pacific in the Kermadec Islands. There were no major earthquakes (7.0-7.9) but earthquake-related deaths were reported in Greece and in El Salvador. There were no destrcutive earthquakes in the United States.

  7. Annual variation in the atmospheric radon concentration in Japan.

    PubMed

    Kobayashi, Yuka; Yasuoka, Yumi; Omori, Yasutaka; Nagahama, Hiroyuki; Sanada, Tetsuya; Muto, Jun; Suzuki, Toshiyuki; Homma, Yoshimi; Ihara, Hayato; Kubota, Kazuhito; Mukai, Takahiro

    2015-08-01

    Anomalous atmospheric variations in radon related to earthquakes have been observed in hourly exhaust-monitoring data from radioisotope institutes in Japan. The extraction of seismic anomalous radon variations would be greatly aided by understanding the normal pattern of variation in radon concentrations. Using atmospheric daily minimum radon concentration data from five sampling sites, we show that a sinusoidal regression curve can be fitted to the data. In addition, we identify areas where the atmospheric radon variation is significantly affected by the variation in atmospheric turbulence and the onshore-offshore pattern of Asian monsoons. Furthermore, by comparing the sinusoidal regression curve for the normal annual (seasonal) variations at the five sites to the sinusoidal regression curve for a previously published dataset of radon values at the five Japanese prefectures, we can estimate the normal annual variation pattern. By fitting sinusoidal regression curves to the previously published dataset containing sites in all Japanese prefectures, we find that 72% of the Japanese prefectures satisfy the requirements of the sinusoidal regression curve pattern. Using the normal annual variation pattern of atmospheric daily minimum radon concentration data, these prefectures are suitable areas for obtaining anomalous radon variations related to earthquakes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Post earthquake recovery in natural gas systems--1971 San Fernando Earthquake

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Johnson, W.T. Jr.

    1983-01-01

    In this paper a concise summary of the post earthquake investigations for the 1971 San Fernando Earthquake is presented. The effects of the earthquake upon building and other above ground structures are briefly discussed. Then the damages and subsequent repairs in the natural gas systems are reported.

  9. Healthcare IT system in the midst of and after Great East Japan Earthquake Disaster : Grand design for reconstruction of Tohoku-region healthcare IT system

    NASA Astrophysics Data System (ADS)

    Tanaka, Hiroshi

    In this article, we described what was really going in the disaster medical care at the Great East Japan Earthquake, mainly in Ishinomaki and Kesen-numa areas. As for exchange tools of the disaster information, in contrast to the breakdown of fixed-line and mobile phone, MCA radio system, satellite mobiles and internet, especially SNS, were greatly helpful. Learned from the disaster experiences, we are making the grand design for “disaster-robust” regional healthcare IT systems, which are composed of (1) cloud center storing whole-prefecture medical records, (2) SS-MIX based regional healthcare information systems of “the second medical care zones”, (3) ASP/SaaS typed electronic medical record system for all clinics located at Pacific coastal areas, and (4) wireless communication environment supporting comprehensive care of elderly for daily living activities.

  10. Earthquakes; July-August, 1978

    USGS Publications Warehouse

    Person, W.J.

    1979-01-01

    Earthquake activity during this period was about normal. Deaths from earthquakes were reported from Greece and Guatemala. Three major earthquakes (magnitude 7.0-7.9) occurred in Taiwan, Chile, and Costa Rica. In the United States, the most significant earthquake was a magnitude 5.6 on August 13 in southern California. 

  11. Improvements of the offshore earthquake locations in the Earthquake Early Warning System

    NASA Astrophysics Data System (ADS)

    Chen, Ta-Yi; Hsu, Hsin-Chih

    2017-04-01

    Since 2014 the Earthworm Based Earthquake Alarm Reporting (eBEAR) system has been operated and been used to issue warnings to schools. In 2015 the system started to provide warnings to the public in Taiwan via television and the cell phone. Online performance of the eBEAR system indicated that the average reporting times afforded by the system are approximately 15 and 28 s for inland and offshore earthquakes, respectively. The eBEAR system in average can provide more warning time than the current EEW system (3.2 s and 5.5 s for inland and offshore earthquakes, respectively). However, offshore earthquakes were usually located poorly because only P-wave arrivals were used in the eBEAR system. Additionally, in the early stage of the earthquake early warning system, only fewer stations are available. The poor station coverage may be a reason to answer why offshore earthquakes are difficult to locate accurately. In the Geiger's inversion procedure of earthquake location, we need to put an initial hypocenter and origin time into the location program. For the initial hypocenter, we defined some test locations on the offshore area instead of using the average of locations from triggered stations. We performed 20 programs concurrently running the Geiger's method with different pre-defined initial position to locate earthquakes. We assume that if the program with the pre-defined initial position is close to the true earthquake location, during the iteration procedure of the Geiger's method the processing time of this program should be less than others. The results show that using pre-defined locations for trial-hypocenter in the inversion procedure is able to improve the accurate of offshore earthquakes. Especially for EEW system, in the initial stage of the EEW system, only use 3 or 5 stations to locate earthquakes may lead to bad results because of poor station coverage. In this study, the pre-defined trial-locations provide a feasible way to improve the estimations of

  12. Megathrust earthquakes in Central Chile: What is next after the Maule 2010 earthquake?

    NASA Astrophysics Data System (ADS)

    Madariaga, R.

    2013-05-01

    The 27 February 2010 Maule earthquake occurred in a well identified gap in the Chilean subduction zone. The event has now been studied in detail using both far-field, near field seismic and geodetic data, we will review this information gathered so far. The event broke a region that was much longer along strike than the gap left over from the 1835 Concepcion earthquake, sometimes called the Darwin earthquake because he was in the area when the earthquake occurred and made many observations. Recent studies of contemporary documents by Udias et al indicate that the area broken by the Maule earthquake in 2010 had previously broken by a similar earthquake in 1751, but several events in the magnitude 8 range occurred in the area principally in 1835 already mentioned and, more recently on 1 December 1928 to the North and on 21 May 1960 (1 1/2 days before the big Chilean earthquake of 1960). Currently the area of the 2010 earthquake and the region immediately to the North is undergoing a very large increase in seismicity with numerous clusters of seismicity that move along the plate interface. Examination of the seismicity of Chile of the 18th and 19th century show that the region immediately to the North of the 2010 earthquake broke in a very large megathrust event in July 1730. this is the largest known earthquake in central Chile. The region where this event occurred has broken in many occasions with M 8 range earthquakes in 1822, 1880, 1906, 1971 and 1985. Is it preparing for a new very large megathrust event? The 1906 earthquake of Mw 8.3 filled the central part of the gap but it has broken again on several occasions in 1971, 1973 and 1985. The main question is whether the 1906 earthquake relieved enough stresses from the 1730 rupture zone. Geodetic data shows that most of the region that broke in 1730 is currently almost fully locked from the northern end of the Maule earthquake at 34.5°S to 30°S, near the southern end of the of the Mw 8.5 Atacama earthquake of 11

  13. Inspections of radiocesium concentration levels in rice from Fukushima Prefecture after the Fukushima Dai-ichi Nuclear Power Plant accident

    PubMed Central

    Nihei, Naoto; Tanoi, Keitaro; Nakanishi, Tomoko M.

    2015-01-01

    We summarize the inspections of radiocesium concentration levels in rice produced in Fukushima Prefecture, Japan, for 3 years from the nuclear accident in 2011. In 2011, three types of verifications, preliminary survey, main inspection, and emergency survey, revealed that rice with radiocesium concentration levels over 500 Bq/kg (the provisional regulation level until March 2012 in Japan) was identified in the areas north and west of the Fukushima nuclear power plant. The internal exposure of an average adult eating rice grown in the area north of the nuclear plant was estimated as 0.05 mSv/year. In 2012, Fukushima Prefecture authorities decided to investigate the radiocesium concentration levels in all rice using custom-made belt conveyor testers. Notably, rice with radiocesium concentration levels over 100 Bq/kg (the new standard since April 2012 in Japan) were detected in only 71 and 28 bags out of the total 10,338,000 in 2012 and 11,001,000 in 2013, respectively. We considered that there were almost no rice exceeding 100 Bq/kg produced in Fukushima Prefecture after 3 years from the nuclear accident, and the safety of Fukushima's rice were ensured because of the investigation of all rice. PMID:25731663

  14. Modelling evolution of air dose rates in river basins in Fukushima Prefecture affected by sediment-sorbed radiocesium redistribution

    NASA Astrophysics Data System (ADS)

    Malins, A.; Sakuma, K.; Nakanishi, T.; Kurikami, H.; Machida, M.; Kitamura, A.; Yamada, S.

    2015-12-01

    The radioactive 134Cs and 137Cs isotopes deposited over Fukushima Prefecture by the Fukushima Daiichi nuclear disaster are the predominant radiological concern for the years following the accident. This is because the energetic gamma radiation they emit on decay constitutes the majority of the elevated air dose rates that now afflict the region. Therefore, we developed a tool for calculating air dose rates from arbitrary radiocesium spatial distributions across the land surface and depth profiles within the ground. As cesium is strongly absorbed by clay soils, its primary redistribution mechanism within Fukushima Prefecture is by soil erosion and water-borne sediment transport. Each year between 0.1~1% of the total radiocesium inventory in the river basins neighboring Fukushima Daiichi is eroded from the land surface and enters into water courses, predominantly during typhoon storms. Although this is a small amount in relative terms, in absolute terms it corresponds to terabecquerels of 134Cs and 137Cs redistribution each year and this can affect the air dose rate at locations of high erosion and sediment deposition. This study inputs the results of sediment redistribution simulations into the dose rate evaluation tool to calculate the locations and magnitude of air dose rate changes due to radiocesium redistribution. The dose rate calculations are supported by handheld survey instrument results taken within the Prefecture.

  15. Earthquakes; March-April 1975

    USGS Publications Warehouse

    Person, W.J.

    1975-01-01

    There were no major earthquakes (magnitude 7.0-7.9) in March or April; however, there were earthquake fatalities in Chile, Iran, and Venezuela and approximately 35 earthquake-related injuries were reported around the world. In the United States a magnitude 6.0 earthquake struck the Idaho-Utah border region. Damage was estimated at about a million dollars. The shock was felt over a wide area and was the largest to hit the continental Untied States since the San Fernando earthquake of February 1971. 

  16. Protecting your family from earthquakes: The seven steps to earthquake safety

    USGS Publications Warehouse

    Developed by American Red Cross, Asian Pacific Fund

    2007-01-01

    This book is provided here because of the importance of preparing for earthquakes before they happen. Experts say it is very likely there will be a damaging San Francisco Bay Area earthquake in the next 30 years and that it will strike without warning. It may be hard to find the supplies and services we need after this earthquake. For example, hospitals may have more patients than they can treat, and grocery stores may be closed for weeks. You will need to provide for your family until help arrives. To keep our loved ones and our community safe, we must prepare now. Some of us come from places where earthquakes are also common. However, the dangers of earthquakes in our homelands may be very different than in the Bay Area. For example, many people in Asian countries die in major earthquakes when buildings collapse or from big sea waves called tsunami. In the Bay Area, the main danger is from objects inside buildings falling on people. Take action now to make sure your family will be safe in an earthquake. The first step is to read this book carefully and follow its advice. By making your home safer, you help make our community safer. Preparing for earthquakes is important, and together we can make sure our families and community are ready. English version p. 3-13 Chinese version p. 14-24 Vietnamese version p. 25-36 Korean version p. 37-48

  17. [Unprotected sexual intercourse and its correlates within HIV serodiscordant couples in Dehong prefecture of Yunnan Province, China, in 2014].

    PubMed

    Zhang, Y C; Cao, Y F; Yang, Y C; Tang, R H; Yang, S J; Li, L; Yao, S T; Ye, R H; Wang, J B; Duan, S; He, N

    2017-01-06

    Objective: To study the prevalence and correlates of unprotected sexual intercourse within HIV serodiscordant couples in Dehong prefecture, Yunnan Province, China, in 2014. Methods: This study was based on the follow-up investigation of "the AIDS cohort of seronegative spouses of HIV-infected individuals in Dehong prefecture" in 2014. The 1 520 participants were HIV seronegative spouses from all five counties/cities of Dehong prefecture who voluntarily participated in the cohort. Inclusion criteria included: having a HIV-positive spouse; ≥16 years of age; having had sexual intercourse with spouse in the past year; and being a resident of Dehong prefecture. Information on HIV-positive spouses were also collected through the local AIDS epidemic database. Chi square analysis was performed to compare differences in the rates of unprotected sexual intercourse between participants with different characteristics and lifestyle choices. Multivariable logistic regression model analysis was performed to determine correlates with unprotected sexual intercourse. Results: The 1 520 participants had a mean age of 38.7±9.4, compared with 39.7±8.9 for their HIV-positive spouses. Among the HIV-positive spouses, 77.8% (1 183/1 520) had been infected for more than 3 years, and 87.6% (1 332/1 520) had received antiretroviral therapy. The prevalence of unprotected sexual intercourse within serodiscordant couples over the past 12 months was 16.1% (244/1 520). The prevalence of unprotected sexual intercourse correlated with the level of education of HIV-negative spouses (illiterate vs . middle school and above, OR= 1.58, P= 0.044), the number of years since diagnosis of HIV-positive spouses (short vs . long, OR= 1.6, P= 0.006), antiretroviral therapy of HIV-positive spouses (no vs . yes, OR= 2.78, P <0.001), the frequency of sexual intercourse per month (high vs . low, OR= 1.66, P= 0.019), and whether the couple had children (no vs . yes, OR= 1.72, P= 0.007). Conclusion: The

  18. Earthquake Triggering in the September 2017 Mexican Earthquake Sequence

    NASA Astrophysics Data System (ADS)

    Fielding, E. J.; Gombert, B.; Duputel, Z.; Huang, M. H.; Liang, C.; Bekaert, D. P.; Moore, A. W.; Liu, Z.; Ampuero, J. P.

    2017-12-01

    Southern Mexico was struck by four earthquakes with Mw > 6 and numerous smaller earthquakes in September 2017, starting with the 8 September Mw 8.2 Tehuantepec earthquake beneath the Gulf of Tehuantepec offshore Chiapas and Oaxaca. We study whether this M8.2 earthquake triggered the three subsequent large M>6 quakes in southern Mexico to improve understanding of earthquake interactions and time-dependent risk. All four large earthquakes were extensional despite the the subduction of the Cocos plate. The traditional definition of aftershocks: likely an aftershock if it occurs within two rupture lengths of the main shock soon afterwards. Two Mw 6.1 earthquakes, one half an hour after the M8.2 beneath the Tehuantepec gulf and one on 23 September near Ixtepec in Oaxaca, both fit as traditional aftershocks, within 200 km of the main rupture. The 19 September Mw 7.1 Puebla earthquake was 600 km away from the M8.2 shock, outside the standard aftershock zone. Geodetic measurements from interferometric analysis of synthetic aperture radar (InSAR) and time-series analysis of GPS station data constrain finite fault total slip models for the M8.2, M7.1, and M6.1 Ixtepec earthquakes. The early M6.1 aftershock was too close in time and space to the M8.2 to measure with InSAR or GPS. We analyzed InSAR data from Copernicus Sentinel-1A and -1B satellites and JAXA ALOS-2 satellite. Our preliminary geodetic slip model for the M8.2 quake shows significant slip extended > 150 km NW from the hypocenter, longer than slip in the v1 finite-fault model (FFM) from teleseismic waveforms posted by G. Hayes at USGS NEIC. Our slip model for the M7.1 earthquake is similar to the v2 NEIC FFM. Interferograms for the M6.1 Ixtepec quake confirm the shallow depth in the upper-plate crust and show centroid is about 30 km SW of the NEIC epicenter, a significant NEIC location bias, but consistent with cluster relocations (E. Bergman, pers. comm.) and with Mexican SSN location. Coulomb static stress

  19. Earthquake catalog for estimation of maximum earthquake magnitude, Central and Eastern United States: Part A, Prehistoric earthquakes

    USGS Publications Warehouse

    Wheeler, Russell L.

    2014-01-01

    Computation of probabilistic earthquake hazard requires an estimate of Mmax, the maximum earthquake magnitude thought to be possible within a specified geographic region. This report is Part A of an Open-File Report that describes the construction of a global catalog of moderate to large earthquakes, from which one can estimate Mmax for most of the Central and Eastern United States and adjacent Canada. The catalog and Mmax estimates derived from it were used in the 2014 edition of the U.S. Geological Survey national seismic-hazard maps. This Part A discusses prehistoric earthquakes that occurred in eastern North America, northwestern Europe, and Australia, whereas a separate Part B deals with historical events.

  20. The initial subevent of the 1994 Northridge, California, earthquake: Is earthquake size predictable?

    USGS Publications Warehouse

    Kilb, Debi; Gomberg, J.

    1999-01-01

    We examine the initial subevent (ISE) of the M?? 6.7, 1994 Northridge, California, earthquake in order to discriminate between two end-member rupture initiation models: the 'preslip' and 'cascade' models. Final earthquake size may be predictable from an ISE's seismic signature in the preslip model but not in the cascade model. In the cascade model ISEs are simply small earthquakes that can be described as purely dynamic ruptures. In this model a large earthquake is triggered by smaller earthquakes; there is no size scaling between triggering and triggered events and a variety of stress transfer mechanisms are possible. Alternatively, in the preslip model, a large earthquake nucleates as an aseismically slipping patch in which the patch dimension grows and scales with the earthquake's ultimate size; the byproduct of this loading process is the ISE. In this model, the duration of the ISE signal scales with the ultimate size of the earthquake, suggesting that nucleation and earthquake size are determined by a more predictable, measurable, and organized process. To distinguish between these two end-member models we use short period seismograms recorded by the Southern California Seismic Network. We address questions regarding the similarity in hypocenter locations and focal mechanisms of the ISE and the mainshock. We also compare the ISE's waveform characteristics to those of small earthquakes and to the beginnings of earthquakes with a range of magnitudes. We find that the focal mechanisms of the ISE and mainshock are indistinguishable, and both events may have nucleated on and ruptured the same fault plane. These results satisfy the requirements for both models and thus do not discriminate between them. However, further tests show the ISE's waveform characteristics are similar to those of typical small earthquakes in the vicinity and more importantly, do not scale with the mainshock magnitude. These results are more consistent with the cascade model.

  1. Mines and mineral processing facilities in the vicinity of the March 11, 2011, earthquake in northern Honshu, Japan

    USGS Publications Warehouse

    Menzie, W. David; Baker, Michael S.; Bleiwas, Donald I.; Kuo, Chin

    2011-01-01

    U.S. Geological Survey data indicate that the area affected by the March 11, 2011, magnitude 9.0 earthquake and associated tsunami is home to nine cement plants, eight iodine plants, four iron and steel plants, four limestone mines, three copper refineries, two gold refineries, two lead refineries, two zinc refineries, one titanium dioxide plant, and one titanium sponge processing facility. These facilities have the capacity to produce the following percentages of the world's nonfuel mineral production: 25 percent of iodine, 10 percent of titanium sponge (metal), 3 percent of refined zinc, 2.5 percent of refined copper, and 1.4 percent of steel. In addition, the nine cement plants contribute about one-third of Japan's cement annual production. The iodine is a byproduct from production of natural gas at the Miniami Kanto gas field, east of Tokyo in Chiba Prefecture. Japan is the world's second leading (after Chile) producer of iodine, which is processed in seven nearby facilities.

  2. Identification of Deep Earthquakes

    DTIC Science & Technology

    2010-09-01

    discriminants that will reliably separate small, crustal earthquakes (magnitudes less than about 4 and depths less than about 40 to 50 km) from small...characteristics on discrimination plots designed to separate nuclear explosions from crustal earthquakes. Thus, reliably flagging these small, deep events is...Further, reliably identifying subcrustal earthquakes will allow us to eliminate deep events (previously misidentified as crustal earthquakes) from

  3. The 1985 central chile earthquake: a repeat of previous great earthquakes in the region?

    PubMed

    Comte, D; Eisenberg, A; Lorca, E; Pardo, M; Ponce, L; Saragoni, R; Singh, S K; Suárez, G

    1986-07-25

    A great earthquake (surface-wave magnitude, 7.8) occurred along the coast of central Chile on 3 March 1985, causing heavy damage to coastal towns. Intense foreshock activity near the epicenter of the main shock occurred for 11 days before the earthquake. The aftershocks of the 1985 earthquake define a rupture area of 170 by 110 square kilometers. The earthquake was forecast on the basis of the nearly constant repeat time (83 +/- 9 years) of great earthquakes in this region. An analysis of previous earthquakes suggests that the rupture lengths of great shocks in the region vary by a factor of about 3. The nearly constant repeat time and variable rupture lengths cannot be reconciled with time- or slip-predictable models of earthquake recurrence. The great earthquakes in the region seem to involve a variable rupture mode and yet, for unknown reasons, remain periodic. Historical data suggest that the region south of the 1985 rupture zone should now be considered a gap of high seismic potential that may rupture in a great earthquake in the next few tens of years.

  4. Impact of the 11 March, 2011, Tohoku earthquake and tsunami on the chemical industry

    NASA Astrophysics Data System (ADS)

    Krausmann, E.; Cruz, A. M.

    2012-04-01

    An earthquake of magnitude 9.0 occurred off the Pacific coast of Tohoku, Japan, on March 11, 2011, at 14:46:23 Japan Standard Time (5:46:23 UTC). It generated a tsunami 130 km off the coast of Miyagi Prefecture in northeast Japan, which inundated over 400 km2 of land. The death toll has reached >15,800 according to the Japan National Policy Agency with over 3,700 still missing as of 26 October 2011. Significant damage to or complete collapse of houses also resulted. The earthquake generated strong ground motion; nevertheless most damage was caused by the tsunami, which is a tribute to the effectiveness of Japan's earthquake damage reduction measures in saving lives and property. Nonetheless, the direct losses amount to more than 200 billion US dollars (not counting the costs of the accident at the Fukushima nuclear power plant). The earthquake and tsunami had a significant impact on all types of industry, and in particular on the petrochemical and chemical industry in the affected areas, resulting in hazardous-materials releases, fires and explosions and forcing businesses to interrupt production. These so-called Natech accidents pose an immediate or even long-term threat to the population and the environment, and can also interrupt the supply chain. Overall, the earthquake and tsunami took over 30% of Japan's oil production offline, and two refineries are still not or only partially in operation to repair the damage caused by the fires and explosions. The fire-fighting efforts could only be started 4 days after the disaster due to the absence of personnel that had been evacuated and because of the continuing tsunami alerts. In one of the affected refineries the fires could only be extinguished 10 days after the disasters. Many petrochemical and chemical companies reported problems either due to damage to facilities or because of power outages. In fact, in facilities that suffered no or only minor damage the resuming of operations was hampered by continuous

  5. Optical Observation of LEO Debris Caused by Feng Yun 1C

    NASA Astrophysics Data System (ADS)

    Kurosaki, Hirohisa; Yanagisawa, Toshifumi; Nakajima, Atsushi

    Many pieces of space debris are in low earth orbit (LEO), and may be a serious problem in the near future. They are very hazardous to spacecraft such as the ISS, in which humans stay for long periods. In January 2007, China performed an experimental destruction of the meteorological satellite FengYun-1C in low earth orbit using a ballistic missile. Optical instruments for space debris observation were installed on Mt. Nyukasa in Nagano Prefecture by JAXA, and the resulting low earth orbit debris was observed with the small telescope there. We have developed an image-processing technique, the line-detection method, to extract such effects as the streaks created by meteors, LEO satellites, and LEO debris. We succeeded in detecting the trajectories of specified FengYun-1C debris whose TLE were known. In this paper, the detection and observation of low earth orbit debris are discussed.

  6. Aftershocks associated with impaired health caused by the great East Japan disaster among youth across Japan: a national cross-sectional survey.

    PubMed

    Sugimoto, Takashi; Shinozaki, Tomohiro; Miyamoto, Yuki

    2013-12-20

    The Great East Japan earthquake, subsequent tsunamis and the Fukushima nuclear incident had a tremendous impact on Japanese society. Although small-scale surveys have been conducted in highly affected areas, few have elucidated the disaster's effect on health from national perspective, which is necessary to prepare national policy and response. The aim of the present study was to describe prefecture-level health status and investigate associations with number of aftershocks, seismic intensity, a closer geographical location to the Fukushima Nuclear Power Plant, or higher reported radiation dose in each prefecture even after adjusting for individual socioeconomic factors, by utilizing individual-level data acquired from a national cross-sectional Internet survey as well as officially reported prefecture-level data. A Japanese government research institute obtained 12,000 participants by quota sampling and 7335 participants were eligible for the analysis in an age range between 17 and 27 years old. We calculated the percentage of people with decreased subjective health in each prefecture after the earthquake. Variability introduced by a small sample size for some prefectures was smoothed using empirical Bayes estimation with a random-intercept logistic model, with and without demographic factors. Multilevel logistic regression was used to calculate adjusted odds ratios (ORs) for change of subjective health associated with prefecture-level and individual-level factors. Adjusted empirical Bayes estimates were higher for respondents commuting in the northeast region (Iwate 14%, Miyagi 19%, and Fukushima 28%), which faces the Pacific Ocean, while the values for Akita (10%) and Yamagata (8%) prefectures, which do not face the Pacific Ocean, were lower than those of Tokyo (12%). The values from the central to the western region were clearly lower. The number of aftershocks was coherently associated with decreased health (OR 1.05 per 100 times, 95% CI 1.04-1.06; P<.001

  7. The relationship between earthquake exposure and posttraumatic stress disorder in 2013 Lushan earthquake

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Lu, Yi

    2018-01-01

    The objective of this study is to explore the relationship between earthquake exposure and the incidence of PTSD. A stratification random sample survey was conducted to collect data in the Longmenshan thrust fault after Lushan earthquake three years. We used the Children's Revised Impact of Event Scale (CRIES-13) and the Earthquake Experience Scale. Subjects in this study included 3944 school student survivors in local eleven schools. The prevalence of probable PTSD is relatively higher, when the people was trapped in the earthquake, was injured in the earthquake or have relatives who died in the earthquake. It concluded that researchers need to pay more attention to the children and adolescents. The government should pay more attention to these people and provide more economic support.

  8. Crowdsourced earthquake early warning.

    PubMed

    Minson, Sarah E; Brooks, Benjamin A; Glennie, Craig L; Murray, Jessica R; Langbein, John O; Owen, Susan E; Heaton, Thomas H; Iannucci, Robert A; Hauser, Darren L

    2015-04-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an M w (moment magnitude) 7 earthquake on California's Hayward fault, and real data from the M w 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

  9. Crowdsourced earthquake early warning

    PubMed Central

    Minson, Sarah E.; Brooks, Benjamin A.; Glennie, Craig L.; Murray, Jessica R.; Langbein, John O.; Owen, Susan E.; Heaton, Thomas H.; Iannucci, Robert A.; Hauser, Darren L.

    2015-01-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing. PMID:26601167

  10. Earthquakes, November-December 1992

    USGS Publications Warehouse

    Person, W.J.

    1993-01-01

    There were two major earthquakes (7.0≤M<8.0) during the last two months of the year, a magntidue 7.5 earthquake on December 12 in the Flores region, Indonesia, and a magnitude 7.0 earthquake on December 20 in the Banda Sea. Earthquakes caused fatalities in China and Indonesia. The greatest number of deaths (2,500) for the year occurred in Indonesia. In Switzerland, six people were killed by an accidental explosion recoreded by seismographs. In teh United States, a magnitude 5.3 earthquake caused slight damage at Big Bear in southern California. 

  11. Crowdsourced earthquake early warning

    USGS Publications Warehouse

    Minson, Sarah E.; Brooks, Benjamin A.; Glennie, Craig L.; Murray, Jessica R.; Langbein, John O.; Owen, Susan E.; Heaton, Thomas H.; Iannucci, Robert A.; Hauser, Darren L.

    2015-01-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

  12. Earthquake Clusters and Spatio-temporal Migration of earthquakes in Northeastern Tibetan Plateau: a Finite Element Modeling

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Luo, G.

    2017-12-01

    Seismicity in a region is usually characterized by earthquake clusters and earthquake migration along its major fault zones. However, we do not fully understand why and how earthquake clusters and spatio-temporal migration of earthquakes occur. The northeastern Tibetan Plateau is a good example for us to investigate these problems. In this study, we construct and use a three-dimensional viscoelastoplastic finite-element model to simulate earthquake cycles and spatio-temporal migration of earthquakes along major fault zones in northeastern Tibetan Plateau. We calculate stress evolution and fault interactions, and explore effects of topographic loading and viscosity of middle-lower crust and upper mantle on model results. Model results show that earthquakes and fault interactions increase Coulomb stress on the neighboring faults or segments, accelerating the future earthquakes in this region. Thus, earthquakes occur sequentially in a short time, leading to regional earthquake clusters. Through long-term evolution, stresses on some seismogenic faults, which are far apart, may almost simultaneously reach the critical state of fault failure, probably also leading to regional earthquake clusters and earthquake migration. Based on our model synthetic seismic catalog and paleoseismic data, we analyze probability of earthquake migration between major faults in northeastern Tibetan Plateau. We find that following the 1920 M 8.5 Haiyuan earthquake and the 1927 M 8.0 Gulang earthquake, the next big event (M≥7) in northeastern Tibetan Plateau would be most likely to occur on the Haiyuan fault.

  13. Prototype operational earthquake prediction system

    USGS Publications Warehouse

    Spall, Henry

    1986-01-01

    An objective if the U.S. Earthquake Hazards Reduction Act of 1977 is to introduce into all regions of the country that are subject to large and moderate earthquakes, systems for predicting earthquakes and assessing earthquake risk. In 1985, the USGS developed for the Secretary of the Interior a program for implementation of a prototype operational earthquake prediction system in southern California.

  14. Perception of earthquake risk in Taiwan: effects of gender and past earthquake experience.

    PubMed

    Kung, Yi-Wen; Chen, Sue-Huei

    2012-09-01

    This study explored how individuals in Taiwan perceive the risk of earthquake and the relationship of past earthquake experience and gender to risk perception. Participants (n= 1,405), including earthquake survivors and those in the general population without prior direct earthquake exposure, were selected and interviewed through a computer-assisted telephone interviewing procedure using a random sampling and stratification method covering all 24 regions of Taiwan. A factor analysis of the interview data yielded a two-factor structure of risk perception in regard to earthquake. The first factor, "personal impact," encompassed perception of threat and fear related to earthquakes. The second factor, "controllability," encompassed a sense of efficacy of self-protection in regard to earthquakes. The findings indicated prior earthquake survivors and females reported higher scores on the personal impact factor than males and those with no prior direct earthquake experience, although there were no group differences on the controllability factor. The findings support that risk perception has multiple components, and suggest that past experience (survivor status) and gender (female) affect the perception of risk. Exploration of potential contributions of other demographic factors such as age, education, and marital status to personal impact, especially for females and survivors, is discussed. Future research on and intervention program with regard to risk perception are suggested accordingly. © 2012 Society for Risk Analysis.

  15. Earthquakes in Alaska

    USGS Publications Warehouse

    Haeussler, Peter J.; Plafker, George

    1995-01-01

    Earthquake risk is high in much of the southern half of Alaska, but it is not the same everywhere. This map shows the overall geologic setting in Alaska that produces earthquakes. The Pacific plate (darker blue) is sliding northwestward past southeastern Alaska and then dives beneath the North American plate (light blue, green, and brown) in southern Alaska, the Alaska Peninsula, and the Aleutian Islands. Most earthquakes are produced where these two plates come into contact and slide past each other. Major earthquakes also occur throughout much of interior Alaska as a result of collision of a piece of crust with the southern margin.

  16. Spatial transmission of H5N6 highly pathogenic avian influenza viruses among wild birds in Ibaraki Prefecture, Japan, 2016-2017.

    PubMed

    Tsunekuni, Ryota; Yaguchi, Yuji; Kashima, Yuki; Yamashita, Kaoru; Takemae, Nobuhiro; Mine, Junki; Tanikawa, Taichiro; Uchida, Yuko; Saito, Takehiko

    2018-05-01

    From 29 November 2016 to 24 January 2017, sixty-three cases of H5N6 highly pathogenic avian influenza virus (HPAIV) infections were detected in wild birds in Ibaraki Prefecture, Japan. Here, we analyzed the genetic, temporal, and geographic correlations of these 63 HPAIVs to elucidate their dissemination throughout the prefecture. Full-genome sequence analysis of the Ibaraki isolates showed that 7 segments (PB2, PB1, PA, HA, NP, NA, NS) were derived from G1.1.9 strains while the M segment was from G1.1 strains; both groups of strains circulated in south China. Pathological studies revealed severe systemic infection in dead swans (the majority of dead birds and the only species necropsied), thus indicating high susceptibility to H5N6 HPAIVs. Coalescent phylogenetic analysis using the 7 G1.1.9-derived segments enabled detailed analysis of the short-term evolution of these highly homologous HPAIVs. This analysis revealed that the H5N6 HPAIVs isolated from wild birds in Ibaraki Prefecture were divided into 7 groups. Spatial analysis demonstrated that most of the cases concentrated around Senba Lake originated from a single source, and progeny viruses were transmitted to other locations after the infection expanded in mute swans. In contrast, within just a 5-km radius of the area in which cases were concentrated, three different intrusions of H5N6 HPAIVs were evident. Multi-segment analysis of short-term evolution showed that not only was the invading virus spread throughout Ibaraki Prefecture but also that, despite the small size of this region, multiple invasions had occurred during winter 2016-2017.

  17. Experiences of municipal public health nurses following Japan's earthquake, tsunami, and nuclear disaster.

    PubMed

    Kayama, Mami; Akiyama, Tsuyoshi; Ohashi, Akiko; Horikoshi, Naoko; Kido, Yoshifumi; Murakata, Tazuko; Kawakami, Norito

    2014-01-01

    The purpose of this study was to explore the experiences of municipal public health nurses in the wake of the March 2011 massive earthquake and tsunami and resulting nuclear accident in Fukushima, Japan, from the time of the disaster until December 2013. Thirty-two public health nurses working in three cities in Fukushima prefecture were divided into four focus groups and took part in interviews, which were analyzed using a qualitative descriptive method. Two major themes were extracted: (1) experiences of difficulties and dilemmas, and (2) professional challenges and the meaning of excellence as a public health nurse. Subjects recounted their experiences based on the timeline of events. The process of overcoming various dilemmas--between prescribed roles and actual needs on the ground, being both civil servants and private citizens with families, and having to be publicly accountable while lacking adequate information--caused participants to reexamine the meaning of excellence in the practice of public health. The strenuous and complex demands of extended disaster management caused subjects to grow professionally. Helping them process their emotions should also help these nurses give focus to their posttraumatic growth, and strengthen their sense of professionalism. © 2014 Wiley Periodicals, Inc.

  18. Earthquakes, November-December 1973

    USGS Publications Warehouse

    Person, W.J.

    1974-01-01

    Other parts of the world suffered fatalities and significant damage from earthquakes. In Iran, an earthquake killed one person, injured many, and destroyed a number of homes. Earthquake fatalities also occurred in the Azores and in Algeria. 

  19. Comparative study of earthquake-related and non-earthquake-related head traumas using multidetector computed tomography

    PubMed Central

    Chu, Zhi-gang; Yang, Zhi-gang; Dong, Zhi-hui; Chen, Tian-wu; Zhu, Zhi-yu; Shao, Heng

    2011-01-01

    OBJECTIVE: The features of earthquake-related head injuries may be different from those of injuries obtained in daily life because of differences in circumstances. We aim to compare the features of head traumas caused by the Sichuan earthquake with those of other common head traumas using multidetector computed tomography. METHODS: In total, 221 patients with earthquake-related head traumas (the earthquake group) and 221 patients with other common head traumas (the non-earthquake group) were enrolled in our study, and their computed tomographic findings were compared. We focused the differences between fractures and intracranial injuries and the relationships between extracranial and intracranial injuries. RESULTS: More earthquake-related cases had only extracranial soft tissue injuries (50.7% vs. 26.2%, RR = 1.9), and fewer cases had intracranial injuries (17.2% vs. 50.7%, RR = 0.3) compared with the non-earthquake group. For patients with fractures and intracranial injuries, there were fewer cases with craniocerebral injuries in the earthquake group (60.6% vs. 77.9%, RR = 0.8), and the earthquake-injured patients had fewer fractures and intracranial injuries overall (1.5±0.9 vs. 2.5±1.8; 1.3±0.5 vs. 2.1±1.1). Compared with the non-earthquake group, the incidences of soft tissue injuries and cranial fractures combined with intracranial injuries in the earthquake group were significantly lower (9.8% vs. 43.7%, RR = 0.2; 35.1% vs. 82.2%, RR = 0.4). CONCLUSION: As depicted with computed tomography, the severity of earthquake-related head traumas in survivors was milder, and isolated extracranial injuries were more common in earthquake-related head traumas than in non-earthquake-related injuries, which may have been the result of different injury causes, mechanisms and settings. PMID:22012045

  20. Earthquakes, May-June 1991

    USGS Publications Warehouse

    Person, W.J.

    1992-01-01

    In the United States, a magnitude 5.8 earthquake in southern California on June 28 killed two people and caused considerable damage. Strong earthquakes hit Alaska on May 1 and May 30; the May 1 earthquake caused some minor damage. 

  1. Effect of Evacuation on Body Weight After the Great East Japan Earthquake.

    PubMed

    Ohira, Tetsuya; Hosoya, Mitsuaki; Yasumura, Seiji; Satoh, Hiroaki; Suzuki, Hitoshi; Sakai, Akira; Ohtsuru, Akira; Kawasaki, Yukihiko; Takahashi, Atsushi; Ozasa, Kotaro; Kobashi, Gen; Kamiya, Kenji; Yamashita, Shunichi; Abe, Masafumi

    2016-05-01

    The Great East Japan Earthquake occurred on March 11, 2011, with a nuclear accident subsequently occurring at the Fukushima Daiichi Nuclear Power Plant. The government ordered a mandatory evacuation from the high radioactive concentration area in Fukushima, which might have forced many evacuees to change particular aspects of their lifestyles. This study assessed the hypothesis that mean body weight and the proportion of overweight/obese individuals would increase among evacuees after versus before the disaster. A longitudinal study examined data collected from 41,633 Japanese participants (mean age, 67 years) sourced from general health checkups conducted in 13 communities between 2008 and 2010. Follow-up examinations were conducted from June 2011 through March 2013. A total of 27,486 participants (12,432 men and 15,054 women; follow-up proportion, 66%) received follow-up examinations after the disaster, with an average follow-up of 1.6 years. Mean body weight significantly increased in both evacuees (n=9,671) and non-evacuees (n=17,815) after the disaster, with greater changes in body weight among evacuees than non-evacuees (+1.2 kg vs +0.3 kg, p<0.001). The proportion of overweight/obese people also increased among evacuees after the disaster, and evacuation was associated with an increased risk of being overweight, despite adjustments for confounding variables. The proportions of overweight evacuees before and after the disaster were 31.8% and 39.4%, respectively, whereas proportions among non-evacuees were 28.3% and 30.3%, respectively. Body weight and the proportion of overweight/obese people increased among residents, especially evacuees, in the evacuation zone of Fukushima prefecture after the Great East Japan Earthquake. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Nowcasting Earthquakes: A Comparison of Induced Earthquakes in Oklahoma and at the Geysers, California

    NASA Astrophysics Data System (ADS)

    Luginbuhl, Molly; Rundle, John B.; Hawkins, Angela; Turcotte, Donald L.

    2018-01-01

    Nowcasting is a new method of statistically classifying seismicity and seismic risk (Rundle et al. 2016). In this paper, the method is applied to the induced seismicity at the Geysers geothermal region in California and the induced seismicity due to fluid injection in Oklahoma. Nowcasting utilizes the catalogs of seismicity in these regions. Two earthquake magnitudes are selected, one large say M_{λ } ≥ 4, and one small say M_{σ } ≥ 2. The method utilizes the number of small earthquakes that occurs between pairs of large earthquakes. The cumulative probability distribution of these values is obtained. The earthquake potential score (EPS) is defined by the number of small earthquakes that has occurred since the last large earthquake, the point where this number falls on the cumulative probability distribution of interevent counts defines the EPS. A major advantage of nowcasting is that it utilizes "natural time", earthquake counts, between events rather than clock time. Thus, it is not necessary to decluster aftershocks and the results are applicable if the level of induced seismicity varies in time. The application of natural time to the accumulation of the seismic hazard depends on the applicability of Gutenberg-Richter (GR) scaling. The increasing number of small earthquakes that occur after a large earthquake can be scaled to give the risk of a large earthquake occurring. To illustrate our approach, we utilize the number of M_{σ } ≥ 2.75 earthquakes in Oklahoma to nowcast the number of M_{λ } ≥ 4.0 earthquakes in Oklahoma. The applicability of the scaling is illustrated during the rapid build-up of injection-induced seismicity between 2012 and 2016, and the subsequent reduction in seismicity associated with a reduction in fluid injections. The same method is applied to the geothermal-induced seismicity at the Geysers, California, for comparison.

  3. The 1906 earthquake and a century of progress in understanding earthquakes and their hazards

    USGS Publications Warehouse

    Zoback, M.L.

    2006-01-01

    The 18 April 1906 San Francisco earthquake killed nearly 3000 people and left 225,000 residents homeless. Three days after the earthquake, an eight-person Earthquake Investigation Commission composed of 25 geologists, seismologists, geodesists, biologists and engineers, as well as some 300 others started work under the supervision of Andrew Lawson to collect and document physical phenomena related to the quake . On 31 May 1906, the commission published a preliminary 17-page report titled "The Report of the State Earthquake Investigation Commission". The report included the bulk of the geological and morphological descriptions of the faulting, detailed reports on shaking intensity, as well as an impressive atlas of 40 oversized maps and folios. Nearly 100 years after its publication, the Commission Report remains a model for post-earthquake investigations. Because the diverse data sets were so complete and carefully documented, researchers continue to apply modern analysis techniques to learn from the 1906 earthquake. While the earthquake marked a seminal event in the history of California, it served as impetus for the birth of modern earthquake science in the United States.

  4. Earthquakes; January-February, 1979

    USGS Publications Warehouse

    Person, W.J.

    1979-01-01

    The first major earthquake (magnitude 7.0 to 7.9) of the year struck in southeastern Alaska in a sparsely populated area on February 28. On January 16, Iran experienced the first destructive earthquake of the year causing a number of casualties and considerable damage. Peru was hit by a destructive earthquake on February 16 that left casualties and damage. A number of earthquakes were experienced in parts of the Untied States, but only minor damage was reported. 

  5. Preliminary results on earthquake triggered landslides for the Haiti earthquake (January 2010)

    NASA Astrophysics Data System (ADS)

    van Westen, Cees; Gorum, Tolga

    2010-05-01

    This study presents the first results on an analysis of the landslides triggered by the Ms 7.0 Haiti earthquake that occurred on January 12, 2010 in the boundary region of the Pacific Plate and the North American plate. The fault is a left lateral strike slip fault with a clear surface expression. According to the USGS earthquake information the Enriquillo-Plantain Garden fault system has not produced any major earthquake in the last 100 years, and historical earthquakes are known from 1860, 1770, 1761, 1751, 1684, 1673, and 1618, though none of these has been confirmed in the field as associated with this fault. We used high resolution satellite imagery available for the pre and post earthquake situations, which were made freely available for the response and rescue operations. We made an interpretation of all co-seismic landslides in the epicentral area. We conclude that the earthquake mainly triggered landslide in the northern slope of the fault-related valley and in a number of isolated area. The earthquake apparently didn't trigger many visible landslides within the slum areas on the slopes in the southern part of Port-au-Prince and Carrefour. We also used ASTER DEM information to relate the landslide occurrences with DEM derivatives.

  6. Turkish Compulsory Earthquake Insurance (TCIP)

    NASA Astrophysics Data System (ADS)

    Erdik, M.; Durukal, E.; Sesetyan, K.

    2009-04-01

    Through a World Bank project a government-sponsored Turkish Catastrophic Insurance Pool (TCIP) is created in 2000 with the essential aim of transferring the government's financial burden of replacing earthquake-damaged housing to international reinsurance and capital markets. Providing coverage to about 2.9 Million homeowners TCIP is the largest insurance program in the country with about 0.5 Billion USD in its own reserves and about 2.3 Billion USD in total claims paying capacity. The total payment for earthquake damage since 2000 (mostly small, 226 earthquakes) amounts to about 13 Million USD. The country-wide penetration rate is about 22%, highest in the Marmara region (30%) and lowest in the south-east Turkey (9%). TCIP is the sole-source provider of earthquake loss coverage up to 90,000 USD per house. The annual premium, categorized on the basis of earthquake zones type of structure, is about US90 for a 100 square meter reinforced concrete building in the most hazardous zone with 2% deductible. The earthquake engineering related shortcomings of the TCIP is exemplified by fact that the average rate of 0.13% (for reinforced concrete buildings) with only 2% deductible is rather low compared to countries with similar earthquake exposure. From an earthquake engineering point of view the risk underwriting (Typification of housing units to be insured, earthquake intensity zonation and the sum insured) of the TCIP needs to be overhauled. Especially for large cities, models can be developed where its expected earthquake performance (and consequently the insurance premium) can be can be assessed on the basis of the location of the unit (microzoned earthquake hazard) and basic structural attributes (earthquake vulnerability relationships). With such an approach, in the future the TCIP can contribute to the control of construction through differentiation of premia on the basis of earthquake vulnerability.

  7. Limitation of the Predominant-Period Estimator for Earthquake Early Warning and the Initial Rupture of Earthquakes

    NASA Astrophysics Data System (ADS)

    Yamada, T.; Ide, S.

    2007-12-01

    Earthquake early warning is an important and challenging issue for the reduction of the seismic damage, especially for the mitigation of human suffering. One of the most important problems in earthquake early warning systems is how immediately we can estimate the final size of an earthquake after we observe the ground motion. It is relevant to the problem whether the initial rupture of an earthquake has some information associated with its final size. Nakamura (1988) developed the Urgent Earthquake Detection and Alarm System (UrEDAS). It calculates the predominant period of the P wave (τp) and estimates the magnitude of an earthquake immediately after the P wave arrival from the value of τpmax, or the maximum value of τp. The similar approach has been adapted by other earthquake alarm systems (e.g., Allen and Kanamori (2003)). To investigate the characteristic of the parameter τp and the effect of the length of the time window (TW) in the τpmax calculation, we analyze the high-frequency recordings of earthquakes at very close distances in the Mponeng mine in South Africa. We find that values of τpmax have upper and lower limits. For larger earthquakes whose source durations are longer than TW, the values of τpmax have an upper limit which depends on TW. On the other hand, the values for smaller earthquakes have a lower limit which is proportional to the sampling interval. For intermediate earthquakes, the values of τpmax are close to their typical source durations. These two limits and the slope for intermediate earthquakes yield an artificial final size dependence of τpmax in a wide size range. The parameter τpmax is useful for detecting large earthquakes and broadcasting earthquake early warnings. However, its dependence on the final size of earthquakes does not suggest that the earthquake rupture is deterministic. This is because τpmax does not always have a direct relation to the physical quantities of an earthquake.

  8. Sun, Moon and Earthquakes

    NASA Astrophysics Data System (ADS)

    Kolvankar, V. G.

    2013-12-01

    During a study conducted to find the effect of Earth tides on the occurrence of earthquakes, for small areas [typically 1000km X1000km] of high-seismicity regions, it was noticed that the Sun's position in terms of universal time [GMT] shows links to the sum of EMD [longitude of earthquake location - longitude of Moon's foot print on earth] and SEM [Sun-Earth-Moon angle]. This paper provides the details of this relationship after studying earthquake data for over forty high-seismicity regions of the world. It was found that over 98% of the earthquakes for these different regions, examined for the period 1973-2008, show a direct relationship between the Sun's position [GMT] and [EMD+SEM]. As the time changes from 00-24 hours, the factor [EMD+SEM] changes through 360 degree, and plotting these two variables for earthquakes from different small regions reveals a simple 45 degree straight-line relationship between them. This relationship was tested for all earthquakes and earthquake sequences for magnitude 2.0 and above. This study conclusively proves how Sun and the Moon govern all earthquakes. Fig. 12 [A+B]. The left-hand figure provides a 24-hour plot for forty consecutive days including the main event (00:58:23 on 26.12.2004, Lat.+3.30, Long+95.980, Mb 9.0, EQ count 376). The right-hand figure provides an earthquake plot for (EMD+SEM) vs GMT timings for the same data. All the 376 events including the main event faithfully follow the straight-line curve.

  9. Are Earthquakes Predictable? A Study on Magnitude Correlations in Earthquake Catalog and Experimental Data

    NASA Astrophysics Data System (ADS)

    Stavrianaki, K.; Ross, G.; Sammonds, P. R.

    2015-12-01

    The clustering of earthquakes in time and space is widely accepted, however the existence of correlations in earthquake magnitudes is more questionable. In standard models of seismic activity, it is usually assumed that magnitudes are independent and therefore in principle unpredictable. Our work seeks to test this assumption by analysing magnitude correlation between earthquakes and their aftershocks. To separate mainshocks from aftershocks, we perform stochastic declustering based on the widely used Epidemic Type Aftershock Sequence (ETAS) model, which allows us to then compare the average magnitudes of aftershock sequences to that of their mainshock. The results of earthquake magnitude correlations were compared with acoustic emissions (AE) from laboratory analog experiments, as fracturing generates both AE at the laboratory scale and earthquakes on a crustal scale. Constant stress and constant strain rate experiments were done on Darley Dale sandstone under confining pressure to simulate depth of burial. Microcracking activity inside the rock volume was analyzed by the AE technique as a proxy for earthquakes. Applying the ETAS model to experimental data allowed us to validate our results and provide for the first time a holistic view on the correlation of earthquake magnitudes. Additionally we search the relationship between the conditional intensity estimates of the ETAS model and the earthquake magnitudes. A positive relation would suggest the existence of magnitude correlations. The aim of this study is to observe any trends of dependency between the magnitudes of aftershock earthquakes and the earthquakes that trigger them.

  10. Putting down roots in earthquake country-Your handbook for earthquakes in the Central United States

    USGS Publications Warehouse

    Contributors: Dart, Richard; McCarthy, Jill; McCallister, Natasha; Williams, Robert A.

    2011-01-01

    This handbook provides information to residents of the Central United States about the threat of earthquakes in that area, particularly along the New Madrid seismic zone, and explains how to prepare for, survive, and recover from such events. It explains the need for concern about earthquakes for those residents and describes what one can expect during and after an earthquake. Much is known about the threat of earthquakes in the Central United States, including where they are likely to occur and what can be done to reduce losses from future earthquakes, but not enough has been done to prepare for future earthquakes. The handbook describes such preparations that can be taken by individual residents before an earthquake to be safe and protect property.

  11. Important Earthquake Engineering Resources

    Science.gov Websites

    PEER logo Pacific Earthquake Engineering Research Center home about peer news events research Engineering Resources Site Map Search Important Earthquake Engineering Resources - American Concrete Institute Motion Observation Systems (COSMOS) - Consortium of Universities for Research in Earthquake Engineering

  12. Repeating Earthquakes Following an Mw 4.4 Earthquake Near Luther, Oklahoma

    NASA Astrophysics Data System (ADS)

    Clements, T.; Keranen, K. M.; Savage, H. M.

    2015-12-01

    An Mw 4.4 earthquake on April 16, 2013 near Luther, OK was one of the earliest M4+ earthquakes in central Oklahoma, following the Prague sequence in 2011. A network of four local broadband seismometers deployed within a day of the Mw 4.4 event, along with six Oklahoma netquake stations, recorded more than 500 aftershocks in the two weeks following the Luther earthquake. Here we use HypoDD (Waldhauser & Ellsworth, 2000) and waveform cross-correlation to obtain precise aftershock locations. The location uncertainty, calculated using the SVD method in HypoDD, is ~15 m horizontally and ~ 35 m vertically. The earthquakes define a near vertical, NE-SW striking fault plane. Events occur at depths from 2 km to 3.5 km within the granitic basement, with a small fraction of events shallower, near the sediment-basement interface. Earthquakes occur within a zone of ~200 meters thickness on either side of the best-fitting fault surface. We use an equivalency class algorithm to identity clusters of repeating events, defined as event pairs with median three-component correlation > 0.97 across common stations (Aster & Scott, 1993). Repeating events occur as doublets of only two events in over 50% of cases; overall, 41% of earthquakes recorded occur as repeating events. The recurrence intervals for the repeating events range from minutes to days, with common recurrence intervals of less than two minutes. While clusters occur in tight dimensions, commonly of 80 m x 200 m, aftershocks occur in 3 distinct ~2km x 2km-sized patches along the fault. Our analysis suggests that with rapidly deployed local arrays, the plethora of ~Mw 4 earthquakes occurring in Oklahoma and Southern Kansas can be used to investigate the earthquake rupture process and the role of damage zones.

  13. Earthquake Hazards.

    ERIC Educational Resources Information Center

    Donovan, Neville

    1979-01-01

    Provides a survey and a review of earthquake activity and global tectonics from the advancement of the theory of continental drift to the present. Topics include: an identification of the major seismic regions of the earth, seismic measurement techniques, seismic design criteria for buildings, and the prediction of earthquakes. (BT)

  14. Earthquakes, May-June 1981

    USGS Publications Warehouse

    Person, W.J.

    1981-01-01

    The months of May and June were somewhat quiet, seismically speaking. There was one major earthquake (7.0-7.9) off the west coast of South Island, New Zealand. The most destructive earthquake during this reporting period was in southern Iran on June 11 which caused fatalities and extensive damage. Peru also experienced a destructive earthquake on June 22 which caused fatalities and damage. In the United States, a number of earthquakes were experienced, but none caused significant damage. 

  15. ViscoSim Earthquake Simulator

    USGS Publications Warehouse

    Pollitz, Fred

    2012-01-01

    Synthetic seismicity simulations have been explored by the Southern California Earthquake Center (SCEC) Earthquake Simulators Group in order to guide long‐term forecasting efforts related to the Unified California Earthquake Rupture Forecast (Tullis et al., 2012a). In this study I describe the viscoelastic earthquake simulator (ViscoSim) of Pollitz, 2009. Recapitulating to a large extent material previously presented by Pollitz (2009, 2011) I describe its implementation of synthetic ruptures and how it differs from other simulators being used by the group.

  16. Earthquake damage orientation to infer seismic parameters in archaeological sites and historical earthquakes

    NASA Astrophysics Data System (ADS)

    Martín-González, Fidel

    2018-01-01

    Studies to provide information concerning seismic parameters and seismic sources of historical and archaeological seismic events are used to better evaluate the seismic hazard of a region. This is of especial interest when no surface rupture is recorded or the seismogenic fault cannot be identified. The orientation pattern of the earthquake damage (ED) (e.g., fallen columns, dropped key stones) that affected architectonic elements of cities after earthquakes has been traditionally used in historical and archaeoseismological studies to infer seismic parameters. However, in the literature depending on the authors, the parameters that can be obtained are contradictory (it has been proposed: the epicenter location, the orientation of the P-waves, the orientation of the compressional strain and the fault kinematics) and authors even question these relations with the earthquake damage. The earthquakes of Lorca in 2011, Christchurch in 2011 and Emilia Romagna in 2012 present an opportunity to measure systematically a large number and wide variety of earthquake damage in historical buildings (the same structures that are used in historical and archaeological studies). The damage pattern orientation has been compared with modern instrumental data, which is not possible in historical and archaeoseismological studies. From measurements and quantification of the orientation patterns in the studied earthquakes, it is observed that there is a systematic pattern of the earthquake damage orientation (EDO) in the proximity of the seismic source (fault trace) (<10 km). The EDO in these earthquakes is normal to the fault trend (±15°). This orientation can be generated by a pulse of motion that in the near fault region has a distinguishable acceleration normal to the fault due to the polarization of the S-waves. Therefore, the earthquake damage orientation could be used to estimate the seismogenic fault trend of historical earthquakes studies where no instrumental data are available.

  17. Earthquakes, March-April, 1993

    USGS Publications Warehouse

    Person, Waverly J.

    1993-01-01

    Worldwide, only one major earthquake (7.0earthquake, a magnitude 7.2 shock, struck the Santa Cruz Islands region in the South Pacific on March 6. Earthquake-related deaths occurred in the Fiji Islands, China, and Peru.

  18. 2016 National Earthquake Conference

    Science.gov Websites

    Thank you to our Presenting Sponsor, California Earthquake Authority. What's New? What's Next ? What's Your Role in Building a National Strategy? The National Earthquake Conference (NEC) is a , state government leaders, social science practitioners, U.S. State and Territorial Earthquake Managers

  19. The music of earthquakes and Earthquake Quartet #1

    USGS Publications Warehouse

    Michael, Andrew J.

    2013-01-01

    Earthquake Quartet #1, my composition for voice, trombone, cello, and seismograms, is the intersection of listening to earthquakes as a seismologist and performing music as a trombonist. Along the way, I realized there is a close relationship between what I do as a scientist and what I do as a musician. A musician controls the source of the sound and the path it travels through their instrument in order to make sound waves that we hear as music. An earthquake is the source of waves that travel along a path through the earth until reaching us as shaking. It is almost as if the earth is a musician and people, including seismologists, are metaphorically listening and trying to understand what the music means.

  20. Impact of the 2001 Tohoku-oki earthquake to Tokyo Metropolitan area observed by the Metropolitan Seismic Observation network (MeSO-net)

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Hayashi, H.; Nakagawa, S.; Sakai, S.; Honda, R.; Kasahara, K.; Obara, K.; Aketagawa, T.; Kimura, H.; Sato, H.; Okaya, D. A.

    2011-12-01

    tomography of P- and S- wave structure, seismic interferometry for shallow structure and using the dense MeSO-net data. We observed the 2011 Tohoku-oki event and its aftershocks including M7.7 event off Ibaraki prefecture, which is the largest aftershock so far. We imaged source radiation energy using the MeSO-net data by the back-projection method (Honda et al., 2011). We found seismic activity in the Kanto region has been activated after the event, suggesting increased seismic hazard in Kanto region even for plate boundary events. We use a new image of PSP and Pacific plate. We evaluate potential zones of the M7+ earthquake on the plate boundary and within the PSP slab which will be used for risk mitigation study by a socio-science group. We will also discuss a future plan to continue our effort in seismic risk mitigation in Tokyo Metropolitan area, stress regime of which is seriously changed by the Tohoku-oki event. This is supported by the Special Project for Earthquake Disaster Mitigation in Tokyo Metropolitan Area

  1. Earthquake triggering in southeast Africa following the 2012 Indian Ocean earthquake

    NASA Astrophysics Data System (ADS)

    Neves, Miguel; Custódio, Susana; Peng, Zhigang; Ayorinde, Adebayo

    2018-02-01

    In this paper we present evidence of earthquake dynamic triggering in southeast Africa. We analysed seismic waveforms recorded at 53 broad-band and short-period stations in order to identify possible increases in the rate of microearthquakes and tremor due to the passage of teleseismic waves generated by the Mw8.6 2012 Indian Ocean earthquake. We found evidence of triggered local earthquakes and no evidence of triggered tremor in the region. We assessed the statistical significance of the increase in the number of local earthquakes using β-statistics. Statistically significant dynamic triggering of local earthquakes was observed at 7 out of the 53 analysed stations. Two of these stations are located in the northeast coast of Madagascar and the other five stations are located in the Kaapvaal Craton, southern Africa. We found no evidence of dynamically triggered seismic activity in stations located near the structures of the East African Rift System. Hydrothermal activity exists close to the stations that recorded dynamic triggering, however, it also exists near the East African Rift System structures where no triggering was observed. Our results suggest that factors other than solely tectonic regime and geothermalism are needed to explain the mechanisms that underlie earthquake triggering.

  2. Toward real-time regional earthquake simulation of Taiwan earthquakes

    NASA Astrophysics Data System (ADS)

    Lee, S.; Liu, Q.; Tromp, J.; Komatitsch, D.; Liang, W.; Huang, B.

    2013-12-01

    We developed a Real-time Online earthquake Simulation system (ROS) to simulate regional earthquakes in Taiwan. The ROS uses a centroid moment tensor solution of seismic events from a Real-time Moment Tensor monitoring system (RMT), which provides all the point source parameters including the event origin time, hypocentral location, moment magnitude and focal mechanism within 2 minutes after the occurrence of an earthquake. Then, all of the source parameters are automatically forwarded to the ROS to perform an earthquake simulation, which is based on a spectral-element method (SEM). We have improved SEM mesh quality by introducing a thin high-resolution mesh layer near the surface to accommodate steep and rapidly varying topography. The mesh for the shallow sedimentary basin is adjusted to reflect its complex geometry and sharp lateral velocity contrasts. The grid resolution at the surface is about 545 m, which is sufficient to resolve topography and tomography data for simulations accurate up to 1.0 Hz. The ROS is also an infrastructural service, making online earthquake simulation feasible. Users can conduct their own earthquake simulation by providing a set of source parameters through the ROS webpage. For visualization, a ShakeMovie and ShakeMap are produced during the simulation. The time needed for one event is roughly 3 minutes for a 70 sec ground motion simulation. The ROS is operated online at the Institute of Earth Sciences, Academia Sinica (http://ros.earth.sinica.edu.tw/). Our long-term goal for the ROS system is to contribute to public earth science outreach and to realize seismic ground motion prediction in real-time.

  3. Geophysical Anomalies and Earthquake Prediction

    NASA Astrophysics Data System (ADS)

    Jackson, D. D.

    2008-12-01

    Finding anomalies is easy. Predicting earthquakes convincingly from such anomalies is far from easy. Why? Why have so many beautiful geophysical abnormalities not led to successful prediction strategies? What is earthquake prediction? By my definition it is convincing information that an earthquake of specified size is temporarily much more likely than usual in a specific region for a specified time interval. We know a lot about normal earthquake behavior, including locations where earthquake rates are higher than elsewhere, with estimable rates and size distributions. We know that earthquakes have power law size distributions over large areas, that they cluster in time and space, and that aftershocks follow with power-law dependence on time. These relationships justify prudent protective measures and scientific investigation. Earthquake prediction would justify exceptional temporary measures well beyond those normal prudent actions. Convincing earthquake prediction would result from methods that have demonstrated many successes with few false alarms. Predicting earthquakes convincingly is difficult for several profound reasons. First, earthquakes start in tiny volumes at inaccessible depth. The power law size dependence means that tiny unobservable ones are frequent almost everywhere and occasionally grow to larger size. Thus prediction of important earthquakes is not about nucleation, but about identifying the conditions for growth. Second, earthquakes are complex. They derive their energy from stress, which is perniciously hard to estimate or model because it is nearly singular at the margins of cracks and faults. Physical properties vary from place to place, so the preparatory processes certainly vary as well. Thus establishing the needed track record for validation is very difficult, especially for large events with immense interval times in any one location. Third, the anomalies are generally complex as well. Electromagnetic anomalies in particular require

  4. Historical earthquake research in Austria

    NASA Astrophysics Data System (ADS)

    Hammerl, Christa

    2017-12-01

    Austria has a moderate seismicity, and on average the population feels 40 earthquakes per year or approximately three earthquakes per month. A severe earthquake with light building damage is expected roughly every 2 to 3 years in Austria. Severe damage to buildings ( I 0 > 8° EMS) occurs significantly less frequently, the average period of recurrence is about 75 years. For this reason the historical earthquake research has been of special importance in Austria. The interest in historical earthquakes in the past in the Austro-Hungarian Empire is outlined, beginning with an initiative of the Austrian Academy of Sciences and the development of historical earthquake research as an independent research field after the 1978 "Zwentendorf plebiscite" on whether the nuclear power plant will start up. The applied methods are introduced briefly along with the most important studies and last but not least as an example of a recently carried out case study, one of the strongest past earthquakes in Austria, the earthquake of 17 July 1670, is presented. The research into historical earthquakes in Austria concentrates on seismic events of the pre-instrumental period. The investigations are not only of historical interest, but also contribute to the completeness and correctness of the Austrian earthquake catalogue, which is the basis for seismic hazard analysis and as such benefits the public, communities, civil engineers, architects, civil protection, and many others.

  5. Unraveling earthquake stresses: Insights from dynamically triggered and induced earthquakes

    NASA Astrophysics Data System (ADS)

    Velasco, A. A.; Alfaro-Diaz, R. A.

    2017-12-01

    Induced seismicity, earthquakes caused by anthropogenic activity, has more than doubled in the last several years resulting from practices related to oil and gas production. Furthermore, large earthquakes have been shown to promote the triggering of other events within two fault lengths (static triggering), due to static stresses caused by physical movement along the fault, and also remotely from the passage of seismic waves (dynamic triggering). Thus, in order to understand the mechanisms for earthquake failure, we investigate regions where natural, induced, and dynamically triggered events occur, and specifically target Oklahoma. We first analyze data from EarthScope's USArray Transportable Array (TA) and local seismic networks implementing an optimized (STA/LTA) detector in order to develop local detection and earthquake catalogs. After we identify triggered events through statistical analysis, and perform a stress analysis to gain insight on the stress-states leading to triggered earthquake failure. We use our observations to determine the role of different transient stresses in contributing to natural and induced seismicity by comparing these stresses to regional stress orientation. We also delineate critically stressed regions of triggered seismicity that may indicate areas susceptible to earthquake hazards associated with sustained fluid injection in provinces of induced seismicity. Anthropogenic injection and extraction activity can alter the stress state and fluid flow within production basins. By analyzing the stress release of these ancient faults caused by dynamic stresses, we may be able to determine if fluids are solely responsible for increased seismic activity in induced regions.

  6. Assessment of Grassland Health Based on Spatial Information Technology in Changji Autonomous Prefecture, Xinjiang

    NASA Astrophysics Data System (ADS)

    Du, M. J.; Zheng, J. H.; Mu, C.

    2018-04-01

    Based on the "pressure-state-response" (PSR) model, comprehensively applied GIS and RS techniques, 20 evaluation indicators were selected based on pressure, state and response, the entropy weight method was used to determine the weight of each index and build a grassland health evaluation system in Changji Prefecture, Xinjiang. Based on this, evaluation and dynamic analysis of grassland health in Changji Prefecture from 2000 to 2016, using GIS/RS technology, the trend of grassland health status in Changji is analyzed and studied. The results show that: 1) Grassland with low health leveld, lower health level, sub-health level, health level and high health level accounts for 1.46 %,27.67 %,38.35 %,29.21 % and 3.31 % of the total area of Changji. Qitai County, Hutubi County, and Manas County are lower health levels, Jimsar County, Changji City, and Mulei County are at a relatively high level, and Fukang City has a healthy level of health. 2) The level of grassland health in Changji County decreased slightly during the 17 years, accounting for 38.42 % of the total area. The area of 23,87 % showed a stable trend, and the improved area accounted for 37.31 % of the vertical surface area.

  7. Analysis of changes in traumatic symptoms and daily life activity of children affected by the 2011 Japan earthquake and tsunami over time.

    PubMed

    Usami, Masahide; Iwadare, Yoshitaka; Watanabe, Kyota; Kodaira, Masaki; Ushijima, Hirokage; Tanaka, Tetsuya; Harada, Maiko; Tanaka, Hiromi; Sasaki, Yoshinori; Saito, Kazuhiko

    2014-01-01

    On March 11, 2011, Japan was struck by a massive earthquake and tsunami. The tsunami caused tremendous damage and traumatized a number of people, including children. This study aimed to compare traumatic symptoms and daily life activity among children 20 months after the 2011 Great East Japan Earthquake and Tsunami with those observed after 8 months. The study comprised two groups. The first comprised 12,524 kindergarten, elementary school, and junior high school children in Ishinomaki City, Miyagi Prefecture, Japan, who were evaluated 8 months after the disaster. The second comprised 10,597 children from the same place who were evaluated 20 months after the disaster. The Post Traumatic Stress Symptoms for Children 15 items (PTSSC-15), a self-completion questionnaire on traumatic symptoms, and a questionnaire on children's daily life were distributed to the children. An effective response was obtained from 11,639 (92.9%, 8 months after) and 10,597 (86.9%, 20 months after) children. The PTSSC-15 score was significantly higher in junior high school girls than in boys. The PTSSC-15 score was significantly higher in 4th-6th grade girls than in boys after 8 months. Elementary and junior high school children evaluated after 20 months had a significantly lower PTSSC-15 score than those evaluated after 8 months. The number of children having breakfast was significantly higher after 8 months than that after 20 months. In both the groups, children of all grades who had breakfast had a significantly lower PTSSC-15 score than those who did not have breakfast. We conclude that traumatic symptoms and daily life activity of children who survived the earthquake and tsunami improved over time.

  8. Earthquake triggering by seismic waves following the landers and hector mine earthquakes

    USGS Publications Warehouse

    Gomberg, J.; Reasenberg, P.A.; Bodin, P.; Harris, R.A.

    2001-01-01

    The proximity and similarity of the 1992, magnitude 7.3 Landers and 1999, magnitude 7.1 Hector Mine earthquakes in California permit testing of earthquake triggering hypotheses not previously possible. The Hector Mine earthquake confirmed inferences that transient, oscillatory 'dynamic' deformations radiated as seismic waves can trigger seismicity rate increases, as proposed for the Landers earthquake1-6. Here we quantify the spatial and temporal patterns of the seismicity rate changes7. The seismicity rate increase was to the north for the Landers earthquake and primarily to the south for the Hector Mine earthquake. We suggest that rupture directivity results in elevated dynamic deformations north and south of the Landers and Hector Mine faults, respectively, as evident in the asymmetry of the recorded seismic velocity fields. Both dynamic and static stress changes seem important for triggering in the near field with dynamic stress changes dominating at greater distances. Peak seismic velocities recorded for each earthquake suggest the existence of, and place bounds on, dynamic triggering thresholds. These thresholds vary from a few tenths to a few MPa in most places, depend on local conditions, and exceed inferred static thresholds by more than an order of magnitude. At some sites, the onset of triggering was delayed until after the dynamic deformations subsided. Physical mechanisms consistent with all these observations may be similar to those that give rise to liquefaction or cyclic fatigue.

  9. Analysis of pre-earthquake ionospheric anomalies before the global M = 7.0+ earthquakes in 2010

    NASA Astrophysics Data System (ADS)

    Yao, Y. B.; Chen, P.; Zhang, S.; Chen, J. J.; Yan, F.; Peng, W. F.

    2012-03-01

    The pre-earthquake ionospheric anomalies that occurred before the global M = 7.0+ earthquakes in 2010 are investigated using the total electron content (TEC) from the global ionosphere map (GIM). We analyze the possible causes of the ionospheric anomalies based on the space environment and magnetic field status. Results show that some anomalies are related to the earthquakes. By analyzing the time of occurrence, duration, and spatial distribution of these ionospheric anomalies, a number of new conclusions are drawn, as follows: earthquake-related ionospheric anomalies are not bound to appear; both positive and negative anomalies are likely to occur; and the earthquake-related ionospheric anomalies discussed in the current study occurred 0-2 days before the associated earthquakes and in the afternoon to sunset (i.e. between 12:00 and 20:00 local time). Pre-earthquake ionospheric anomalies occur mainly in areas near the epicenter. However, the maximum affected area in the ionosphere does not coincide with the vertical projection of the epicenter of the subsequent earthquake. The directions deviating from the epicenters do not follow a fixed rule. The corresponding ionospheric effects can also be observed in the magnetically conjugated region. However, the probability of the anomalies appearance and extent of the anomalies in the magnetically conjugated region are smaller than the anomalies near the epicenter. Deep-focus earthquakes may also exhibit very significant pre-earthquake ionospheric anomalies.

  10. Mortality among Japanese construction workers in Mie Prefecture

    PubMed Central

    Sun, J; Kubota, H; Hisanaga, N; Shibata, E; Kamijima, M; Nakamura, K

    2002-01-01

    Aims: A historical cohort mortality study was conducted among 17 668 members of the Construction Workers' Health Insurance Society of Mie Prefecture in Japan, in order to verify the relation between occupations and mortality status. Methods: The cohort was followed from 2 April 1973 to 1 April 1998. Standardised mortality ratios (SMR) were calculated for all members and each job classification. Results: 98.7% of the members were traced successfully until the date when the follow up terminated. When all members were considered together, significant excess mortality was observed for "accidents and adverse effects". Significant excess mortalities were also observed for lung cancers among scaffold men and ironworkers, for cancer of the oesophagus among plumbers, and for "chronic liver disease and cirrhosis" among scaffold men and painters. Conclusion: Results suggest that more detailed investigations, which would include some minor job classifications should be undertaken. This is an updated cohort study which was partially completed in 1997. PMID:12151606

  11. Modeling, Forecasting and Mitigating Extreme Earthquakes

    NASA Astrophysics Data System (ADS)

    Ismail-Zadeh, A.; Le Mouel, J.; Soloviev, A.

    2012-12-01

    Recent earthquake disasters highlighted the importance of multi- and trans-disciplinary studies of earthquake risk. A major component of earthquake disaster risk analysis is hazards research, which should cover not only a traditional assessment of ground shaking, but also studies of geodetic, paleoseismic, geomagnetic, hydrological, deep drilling and other geophysical and geological observations together with comprehensive modeling of earthquakes and forecasting extreme events. Extreme earthquakes (large magnitude and rare events) are manifestations of complex behavior of the lithosphere structured as a hierarchical system of blocks of different sizes. Understanding of physics and dynamics of the extreme events comes from observations, measurements and modeling. A quantitative approach to simulate earthquakes in models of fault dynamics will be presented. The models reproduce basic features of the observed seismicity (e.g., the frequency-magnitude relationship, clustering of earthquakes, occurrence of extreme seismic events). They provide a link between geodynamic processes and seismicity, allow studying extreme events, influence of fault network properties on seismic patterns and seismic cycles, and assist, in a broader sense, in earthquake forecast modeling. Some aspects of predictability of large earthquakes (how well can large earthquakes be predicted today?) will be also discussed along with possibilities in mitigation of earthquake disasters (e.g., on 'inverse' forensic investigations of earthquake disasters).

  12. Extending earthquakes' reach through cascading.

    PubMed

    Marsan, David; Lengliné, Olivier

    2008-02-22

    Earthquakes, whatever their size, can trigger other earthquakes. Mainshocks cause aftershocks to occur, which in turn activate their own local aftershock sequences, resulting in a cascade of triggering that extends the reach of the initial mainshock. A long-lasting difficulty is to determine which earthquakes are connected, either directly or indirectly. Here we show that this causal structure can be found probabilistically, with no a priori model nor parameterization. Large regional earthquakes are found to have a short direct influence in comparison to the overall aftershock sequence duration. Relative to these large mainshocks, small earthquakes collectively have a greater effect on triggering. Hence, cascade triggering is a key component in earthquake interactions.

  13. Earthquake Catalogue of the Caucasus

    NASA Astrophysics Data System (ADS)

    Godoladze, T.; Gok, R.; Tvaradze, N.; Tumanova, N.; Gunia, I.; Onur, T.

    2016-12-01

    The Caucasus has a documented historical catalog stretching back to the beginning of the Christian era. Most of the largest historical earthquakes prior to the 19th century are assumed to have occurred on active faults of the Greater Caucasus. Important earthquakes include the Samtskhe earthquake of 1283 (Ms˜7.0, Io=9); Lechkhumi-Svaneti earthquake of 1350 (Ms˜7.0, Io=9); and the Alaverdi earthquake of 1742 (Ms˜6.8, Io=9). Two significant historical earthquakes that may have occurred within the Javakheti plateau in the Lesser Caucasus are the Tmogvi earthquake of 1088 (Ms˜6.5, Io=9) and the Akhalkalaki earthquake of 1899 (Ms˜6.3, Io =8-9). Large earthquakes that occurred in the Caucasus within the period of instrumental observation are: Gori 1920; Tabatskuri 1940; Chkhalta 1963; Racha earthquake of 1991 (Ms=7.0), is the largest event ever recorded in the region; Barisakho earthquake of 1992 (M=6.5); Spitak earthquake of 1988 (Ms=6.9, 100 km south of Tbilisi), which killed over 50,000 people in Armenia. Recently, permanent broadband stations have been deployed across the region as part of the various national networks (Georgia (˜25 stations), Azerbaijan (˜35 stations), Armenia (˜14 stations)). The data from the last 10 years of observation provides an opportunity to perform modern, fundamental scientific investigations. In order to improve seismic data quality a catalog of all instrumentally recorded earthquakes has been compiled by the IES (Institute of Earth Sciences/NSMC, Ilia State University) in the framework of regional joint project (Armenia, Azerbaijan, Georgia, Turkey, USA) "Probabilistic Seismic Hazard Assessment (PSHA) in the Caucasus. The catalogue consists of more then 80,000 events. First arrivals of each earthquake of Mw>=4.0 have been carefully examined. To reduce calculation errors, we corrected arrivals from the seismic records. We improved locations of the events and recalculate Moment magnitudes in order to obtain unified magnitude

  14. Earthquakes, July-August 1992

    USGS Publications Warehouse

    Person, W.J.

    1992-01-01

    There were two major earthquakes (7.0≤M<8.0) during this reporting period. A magnitude 7.5 earthquake occurred in Kyrgyzstan on August 19 and a magnitude 7.0 quake struck the Ascension Island region on August 28. In southern California, aftershocks of the magnitude 7.6 earthquake on June 28, 1992, continued. One of these aftershocks caused damage and injuries, and at least one other aftershock caused additional damage. Earthquake-related fatalities were reportred in Kyrgzstan and Pakistan. 

  15. S-net project: Construction of large scale seafloor observatory network for tsunamis and earthquakes in Japan

    NASA Astrophysics Data System (ADS)

    Mochizuki, M.; Kanazawa, T.; Uehira, K.; Shimbo, T.; Shiomi, K.; Kunugi, T.; Aoi, S.; Matsumoto, T.; Sekiguchi, S.; Yamamoto, N.; Takahashi, N.; Shinohara, M.; Yamada, T.

    2016-12-01

    National Research Institute for Earth Science and Disaster Resilience ( NIED ) has launched the project of constructing an observatory network for tsunamis and earthquakes on the seafloor. The observatory network was named "S-net, Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench". The S-net consists of 150 seafloor observatories which are connected in line with submarine optical cables. The total length of submarine optical cable is about 5,700 km. The S-net system extends along Kuril and Japan trenches around Japan islands from north to south covering the area between southeast off island of Hokkaido and off the Boso Peninsula, Chiba Prefecture. The project has been financially supported by MEXT Japan. An observatory package is 34cm in diameter and 226cm long. Each observatory equips two units of a high sensitive water-depth sensor as a tsunami meter and four sets of three-component seismometers. The water-depth sensor has measurement resolution of sub-centimeter level. Combination of multiple seismometers secures wide dynamic range and robustness of the observation that are needed for early earthquake warning. The S-net is composed of six segment networks that consists of about 25 observatories and 800-1,600km length submarine optical cable. Five of six segment networks except the one covering the outer rise area of the Japan Trench has been already installed. The data from the observatories on those five segment networks are being transferred to the data center at NIED on a real-time basis, and then verification of data integrity are being carried out at the present moment. Installation of the last segment network of the S-net, that is, the outer rise one is scheduled to be finished within FY2016. Full-scale operation of the S-net will start at FY2017. We will report construction and operation of the S-net submarine cable system as well as the outline of the obtained data in this presentation.

  16. Earthquakes: Recurrence and Interoccurrence Times

    NASA Astrophysics Data System (ADS)

    Abaimov, S. G.; Turcotte, D. L.; Shcherbakov, R.; Rundle, J. B.; Yakovlev, G.; Goltz, C.; Newman, W. I.

    2008-04-01

    The purpose of this paper is to discuss the statistical distributions of recurrence times of earthquakes. Recurrence times are the time intervals between successive earthquakes at a specified location on a specified fault. Although a number of statistical distributions have been proposed for recurrence times, we argue in favor of the Weibull distribution. The Weibull distribution is the only distribution that has a scale-invariant hazard function. We consider three sets of characteristic earthquakes on the San Andreas fault: (1) The Parkfield earthquakes, (2) the sequence of earthquakes identified by paleoseismic studies at the Wrightwood site, and (3) an example of a sequence of micro-repeating earthquakes at a site near San Juan Bautista. In each case we make a comparison with the applicable Weibull distribution. The number of earthquakes in each of these sequences is too small to make definitive conclusions. To overcome this difficulty we consider a sequence of earthquakes obtained from a one million year “Virtual California” simulation of San Andreas earthquakes. Very good agreement with a Weibull distribution is found. We also obtain recurrence statistics for two other model studies. The first is a modified forest-fire model and the second is a slider-block model. In both cases good agreements with Weibull distributions are obtained. Our conclusion is that the Weibull distribution is the preferred distribution for estimating the risk of future earthquakes on the San Andreas fault and elsewhere.

  17. Natural Time and Nowcasting Earthquakes: Are Large Global Earthquakes Temporally Clustered?

    NASA Astrophysics Data System (ADS)

    Luginbuhl, Molly; Rundle, John B.; Turcotte, Donald L.

    2018-02-01

    The objective of this paper is to analyze the temporal clustering of large global earthquakes with respect to natural time, or interevent count, as opposed to regular clock time. To do this, we use two techniques: (1) nowcasting, a new method of statistically classifying seismicity and seismic risk, and (2) time series analysis of interevent counts. We chose the sequences of M_{λ } ≥ 7.0 and M_{λ } ≥ 8.0 earthquakes from the global centroid moment tensor (CMT) catalog from 2004 to 2016 for analysis. A significant number of these earthquakes will be aftershocks of the largest events, but no satisfactory method of declustering the aftershocks in clock time is available. A major advantage of using natural time is that it eliminates the need for declustering aftershocks. The event count we utilize is the number of small earthquakes that occur between large earthquakes. The small earthquake magnitude is chosen to be as small as possible, such that the catalog is still complete based on the Gutenberg-Richter statistics. For the CMT catalog, starting in 2004, we found the completeness magnitude to be M_{σ } ≥ 5.1. For the nowcasting method, the cumulative probability distribution of these interevent counts is obtained. We quantify the distribution using the exponent, β, of the best fitting Weibull distribution; β = 1 for a random (exponential) distribution. We considered 197 earthquakes with M_{λ } ≥ 7.0 and found β = 0.83 ± 0.08. We considered 15 earthquakes with M_{λ } ≥ 8.0, but this number was considered too small to generate a meaningful distribution. For comparison, we generated synthetic catalogs of earthquakes that occur randomly with the Gutenberg-Richter frequency-magnitude statistics. We considered a synthetic catalog of 1.97 × 10^5 M_{λ } ≥ 7.0 earthquakes and found β = 0.99 ± 0.01. The random catalog converted to natural time was also random. We then generated 1.5 × 10^4 synthetic catalogs with 197 M_{λ } ≥ 7.0 in each catalog and

  18. Earthquake and Tsunami booklet based on two Indonesia earthquakes

    NASA Astrophysics Data System (ADS)

    Hayashi, Y.; Aci, M.

    2014-12-01

    Many destructive earthquakes occurred during the last decade in Indonesia. These experiences are very important precepts for the world people who live in earthquake and tsunami countries. We are collecting the testimonies of tsunami survivors to clarify successful evacuation process and to make clear the characteristic physical behaviors of tsunami near coast. We research 2 tsunami events, 2004 Indian Ocean tsunami and 2010 Mentawai slow earthquake tsunami. Many video and photographs were taken by people at some places in 2004 Indian ocean tsunami disaster; nevertheless these were few restricted points. We didn't know the tsunami behavior in another place. In this study, we tried to collect extensive information about tsunami behavior not only in many places but also wide time range after the strong shake. In Mentawai case, the earthquake occurred in night, so there are no impressive photos. To collect detail information about evacuation process from tsunamis, we contrived the interview method. This method contains making pictures of tsunami experience from the scene of victims' stories. In 2004 Aceh case, all survivors didn't know tsunami phenomena. Because there were no big earthquakes with tsunami for one hundred years in Sumatra region, public people had no knowledge about tsunami. This situation was highly improved in 2010 Mentawai case. TV programs and NGO or governmental public education programs about tsunami evacuation are widespread in Indonesia. Many people know about fundamental knowledge of earthquake and tsunami disasters. We made drill book based on victim's stories and painted impressive scene of 2 events. We used the drill book in disaster education event in school committee of west Java. About 80 % students and teachers evaluated that the contents of the drill book are useful for correct understanding.

  19. Changes in air temperature and its relation to ambulance transports due to heat stroke in all 47 prefectures of Japan.

    PubMed

    Murakami, Shoko; Miyatake, Nobuyuki; Sakano, Noriko

    2012-09-01

    Changes in air temperature and its relation to ambulance transports due to heat stroke in all 47 prefectures, in Japan were evaluated. Data on air temperature were obtained from the Japanese Meteorological Agency. Data on ambulance transports due to heat stroke was directly obtained from the Fire and Disaster Management Agency, Japan. We also used the number of deaths due to heat stroke from the Ministry of Health, Labour and Welfare, Japan, and population data from the Ministry of Internal Affairs and Communications. Chronological changes in parameters of air temperature were analyzed. In addition, the relation between air temperature and ambulance transports due to heat stroke in August 2010 was also evaluated by using an ecological study. Positive and significant changes in the parameters of air temperature that is, the mean air temperature, mean of the highest air temperature, and mean of the lowest air temperature were noted in all 47 prefectures. In addition, changes in air temperature were accelerated when adjusted for observation years. Ambulance transports due to heat stroke was significantly correlated with air temperature in the ecological study. The highest air temperature was significantly linked to ambulance transports due to heat stroke, especially in elderly subjects. Global warming was demonstrated in all 47 prefectures in Japan. In addition, the higher air temperature was closely associated with higher ambulance transports due to heat stroke in Japan.

  20. Earthquakes: hydrogeochemical precursors

    USGS Publications Warehouse

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  1. Earthquakes, September-October 1993

    USGS Publications Warehouse

    Person, W.J.

    1993-01-01

    The fatalities in the United States were caused by two earthquakes in southern Oregon on September 21. These earthquakes, both with magnitude 6.0 and separated in time by about 2 hrs, led to the deaths of two people. One of these deaths was apparently due to a heart attack induced by the earthquake

  2. Children's Ideas about Earthquakes

    ERIC Educational Resources Information Center

    Simsek, Canan Lacin

    2007-01-01

    Earthquake, a natural disaster, is among the fundamental problems of many countries. If people know how to protect themselves from earthquake and arrange their life styles in compliance with this, damage they will suffer will reduce to that extent. In particular, a good training regarding earthquake to be received in primary schools is considered…

  3. Evaluation of School Environmental Programs Regarding the Objectives for the Environmentally Literate Students, of Heraklion, Greece Prefecture

    ERIC Educational Resources Information Center

    Kalathak, Maria

    2015-01-01

    This evaluation research concerns the aims and objectives for creating the future environmentally literate citizen through the environmental programs (PEEs) of Secondary Education of Heraklion prefecture, Crete, Greece. An evaluation tool applied on the application forms and the final reports of the programs, in order to asses how sustainable they…

  4. Excel, Earthquakes, and Moneyball: exploring Cascadia earthquake probabilities using spreadsheets and baseball analogies

    NASA Astrophysics Data System (ADS)

    Campbell, M. R.; Salditch, L.; Brooks, E. M.; Stein, S.; Spencer, B. D.

    2017-12-01

    Much recent media attention focuses on Cascadia's earthquake hazard. A widely cited magazine article starts "An earthquake will destroy a sizable portion of the coastal Northwest. The question is when." Stories include statements like "a massive earthquake is overdue", "in the next 50 years, there is a 1-in-10 chance a "really big one" will erupt," or "the odds of the big Cascadia earthquake happening in the next fifty years are roughly one in three." These lead students to ask where the quoted probabilities come from and what they mean. These probability estimates involve two primary choices: what data are used to describe when past earthquakes happened and what models are used to forecast when future earthquakes will happen. The data come from a 10,000-year record of large paleoearthquakes compiled from subsidence data on land and turbidites, offshore deposits recording submarine slope failure. Earthquakes seem to have happened in clusters of four or five events, separated by gaps. Earthquakes within a cluster occur more frequently and regularly than in the full record. Hence the next earthquake is more likely if we assume that we are in the recent cluster that started about 1700 years ago, than if we assume the cluster is over. Students can explore how changing assumptions drastically changes probability estimates using easy-to-write and display spreadsheets, like those shown below. Insight can also come from baseball analogies. The cluster issue is like deciding whether to assume that a hitter's performance in the next game is better described by his lifetime record, or by the past few games, since he may be hitting unusually well or in a slump. The other big choice is whether to assume that the probability of an earthquake is constant with time, or is small immediately after one occurs and then grows with time. This is like whether to assume that a player's performance is the same from year to year, or changes over their career. Thus saying "the chance of

  5. Do Earthquakes Shake Stock Markets?

    PubMed

    Ferreira, Susana; Karali, Berna

    2015-01-01

    This paper examines how major earthquakes affected the returns and volatility of aggregate stock market indices in thirty-five financial markets over the last twenty years. Results show that global financial markets are resilient to shocks caused by earthquakes even if these are domestic. Our analysis reveals that, in a few instances, some macroeconomic variables and earthquake characteristics (gross domestic product per capita, trade openness, bilateral trade flows, earthquake magnitude, a tsunami indicator, distance to the epicenter, and number of fatalities) mediate the impact of earthquakes on stock market returns, resulting in a zero net effect. However, the influence of these variables is market-specific, indicating no systematic pattern across global capital markets. Results also demonstrate that stock market volatility is unaffected by earthquakes, except for Japan.

  6. Toward real-time regional earthquake simulation II: Real-time Online earthquake Simulation (ROS) of Taiwan earthquakes

    NASA Astrophysics Data System (ADS)

    Lee, Shiann-Jong; Liu, Qinya; Tromp, Jeroen; Komatitsch, Dimitri; Liang, Wen-Tzong; Huang, Bor-Shouh

    2014-06-01

    We developed a Real-time Online earthquake Simulation system (ROS) to simulate regional earthquakes in Taiwan. The ROS uses a centroid moment tensor solution of seismic events from a Real-time Moment Tensor monitoring system (RMT), which provides all the point source parameters including the event origin time, hypocentral location, moment magnitude and focal mechanism within 2 min after the occurrence of an earthquake. Then, all of the source parameters are automatically forwarded to the ROS to perform an earthquake simulation, which is based on a spectral-element method (SEM). A new island-wide, high resolution SEM mesh model is developed for the whole Taiwan in this study. We have improved SEM mesh quality by introducing a thin high-resolution mesh layer near the surface to accommodate steep and rapidly varying topography. The mesh for the shallow sedimentary basin is adjusted to reflect its complex geometry and sharp lateral velocity contrasts. The grid resolution at the surface is about 545 m, which is sufficient to resolve topography and tomography data for simulations accurate up to 1.0 Hz. The ROS is also an infrastructural service, making online earthquake simulation feasible. Users can conduct their own earthquake simulation by providing a set of source parameters through the ROS webpage. For visualization, a ShakeMovie and ShakeMap are produced during the simulation. The time needed for one event is roughly 3 min for a 70 s ground motion simulation. The ROS is operated online at the Institute of Earth Sciences, Academia Sinica (http://ros.earth.sinica.edu.tw/). Our long-term goal for the ROS system is to contribute to public earth science outreach and to realize seismic ground motion prediction in real-time.

  7. Sedimentary Signatures of Submarine Earthquakes: Deciphering the Extent of Sediment Remobilization from the 2011 Tohoku Earthquake and Tsunami and 2010 Haiti Earthquake

    NASA Astrophysics Data System (ADS)

    McHugh, C. M.; Seeber, L.; Moernaut, J.; Strasser, M.; Kanamatsu, T.; Ikehara, K.; Bopp, R.; Mustaque, S.; Usami, K.; Schwestermann, T.; Kioka, A.; Moore, L. M.

    2017-12-01

    The 2004 Sumatra-Andaman Mw9.3 and the 2011 Tohoku (Japan) Mw9.0 earthquakes and tsunamis were huge geological events with major societal consequences. Both were along subduction boundaries and ruptured portions of these boundaries that had been deemed incapable of such events. Submarine strike-slip earthquakes, such as the 2010 Mw7.0 in Haiti, are smaller but may be closer to population centers and can be similarly catastrophic. Both classes of earthquakes remobilize sediment and leave distinct signatures in the geologic record by a wide range of processes that depends on both environment and earthquake characteristics. Understanding them has the potential of greatly expanding the record of past earthquakes, which is critical for geohazard analysis. Recent events offer precious ground truth about the earthquakes and short-lived radioisotopes offer invaluable tools to identify sediments they remobilized. In the 2011 Mw9 Japan earthquake they document the spatial extent of remobilized sediment from water depths of 626m in the forearc slope to trench depths of 8000m. Subbottom profiles, multibeam bathymetry and 40 piston cores collected by the R/V Natsushima and R/V Sonne expeditions to the Japan Trench document multiple turbidites and high-density flows. Core tops enriched in xs210Pb,137Cs and 134Cs reveal sediment deposited by the 2011 Tohoku earthquake and tsunami. The thickest deposits (2m) were documented on a mid-slope terrace and trench (4000-8000m). Sediment was deposited on some terraces (600-3000m), but shed from the steep forearc slope (3000-4000m). The 2010 Haiti mainshock ruptured along the southern flank of Canal du Sud and triggered multiple nearshore sediment failures, generated turbidity currents and stirred fine sediment into suspension throughout this basin. A tsunami was modeled to stem from both sediment failures and tectonics. Remobilized sediment was tracked with short-lived radioisotopes from the nearshore, slope, in fault basins including the

  8. WGCEP Historical California Earthquake Catalog

    USGS Publications Warehouse

    Felzer, Karen R.; Cao, Tianqing

    2008-01-01

    This appendix provides an earthquake catalog for California and the surrounding area. Our goal is to provide a listing for all known M > 5.5 earthquakes that occurred from 1850-1932 and all known M > 4.0 earthquakes that occurred from 1932-2006 within the region of 31.0 to 43.0 degrees North and -126.0 to -114.0 degrees West. Some pre-1932 earthquakes 4 5, before the Northern California network was online. Some earthquakes from 1900-1932, and particularly from 1910-1932 are also based on instrumental readings, but the quality of the instrumental record and the resulting analysis are much less precise than for later listings. A partial exception is for some of the largest earthquakes, such as the San Francisco earthquake of April 18, 1906, for which global teleseismic records (Wald et al. 1993) and geodetic measurements (Thatcher et al. 1906) have been used to help determine magnitudes.

  9. Earthquakes, September-October 1978

    USGS Publications Warehouse

    Person, W.J.

    1979-01-01

    The months of September and October were somewhat quiet seismically speaking. One major earthquake, magnitude (M) 7.7 occurred in Iran on September 16. In Germany, a magntidue 5.0 earthquake caused damage and considerable alarm to many people in parts of that country. In the United States, the largest earthquake occurred along the California-Nevada border region. 

  10. Earthquakes, March-April 1991

    USGS Publications Warehouse

    Person, W.J.

    1992-01-01

    Two major earthquakes (7.0-7.9) occurred during this reporting period: a magnitude 7.6 in Costa Rica on April 22 and a magntidue 7.0 in the USSR on April 29. Destructive earthquakes hit northern Peru on April 4 and 5. There were no destructive earthquakes in the United States during this period. 

  11. Can We Predict Earthquakes?

    ScienceCinema

    Johnson, Paul

    2018-01-16

    The only thing we know for sure about earthquakes is that one will happen again very soon. Earthquakes pose a vital yet puzzling set of research questions that have confounded scientists for decades, but new ways of looking at seismic information and innovative laboratory experiments are offering tantalizing clues to what triggers earthquakes — and when.

  12. Earthquake and Schools. [Videotape].

    ERIC Educational Resources Information Center

    Federal Emergency Management Agency, Washington, DC.

    Designing schools to make them more earthquake resistant and protect children from the catastrophic collapse of the school building is discussed in this videotape. It reveals that 44 of the 50 U.S. states are vulnerable to earthquake, but most schools are structurally unprepared to take on the stresses that earthquakes exert. The cost to the…

  13. Earthquakes, September-October 1991

    USGS Publications Warehouse

    Person, W.J.

    1992-01-01

    There were two major earthquakes (7.0-7.9) during this reporting period. the first was in the Solomon Islands on October 14 and the second was in India on October 19. Earthquake-related deaths were reported in Guatemala and India. Htere were no significant earthquakes in the United States during the period covered in this report. 

  14. Earthquakes in Arkansas and vicinity 1699-2010

    USGS Publications Warehouse

    Dart, Richard L.; Ausbrooks, Scott M.

    2011-01-01

    This map summarizes approximately 300 years of earthquake activity in Arkansas. It is one in a series of similar State earthquake history maps. Work on the Arkansas map was done in collaboration with the Arkansas Geological Survey. The earthquake data plotted on the map are from several sources: the Arkansas Geological Survey, the Center for Earthquake Research and Information, the National Center for Earthquake Engineering Research, and the Mississippi Department of Environmental Quality. In addition to earthquake locations, other materials presented include seismic hazard and isoseismal maps and related text. Earthquakes are a legitimate concern in Arkansas and parts of adjacent states. Arkansas has undergone a number of significant felt earthquakes since 1811. At least two of these events caused property damage: a magnitude 4.7 earthquake in 1931, and a magnitude 4.3 earthquake in 1967. The map shows all historical and instrumentally located earthquakes in Arkansas and vicinity between 1811 and 2010. The largest historic earthquake in the vicinity of the State was an intensity XI event, on December 16, 1811; the first earthquake in the New Madrid sequence. This violent event and the earthquakes that followed caused considerable damage to the then sparsely settled region.

  15. Earthquake Forecasting System in Italy

    NASA Astrophysics Data System (ADS)

    Falcone, G.; Marzocchi, W.; Murru, M.; Taroni, M.; Faenza, L.

    2017-12-01

    In Italy, after the 2009 L'Aquila earthquake, a procedure was developed for gathering and disseminating authoritative information about the time dependence of seismic hazard to help communities prepare for a potentially destructive earthquake. The most striking time dependency of the earthquake occurrence process is the time clustering, which is particularly pronounced in time windows of days and weeks. The Operational Earthquake Forecasting (OEF) system that is developed at the Seismic Hazard Center (Centro di Pericolosità Sismica, CPS) of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) is the authoritative source of seismic hazard information for Italian Civil Protection. The philosophy of the system rests on a few basic concepts: transparency, reproducibility, and testability. In particular, the transparent, reproducible, and testable earthquake forecasting system developed at CPS is based on ensemble modeling and on a rigorous testing phase. Such phase is carried out according to the guidance proposed by the Collaboratory for the Study of Earthquake Predictability (CSEP, international infrastructure aimed at evaluating quantitatively earthquake prediction and forecast models through purely prospective and reproducible experiments). In the OEF system, the two most popular short-term models were used: the Epidemic-Type Aftershock Sequences (ETAS) and the Short-Term Earthquake Probabilities (STEP). Here, we report the results from OEF's 24hour earthquake forecasting during the main phases of the 2016-2017 sequence occurred in Central Apennines (Italy).

  16. The 2008 Wenchuan Earthquake and the Rise and Fall of Earthquake Prediction in China

    NASA Astrophysics Data System (ADS)

    Chen, Q.; Wang, K.

    2009-12-01

    Regardless of the future potential of earthquake prediction, it is presently impractical to rely on it to mitigate earthquake disasters. The practical approach is to strengthen the resilience of our built environment to earthquakes based on hazard assessment. But this was not common understanding in China when the M 7.9 Wenchuan earthquake struck the Sichuan Province on 12 May 2008, claiming over 80,000 lives. In China, earthquake prediction is a government-sanctioned and law-regulated measure of disaster prevention. A sudden boom of the earthquake prediction program in 1966-1976 coincided with a succession of nine M > 7 damaging earthquakes in the densely populated region of the country and the political chaos of the Cultural Revolution. It climaxed with the prediction of the 1975 Haicheng earthquake, which was due mainly to an unusually pronounced foreshock sequence and the extraordinary readiness of some local officials to issue imminent warning and evacuation order. The Haicheng prediction was a success in practice and yielded useful lessons, but the experience cannot be applied to most other earthquakes and cultural environments. Since the disastrous Tangshan earthquake in 1976 that killed over 240,000 people, there have been two opposite trends in China: decreasing confidence in prediction and increasing emphasis on regulating construction design for earthquake resilience. In 1976, most of the seismic intensity XI areas of Tangshan were literally razed to the ground, but in 2008, many buildings in the intensity XI areas of Wenchuan did not collapse. Prediction did not save life in either of these events; the difference was made by construction standards. For regular buildings, there was no seismic design in Tangshan to resist any earthquake shaking in 1976, but limited seismic design was required for the Wenchuan area in 2008. Although the construction standards were later recognized to be too low, those buildings that met the standards suffered much less

  17. Geomorphic features of surface ruptures associated with the 2016 Kumamoto earthquake in and around the downtown of Kumamoto City, and implications on triggered slip along active faults

    NASA Astrophysics Data System (ADS)

    Goto, Hideaki; Tsutsumi, Hiroyuki; Toda, Shinji; Kumahara, Yasuhiro

    2017-02-01

    The 30-km-long surface ruptures associated with the M w 7.0 ( M j 7.3) earthquake at 01:25 JST on April 16 in Kumamoto Prefecture appeared along the previously mapped 100-km-long active fault called the Futagawa-Hinagu fault zone (FHFZ). The surface ruptures appeared to have extended further west out of the main FHFZ into the Kumamoto Plain. Although InSAR analysis by Geospatial Information Authority of Japan (GSI) indicated coseismic surface deformation in and around the downtown of Kumamoto City, the surface ruptures have not been clearly mapped in the central part of the Kumamoto Plain, and whether there are other active faults other than the Futagawa fault in the Kumamoto Plain remained unclear. We produced topographical stereo images (anaglyph) from 5-m-mesh digital elevation model of GSI, which was generated from light detection and ranging data. We interpreted them and identified that several SW-sloping river terraces formed after the deposition of the pyroclastic flow deposits related to the latest large eruption of the Aso caldera (86.8-87.3 ka) are cut and deformed by several NW-trending flexure scarps down to the southwest. These 5.4-km-long scarps that cut across downtown Kumamoto were identified for the first time, and we name them as the Suizenji fault zone. Surface deformation such as continuous cracks, tilts, and monoclinal folding associated with the main shock of the 2016 Kumamoto earthquake was observed in the field along the fault zone. The amount of vertical deformation ( 0.1 m) along this fault associated with the 2016 Kumamoto earthquake was quite small compared to the empirically calculated coseismic slip (0.5 m) based on the fault length. We thus suggest that the slip on this fault zone was triggered by the Kumamoto earthquake, but the fault zone has potential to generate an earthquake with larger slip that poses a high seismic risk in downtown Kumamoto area.[Figure not available: see fulltext.

  18. Earthquake impact scale

    USGS Publications Warehouse

    Wald, D.J.; Jaiswal, K.S.; Marano, K.D.; Bausch, D.

    2011-01-01

    With the advent of the USGS prompt assessment of global earthquakes for response (PAGER) system, which rapidly assesses earthquake impacts, U.S. and international earthquake responders are reconsidering their automatic alert and activation levels and response procedures. To help facilitate rapid and appropriate earthquake response, an Earthquake Impact Scale (EIS) is proposed on the basis of two complementary criteria. On the basis of the estimated cost of damage, one is most suitable for domestic events; the other, on the basis of estimated ranges of fatalities, is generally more appropriate for global events, particularly in developing countries. Simple thresholds, derived from the systematic analysis of past earthquake impact and associated response levels, are quite effective in communicating predicted impact and response needed after an event through alerts of green (little or no impact), yellow (regional impact and response), orange (national-scale impact and response), and red (international response). Corresponding fatality thresholds for yellow, orange, and red alert levels are 1, 100, and 1,000, respectively. For damage impact, yellow, orange, and red thresholds are triggered by estimated losses reaching $1M, $100M, and $1B, respectively. The rationale for a dual approach to earthquake alerting stems from the recognition that relatively high fatalities, injuries, and homelessness predominate in countries in which local building practices typically lend themselves to high collapse and casualty rates, and these impacts lend to prioritization for international response. In contrast, financial and overall societal impacts often trigger the level of response in regions or countries in which prevalent earthquake resistant construction practices greatly reduce building collapse and resulting fatalities. Any newly devised alert, whether economic- or casualty-based, should be intuitive and consistent with established lexicons and procedures. Useful alerts should

  19. A post-Tohoku earthquake review of earthquake probabilities in the Southern Kanto District, Japan

    NASA Astrophysics Data System (ADS)

    Somerville, Paul G.

    2014-12-01

    The 2011 Mw 9.0 Tohoku earthquake generated an aftershock sequence that affected a large part of northern Honshu, and has given rise to widely divergent forecasts of changes in earthquake occurrence probabilities in northern Honshu. The objective of this review is to assess these forecasts as they relate to potential changes in the occurrence probabilities of damaging earthquakes in the Kanto Region. It is generally agreed that the 2011 Mw 9.0 Tohoku earthquake increased the stress on faults in the southern Kanto district. Toda and Stein (Geophys Res Lett 686, 40: doi:10.1002, 2013) further conclude that the probability of earthquakes in the Kanto Corridor has increased by a factor of 2.5 for the time period 11 March 2013 to 10 March 2018 in the Kanto Corridor. Estimates of earthquake probabilities in a wider region of the Southern Kanto District by Nanjo et al. (Geophys J Int, doi:10.1093, 2013) indicate that any increase in the probability of earthquakes is insignificant in this larger region. Uchida et al. (Earth Planet Sci Lett 374: 81-91, 2013) conclude that the Philippine Sea plate the extends well north of the northern margin of Tokyo Bay, inconsistent with the Kanto Fragment hypothesis of Toda et al. (Nat Geosci, 1:1-6,2008), which attributes deep earthquakes in this region, which they term the Kanto Corridor, to a broken fragment of the Pacific plate. The results of Uchida and Matsuzawa (J Geophys Res 115:B07309, 2013)support the conclusion that fault creep in southern Kanto may be slowly relaxing the stress increase caused by the Tohoku earthquake without causing more large earthquakes. Stress transfer calculations indicate a large stress transfer to the Off Boso Segment as a result of the 2011 Tohoku earthquake. However, Ozawa et al. (J Geophys Res 117:B07404, 2012) used onshore GPS measurements to infer large post-Tohoku creep on the plate interface in the Off-Boso region, and Uchida and Matsuzawa (ibid.) measured similar large creep off the Boso

  20. Statistical Modeling of Fire Occurrence Using Data from the Tōhoku, Japan Earthquake and Tsunami.

    PubMed

    Anderson, Dana; Davidson, Rachel A; Himoto, Keisuke; Scawthorn, Charles

    2016-02-01

    In this article, we develop statistical models to predict the number and geographic distribution of fires caused by earthquake ground motion and tsunami inundation in Japan. Using new, uniquely large, and consistent data sets from the 2011 Tōhoku earthquake and tsunami, we fitted three types of models-generalized linear models (GLMs), generalized additive models (GAMs), and boosted regression trees (BRTs). This is the first time the latter two have been used in this application. A simple conceptual framework guided identification of candidate covariates. Models were then compared based on their out-of-sample predictive power, goodness of fit to the data, ease of implementation, and relative importance of the framework concepts. For the ground motion data set, we recommend a Poisson GAM; for the tsunami data set, a negative binomial (NB) GLM or NB GAM. The best models generate out-of-sample predictions of the total number of ignitions in the region within one or two. Prefecture-level prediction errors average approximately three. All models demonstrate predictive power far superior to four from the literature that were also tested. A nonlinear relationship is apparent between ignitions and ground motion, so for GLMs, which assume a linear response-covariate relationship, instrumental intensity was the preferred ground motion covariate because it captures part of that nonlinearity. Measures of commercial exposure were preferred over measures of residential exposure for both ground motion and tsunami ignition models. This may vary in other regions, but nevertheless highlights the value of testing alternative measures for each concept. Models with the best predictive power included two or three covariates. © 2015 Society for Risk Analysis.

  1. Post-earthquake building safety inspection: Lessons from the Canterbury, New Zealand, earthquakes

    USGS Publications Warehouse

    Marshall, J.; Jaiswal, Kishor; Gould, N.; Turner, F.; Lizundia, B.; Barnes, J.

    2013-01-01

    The authors discuss some of the unique aspects and lessons of the New Zealand post-earthquake building safety inspection program that was implemented following the Canterbury earthquake sequence of 2010–2011. The post-event safety assessment program was one of the largest and longest programs undertaken in recent times anywhere in the world. The effort engaged hundreds of engineering professionals throughout the country, and also sought expertise from outside, to perform post-earthquake structural safety inspections of more than 100,000 buildings in the city of Christchurch and the surrounding suburbs. While the building safety inspection procedure implemented was analogous to the ATC 20 program in the United States, many modifications were proposed and implemented in order to assess the large number of buildings that were subjected to strong and variable shaking during a period of two years. This note discusses some of the key aspects of the post-earthquake building safety inspection program and summarizes important lessons that can improve future earthquake response.

  2. Habitual hot-spring bathing by a group of Japanese macaques (Macaca fuscata) in their natural habitat.

    PubMed

    Zhang, Peng; Watanabe, Kunio; Eishi, Tokida

    2007-12-01

    Japanese macaques (Macaca fuscata) in a free-ranging group in Jigokudani valley, Nagano prefecture, are known to bathe in a hot spring. We used scan sampling in a study aimed at elucidating the causal factors and possible social transmission of this behavior. From 1980-2003, 31% of a total 114 females in the group habitually bathed in the hot spring. The habit was more widespread in dominant matrilines than in subordinate matrilines. Infants whose mothers bathed were more likely to bathe than infants of mothers who did not bathe. The number of monkeys bathing was clearly influenced by ambient air temperature. More monkeys bathed in the hot spring in winter than in summer. The results support the thermoregulation hypothesis of hot-spring bathing. Bathing behavior varies among age and sex categories of monkeys, with adult females and juveniles bathing more often than adult males and subadults. We compared hot-spring bathing with other thermoregulatory behaviors in various primate populations. (c) 2007 Wiley-Liss, Inc.

  3. Educational Reform in Postwar Japan: A Case Study of the High School Entrance Examination in Chiba Prefecture.

    ERIC Educational Resources Information Center

    Berman, David M.

    In structure and in function, the Japanese high school entrance examination--as exemplified by data from Chiba prefecture in 1986--survives as a prewar hierarchical cultural pattern. Postwar American occupation reforms offered "democratic education" in the form of a single-track system with 9 years of compulsory schooling; such a system,…

  4. Do Earthquakes Shake Stock Markets?

    PubMed Central

    2015-01-01

    This paper examines how major earthquakes affected the returns and volatility of aggregate stock market indices in thirty-five financial markets over the last twenty years. Results show that global financial markets are resilient to shocks caused by earthquakes even if these are domestic. Our analysis reveals that, in a few instances, some macroeconomic variables and earthquake characteristics (gross domestic product per capita, trade openness, bilateral trade flows, earthquake magnitude, a tsunami indicator, distance to the epicenter, and number of fatalities) mediate the impact of earthquakes on stock market returns, resulting in a zero net effect. However, the influence of these variables is market-specific, indicating no systematic pattern across global capital markets. Results also demonstrate that stock market volatility is unaffected by earthquakes, except for Japan. PMID:26197482

  5. Continuing Megathrust Earthquake Potential in northern Chile after the 2014 Iquique Earthquake Sequence

    NASA Astrophysics Data System (ADS)

    Hayes, G. P.; Herman, M. W.; Barnhart, W. D.; Furlong, K. P.; Riquelme, S.; Benz, H.; Bergman, E.; Barrientos, S. E.; Earle, P. S.; Samsonov, S. V.

    2014-12-01

    The seismic gap theory, which identifies regions of elevated hazard based on a lack of recent seismicity in comparison to other portions of a fault, has successfully explained past earthquakes and is useful for qualitatively describing where future large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile, which until recently had not ruptured in a megathrust earthquake since a M~8.8 event in 1877. On April 1 2014, a M 8.2 earthquake occurred within this northern Chile seismic gap, offshore of the city of Iquique; the size and spatial extent of the rupture indicate it was not the earthquake that had been anticipated. Here, we present a rapid assessment of the seismotectonics of the March-April 2014 seismic sequence offshore northern Chile, including analyses of earthquake (fore- and aftershock) relocations, moment tensors, finite fault models, moment deficit calculations, and cumulative Coulomb stress transfer calculations over the duration of the sequence. This ensemble of information allows us to place the current sequence within the context of historic seismicity in the region, and to assess areas of remaining and/or elevated hazard. Our results indicate that while accumulated strain has been released for a portion of the northern Chile seismic gap, significant sections have not ruptured in almost 150 years. These observations suggest that large-to-great sized megathrust earthquakes will occur north and south of the 2014 Iquique sequence sooner than might be expected had the 2014 events ruptured the entire seismic gap.

  6. The Mw 7.7 Bhuj earthquake: Global lessons for earthquake hazard in intra-plate regions

    USGS Publications Warehouse

    Schweig, E.; Gomberg, J.; Petersen, M.; Ellis, M.; Bodin, P.; Mayrose, L.; Rastogi, B.K.

    2003-01-01

    The Mw 7.7 Bhuj earthquake occurred in the Kachchh District of the State of Gujarat, India on 26 January 2001, and was one of the most damaging intraplate earthquakes ever recorded. This earthquake is in many ways similar to the three great New Madrid earthquakes that occurred in the central United States in 1811-1812, An Indo-US team is studying the similarities and differences of these sequences in order to learn lessons for earthquake hazard in intraplate regions. Herein we present some preliminary conclusions from that study. Both the Kutch and New Madrid regions have rift type geotectonic setting. In both regions the strain rates are of the order of 10-9/yr and attenuation of seismic waves as inferred from observations of intensity and liquefaction are low. These strain rates predict recurrence intervals for Bhuj or New Madrid sized earthquakes of several thousand years or more. In contrast, intervals estimated from paleoseismic studies and from other independent data are significantly shorter, probably hundreds of years. All these observations together may suggest that earthquakes relax high ambient stresses that are locally concentrated by rheologic heterogeneities, rather than loading by plate-tectonic forces. The latter model generally underlies basic assumptions made in earthquake hazard assessment, that the long-term average rate of energy released by earthquakes is determined by the tectonic loading rate, which thus implies an inherent average periodicity of earthquake occurrence. Interpreting the observations in terms of the former model therefore may require re-examining the basic assumptions of hazard assessment.

  7. Earthquake precursors: spatial-temporal gravity changes before the great earthquakes in the Sichuan-Yunnan area

    NASA Astrophysics Data System (ADS)

    Zhu, Yi-Qing; Liang, Wei-Feng; Zhang, Song

    2018-01-01

    Using multiple-scale mobile gravity data in the Sichuan-Yunnan area, we systematically analyzed the relationships between spatial-temporal gravity changes and the 2014 Ludian, Yunnan Province Ms6.5 earthquake and the 2014 Kangding Ms6.3, 2013 Lushan Ms7.0, and 2008 Wenchuan Ms8.0 earthquakes in Sichuan Province. Our main results are as follows. (1) Before the occurrence of large earthquakes, gravity anomalies occur in a large area around the epicenters. The directions of gravity change gradient belts usually agree roughly with the directions of the main fault zones of the study area. Such gravity changes might reflect the increase of crustal stress, as well as the significant active tectonic movements and surface deformations along fault zones, during the period of gestation of great earthquakes. (2) Continuous significant changes of the multiple-scale gravity fields, as well as greater gravity changes with larger time scales, can be regarded as medium-range precursors of large earthquakes. The subsequent large earthquakes always occur in the area where the gravity changes greatly. (3) The spatial-temporal gravity changes are very useful in determining the epicenter of coming large earthquakes. The large gravity networks are useful to determine the general areas of coming large earthquakes. However, the local gravity networks with high spatial-temporal resolution are suitable for determining the location of epicenters. Therefore, denser gravity observation networks are necessary for better forecasts of the epicenters of large earthquakes. (4) Using gravity changes from mobile observation data, we made medium-range forecasts of the Kangding, Ludian, Lushan, and Wenchuan earthquakes, with especially successful forecasts of the location of their epicenters. Based on the above discussions, we emphasize that medium-/long-term potential for large earthquakes might exist nowadays in some areas with significant gravity anomalies in the study region. Thus, the monitoring

  8. Earthquakes in Mississippi and vicinity 1811-2010

    USGS Publications Warehouse

    Dart, Richard L.; Bograd, Michael B.E.

    2011-01-01

    This map summarizes two centuries of earthquake activity in Mississippi. Work on the Mississippi map was done in collaboration with the Mississippi Department of Environmental Quality, Office of Geology. The earthquake data plotted on the map are from several sources: the Mississippi Department of Environmental Quality, the Center for Earthquake Research and Information, the National Center for Earthquake Engineering Research, and the Arkansas Geological Survey. In addition to earthquake locations, other materials include seismic hazard and isoseismal maps and related text. Earthquakes are a legitimate concern in Mississippi and parts of adjacent States. Mississippi has undergone a number of felt earthquakes since 1811. At least two of these events caused property damage: a magnitude 4.7 earthquake in 1931, and a magnitude 4.3 earthquake in 1967. The map shows all historical and instrumentally located earthquakes in Mississippi and vicinity between 1811 and 2010. The largest historic earthquake in the vicinity of the State was an intensity XI event, on December 16, 1811; the first earthquake in the New Madrid sequence. This violent event and the earthquakes that followed caused considerable damage to the then sparsely settled region.

  9. A Trial for Earthquake Prediction by Precise Monitoring of Deep Ground Water Temperature

    NASA Astrophysics Data System (ADS)

    Nasuhara, Y.; Otsuki, K.; Yamauchi, T.

    2006-12-01

    A near future large earthquake is estimated to occur off Miyagi prefecture, northeast Japan within 20 years at a probability of about 80 %. In order to predict this earthquake, we have observed groundwater temperature in a borehole at Sendai city 100 km west of the asperity. This borehole penetrates the fault zone of NE-trending active reverse fault, Nagamachi-Rifu fault zone, at 820m depth. Our concept of the ground water observation is that fault zones are natural amplifier of crustal strain, and hence at 820m depth we set a very precise quartz temperature sensor with the resolution of 0.0002 deg. C. We confirmed our observation system to work normally by both the pumping up tests and the systematic temperature changes at different depths. Since the observation started on June 20 in 2004, we found mysterious intermittent temperature fluctuations of two types; one is of a period of 5-10 days and an amplitude of ca. 0.1 deg. C, and the other is of a period of 11-21 days and an amplitude of ca. 0.2 deg. C. Based on the examination using the product of Grashof number and Prantl number, natural convection of water can be occurred in the borehole. However, since these temperature fluctuations are observed only at the depth around 820 m, thus it is likely that they represent the hydrological natures proper to the Nagamachi-Rifu fault zone. It is noteworthy that the small temperature changes correlatable with earth tide are superposed on the long term and large amplitude fluctuations. The amplitude on the days of the full moon and new moon is ca. 0.001 deg. C. The bottoms of these temperature fluctuations always delay about 6 hours relative to peaks of earth tide. This is interpreted as that water in the borehole is sucked into the fault zone on which tensional normal stress acts on the days of the full moon and new moon. The amplitude of the crustal strain by earth tide was measured at ca. 2∗10^-8 strain near our observation site. High frequency temperature noise of

  10. Overestimation of the earthquake hazard along the Himalaya: constraints in bracketing of medieval earthquakes from paleoseismic studies

    NASA Astrophysics Data System (ADS)

    Arora, Shreya; Malik, Javed N.

    2017-12-01

    The Himalaya is one of the most seismically active regions of the world. The occurrence of several large magnitude earthquakes viz. 1905 Kangra earthquake (Mw 7.8), 1934 Bihar-Nepal earthquake (Mw 8.2), 1950 Assam earthquake (Mw 8.4), 2005 Kashmir (Mw 7.6), and 2015 Gorkha (Mw 7.8) are the testimony to ongoing tectonic activity. In the last few decades, tremendous efforts have been made along the Himalayan arc to understand the patterns of earthquake occurrences, size, extent, and return periods. Some of the large magnitude earthquakes produced surface rupture, while some remained blind. Furthermore, due to the incompleteness of the earthquake catalogue, a very few events can be correlated with medieval earthquakes. Based on the existing paleoseismic data certainly, there exists a complexity to precisely determine the extent of surface rupture of these earthquakes and also for those events, which occurred during historic times. In this paper, we have compiled the paleo-seismological data and recalibrated the radiocarbon ages from the trenches excavated by previous workers along the entire Himalaya and compared earthquake scenario with the past. Our studies suggest that there were multiple earthquake events with overlapping surface ruptures in small patches with an average rupture length of 300 km limiting Mw 7.8-8.0 for the Himalayan arc, rather than two or three giant earthquakes rupturing the whole front. It has been identified that the large magnitude Himalayan earthquakes, such as 1905 Kangra, 1934 Bihar-Nepal, and 1950 Assam, that have occurred within a time frame of 45 years. Now, if these events are dated, there is a high possibility that within the range of ±50 years, they may be considered as the remnant of one giant earthquake rupturing the entire Himalayan arc. Therefore, leading to an overestimation of seismic hazard scenario in Himalaya.

  11. Simulating Earthquake Early Warning Systems in the Classroom as a New Approach to Teaching Earthquakes

    NASA Astrophysics Data System (ADS)

    D'Alessio, M. A.

    2010-12-01

    A discussion of P- and S-waves seems an ubiquitous part of studying earthquakes in the classroom. Textbooks from middle school through university level typically define the differences between the waves and illustrate the sense of motion. While many students successfully memorize the differences between wave types (often utilizing the first letter as a memory aide), textbooks rarely give tangible examples of how the two waves would "feel" to a person sitting on the ground. One reason for introducing the wave types is to explain how to calculate earthquake epicenters using seismograms and travel time charts -- very abstract representations of earthquakes. Even when the skill is mastered using paper-and-pencil activities or one of the excellent online interactive versions, locating an epicenter simply does not excite many of our students because it evokes little emotional impact, even in students located in earthquake-prone areas. Despite these limitations, huge numbers of students are mandated to complete the task. At the K-12 level, California requires that all students be able to locate earthquake epicenters in Grade 6; in New York, the skill is a required part of the Regent's Examination. Recent innovations in earthquake early warning systems around the globe give us the opportunity to address the same content standard, but with substantially more emotional impact on students. I outline a lesson about earthquakes focused on earthquake early warning systems. The introductory activities include video clips of actual earthquakes and emphasize the differences between the way P- and S-waves feel when they arrive (P arrives first, but is weaker). I include an introduction to the principle behind earthquake early warning (including a summary of possible uses of a few seconds warning about strong shaking) and show examples from Japan. Students go outdoors to simulate P-waves, S-waves, and occupants of two different cities who are talking to one another on cell phones

  12. Demand surge following earthquakes

    USGS Publications Warehouse

    Olsen, Anna H.

    2012-01-01

    Demand surge is understood to be a socio-economic phenomenon where repair costs for the same damage are higher after large- versus small-scale natural disasters. It has reportedly increased monetary losses by 20 to 50%. In previous work, a model for the increased costs of reconstruction labor and materials was developed for hurricanes in the Southeast United States. The model showed that labor cost increases, rather than the material component, drove the total repair cost increases, and this finding could be extended to earthquakes. A study of past large-scale disasters suggested that there may be additional explanations for demand surge. Two such explanations specific to earthquakes are the exclusion of insurance coverage for earthquake damage and possible concurrent causation of damage from an earthquake followed by fire or tsunami. Additional research into these aspects might provide a better explanation for increased monetary losses after large- vs. small-scale earthquakes.

  13. Intermediate-term earthquake prediction

    USGS Publications Warehouse

    Knopoff, L.

    1990-01-01

    The problems in predicting earthquakes have been attacked by phenomenological methods from pre-historic times to the present. The associations of presumed precursors with large earthquakes often have been remarked upon. the difficulty in identifying whether such correlations are due to some chance coincidence or are real precursors is that usually one notes the associations only in the relatively short time intervals before the large events. Only rarely, if ever, is notice taken of whether the presumed precursor is to be found in the rather long intervals that follow large earthquakes, or in fact is absent in these post-earthquake intervals. If there are enough examples, the presumed correlation fails as a precursor in the former case, while in the latter case the precursor would be verified. Unfortunately, the observer is usually not concerned with the 'uniteresting' intervals that have no large earthquakes

  14. Earthquakes on Your Dinner Table

    NASA Astrophysics Data System (ADS)

    Alexeev, N. A.; Tape, C.; Alexeev, V. A.

    2016-12-01

    Earthquakes have interesting physics applicable to other phenomena like propagation of waves, also, they affect human lives. This study focused on three questions, how: depth, distance from epicenter and ground hardness affect earthquake strength. Experimental setup consisted of a gelatin slab to simulate crust. The slab was hit with a weight and earthquake amplitude was measured. It was found that earthquake amplitude was larger when the epicenter was deeper, which contradicts observations and probably was an artifact of the design. Earthquake strength was inversely proportional to the distance from the epicenter, which generally follows reality. Soft and medium jello were implanted into hard jello. It was found that earthquakes are stronger in softer jello, which was a result of resonant amplification in soft ground. Similar results are found in Minto Flats, where earthquakes are stronger and last longer than in the nearby hills. Earthquakes waveforms from Minto Flats showed that that the oscillations there have longer periods compared to the nearby hills with harder soil. Two gelatin pieces with identical shapes and different hardness were vibrated on a platform at varying frequencies in order to demonstrate that their resonant frequencies are statistically different. This phenomenon also occurs in Yukon Flats.

  15. Effective educational practice of river learning by using of Hiikawa-river of elementary school, Shimane prefecture, Japan

    NASA Astrophysics Data System (ADS)

    Tomoyuki, U.; Matsumoto, I.

    2012-12-01

    The importance of field learning has been increasing at elementary school and junior high school in Japan. However, In Japan, it is little actual situation that there is in an opportunity for the field learning enforced in the school science lesson. This tendency is strong as much as school of the city and that circumference. I think that this cause is that there are few suitable places for educational tool to observe geological field near the school. Children learn about "Function of running water" in Grade 5 of elementary school in Japan. Therefore, In this study, We remark the river called "Hiikawa-river" which flow in Izumo city, Shimane prefecture as the science teaching materials. Hiikawa is the river which flowing through the granitic rock district. Therefore We can observe granitic rock from in the upper stream, midstream, to the down stream. That is, we can observe the function of running water and diameter (size) of granitic boulders. It is mean that Hiikawa is the one of good educational tool for Children to learn the function of running water. Though it is the place where nature is comparatively rich even in Japan, it can't be said that field learning is relatively popular in Shimane prefecture. I think that teacher has to learning experience at field, because teacher should settle confidence to guide to the student at the field. That is, if it is not, you can not teach children with truly important of curriculum view point of natural and field science. In this research, we introduce practice of geological field learning at the public elementary school of the Shimane prefecture by using of Hiikawa as educational tool which children learn about the function of running water in grade 5, elementary school. In addition, we hope that this study contribute to teachers teaching method and to children natural science literacy.

  16. A remarkable new species of Nemoura (Plecoptera: Nemouridae) from Chuxiong Yi Autonomous Prefecture of Yunnan Province, China.

    PubMed

    Qian, Yu-Han; Xiao, Qian; Chen, Zhi-Teng; Du, Yu-Zhou

    2018-01-24

    A new species of the genus Nemoura, N. latilongispina sp. nov. from Chuxiong Yi Autonomous Prefecture of Yunnan Province, southwestern China is described and illustrated. The new species is characterized by ventral sclerite of epiproct extended laterally, forming upcurved plates fringed with long spines along upper margin, and by the strongly sclerotized, fork-shaped cercus.

  17. Damaging earthquakes: A scientific laboratory

    USGS Publications Warehouse

    Hays, Walter W.; ,

    1996-01-01

    This paper reviews the principal lessons learned from multidisciplinary postearthquake investigations of damaging earthquakes throughout the world during the past 15 years. The unique laboratory provided by a damaging earthquake in culturally different but tectonically similar regions of the world has increased fundamental understanding of earthquake processes, added perishable scientific, technical, and socioeconomic data to the knowledge base, and led to changes in public policies and professional practices for earthquake loss reduction.

  18. 2010 Chile Earthquake Aftershock Response

    NASA Astrophysics Data System (ADS)

    Barientos, Sergio

    2010-05-01

    The Mw=8.8 earthquake off the coast of Chile on 27 February 2010 is the 5th largest megathrust earthquake ever to be recorded and provides an unprecedented opportunity to advance our understanding of megathrust earthquakes and associated phenomena. The 2010 Chile earthquake ruptured the Concepcion-Constitucion segment of the Nazca/South America plate boundary, south of the Central Chile region and triggered a tsunami along the coast. Following the 2010 earthquake, a very energetic aftershock sequence is being observed in an area that is 600 km along strike from Valparaiso to 150 km south of Concepcion. Within the first three weeks there were over 260 aftershocks with magnitude 5.0 or greater and 18 with magnitude 6.0 or greater (NEIC, USGS). The Concepcion-Constitucion segment lies immediately north of the rupture zone associated with the great magnitude 9.5 Chile earthquake, and south of the 1906 and the 1985 Valparaiso earthquakes. The last great subduction earthquake in the region dates back to the February 1835 event described by Darwin (1871). Since 1835, part of the region was affected in the north by the Talca earthquake in December 1928, interpreted as a shallow dipping thrust event, and by the Chillan earthquake (Mw 7.9, January 1939), a slab-pull intermediate depth earthquake. For the last 30 years, geodetic studies in this area were consistent with a fully coupled elastic loading of the subduction interface at depth; this led to identify the area as a mature seismic gap with potential for an earthquake of magnitude of the order 8.5 or several earthquakes of lesser magnitude. What was less expected was the partial rupturing of the 1985 segment toward north. Today, the 2010 earthquake raises some disturbing questions: Why and how the rupture terminated where it did at the northern end? How did the 2010 earthquake load the adjacent segment to the north and did the 1985 earthquake only partially ruptured the plate interface leaving loaded asperities since

  19. Sensing the earthquake

    NASA Astrophysics Data System (ADS)

    Bichisao, Marta; Stallone, Angela

    2017-04-01

    Making science visual plays a crucial role in the process of building knowledge. In this view, art can considerably facilitate the representation of the scientific content, by offering a different perspective on how a specific problem could be approached. Here we explore the possibility of presenting the earthquake process through visual dance. From a choreographer's point of view, the focus is always on the dynamic relationships between moving objects. The observed spatial patterns (coincidences, repetitions, double and rhythmic configurations) suggest how objects organize themselves in the environment and what are the principles underlying that organization. The identified set of rules is then implemented as a basis for the creation of a complex rhythmic and visual dance system. Recently, scientists have turned seismic waves into sound and animations, introducing the possibility of "feeling" the earthquakes. We try to implement these results into a choreographic model with the aim to convert earthquake sound to a visual dance system, which could return a transmedia representation of the earthquake process. In particular, we focus on a possible method to translate and transfer the metric language of seismic sound and animations into body language. The objective is to involve the audience into a multisensory exploration of the earthquake phenomenon, through the stimulation of the hearing, eyesight and perception of the movements (neuromotor system). In essence, the main goal of this work is to develop a method for a simultaneous visual and auditory representation of a seismic event by means of a structured choreographic model. This artistic representation could provide an original entryway into the physics of earthquakes.

  20. Discrepancy between earthquake rates implied by historic earthquakes and a consensus geologic source model for California

    USGS Publications Warehouse

    Petersen, M.D.; Cramer, C.H.; Reichle, M.S.; Frankel, A.D.; Hanks, T.C.

    2000-01-01

    We examine the difference between expected earthquake rates inferred from the historical earthquake catalog and the geologic data that was used to develop the consensus seismic source characterization for the state of California [California Department of Conservation, Division of Mines and Geology (CDMG) and U.S. Geological Survey (USGS) Petersen et al., 1996; Frankel et al., 1996]. On average the historic earthquake catalog and the seismic source model both indicate about one M 6 or greater earthquake per year in the state of California. However, the overall earthquake rates of earthquakes with magnitudes (M) between 6 and 7 in this seismic source model are higher, by at least a factor of 2, than the mean historic earthquake rates for both southern and northern California. The earthquake rate discrepancy results from a seismic source model that includes earthquakes with characteristic (maximum) magnitudes that are primarily between M 6.4 and 7.1. Many of these faults are interpreted to accommodate high strain rates from geologic and geodetic data but have not ruptured in large earthquakes during historic time. Our sensitivity study indicates that the rate differences between magnitudes 6 and 7 can be reduced by adjusting the magnitude-frequency distribution of the source model to reflect more characteristic behavior, by decreasing the moment rate available for seismogenic slip along faults, by increasing the maximum magnitude of the earthquake on a fault, or by decreasing the maximum magnitude of the background seismicity. However, no single parameter can be adjusted, consistent with scientific consensus, to eliminate the earthquake rate discrepancy. Applying a combination of these parametric adjustments yields an alternative earthquake source model that is more compatible with the historic data. The 475-year return period hazard for peak ground and 1-sec spectral acceleration resulting from this alternative source model differs from the hazard resulting from the

  1. GPS Technologies as a Tool to Detect the Pre-Earthquake Signals Associated with Strong Earthquakes

    NASA Astrophysics Data System (ADS)

    Pulinets, S. A.; Krankowski, A.; Hernandez-Pajares, M.; Liu, J. Y. G.; Hattori, K.; Davidenko, D.; Ouzounov, D.

    2015-12-01

    The existence of ionospheric anomalies before earthquakes is now widely accepted. These phenomena started to be considered by GPS community to mitigate the GPS signal degradation over the territories of the earthquake preparation. The question is still open if they could be useful for seismology and for short-term earthquake forecast. More than decade of intensive studies proved that ionospheric anomalies registered before earthquakes are initiated by processes in the boundary layer of atmosphere over earthquake preparation zone and are induced in the ionosphere by electromagnetic coupling through the Global Electric Circuit. Multiparameter approach based on the Lithosphere-Atmosphere-Ionosphere Coupling model demonstrated that earthquake forecast is possible only if we consider the final stage of earthquake preparation in the multidimensional space where every dimension is one from many precursors in ensemble, and they are synergistically connected. We demonstrate approaches developed in different countries (Russia, Taiwan, Japan, Spain, and Poland) within the framework of the ISSI and ESA projects) to identify the ionospheric precursors. They are also useful to determine the all three parameters necessary for the earthquake forecast: impending earthquake epicenter position, expectation time and magnitude. These parameters are calculated using different technologies of GPS signal processing: time series, correlation, spectral analysis, ionospheric tomography, wave propagation, etc. Obtained results from different teams demonstrate the high level of statistical significance and physical justification what gives us reason to suggest these methodologies for practical validation.

  2. Earthquake Fingerprints: Representing Earthquake Waveforms for Similarity-Based Detection

    NASA Astrophysics Data System (ADS)

    Bergen, K.; Beroza, G. C.

    2016-12-01

    New earthquake detection methods, such as Fingerprint and Similarity Thresholding (FAST), use fast approximate similarity search to identify similar waveforms in long-duration data without templates (Yoon et al. 2015). These methods have two key components: fingerprint extraction and an efficient search algorithm. Fingerprint extraction converts waveforms into fingerprints, compact signatures that represent short-duration waveforms for identification and search. Earthquakes are detected using an efficient indexing and search scheme, such as locality-sensitive hashing, that identifies similar waveforms in a fingerprint database. The quality of the search results, and thus the earthquake detection results, is strongly dependent on the fingerprinting scheme. Fingerprint extraction should map similar earthquake waveforms to similar waveform fingerprints to ensure a high detection rate, even under additive noise and small distortions. Additionally, fingerprints corresponding to noise intervals should have mutually dissimilar fingerprints to minimize false detections. In this work, we compare the performance of multiple fingerprint extraction approaches for the earthquake waveform similarity search problem. We apply existing audio fingerprinting (used in content-based audio identification systems) and time series indexing techniques and present modified versions that are specifically adapted for seismic data. We also explore data-driven fingerprinting approaches that can take advantage of labeled or unlabeled waveform data. For each fingerprinting approach we measure its ability to identify similar waveforms in a low signal-to-noise setting, and quantify the trade-off between true and false detection rates in the presence of persistent noise sources. We compare the performance using known event waveforms from eight independent stations in the Northern California Seismic Network.

  3. Earthquake-related versus non-earthquake-related injuries in spinal injury patients: differentiation with multidetector computed tomography

    PubMed Central

    2010-01-01

    Introduction In recent years, several massive earthquakes have occurred across the globe. Multidetector computed tomography (MDCT) is reliable in detecting spinal injuries. The purpose of this study was to compare the features of spinal injuries resulting from the Sichuan earthquake with those of non-earthquake-related spinal trauma using MDCT. Methods Features of spinal injuries of 223 Sichuan earthquake-exposed patients and 223 non-earthquake-related spinal injury patients were retrospectively compared using MDCT. The date of non-earthquake-related spinal injury patients was collected from 1 May 2009 to 22 July 2009 to avoid the confounding effects of seasonal activity and clothing. We focused on anatomic sites, injury types and neurologic deficits related to spinal injuries. Major injuries were classified according to the grid 3-3-3 scheme of the Magerl (AO) classification system. Results A total of 185 patients (82.96%) in the earthquake-exposed cohort experienced crush injuries. In the earthquake and control groups, 65 and 92 patients, respectively, had neurologic deficits. The anatomic distribution of these two cohorts was significantly different (P < 0.001). Cervical spinal injuries were more common in the control group (risk ratio (RR) = 2.12, P < 0.001), whereas lumbar spinal injuries were more common in the earthquake-related spinal injuries group (277 of 501 injured vertebrae; 55.29%). The major types of injuries were significantly different between these cohorts (P = 0.002). Magerl AO type A lesions composed most of the lesions seen in both of these cohorts. Type B lesions were more frequently seen in earthquake-related spinal injuries (RR = 1.27), while we observed type C lesions more frequently in subjects with non-earthquake-related spinal injuries (RR = 1.98, P = 0.0029). Conclusions Spinal injuries sustained in the Sichuan earthquake were located mainly in the lumbar spine, with a peak prevalence of type A lesions and a high occurrence of

  4. Earthquake Emergency Education in Dushanbe, Tajikistan

    ERIC Educational Resources Information Center

    Mohadjer, Solmaz; Bendick, Rebecca; Halvorson, Sarah J.; Saydullaev, Umed; Hojiboev, Orifjon; Stickler, Christine; Adam, Zachary R.

    2010-01-01

    We developed a middle school earthquake science and hazards curriculum to promote earthquake awareness to students in the Central Asian country of Tajikistan. These materials include pre- and post-assessment activities, six science activities describing physical processes related to earthquakes, five activities on earthquake hazards and mitigation…

  5. Intensity earthquake scenario (scenario event - a damaging earthquake with higher probability of occurrence) for the city of Sofia

    NASA Astrophysics Data System (ADS)

    Aleksandrova, Irena; Simeonova, Stela; Solakov, Dimcho; Popova, Maria

    2014-05-01

    Among the many kinds of natural and man-made disasters, earthquakes dominate with regard to their social and economical impact on the urban environment. Global seismic risk to earthquakes are increasing steadily as urbanization and development occupy more areas that a prone to effects of strong earthquakes. Additionally, the uncontrolled growth of mega cities in highly seismic areas around the world is often associated with the construction of seismically unsafe buildings and infrastructures, and undertaken with an insufficient knowledge of the regional seismicity peculiarities and seismic hazard. The assessment of seismic hazard and generation of earthquake scenarios is the first link in the prevention chain and the first step in the evaluation of the seismic risk. The earthquake scenarios are intended as a basic input for developing detailed earthquake damage scenarios for the cities and can be used in earthquake-safe town and infrastructure planning. The city of Sofia is the capital of Bulgaria. It is situated in the centre of the Sofia area that is the most populated (the population is of more than 1.2 mil. inhabitants), industrial and cultural region of Bulgaria that faces considerable earthquake risk. The available historical documents prove the occurrence of destructive earthquakes during the 15th-18th centuries in the Sofia zone. In 19th century the city of Sofia has experienced two strong earthquakes: the 1818 earthquake with epicentral intensity I0=8-9 MSK and the 1858 earthquake with I0=9-10 MSK. During the 20th century the strongest event occurred in the vicinity of the city of Sofia is the 1917 earthquake with MS=5.3 (I0=7-8 MSK). Almost a century later (95 years) an earthquake of moment magnitude 5.6 (I0=7-8 MSK) hit the city of Sofia, on May 22nd, 2012. In the present study as a deterministic scenario event is considered a damaging earthquake with higher probability of occurrence that could affect the city with intensity less than or equal to VIII

  6. Earthquake recurrence models fail when earthquakes fail to reset the stress field

    USGS Publications Warehouse

    Tormann, Thessa; Wiemer, Stefan; Hardebeck, Jeanne L.

    2012-01-01

    Parkfield's regularly occurring M6 mainshocks, about every 25 years, have over two decades stoked seismologists' hopes to successfully predict an earthquake of significant size. However, with the longest known inter-event time of 38 years, the latest M6 in the series (28 Sep 2004) did not conform to any of the applied forecast models, questioning once more the predictability of earthquakes in general. Our study investigates the spatial pattern of b-values along the Parkfield segment through the seismic cycle and documents a stably stressed structure. The forecasted rate of M6 earthquakes based on Parkfield's microseismicity b-values corresponds well to observed rates. We interpret the observed b-value stability in terms of the evolution of the stress field in that area: the M6 Parkfield earthquakes do not fully unload the stress on the fault, explaining why time recurrent models fail. We present the 1989 M6.9 Loma Prieta earthquake as counter example, which did release a significant portion of the stress along its fault segment and yields a substantial change in b-values.

  7. The Virtual Quake Earthquake Simulator: Earthquake Probability Statistics for the El Mayor-Cucapah Region and Evidence of Predictability in Simulated Earthquake Sequences

    NASA Astrophysics Data System (ADS)

    Schultz, K.; Yoder, M. R.; Heien, E. M.; Rundle, J. B.; Turcotte, D. L.; Parker, J. W.; Donnellan, A.

    2015-12-01

    We introduce a framework for developing earthquake forecasts using Virtual Quake (VQ), the generalized successor to the perhaps better known Virtual California (VC) earthquake simulator. We discuss the basic merits and mechanics of the simulator, and we present several statistics of interest for earthquake forecasting. We also show that, though the system as a whole (in aggregate) behaves quite randomly, (simulated) earthquake sequences limited to specific fault sections exhibit measurable predictability in the form of increasing seismicity precursory to large m > 7 earthquakes. In order to quantify this, we develop an alert based forecasting metric similar to those presented in Keilis-Borok (2002); Molchan (1997), and show that it exhibits significant information gain compared to random forecasts. We also discuss the long standing question of activation vs quiescent type earthquake triggering. We show that VQ exhibits both behaviors separately for independent fault sections; some fault sections exhibit activation type triggering, while others are better characterized by quiescent type triggering. We discuss these aspects of VQ specifically with respect to faults in the Salton Basin and near the El Mayor-Cucapah region in southern California USA and northern Baja California Norte, Mexico.

  8. Earthquake Damage Assessment Using Objective Image Segmentation: A Case Study of 2010 Haiti Earthquake

    NASA Technical Reports Server (NTRS)

    Oommen, Thomas; Rebbapragada, Umaa; Cerminaro, Daniel

    2012-01-01

    In this study, we perform a case study on imagery from the Haiti earthquake that evaluates a novel object-based approach for characterizing earthquake induced surface effects of liquefaction against a traditional pixel based change technique. Our technique, which combines object-oriented change detection with discriminant/categorical functions, shows the power of distinguishing earthquake-induced surface effects from changes in buildings using the object properties concavity, convexity, orthogonality and rectangularity. Our results suggest that object-based analysis holds promise in automatically extracting earthquake-induced damages from high-resolution aerial/satellite imagery.

  9. Rupture, waves and earthquakes.

    PubMed

    Uenishi, Koji

    2017-01-01

    Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz. There are countless valuable research outcomes obtained through this kinematics-based approach, but "extraordinary" phenomena that are difficult to be explained by this conventional description have been found, for instance, on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake, and more detailed study on rupture and wave dynamics, namely, possible mechanical characteristics of (1) rupture development around seismic sources, (2) earthquake-induced structural failures and (3) wave interaction that connects rupture (1) and failures (2), would be indispensable.

  10. Rupture, waves and earthquakes

    PubMed Central

    UENISHI, Koji

    2017-01-01

    Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz. There are countless valuable research outcomes obtained through this kinematics-based approach, but “extraordinary” phenomena that are difficult to be explained by this conventional description have been found, for instance, on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake, and more detailed study on rupture and wave dynamics, namely, possible mechanical characteristics of (1) rupture development around seismic sources, (2) earthquake-induced structural failures and (3) wave interaction that connects rupture (1) and failures (2), would be indispensable. PMID:28077808

  11. The CATDAT damaging earthquakes database

    NASA Astrophysics Data System (ADS)

    Daniell, J. E.; Khazai, B.; Wenzel, F.; Vervaeck, A.

    2011-08-01

    The global CATDAT damaging earthquakes and secondary effects (tsunami, fire, landslides, liquefaction and fault rupture) database was developed to validate, remove discrepancies, and expand greatly upon existing global databases; and to better understand the trends in vulnerability, exposure, and possible future impacts of such historic earthquakes. Lack of consistency and errors in other earthquake loss databases frequently cited and used in analyses was a major shortcoming in the view of the authors which needed to be improved upon. Over 17 000 sources of information have been utilised, primarily in the last few years, to present data from over 12 200 damaging earthquakes historically, with over 7000 earthquakes since 1900 examined and validated before insertion into the database. Each validated earthquake includes seismological information, building damage, ranges of social losses to account for varying sources (deaths, injuries, homeless, and affected), and economic losses (direct, indirect, aid, and insured). Globally, a slightly increasing trend in economic damage due to earthquakes is not consistent with the greatly increasing exposure. The 1923 Great Kanto (214 billion USD damage; 2011 HNDECI-adjusted dollars) compared to the 2011 Tohoku (>300 billion USD at time of writing), 2008 Sichuan and 1995 Kobe earthquakes show the increasing concern for economic loss in urban areas as the trend should be expected to increase. Many economic and social loss values not reported in existing databases have been collected. Historical GDP (Gross Domestic Product), exchange rate, wage information, population, HDI (Human Development Index), and insurance information have been collected globally to form comparisons. This catalogue is the largest known cross-checked global historic damaging earthquake database and should have far-reaching consequences for earthquake loss estimation, socio-economic analysis, and the global reinsurance field.

  12. Bayesian historical earthquake relocation: an example from the 1909 Taipei earthquake

    USGS Publications Warehouse

    Minson, Sarah E.; Lee, William H.K.

    2014-01-01

    Locating earthquakes from the beginning of the modern instrumental period is complicated by the fact that there are few good-quality seismograms and what traveltimes do exist may be corrupted by both large phase-pick errors and clock errors. Here, we outline a Bayesian approach to simultaneous inference of not only the hypocentre location but also the clock errors at each station and the origin time of the earthquake. This methodology improves the solution for the source location and also provides an uncertainty analysis on all of the parameters included in the inversion. As an example, we applied this Bayesian approach to the well-studied 1909 Mw 7 Taipei earthquake. While our epicentre location and origin time for the 1909 Taipei earthquake are consistent with earlier studies, our focal depth is significantly shallower suggesting a higher seismic hazard to the populous Taipei metropolitan area than previously supposed.

  13. Comparison of aftershock sequences between 1975 Haicheng earthquake and 1976 Tangshan earthquake

    NASA Astrophysics Data System (ADS)

    Liu, B.

    2017-12-01

    The 1975 ML 7.3 Haicheng earthquake and the 1976 ML 7.8 Tangshan earthquake occurred in the same tectonic unit. There are significant differences in spatial-temporal distribution, number of aftershocks and time duration for the aftershock sequence followed by these two main shocks. As we all know, aftershocks could be triggered by the regional seismicity change derived from the main shock, which was caused by the Coulomb stress perturbation. Based on the rate- and state- dependent friction law, we quantitative estimated the possible aftershock time duration with a combination of seismicity data, and compared the results from different approaches. The results indicate that, aftershock time durations from the Tangshan main shock is several times of that form the Haicheng main shock. This can be explained by the significant relationship between aftershock time duration and earthquake nucleation history, normal stressand shear stress loading rateon the fault. In fact the obvious difference of earthquake nucleation history from these two main shocks is the foreshocks. 1975 Haicheng earthquake has clear and long foreshocks, while 1976 Tangshan earthquake did not have clear foreshocks. In that case, abundant foreshocks may mean a long and active nucleation process that may have changed (weakened) the rocks in the source regions, so they should have a shorter aftershock sequences for the reason that stress in weak rocks decay faster.

  14. Thoracic Injuries in earthquake-related versus non-earthquake-related trauma patients: differentiation via Multi-detector Computed Tomography.

    PubMed

    Dong, Zhi-Hui; Yang, Zhi-Gang; Chen, Tian-Wu; Chu, Zhi-Gang; Deng, Wen; Shao, Heng

    2011-01-01

    Massive earthquakes are harmful to humankind. This study of a historical cohort aimed to investigate the difference between earthquake-related crush thoracic traumas and thoracic traumas unrelated to earthquakes using a multi-detector Computed Tomography (CT). We retrospectively compared an earthquake-exposed cohort of 215 thoracic trauma crush victims of the Sichuan earthquake to a cohort of 215 non-earthquake-related thoracic trauma patients, focusing on the lesions and coexisting injuries to the thoracic cage and the pulmonary parenchyma and pleura using a multi-detector CT. The incidence of rib fracture was elevated in the earthquake-exposed cohort (143 vs. 66 patients in the non-earthquake-exposed cohort, Risk Ratio (RR) = 2.2; p<0.001). Among these patients, those with more than 3 fractured ribs (106/143 vs. 41/66 patients, RR=1.2; p<0.05) or flail chest (45/143 vs. 11/66 patients, RR=1.9; p<0.05) were more frequently seen in the earthquake cohort. Earthquake-related crush injuries more frequently resulted in bilateral rib fractures (66/143 vs. 18/66 patients, RR= 1.7; p<0.01). Additionally, the incidence of non-rib fracture was higher in the earthquake cohort (85 vs. 60 patients, RR= 1.4; p<0.01). Pulmonary parenchymal and pleural injuries were more frequently seen in earthquake-related crush injuries (117 vs. 80 patients, RR=1.5 for parenchymal and 146 vs. 74 patients, RR = 2.0 for pleural injuries; p<0.001). Non-rib fractures, pulmonary parenchymal and pleural injuries had significant positive correlation with rib fractures in these two cohorts. Thoracic crush traumas resulting from the earthquake were life threatening with a high incidence of bony thoracic fractures. The ribs were frequently involved in bilateral and severe types of fractures, which were accompanied by non-rib fractures, pulmonary parenchymal and pleural injuries.

  15. Earthquake hazards: a national threat

    USGS Publications Warehouse

    ,

    2006-01-01

    Earthquakes are one of the most costly natural hazards faced by the Nation, posing a significant risk to 75 million Americans in 39 States. The risks that earthquakes pose to society, including death, injury, and economic loss, can be greatly reduced by (1) better planning, construction, and mitigation practices before earthquakes happen, and (2) providing critical and timely information to improve response after they occur. As part of the multi-agency National Earthquake Hazards Reduction Program, the U.S. Geological Survey (USGS) has the lead Federal responsibility to provide notification of earthquakes in order to enhance public safety and to reduce losses through effective forecasts based on the best possible scientific information.

  16. Discussion of New Approaches to Medium-Short-Term Earthquake Forecast in Practice of The Earthquake Prediction in Yunnan

    NASA Astrophysics Data System (ADS)

    Hong, F.

    2017-12-01

    After retrospection of years of practice of the earthquake prediction in Yunnan area, it is widely considered that the fixed-point earthquake precursory anomalies mainly reflect the field information. The increase of amplitude and number of precursory anomalies could help to determine the original time of earthquakes, however it is difficult to obtain the spatial relevance between earthquakes and precursory anomalies, thus we can hardly predict the spatial locations of earthquakes using precursory anomalies. The past practices have shown that the seismic activities are superior to the precursory anomalies in predicting earthquakes locations, resulting from the increased seismicity were observed before 80% M=6.0 earthquakes in Yunnan area. While the mobile geomagnetic anomalies are turned out to be helpful in predicting earthquakes locations in recent year, for instance, the forecasted earthquakes occurring time and area derived form the 1-year-scale geomagnetic anomalies before the M6.5 Ludian earthquake in 2014 are shorter and smaller than which derived from the seismicity enhancement region. According to the past works, the author believes that the medium-short-term earthquake forecast level, as well as objective understanding of the seismogenic mechanisms, could be substantially improved by the densely laying observation array and capturing the dynamic process of physical property changes in the enhancement region of medium to small earthquakes.

  17. Earthquakes, May-June, 1992

    USGS Publications Warehouse

    Person, Waverly J.

    1992-01-01

    The months of May and June were very active in terms of earthquake occurrence. Six major earthquakes (7.0earthquakes included a magnitude 7.1 in Papua New Guinea on May 15, a magnitude 7.1 followed by a magnitude 7.5 in the Philippine Islands on May 17, a magnitude 7.0 in the Cuba region on May 25, and a magnitude 7.3 in the Santa Cruz Islands of the Pacific on May 27. In the United States, a magnitude 7.6 earthquake struck in southern California on June 28 followed by a magnitude 6.7 quake about three hours later.

  18. Normal Fault Type Earthquakes Off Fukushima Region - Comparison of the 1938 Events and Recent Earthquakes -

    NASA Astrophysics Data System (ADS)

    Murotani, S.; Satake, K.

    2017-12-01

    Off Fukushima region, Mjma 7.4 (event A) and 6.9 (event B) events occurred on November 6, 1938, following the thrust fault type earthquakes of Mjma 7.5 and 7.3 on the previous day. These earthquakes were estimated as normal fault earthquakes by Abe (1977, Tectonophysics). An Mjma 7.0 earthquake occurred on July 12, 2014 near event B and an Mjma 7.4 earthquake occurred on November 22, 2016 near event A. These recent events are the only M 7 class earthquakes occurred off Fukushima since 1938. Except for the two 1938 events, normal fault earthquakes have not occurred until many aftershocks of the 2011 Tohoku earthquake. We compared the observed tsunami and seismic waveforms of the 1938, 2014, and 2016 earthquakes to examine the normal fault earthquakes occurred off Fukushima region. It is difficult to compare the tsunami waveforms of the 1938, 2014 and 2016 events because there were only a few observations at the same station. The teleseismic body wave inversion of the 2016 earthquake yielded with the focal mechanism of strike 42°, dip 35°, and rake -94°. Other source parameters were as follows: source area 70 km x 40 km, average slip 0.2 m, maximum slip 1.2 m, seismic moment 2.2 x 1019 Nm, and Mw 6.8. A large slip area is located near the hypocenter, and it is compatible with the tsunami source area estimated from tsunami travel times. The 2016 tsunami source area is smaller than that of the 1938 event, consistent with the difference in Mw: 7.7 for event A estimated by Abe (1977) and 6.8 for the 2016 event. Although the 2014 epicenter is very close to that of event B, the teleseismic waveforms of the 2014 event are similar to those of event A and the 2016 event. While Abe (1977) assumed that the mechanism of event B was the same as event A, the initial motions at some stations are opposite, indicating that the focal mechanisms of events A and B are different and more detailed examination is needed. The normal fault type earthquake seems to occur following the

  19. What Can Sounds Tell Us About Earthquake Interactions?

    NASA Astrophysics Data System (ADS)

    Aiken, C.; Peng, Z.

    2012-12-01

    It is important not only for seismologists but also for educators to effectively convey information about earthquakes and the influences earthquakes can have on each other. Recent studies using auditory display [e.g. Kilb et al., 2012; Peng et al. 2012] have depicted catastrophic earthquakes and the effects large earthquakes can have on other parts of the world. Auditory display of earthquakes, which combines static images with time-compressed sound of recorded seismic data, is a new approach to disseminating information to a general audience about earthquakes and earthquake interactions. Earthquake interactions are influential to understanding the underlying physics of earthquakes and other seismic phenomena such as tremors in addition to their source characteristics (e.g. frequency contents, amplitudes). Earthquake interactions can include, for example, a large, shallow earthquake followed by increased seismicity around the mainshock rupture (i.e. aftershocks) or even a large earthquake triggering earthquakes or tremors several hundreds to thousands of kilometers away [Hill and Prejean, 2007; Peng and Gomberg, 2010]. We use standard tools like MATLAB, QuickTime Pro, and Python to produce animations that illustrate earthquake interactions. Our efforts are focused on producing animations that depict cross-section (side) views of tremors triggered along the San Andreas Fault by distant earthquakes, as well as map (bird's eye) views of mainshock-aftershock sequences such as the 2011/08/23 Mw5.8 Virginia earthquake sequence. These examples of earthquake interactions include sonifying earthquake and tremor catalogs as musical notes (e.g. piano keys) as well as audifying seismic data using time-compression. Our overall goal is to use auditory display to invigorate a general interest in earthquake seismology that leads to the understanding of how earthquakes occur, how earthquakes influence one another as well as tremors, and what the musical properties of these

  20. Earthquake Testing

    NASA Technical Reports Server (NTRS)

    1979-01-01

    During NASA's Apollo program, it was necessary to subject the mammoth Saturn V launch vehicle to extremely forceful vibrations to assure the moonbooster's structural integrity in flight. Marshall Space Flight Center assigned vibration testing to a contractor, the Scientific Services and Systems Group of Wyle Laboratories, Norco, California. Wyle-3S, as the group is known, built a large facility at Huntsville, Alabama, and equipped it with an enormously forceful shock and vibration system to simulate the liftoff stresses the Saturn V would encounter. Saturn V is no longer in service, but Wyle-3S has found spinoff utility for its vibration facility. It is now being used to simulate earthquake effects on various kinds of equipment, principally equipment intended for use in nuclear power generation. Government regulations require that such equipment demonstrate its ability to survive earthquake conditions. In upper left photo, Wyle3S is preparing to conduct an earthquake test on a 25ton diesel generator built by Atlas Polar Company, Ltd., Toronto, Canada, for emergency use in a Canadian nuclear power plant. Being readied for test in the lower left photo is a large circuit breaker to be used by Duke Power Company, Charlotte, North Carolina. Electro-hydraulic and electro-dynamic shakers in and around the pit simulate earthquake forces.

  1. Earthquakes in the United States

    USGS Publications Warehouse

    Stover, C.

    1977-01-01

    To supplement data in the report Preliminary Determination of Epicenters (PDE), the National earthquake Information Service (NEIS) also publishes a quarterly circular, Earthquakes in the United States. This provides information on the felt area of U.S earthquakes and their intensity. The main purpose is to describe the larger effects of these earthquakes so that they can be used in seismic risk studies, site evaluations for nuclear power plants, and answering inquiries by the general public.

  2. A smartphone application for earthquakes that matter!

    NASA Astrophysics Data System (ADS)

    Bossu, Rémy; Etivant, Caroline; Roussel, Fréderic; Mazet-Roux, Gilles; Steed, Robert

    2014-05-01

    Smartphone applications have swiftly become one of the most popular tools for rapid reception of earthquake information for the public, some of them having been downloaded more than 1 million times! The advantages are obvious: wherever someone's own location is, they can be automatically informed when an earthquake has struck. Just by setting a magnitude threshold and an area of interest, there is no longer the need to browse the internet as the information reaches you automatically and instantaneously! One question remains: are the provided earthquake notifications always relevant for the public? What are the earthquakes that really matters to laypeople? One clue may be derived from some newspaper reports that show that a while after damaging earthquakes many eyewitnesses scrap the application they installed just after the mainshock. Why? Because either the magnitude threshold is set too high and many felt earthquakes are missed, or it is set too low and the majority of the notifications are related to unfelt earthquakes thereby only increasing anxiety among the population at each new update. Felt and damaging earthquakes are the ones that matter the most for the public (and authorities). They are the ones of societal importance even when of small magnitude. A smartphone application developed by EMSC (Euro-Med Seismological Centre) with the financial support of the Fondation MAIF aims at providing suitable notifications for earthquakes by collating different information threads covering tsunamigenic, potentially damaging and felt earthquakes. Tsunamigenic earthquakes are considered here to be those ones that are the subject of alert or information messages from the PTWC (Pacific Tsunami Warning Centre). While potentially damaging earthquakes are identified through an automated system called EQIA (Earthquake Qualitative Impact Assessment) developed and operated at EMSC. This rapidly assesses earthquake impact by comparing the population exposed to each expected

  3. Analysis of Changes in Traumatic Symptoms and Daily Life Activity of Children Affected by the 2011 Japan Earthquake and Tsunami over Time

    PubMed Central

    Usami, Masahide; Iwadare, Yoshitaka; Watanabe, Kyota; Kodaira, Masaki; Ushijima, Hirokage; Tanaka, Tetsuya; Harada, Maiko; Tanaka, Hiromi; Sasaki, Yoshinori; Saito, Kazuhiko

    2014-01-01

    Background On March 11, 2011, Japan was struck by a massive earthquake and tsunami. The tsunami caused tremendous damage and traumatized a number of people, including children. This study aimed to compare traumatic symptoms and daily life activity among children 20 months after the 2011 Great East Japan Earthquake and Tsunami with those observed after 8 months. Methods The study comprised two groups. The first comprised 12,524 kindergarten, elementary school, and junior high school children in Ishinomaki City, Miyagi Prefecture, Japan, who were evaluated 8 months after the disaster. The second comprised 10,597 children from the same place who were evaluated 20 months after the disaster. The Post Traumatic Stress Symptoms for Children 15 items (PTSSC-15), a self-completion questionnaire on traumatic symptoms, and a questionnaire on children's daily life were distributed to the children. An effective response was obtained from 11,639 (92.9%, 8 months after) and 10,597 (86.9%, 20 months after) children. Results The PTSSC-15 score was significantly higher in junior high school girls than in boys. The PTSSC-15 score was significantly higher in 4th–6th grade girls than in boys after 8 months. Elementary and junior high school children evaluated after 20 months had a significantly lower PTSSC-15 score than those evaluated after 8 months. The number of children having breakfast was significantly higher after 8 months than that after 20 months. In both the groups, children of all grades who had breakfast had a significantly lower PTSSC-15 score than those who did not have breakfast. Conclusions We conclude that traumatic symptoms and daily life activity of children who survived the earthquake and tsunami improved over time. PMID:24586427

  4. Nowcasting Earthquakes and Tsunamis

    NASA Astrophysics Data System (ADS)

    Rundle, J. B.; Turcotte, D. L.

    2017-12-01

    The term "nowcasting" refers to the estimation of the current uncertain state of a dynamical system, whereas "forecasting" is a calculation of probabilities of future state(s). Nowcasting is a term that originated in economics and finance, referring to the process of determining the uncertain state of the economy or market indicators such as GDP at the current time by indirect means. We have applied this idea to seismically active regions, where the goal is to determine the current state of a system of faults, and its current level of progress through the earthquake cycle (http://onlinelibrary.wiley.com/doi/10.1002/2016EA000185/full). Advantages of our nowcasting method over forecasting models include: 1) Nowcasting is simply data analysis and does not involve a model having parameters that must be fit to data; 2) We use only earthquake catalog data which generally has known errors and characteristics; and 3) We use area-based analysis rather than fault-based analysis, meaning that the methods work equally well on land and in subduction zones. To use the nowcast method to estimate how far the fault system has progressed through the "cycle" of large recurring earthquakes, we use the global catalog of earthquakes, using "small" earthquakes to determine the level of hazard from "large" earthquakes in the region. We select a "small" region in which the nowcast is to be made, and compute the statistics of a much larger region around the small region. The statistics of the large region are then applied to the small region. For an application, we can define a small region around major global cities, for example a "small" circle of radius 150 km and a depth of 100 km, as well as a "large" earthquake magnitude, for example M6.0. The region of influence of such earthquakes is roughly 150 km radius x 100 km depth, which is the reason these values were selected. We can then compute and rank the seismic risk of the world's major cities in terms of their relative seismic risk

  5. Introduction to the special issue on the 2004 Parkfield earthquake and the Parkfield earthquake prediction experiment

    USGS Publications Warehouse

    Harris, R.A.; Arrowsmith, J.R.

    2006-01-01

    The 28 September 2004 M 6.0 Parkfield earthquake, a long-anticipated event on the San Andreas fault, is the world's best recorded earthquake to date, with state-of-the-art data obtained from geologic, geodetic, seismic, magnetic, and electrical field networks. This has allowed the preearthquake and postearthquake states of the San Andreas fault in this region to be analyzed in detail. Analyses of these data provide views into the San Andreas fault that show a complex geologic history, fault geometry, rheology, and response of the nearby region to the earthquake-induced ground movement. Although aspects of San Andreas fault zone behavior in the Parkfield region can be modeled simply over geological time frames, the Parkfield Earthquake Prediction Experiment and the 2004 Parkfield earthquake indicate that predicting the fine details of future earthquakes is still a challenge. Instead of a deterministic approach, forecasting future damaging behavior, such as that caused by strong ground motions, will likely continue to require probabilistic methods. However, the Parkfield Earthquake Prediction Experiment and the 2004 Parkfield earthquake have provided ample data to understand most of what did occur in 2004, culminating in significant scientific advances.

  6. Japanese earthquake predictability experiment with multiple runs before and after the 2011 Tohoku-oki earthquake

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Tsuruoka, H.; Yokoi, S.

    2011-12-01

    The current Japanese national earthquake prediction program emphasizes the importance of modeling as well as monitoring for a sound scientific development of earthquake prediction research. One major focus of the current program is to move toward creating testable earthquake forecast models. For this purpose, in 2009 we joined the Collaboratory for the Study of Earthquake Predictability (CSEP) and installed, through an international collaboration, the CSEP Testing Centre, an infrastructure to encourage researchers to develop testable models for Japan. We started Japanese earthquake predictability experiment on November 1, 2009. The experiment consists of 12 categories, with 4 testing classes with different time spans (1 day, 3 months, 1 year and 3 years) and 3 testing regions called 'All Japan,' 'Mainland,' and 'Kanto.' A total of 160 models, as of August 2013, were submitted, and are currently under the CSEP official suite of tests for evaluating the performance of forecasts. We will present results of prospective forecast and testing for periods before and after the 2011 Tohoku-oki earthquake. Because a seismic activity has changed dramatically since the 2011 event, performances of models have been affected very much. In addition, as there is the problem of authorized catalogue related to the completeness magnitude, most models did not pass the CSEP consistency tests. Also, we will discuss the retrospective earthquake forecast experiments for aftershocks of the 2011 Tohoku-oki earthquake. Our aim is to describe what has turned out to be the first occasion for setting up a research environment for rigorous earthquake forecasting in Japan.

  7. Japanese earthquake predictability experiment with multiple runs before and after the 2011 Tohoku-oki earthquake

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Tsuruoka, H.; Yokoi, S.

    2013-12-01

    The current Japanese national earthquake prediction program emphasizes the importance of modeling as well as monitoring for a sound scientific development of earthquake prediction research. One major focus of the current program is to move toward creating testable earthquake forecast models. For this purpose, in 2009 we joined the Collaboratory for the Study of Earthquake Predictability (CSEP) and installed, through an international collaboration, the CSEP Testing Centre, an infrastructure to encourage researchers to develop testable models for Japan. We started Japanese earthquake predictability experiment on November 1, 2009. The experiment consists of 12 categories, with 4 testing classes with different time spans (1 day, 3 months, 1 year and 3 years) and 3 testing regions called 'All Japan,' 'Mainland,' and 'Kanto.' A total of 160 models, as of August 2013, were submitted, and are currently under the CSEP official suite of tests for evaluating the performance of forecasts. We will present results of prospective forecast and testing for periods before and after the 2011 Tohoku-oki earthquake. Because a seismic activity has changed dramatically since the 2011 event, performances of models have been affected very much. In addition, as there is the problem of authorized catalogue related to the completeness magnitude, most models did not pass the CSEP consistency tests. Also, we will discuss the retrospective earthquake forecast experiments for aftershocks of the 2011 Tohoku-oki earthquake. Our aim is to describe what has turned out to be the first occasion for setting up a research environment for rigorous earthquake forecasting in Japan.

  8. Seismicity map tools for earthquake studies

    NASA Astrophysics Data System (ADS)

    Boucouvalas, Anthony; Kaskebes, Athanasios; Tselikas, Nikos

    2014-05-01

    We report on the development of new and online set of tools for use within Google Maps, for earthquake research. We demonstrate this server based and online platform (developped with PHP, Javascript, MySQL) with the new tools using a database system with earthquake data. The platform allows us to carry out statistical and deterministic analysis on earthquake data use of Google Maps and plot various seismicity graphs. The tool box has been extended to draw on the map line segments, multiple straight lines horizontally and vertically as well as multiple circles, including geodesic lines. The application is demonstrated using localized seismic data from the geographic region of Greece as well as other global earthquake data. The application also offers regional segmentation (NxN) which allows the studying earthquake clustering, and earthquake cluster shift within the segments in space. The platform offers many filters such for plotting selected magnitude ranges or time periods. The plotting facility allows statistically based plots such as cumulative earthquake magnitude plots and earthquake magnitude histograms, calculation of 'b' etc. What is novel for the platform is the additional deterministic tools. Using the newly developed horizontal and vertical line and circle tools we have studied the spatial distribution trends of many earthquakes and we here show for the first time the link between Fibonacci Numbers and spatiotemporal location of some earthquakes. The new tools are valuable for examining visualizing trends in earthquake research as it allows calculation of statistics as well as deterministic precursors. We plan to show many new results based on our newly developed platform.

  9. Earthquakes, November-December 1991

    USGS Publications Warehouse

    Person, W.J.

    1992-01-01

    There were three major earthquakes (7.0-7.9) during the last two months of the year: a magntidue 7.0 on November 19 in Columbia, a magnitude 7.4 in the Kuril Islands on December 22, and a magnitude 7.1 in the South Sandwich Islands on December 27. Earthquake-related deaths were reported in Colombia, Yemen, and Iran. there were no significant earthquakes in the United States during this reporting period. 

  10. Earthquakes, September-October 1980

    USGS Publications Warehouse

    Person, W.J.

    1981-01-01

    There were two major (magnitudes 7.0-7.9) earthquakes during this reporting period; a magnitude (M) 7.3 in Algeria where many people were killed or injured and extensive damage occurred, and an M=7.2 in the Loyalty Islands region of the South Pacific. Japan was struck by a damaging earthquake on September 24, killing two people and causing injuries. There were no damaging earthquakes in the United States. 

  11. Retrospective stress-forecasting of earthquakes

    NASA Astrophysics Data System (ADS)

    Gao, Yuan; Crampin, Stuart

    2015-04-01

    Observations of changes in azimuthally varying shear-wave splitting (SWS) above swarms of small earthquakes monitor stress-induced changes to the stress-aligned vertical microcracks pervading the upper crust, lower crust, and uppermost ~400km of the mantle. (The microcracks are intergranular films of hydrolysed melt in the mantle.) Earthquakes release stress, and an appropriate amount of stress for the relevant magnitude must accumulate before each event. Iceland is on an extension of the Mid-Atlantic Ridge, where two transform zones, uniquely run onshore. These onshore transform zones provide semi-continuous swarms of small earthquakes, which are the only place worldwide where SWS can be routinely monitored. Elsewhere SWS must be monitored above temporally-active occasional swarms of small earthquakes, or in infrequent SKS and other teleseismic reflections from the mantle. Observations of changes in SWS time-delays are attributed to stress-induced changes in crack aspect-ratios allowing stress-accumulation and stress-relaxation to be identified. Monitoring SWS in SW Iceland in 1988, stress-accumulation before an impending earthquake was recognised and emails were exchanged between the University of Edinburgh (EU) and the Iceland Meteorological Office (IMO). On 10th November 1988, EU emailed IMO that a M5 earthquake could occur soon on a seismically-active fault plane where seismicity was still continuing following a M5.1 earthquake six-months earlier. Three-days later, IMO emailed EU that a M5 earthquake had just occurred on the specified fault-plane. We suggest this is a successful earthquake stress-forecast, where we refer to the procedure as stress-forecasting earthquakes as opposed to predicting or forecasting to emphasise the different formalism. Lack of funds has prevented us monitoring SWS on Iceland seismograms, however, we have identified similar characteristic behaviour of SWS time-delays above swarms of small earthquakes which have enabled us to

  12. Earthquake watch

    USGS Publications Warehouse

    Hill, M.

    1976-01-01

     When the time comes that earthquakes can be predicted accurately, what shall we do with the knowledge? This was the theme of a November 1975 conference on earthquake warning and response held in San Francisco called by Assistant Secretary of the Interior Jack W. Carlson. Invited were officials of State and local governments from Alaska, California, Hawaii, Idaho, Montana, Nevada, utah, Washington, and Wyoming and representatives of the news media. 

  13. Charles Darwin's earthquake reports

    NASA Astrophysics Data System (ADS)

    Galiev, Shamil

    2010-05-01

    As it is the 200th anniversary of Darwin's birth, 2009 has also been marked as 170 years since the publication of his book Journal of Researches. During the voyage Darwin landed at Valdivia and Concepcion, Chile, just before, during, and after a great earthquake, which demolished hundreds of buildings, killing and injuring many people. Land was waved, lifted, and cracked, volcanoes awoke and giant ocean waves attacked the coast. Darwin was the first geologist to observe and describe the effects of the great earthquake during and immediately after. These effects sometimes repeated during severe earthquakes; but great earthquakes, like Chile 1835, and giant earthquakes, like Chile 1960, are rare and remain completely unpredictable. This is one of the few areas of science, where experts remain largely in the dark. Darwin suggested that the effects were a result of ‘ …the rending of strata, at a point not very deep below the surface of the earth…' and ‘…when the crust yields to the tension, caused by its gradual elevation, there is a jar at the moment of rupture, and a greater movement...'. Darwin formulated big ideas about the earth evolution and its dynamics. These ideas set the tone for the tectonic plate theory to come. However, the plate tectonics does not completely explain why earthquakes occur within plates. Darwin emphasised that there are different kinds of earthquakes ‘...I confine the foregoing observations to the earthquakes on the coast of South America, or to similar ones, which seem generally to have been accompanied by elevation of the land. But, as we know that subsidence has gone on in other quarters of the world, fissures must there have been formed, and therefore earthquakes...' (we cite the Darwin's sentences following researchspace. auckland. ac. nz/handle/2292/4474). These thoughts agree with results of the last publications (see Nature 461, 870-872; 636-639 and 462, 42-43; 87-89). About 200 years ago Darwin gave oneself airs by the

  14. Focal mechanisms of earthquakes in Mongolia

    NASA Astrophysics Data System (ADS)

    Sodnomsambuu, D.; Natalia, R.; Gangaadorj, B.; Munkhuu, U.; Davaasuren, G.; Danzansan, E.; Yan, R.; Valentina, M.; Battsetseg, B.

    2011-12-01

    Focal mechanism data provide information on the relative magnitudes of the principal stresses, so that a tectonic regime can be assigned. Especially such information is useful for the study of intraplate seismic active regions. A study of earthquake focal mechanisms in the territory of Mongolia as landlocked and intraplate region was conducted. We present map of focal mechanisms of earthquakes with M4.5 which occurred in Mongolia and neighboring regions. Focal mechanisms solutions were constrained by the first motion solutions, as well as by waveform modeling, particularly CMT solutions. Four earthquakes have been recorded in Mongolia in XX century with magnitude more than 8, the 1905 M7.9 Tsetserleg and M8.4 Bolnai earthquakes, the 1931 M8.0 Fu Yun earthquake, the 1957 M8.1 Gobi-Altai earthquake. However the map of focal mechanisms of earthquakes in Mongolia allows seeing all seismic active structures: Gobi Altay, Mongolian Altay, active fringe of Hangay dome, Hentii range etc. Earthquakes in the most of Mongolian territory and neighboring China regions are characterized by strike-slip and reverse movements. Strike-slip movements also are typical for earthquakes in Altay Range in Russia. The north of Mongolia and south part of the Baikal area is a region where have been occurred earthquakes with different focal mechanisms. This region is a zone of the transition between compressive regime associated to India-Eurasian collision and extensive structures localized in north of the country as Huvsgul area and Baykal rift. Earthquakes in the Baikal basin itself are characterized by normal movements. Earthquakes in Trans-Baikal zone and NW of Mongolia are characterized dominantly by strike-slip movements. Analysis of stress-axis orientations, the tectonic stress tensor is presented. The map of focal mechanisms of earthquakes in Mongolia could be useful tool for researchers in their study on Geodynamics of Central Asia, particularly of Mongolian and Baikal regions.

  15. Earthquakes and emergence

    NASA Astrophysics Data System (ADS)

    Earthquakes and emerging infections may not have a direct cause and effect relationship like tax evasion and jail, but new evidence suggests that there may be a link between the two human health hazards. Various media accounts have cited a massive 1993 earthquake in Maharashtra as a potential catalyst of the recent outbreak of plague in India that has claimed more than 50 lives and alarmed the world. The hypothesis is that the earthquake may have uprooted underground rat populations that carry the fleas infected with the bacterium that causes bubonic plague and can lead to the pneumonic form of the disease that is spread through the air.

  16. Earthquake predictions using seismic velocity ratios

    USGS Publications Warehouse

    Sherburne, R. W.

    1979-01-01

    Since the beginning of modern seismology, seismologists have contemplated predicting earthquakes. The usefulness of earthquake predictions to the reduction of human and economic losses and the value of long-range earthquake prediction to planning is obvious. Not as clear are the long-range economic and social impacts of earthquake prediction to a speicifc area. The general consensus of opinion among scientists and government officials, however, is that the quest of earthquake prediction is a worthwhile goal and should be prusued with a sense of urgency. 

  17. Earthquakes and Schools

    ERIC Educational Resources Information Center

    National Clearinghouse for Educational Facilities, 2008

    2008-01-01

    Earthquakes are low-probability, high-consequence events. Though they may occur only once in the life of a school, they can have devastating, irreversible consequences. Moderate earthquakes can cause serious damage to building contents and non-structural building systems, serious injury to students and staff, and disruption of building operations.…

  18. Is there a basis for preferring characteristic earthquakes over a Gutenberg–Richter distribution in probabilistic earthquake forecasting?

    USGS Publications Warehouse

    Parsons, Thomas E.; Geist, Eric L.

    2009-01-01

    The idea that faults rupture in repeated, characteristic earthquakes is central to most probabilistic earthquake forecasts. The concept is elegant in its simplicity, and if the same event has repeated itself multiple times in the past, we might anticipate the next. In practice however, assembling a fault-segmented characteristic earthquake rupture model can grow into a complex task laden with unquantified uncertainty. We weigh the evidence that supports characteristic earthquakes against a potentially simpler model made from extrapolation of a Gutenberg–Richter magnitude-frequency law to individual fault zones. We find that the Gutenberg–Richter model satisfies key data constraints used for earthquake forecasting equally well as a characteristic model. Therefore, judicious use of instrumental and historical earthquake catalogs enables large-earthquake-rate calculations with quantifiable uncertainty that should get at least equal weighting in probabilistic forecasting.

  19. Smoking prevalence increases following Canterbury earthquakes.

    PubMed

    Erskine, Nick; Daley, Vivien; Stevenson, Sue; Rhodes, Bronwen; Beckert, Lutz

    2013-01-01

    A magnitude 7.1 earthquake hit Canterbury in September 2010. This earthquake and associated aftershocks took the lives of 185 people and drastically changed residents' living, working, and social conditions. To explore the impact of the earthquakes on smoking status and levels of tobacco consumption in the residents of Christchurch. Semistructured interviews were carried out in two city malls and the central bus exchange 15 months after the first earthquake. A total of 1001 people were interviewed. In August 2010, prior to any earthquake, 409 (41%) participants had never smoked, 273 (27%) were currently smoking, and 316 (32%) were ex-smokers. Since the September 2010 earthquake, 76 (24%) of the 316 ex-smokers had smoked at least one cigarette and 29 (38.2%) had smoked more than 100 cigarettes. Of the 273 participants who were current smokers in August 2010, 93 (34.1%) had increased consumption following the earthquake, 94 (34.4%) had not changed, and 86 (31.5%) had decreased their consumption. 53 (57%) of the 93 people whose consumption increased reported that the earthquake and subsequent lifestyle changes as a reason to increase smoking. 24% of ex-smokers resumed smoking following the earthquake, resulting in increased smoking prevalence. Tobacco consumption levels increased in around one-third of current smokers.

  20. Defining "Acceptable Risk" for Earthquakes Worldwide

    NASA Astrophysics Data System (ADS)

    Tucker, B.

    2001-05-01

    The greatest and most rapidly growing earthquake risk for mortality is in developing countries. Further, earthquake risk management actions of the last 50 years have reduced the average lethality of earthquakes in earthquake-threatened industrialized countries. (This is separate from the trend of the increasing fiscal cost of earthquakes there.) Despite these clear trends, every new earthquake in developing countries is described in the media as a "wake up" call, announcing the risk these countries face. GeoHazards International (GHI) works at both the community and the policy levels to try to reduce earthquake risk. GHI reduces death and injury by helping vulnerable communities recognize their risk and the methods to manage it, by raising awareness of its risk, building local institutions to manage that risk, and strengthening schools to protect and train the community's future generations. At the policy level, GHI, in collaboration with research partners, is examining whether "acceptance" of these large risks by people in these countries and by international aid and development organizations explains the lack of activity in reducing these risks. The goal of this pilot project - The Global Earthquake Safety Initiative (GESI) - is to develop and evaluate a means of measuring the risk and the effectiveness of risk mitigation actions in the world's largest, most vulnerable cities: in short, to develop an earthquake risk index. One application of this index is to compare the risk and the risk mitigation effort of "comparable" cities. By this means, Lima, for example, can compare the risk of its citizens dying due to earthquakes with the risk of citizens in Santiago and Guayaquil. The authorities of Delhi and Islamabad can compare the relative risk from earthquakes of their school children. This index can be used to measure the effectiveness of alternate mitigation projects, to set goals for mitigation projects, and to plot progress meeting those goals. The preliminary

  1. Cyclic migration of weak earthquakes between Lunigiana earthquake of October 10, 1995 and Reggio Emilia earthquake of October 15, 1996 (Northern Italy)

    NASA Astrophysics Data System (ADS)

    di Giovambattista, R.; Tyupkin, Yu

    The cyclic migration of weak earthquakes (M 2.2) which occurred during the yearprior to the October 15, 1996 (M = 4.9) Reggio Emilia earthquake isdiscussed in this paper. The onset of this migration was associated with theoccurrence of the October 10, 1995 (M = 4.8) Lunigiana earthquakeabout 90 km southwest from the epicenter of the Reggio Emiliaearthquake. At least three series of earthquakes migrating from theepicentral area of the Lunigiana earthquake in the northeast direction wereobserved. The migration of earthquakes of the first series terminated at adistance of about 30 km from the epicenter of the Reggio Emiliaearthquake. The earthquake migration of the other two series halted atabout 10 km from the Reggio Emilia epicenter. The average rate ofearthquake migration was about 200-300 km/year, while the time ofrecurrence of the observed cycles varied from 68 to 178 days. Weakearthquakes migrated along the transversal fault zones and sometimesjumped from one fault to another. A correlation between the migratingearthquakes and tidal variations is analysed. We discuss the hypothesis thatthe analyzed area is in a state of stress approaching the limit of thelong-term durability of crustal rocks and that the observed cyclic migrationis a result of a combination of a more or less regular evolution of tectonicand tidal variations.

  2. The 2012 Mw5.6 earthquake in Sofia seismogenic zone - is it a slow earthquake

    NASA Astrophysics Data System (ADS)

    Raykova, Plamena; Solakov, Dimcho; Slavcheva, Krasimira; Simeonova, Stela; Aleksandrova, Irena

    2017-04-01

    Recently our understanding of tectonic faulting has been shaken by the discoveries of seismic tremor, low frequency earthquakes, slow slip events, and other models of fault slip. These phenomenas represent models of failure that were thought to be non-existent and theoretically impossible only a few years ago. Slow earthquakes are seismic phenomena in which the rupture of geological faults in the earth's crust occurs gradually without creating strong tremors. Despite the growing number of observations of slow earthquakes their origin remains unresolved. Studies show that the duration of slow earthquakes ranges from a few seconds to a few hundred seconds. The regular earthquakes with which most people are familiar release a burst of built-up stress in seconds, slow earthquakes release energy in ways that do little damage. This study focus on the characteristics of the Mw5.6 earthquake occurred in Sofia seismic zone on May 22nd, 2012. The Sofia area is the most populated, industrial and cultural region of Bulgaria that faces considerable earthquake risk. The Sofia seismic zone is located in South-western Bulgaria - the area with pronounce tectonic activity and proved crustal movement. In 19th century the city of Sofia (situated in the centre of the Sofia seismic zone) has experienced two strong earthquakes with epicentral intensity of 10 MSK. During the 20th century the strongest event occurred in the vicinity of the city of Sofia is the 1917 earthquake with MS=5.3 (I0=7-8 MSK64).The 2012 quake occurs in an area characterized by a long quiescence (of 95 years) for moderate events. Moreover, a reduced number of small earthquakes have also been registered in the recent past. The Mw5.6 earthquake is largely felt on the territory of Bulgaria and neighbouring countries. No casualties and severe injuries have been reported. Mostly moderate damages were observed in the cities of Pernik and Sofia and their surroundings. These observations could be assumed indicative for a

  3. Thoracic Injuries in earthquake-related versus non-earthquake-related trauma patients: differentiation via Multi-detector Computed Tomography

    PubMed Central

    Dong, Zhi-hui; Yang, Zhi-gang; Chen, Tian-wu; Chu, Zhi-gang; Deng, Wen; Shao, Heng

    2011-01-01

    PURPOSE: Massive earthquakes are harmful to humankind. This study of a historical cohort aimed to investigate the difference between earthquake-related crush thoracic traumas and thoracic traumas unrelated to earthquakes using a multi-detector Computed Tomography (CT). METHODS: We retrospectively compared an earthquake-exposed cohort of 215 thoracic trauma crush victims of the Sichuan earthquake to a cohort of 215 non-earthquake-related thoracic trauma patients, focusing on the lesions and coexisting injuries to the thoracic cage and the pulmonary parenchyma and pleura using a multi-detector CT. RESULTS: The incidence of rib fracture was elevated in the earthquake-exposed cohort (143 vs. 66 patients in the non-earthquake-exposed cohort, Risk Ratio (RR) = 2.2; p<0.001). Among these patients, those with more than 3 fractured ribs (106/143 vs. 41/66 patients, RR = 1.2; p<0.05) or flail chest (45/143 vs. 11/66 patients, RR = 1.9; p<0.05) were more frequently seen in the earthquake cohort. Earthquake-related crush injuries more frequently resulted in bilateral rib fractures (66/143 vs. 18/66 patients, RR = 1.7; p<0.01). Additionally, the incidence of non-rib fracture was higher in the earthquake cohort (85 vs. 60 patients, RR = 1.4; p<0.01). Pulmonary parenchymal and pleural injuries were more frequently seen in earthquake-related crush injuries (117 vs. 80 patients, RR = 1.5 for parenchymal and 146 vs. 74 patients, RR = 2.0 for pleural injuries; p<0.001). Non-rib fractures, pulmonary parenchymal and pleural injuries had significant positive correlation with rib fractures in these two cohorts. CONCLUSIONS: Thoracic crush traumas resulting from the earthquake were life threatening with a high incidence of bony thoracic fractures. The ribs were frequently involved in bilateral and severe types of fractures, which were accompanied by non-rib fractures, pulmonary parenchymal and pleural injuries. PMID:21789386

  4. Issues on the Japanese Earthquake Hazard Evaluation

    NASA Astrophysics Data System (ADS)

    Hashimoto, M.; Fukushima, Y.; Sagiya, T.

    2013-12-01

    The 2011 Great East Japan Earthquake forced the policy of counter-measurements to earthquake disasters, including earthquake hazard evaluations, to be changed in Japan. Before the March 11, Japanese earthquake hazard evaluation was based on the history of earthquakes that repeatedly occurs and the characteristic earthquake model. The source region of an earthquake was identified and its occurrence history was revealed. Then the conditional probability was estimated using the renewal model. However, the Japanese authorities changed the policy after the megathrust earthquake in 2011 such that the largest earthquake in a specific seismic zone should be assumed on the basis of available scientific knowledge. According to this policy, three important reports were issued during these two years. First, the Central Disaster Management Council issued a new estimate of damages by a hypothetical Mw9 earthquake along the Nankai trough during 2011 and 2012. The model predicts a 34 m high tsunami on the southern Shikoku coast and intensity 6 or higher on the JMA scale in most area of Southwest Japan as the maximum. Next, the Earthquake Research Council revised the long-term earthquake hazard evaluation of earthquakes along the Nankai trough in May 2013, which discarded the characteristic earthquake model and put much emphasis on the diversity of earthquakes. The so-called 'Tokai' earthquake was negated in this evaluation. Finally, another report by the CDMC concluded that, with the current knowledge, it is hard to predict the occurrence of large earthquakes along the Nankai trough using the present techniques, based on the diversity of earthquake phenomena. These reports created sensations throughout the country and local governments are struggling to prepare counter-measurements. These reports commented on large uncertainty in their evaluation near their ends, but are these messages transmitted properly to the public? Earthquake scientists, including authors, are involved in

  5. The physics of an earthquake

    NASA Astrophysics Data System (ADS)

    McCloskey, John

    2008-03-01

    The Sumatra-Andaman earthquake of 26 December 2004 (Boxing Day 2004) and its tsunami will endure in our memories as one of the worst natural disasters of our time. For geophysicists, the scale of the devastation and the likelihood of another equally destructive earthquake set out a series of challenges of how we might use science not only to understand the earthquake and its aftermath but also to help in planning for future earthquakes in the region. In this article a brief account of these efforts is presented. Earthquake prediction is probably impossible, but earth scientists are now able to identify particularly dangerous places for future events by developing an understanding of the physics of stress interaction. Having identified such a dangerous area, a series of numerical Monte Carlo simulations is described which allow us to get an idea of what the most likely consequences of a future earthquake are by modelling the tsunami generated by lots of possible, individually unpredictable, future events. As this article was being written, another earthquake occurred in the region, which had many expected characteristics but was enigmatic in other ways. This has spawned a series of further theories which will contribute to our understanding of this extremely complex problem.

  6. Organizational changes at Earthquakes & Volcanoes

    USGS Publications Warehouse

    Gordon, David W.

    1992-01-01

    Primary responsibility for the preparation of Earthquakes & Volcanoes within the Geological Survey has shifted from the Office of Scientific Publications to the Office of Earthquakes, Volcanoes, and Engineering (OEVE). As a consequence of this reorganization, Henry Spall has stepepd down as Science Editor for Earthquakes & Volcanoes(E&V).

  7. Sense of Community and Depressive Symptoms among Older Earthquake Survivors Following the 2008 Earthquake in Chengdu China

    ERIC Educational Resources Information Center

    Li, Yawen; Sun, Fei; He, Xusong; Chan, Kin Sun

    2011-01-01

    This study examined the impact of an earthquake as well as the role of sense of community as a protective factor against depressive symptoms among older Chinese adults who survived an 8.0 magnitude earthquake in 2008. A household survey of a random sample was conducted 3 months after the earthquake and 298 older earthquake survivors participated…

  8. The Electronic Encyclopedia of Earthquakes

    NASA Astrophysics Data System (ADS)

    Benthien, M.; Marquis, J.; Jordan, T.

    2003-12-01

    The Electronic Encyclopedia of Earthquakes is a collaborative project of the Southern California Earthquake Center (SCEC), the Consortia of Universities for Research in Earthquake Engineering (CUREE) and the Incorporated Research Institutions for Seismology (IRIS). This digital library organizes earthquake information online as a partner with the NSF-funded National Science, Technology, Engineering and Mathematics (STEM) Digital Library (NSDL) and the Digital Library for Earth System Education (DLESE). When complete, information and resources for over 500 Earth science and engineering topics will be included, with connections to curricular materials useful for teaching Earth Science, engineering, physics and mathematics. Although conceived primarily as an educational resource, the Encyclopedia is also a valuable portal to anyone seeking up-to-date earthquake information and authoritative technical sources. "E3" is a unique collaboration among earthquake scientists and engineers to articulate and document a common knowledge base with a shared terminology and conceptual framework. It is a platform for cross-training scientists and engineers in these complementary fields and will provide a basis for sustained communication and resource-building between major education and outreach activities. For example, the E3 collaborating organizations have leadership roles in the two largest earthquake engineering and earth science projects ever sponsored by NSF: the George E. Brown Network for Earthquake Engineering Simulation (CUREE) and the EarthScope Project (IRIS and SCEC). The E3 vocabulary and definitions are also being connected to a formal ontology under development by the SCEC/ITR project for knowledge management within the SCEC Collaboratory. The E3 development system is now fully operational, 165 entries are in the pipeline, and the development teams are capable of producing 20 new, fully reviewed encyclopedia entries each month. Over the next two years teams will

  9. Energy Partition and Variability of Earthquakes

    NASA Astrophysics Data System (ADS)

    Kanamori, H.

    2003-12-01

    During an earthquake the potential energy (strain energy + gravitational energy + rotational energy) is released, and the released potential energy (Δ W) is partitioned into radiated energy (ER), fracture energy (EG), and thermal energy (E H). How Δ W is partitioned into these energies controls the behavior of an earthquake. The merit of the slip-weakening concept is that only ER and EG control the dynamics, and EH can be treated separately to discuss the thermal characteristics of an earthquake. In general, if EG/E_R is small, the event is ``brittle", if EG /ER is large, the event is ``quasi static" or, in more common terms, ``slow earthquakes" or ``creep". If EH is very large, the event may well be called a thermal runaway rather than an earthquake. The difference in energy partition has important implications for the rupture initiation, evolution and excitation of long-period ground motions from very large earthquakes. We review the current state of knowledge on this problem in light of seismological observations and the basic physics of fracture. With seismological methods, we can measure only ER and the lower-bound of Δ W, Δ W0, and estimation of other energies involves many assumptions. ER: Although ER can be directly measured from the radiated waves, its determination is difficult because a large fraction of energy radiated at the source is attenuated during propagation. With the commonly used teleseismic and regional methods, only for events with MW>7 and MW>4, respectively, we can directly measure more than 10% of the total radiated energy. The rest must be estimated after correction for attenuation. Thus, large uncertainties are involved, especially for small earthquakes. Δ W0: To estimate Δ W0, estimation of the source dimension is required. Again, only for large earthquakes, the source dimension can be estimated reliably. With the source dimension, the static stress drop, Δ σ S, and Δ W0, can be estimated. EG: Seismologically, EG is the energy

  10. Deviant Earthquakes: Data-driven Constraints on the Variability in Earthquake Source Properties and Seismic Hazard

    NASA Astrophysics Data System (ADS)

    Trugman, Daniel Taylor

    The complexity of the earthquake rupture process makes earthquakes inherently unpredictable. Seismic hazard forecasts often presume that the rate of earthquake occurrence can be adequately modeled as a space-time homogenenous or stationary Poisson process and that the relation between the dynamical source properties of small and large earthquakes obey self-similar scaling relations. While these simplified models provide useful approximations and encapsulate the first-order statistical features of the historical seismic record, they are inconsistent with the complexity underlying earthquake occurrence and can lead to misleading assessments of seismic hazard when applied in practice. The six principle chapters of this thesis explore the extent to which the behavior of real earthquakes deviates from these simplified models, and the implications that the observed deviations have for our understanding of earthquake rupture processes and seismic hazard. Chapter 1 provides a brief thematic overview and introduction to the scope of this thesis. Chapter 2 examines the complexity of the 2010 M7.2 El Mayor-Cucapah earthquake, focusing on the relation between its unexpected and unprecedented occurrence and anthropogenic stresses from the nearby Cerro Prieto Geothermal Field. Chapter 3 compares long-term changes in seismicity within California's three largest geothermal fields in an effort to characterize the relative influence of natural and anthropogenic stress transients on local seismic hazard. Chapter 4 describes a hybrid, hierarchical clustering algorithm that can be used to relocate earthquakes using waveform cross-correlation, and applies the new algorithm to study the spatiotemporal evolution of two recent seismic swarms in western Nevada. Chapter 5 describes a new spectral decomposition technique that can be used to analyze the dynamic source properties of large datasets of earthquakes, and applies this approach to revisit the question of self-similar scaling of

  11. Predecessors of the giant 1960 Chile earthquake

    USGS Publications Warehouse

    Cisternas, M.; Atwater, B.F.; Torrejon, F.; Sawai, Y.; Machuca, G.; Lagos, M.; Eipert, A.; Youlton, C.; Salgado, I.; Kamataki, T.; Shishikura, M.; Rajendran, C.P.; Malik, J.K.; Rizal, Y.; Husni, M.

    2005-01-01

    It is commonly thought that the longer the time since last earthquake, the larger the next earthquake's slip will be. But this logical predictor of earthquake size, unsuccessful for large earthquakes on a strike-slip fault, fails also with the giant 1960 Chile earthquake of magnitude 9.5 (ref. 3). Although the time since the preceding earthquake spanned 123 years (refs 4, 5), the estimated slip in 1960, which occurred on a fault between the Nazca and South American tectonic plates, equalled 250-350 years' worth of the plate motion. Thus the average interval between such giant earthquakes on this fault should span several centuries. Here we present evidence that such long intervals were indeed typical of the last two millennia. We use buried soils and sand layers as records of tectonic subsidence and tsunami inundation at an estuary midway along the 1960 rupture. In these records, the 1960 earthquake ended a recurrence interval that had begun almost four centuries before, with an earthquake documented by Spanish conquistadors in 1575. Two later earthquakes, in 1737 and 1837, produced little if any subsidence or tsunami at the estuary and they therefore probably left the fault partly loaded with accumulated plate motion that the 1960 earthquake then expended. ?? 2005 Nature Publishing Group.

  12. Predecessors of the giant 1960 Chile earthquake.

    PubMed

    Cisternas, Marco; Atwater, Brian F; Torrejón, Fernando; Sawai, Yuki; Machuca, Gonzalo; Lagos, Marcelo; Eipert, Annaliese; Youlton, Cristián; Salgado, Ignacio; Kamataki, Takanobu; Shishikura, Masanobu; Rajendran, C P; Malik, Javed K; Rizal, Yan; Husni, Muhammad

    2005-09-15

    It is commonly thought that the longer the time since last earthquake, the larger the next earthquake's slip will be. But this logical predictor of earthquake size, unsuccessful for large earthquakes on a strike-slip fault, fails also with the giant 1960 Chile earthquake of magnitude 9.5 (ref. 3). Although the time since the preceding earthquake spanned 123 years (refs 4, 5), the estimated slip in 1960, which occurred on a fault between the Nazca and South American tectonic plates, equalled 250-350 years' worth of the plate motion. Thus the average interval between such giant earthquakes on this fault should span several centuries. Here we present evidence that such long intervals were indeed typical of the last two millennia. We use buried soils and sand layers as records of tectonic subsidence and tsunami inundation at an estuary midway along the 1960 rupture. In these records, the 1960 earthquake ended a recurrence interval that had begun almost four centuries before, with an earthquake documented by Spanish conquistadors in 1575. Two later earthquakes, in 1737 and 1837, produced little if any subsidence or tsunami at the estuary and they therefore probably left the fault partly loaded with accumulated plate motion that the 1960 earthquake then expended.

  13. Next-Day Earthquake Forecasts for California

    NASA Astrophysics Data System (ADS)

    Werner, M. J.; Jackson, D. D.; Kagan, Y. Y.

    2008-12-01

    We implemented a daily forecast of m > 4 earthquakes for California in the format suitable for testing in community-based earthquake predictability experiments: Regional Earthquake Likelihood Models (RELM) and the Collaboratory for the Study of Earthquake Predictability (CSEP). The forecast is based on near-real time earthquake reports from the ANSS catalog above magnitude 2 and will be available online. The model used to generate the forecasts is based on the Epidemic-Type Earthquake Sequence (ETES) model, a stochastic model of clustered and triggered seismicity. Our particular implementation is based on the earlier work of Helmstetter et al. (2006, 2007), but we extended the forecast to all of Cali-fornia, use more data to calibrate the model and its parameters, and made some modifications. Our forecasts will compete against the Short-Term Earthquake Probabilities (STEP) forecasts of Gersten-berger et al. (2005) and other models in the next-day testing class of the CSEP experiment in California. We illustrate our forecasts with examples and discuss preliminary results.

  14. The mechanism of earthquake

    NASA Astrophysics Data System (ADS)

    Lu, Kunquan; Cao, Zexian; Hou, Meiying; Jiang, Zehui; Shen, Rong; Wang, Qiang; Sun, Gang; Liu, Jixing

    2018-03-01

    The physical mechanism of earthquake remains a challenging issue to be clarified. Seismologists used to attribute shallow earthquake to the elastic rebound of crustal rocks. The seismic energy calculated following the elastic rebound theory and with the data of experimental results upon rocks, however, shows a large discrepancy with measurement — a fact that has been dubbed as “the heat flow paradox”. For the intermediate-focus and deep-focus earthquakes, both occurring in the region of the mantle, there is not reasonable explanation either. This paper will discuss the physical mechanism of earthquake from a new perspective, starting from the fact that both the crust and the mantle are discrete collective system of matters with slow dynamics, as well as from the basic principles of physics, especially some new concepts of condensed matter physics emerged in the recent years. (1) Stress distribution in earth’s crust: Without taking the tectonic force into account, according to the rheological principle of “everything flows”, the normal stress and transverse stress must be balanced due to the effect of gravitational pressure over a long period of time, thus no differential stress in the original crustal rocks is to be expected. The tectonic force is successively transferred and accumulated via stick-slip motions of rock blocks to squeeze the fault gouge and then exerted upon other rock blocks. The superposition of such additional lateral tectonic force and the original stress gives rise to the real-time stress in crustal rocks. The mechanical characteristics of fault gouge are different from rocks as it consists of granular matters. The elastic moduli of the fault gouges are much less than those of rocks, and they become larger with increasing pressure. This peculiarity of the fault gouge leads to a tectonic force increasing with depth in a nonlinear fashion. The distribution and variation of the tectonic stress in the crust are specified. (2) The

  15. A comparison study of 2006 Java earthquake and other Tsunami earthquakes

    NASA Astrophysics Data System (ADS)

    Ji, C.; Shao, G.

    2006-12-01

    We revise the slip processes of July 17 2006 Java earthquakes by combined inverting teleseismic body wave, long period surface waves, as well as the broadband records at Christmas island (XMIS), which is 220 km away from the hypocenter and so far the closest observation for a Tsunami earthquake. Comparing with the previous studies, our approach considers the amplitude variations of surface waves with source depths as well as the contribution of ScS phase, which usually has amplitudes compatible with that of direct S phase for such low angle thrust earthquakes. The fault dip angles are also refined using the Love waves observed along fault strike direction. Our results indicate that the 2006 event initiated at a depth around 12 km and unilaterally rupture southeast for 150 sec with a speed of 1.0 km/sec. The revised fault dip is only about 6 degrees, smaller than the Harvard CMT (10.5 degrees) but consistent with that of 1994 Java earthquake. The smaller fault dip results in a larger moment magnitude (Mw=7.9) for a PREM earth, though it is dependent on the velocity structure used. After verified with 3D SEM forward simulation, we compare the inverted result with the revised slip models of 1994 Java and 1992 Nicaragua earthquakes derived using the same wavelet based finite fault inversion methodology.

  16. Turkish Children's Ideas about Earthquakes

    ERIC Educational Resources Information Center

    Simsek, Canan Lacin

    2007-01-01

    Earthquake, a natural disaster, is among the fundamental problems of many countries. If people know how to protect themselves from earthquake and arrange their life styles in compliance with this, damage they will suffer will reduce to that extent. In particular, a good training regarding earthquake to be received in primary schools is considered…

  17. Differential energy radiation from two earthquakes in Japan with identical Mw: The Kyushu 1996 and Tottori 2000 earthquakes

    USGS Publications Warehouse

    Choy, G.L.; Boatwright, J.

    2009-01-01

    We examine two closely located earthquakes in Japan that had identical moment magnitudes Mw but significantly different energy magnitudes Me. We use teleseismic data from the Global Seismograph Network and strong-motion data from the National Research Institute for Earth Science and Disaster Prevention's K-Net to analyze the 19 October 1996 Kyushu earthquake (Mw 6.7, Me 6.6) and the 6 October 2000 Tottori earthquake (Mw 6.7, Me 7.4). To obtain regional estimates of radiated energy ES we apply a spectral technique to regional (<200 km) waveforms that are dominated by S and Lg waves. For the thrust-fault Kyushu earthquake, we estimate an average regional attenuation Q(f) 230f0:65. For the strike-slip Tottori earthquake, the average regional attenuation is Q(f) 180f0:6. These attenuation functions are similar to those derived from studies of both California and Japan earthquakes. The regional estimate of ES for the Kyushu earthquake, 3:8 ?? 1014 J, is significantly smaller than that for the Tottori earthquake, ES 1:3 ?? 1015 J. These estimates correspond well with the teleseismic estimates of 3:9 ?? 1014 J and 1:8 ?? 1015 J, respectively. The apparent stress (Ta = ??Es/M0 with ?? equal to rigidity) for the Kyushu earthquake is 4 times smaller than the apparent stress for the Tottori earthquake. In terms of the fault maturity model, the significantly greater release of energy by the strike-slip Tottori earthquake can be related to strong deformation in an immature intraplate setting. The relatively lower energy release of the thrust-fault Kyushu earthquake can be related to rupture on mature faults at a subduction environment. The consistence between teleseismic and regional estimates of ES is particularly significant as teleseismic data for computing ES are routinely available for all large earthquakes whereas often there are no near-field data.

  18. Global earthquake fatalities and population

    USGS Publications Warehouse

    Holzer, Thomas L.; Savage, James C.

    2013-01-01

    Modern global earthquake fatalities can be separated into two components: (1) fatalities from an approximately constant annual background rate that is independent of world population growth and (2) fatalities caused by earthquakes with large human death tolls, the frequency of which is dependent on world population. Earthquakes with death tolls greater than 100,000 (and 50,000) have increased with world population and obey a nonstationary Poisson distribution with rate proportional to population. We predict that the number of earthquakes with death tolls greater than 100,000 (50,000) will increase in the 21st century to 8.7±3.3 (20.5±4.3) from 4 (7) observed in the 20th century if world population reaches 10.1 billion in 2100. Combining fatalities caused by the background rate with fatalities caused by catastrophic earthquakes (>100,000 fatalities) indicates global fatalities in the 21st century will be 2.57±0.64 million if the average post-1900 death toll for catastrophic earthquakes (193,000) is assumed.

  19. Large earthquakes and creeping faults

    USGS Publications Warehouse

    Harris, Ruth A.

    2017-01-01

    Faults are ubiquitous throughout the Earth's crust. The majority are silent for decades to centuries, until they suddenly rupture and produce earthquakes. With a focus on shallow continental active-tectonic regions, this paper reviews a subset of faults that have a different behavior. These unusual faults slowly creep for long periods of time and produce many small earthquakes. The presence of fault creep and the related microseismicity helps illuminate faults that might not otherwise be located in fine detail, but there is also the question of how creeping faults contribute to seismic hazard. It appears that well-recorded creeping fault earthquakes of up to magnitude 6.6 that have occurred in shallow continental regions produce similar fault-surface rupture areas and similar peak ground shaking as their locked fault counterparts of the same earthquake magnitude. The behavior of much larger earthquakes on shallow creeping continental faults is less well known, because there is a dearth of comprehensive observations. Computational simulations provide an opportunity to fill the gaps in our understanding, particularly of the dynamic processes that occur during large earthquake rupture and arrest.

  20. How fault geometry controls earthquake magnitude

    NASA Astrophysics Data System (ADS)

    Bletery, Q.; Thomas, A.; Karlstrom, L.; Rempel, A. W.; Sladen, A.; De Barros, L.

    2016-12-01

    Recent large megathrust earthquakes, such as the Mw9.3 Sumatra-Andaman earthquake in 2004 and the Mw9.0 Tohoku-Oki earthquake in 2011, astonished the scientific community. The first event occurred in a relatively low-convergence-rate subduction zone where events of its size were unexpected. The second event involved 60 m of shallow slip in a region thought to be aseismicaly creeping and hence incapable of hosting very large magnitude earthquakes. These earthquakes highlight gaps in our understanding of mega-earthquake rupture processes and the factors controlling their global distribution. Here we show that gradients in dip angle exert a primary control on mega-earthquake occurrence. We calculate the curvature along the major subduction zones of the world and show that past mega-earthquakes occurred on flat (low-curvature) interfaces. A simplified analytic model demonstrates that shear strength heterogeneity increases with curvature. Stress loading on flat megathrusts is more homogeneous and hence more likely to be released simultaneously over large areas than on highly-curved faults. Therefore, the absence of asperities on large faults might counter-intuitively be a source of higher hazard.

  1. Observing Triggered Earthquakes Across Iran with Calibrated Earthquake Locations

    NASA Astrophysics Data System (ADS)

    Karasozen, E.; Bergman, E.; Ghods, A.; Nissen, E.

    2016-12-01

    We investigate earthquake triggering phenomena in Iran by analyzing patterns of aftershock activity around mapped surface ruptures. Iran has an intense level of seismicity (> 40,000 events listed in the ISC Bulletin since 1960) due to it accommodating a significant portion of the continental collision between Arabia and Eurasia. There are nearly thirty mapped surface ruptures associated with earthquakes of M 6-7.5, mostly in eastern and northwestern Iran, offering a rich potential to study the kinematics of earthquake nucleation, rupture propagation, and subsequent triggering. However, catalog earthquake locations are subject to up to 50 km of location bias from the combination of unknown Earth structure and unbalanced station coverage, making it challenging to assess both the rupture directivity of larger events and the spatial patterns of their aftershocks. To overcome this limitation, we developed a new two-tiered multiple-event relocation approach to obtain hypocentral parameters that are minimally biased and have realistic uncertainties. In the first stage, locations of small clusters of well-recorded earthquakes at local spatial scales (100s of events across 100 km length scales) are calibrated either by using near-source arrival times or independent location constraints (e.g. local aftershock studies, InSAR solutions), using an implementation of the Hypocentroidal Decomposition relocation technique called MLOC. Epicentral uncertainties are typically less than 5 km. Then, these events are used as prior constraints in the code BayesLoc, a Bayesian relocation technique that can handle larger datasets, to yield region-wide calibrated hypocenters (1000s of events over 1000 km length scales). With locations and errors both calibrated, the pattern of aftershock activity can reveal the type of the earthquake triggering: dynamic stress changes promote an increase in the seismicity rate in the direction of unilateral propagation, whereas static stress changes should

  2. Earthquake casualty models within the USGS Prompt Assessment of Global Earthquakes for Response (PAGER) system

    USGS Publications Warehouse

    Jaiswal, Kishor; Wald, David J.; Earle, Paul S.; Porter, Keith A.; Hearne, Mike

    2011-01-01

    Since the launch of the USGS’s Prompt Assessment of Global Earthquakes for Response (PAGER) system in fall of 2007, the time needed for the U.S. Geological Survey (USGS) to determine and comprehend the scope of any major earthquake disaster anywhere in the world has been dramatically reduced to less than 30 min. PAGER alerts consist of estimated shaking hazard from the ShakeMap system, estimates of population exposure at various shaking intensities, and a list of the most severely shaken cities in the epicentral area. These estimates help government, scientific, and relief agencies to guide their responses in the immediate aftermath of a significant earthquake. To account for wide variability and uncertainty associated with inventory, structural vulnerability and casualty data, PAGER employs three different global earthquake fatality/loss computation models. This article describes the development of the models and demonstrates the loss estimation capability for earthquakes that have occurred since 2007. The empirical model relies on country-specific earthquake loss data from past earthquakes and makes use of calibrated casualty rates for future prediction. The semi-empirical and analytical models are engineering-based and rely on complex datasets including building inventories, time-dependent population distributions within different occupancies, the vulnerability of regional building stocks, and casualty rates given structural collapse.

  3. In the shadow of 1857-the effect of the great Ft. Tejon earthquake on subsequent earthquakes in southern California

    USGS Publications Warehouse

    Harris, R.A.; Simpson, R.W.

    1996-01-01

    The great 1857 Fort Tejon earthquake is the largest earthquake to have hit southern California during the historic period. We investigated if seismicity patterns following 1857 could be due to static stress changes generated by the 1857 earthquake. When post-1857 earthquakes with unknown focal mechanisms were assigned strike-slip mechanisms with strike and rake determined by the nearest active fault, 13 of the 13 southern California M???5.5 earthquakes between 1857 and 1907 were encouraged by the 1857 rupture. When post-1857 earthquakes in the Transverse Ranges with unknown focal mechanisms were assigned reverse mechanisms and all other events were assumed strike-slip, 11 of the 13 earthquakes were encouraged by the 1857 earthquake. These results show significant correlations between static stress changes and seismicity patterns. The correlation disappears around 1907, suggesting that tectonic loading began to overwhelm the effect of the 1857 earthquake early in the 20th century.

  4. Intraplate triggered earthquakes: Observations and interpretation

    USGS Publications Warehouse

    Hough, S.E.; Seeber, L.; Armbruster, J.G.

    2003-01-01

    We present evidence that at least two of the three 1811-1812 New Madrid, central United States, mainshocks and the 1886 Charleston, South Carolina, earthquake triggered earthquakes at regional distances. In addition to previously published evidence for triggered earthquakes in the northern Kentucky/southern Ohio region in 1812, we present evidence suggesting that triggered events might have occurred in the Wabash Valley, to the south of the New Madrid Seismic Zone, and near Charleston, South Carolina. We also discuss evidence that earthquakes might have been triggered in northern Kentucky within seconds of the passage of surface waves from the 23 January 1812 New Madrid mainshock. After the 1886 Charleston earthquake, accounts suggest that triggered events occurred near Moodus, Connecticut, and in southern Indiana. Notwithstanding the uncertainty associated with analysis of historical accounts, there is evidence that at least three out of the four known Mw 7 earthquakes in the central and eastern United States seem to have triggered earthquakes at distances beyond the typically assumed aftershock zone of 1-2 mainshock fault lengths. We explore the possibility that remotely triggered earthquakes might be common in low-strain-rate regions. We suggest that in a low-strain-rate environment, permanent, nonelastic deformation might play a more important role in stress accumulation than it does in interplate crust. Using a simple model incorporating elastic and anelastic strain release, we show that, for realistic parameter values, faults in intraplate crust remain close to their failure stress for a longer part of the earthquake cycle than do faults in high-strain-rate regions. Our results further suggest that remotely triggered earthquakes occur preferentially in regions of recent and/or future seismic activity, which suggests that faults are at a critical stress state in only some areas. Remotely triggered earthquakes may thus serve as beacons that identify regions of

  5. Earthquakes, July-August 1991

    USGS Publications Warehouse

    Person, W.J.

    1992-01-01

    There was one major earthquake during this reporting period-a magnitude 7.1 shock off the coast of Northern California on August 17. Earthquake-related deaths were reported from Indonesia, Romania, Peru, and Iraq. 

  6. Earthquakes-Rattling the Earth's Plumbing System

    USGS Publications Warehouse

    Sneed, Michelle; Galloway, Devin L.; Cunningham, William L.

    2003-01-01

    Hydrogeologic responses to earthquakes have been known for decades, and have occurred both close to, and thousands of miles from earthquake epicenters. Water wells have become turbid, dry or begun flowing, discharge of springs and ground water to streams has increased and new springs have formed, and well and surface-water quality have become degraded as a result of earthquakes. Earthquakes affect our Earth’s intricate plumbing system—whether you live near the notoriously active San Andreas Fault in California, or far from active faults in Florida, an earthquake near or far can affect you and the water resources you depend on.

  7. Measuring the size of an earthquake

    USGS Publications Warehouse

    Spence, W.

    1977-01-01

    Earthquakes occur in a broad range of sizes. A rock burst in an Idaho silver mine may involve the fracture of 1 meter of rock; the 1965 Rat island earthquake in the Aleutian arc involved a 650-kilometer lenght of Earth's crust. Earthquakes can be even smaller and even larger. if an earthquake is felt or causes perceptible surface damage, then its intesnity of shaking can be subjectively estimated. But many large earthquakes occur in oceanic area or at great focal depths. These are either simply not felt or their felt pattern does not really indicate their true size. 

  8. Volunteers in the earthquake hazard reduction program

    USGS Publications Warehouse

    Ward, P.L.

    1978-01-01

    With this in mind, I organized a small workshop for approximately 30 people on February 2 and 3, 1978, in Menlo Park, Calif. the purpose of the meeting was to discuss methods of involving volunteers in a meaningful way in earthquake research and in educating the public about earthquake hazards. The emphasis was on earthquake prediction research, but the discussions covered the whole earthquake hazard reduction program. Representatives attended from the earthquake research community, from groups doing socioeconomic research on earthquake matters, and from a wide variety of organizations who might sponsor volunteers. 

  9. Real-time earthquake source imaging: An offline test for the 2011 Tohoku earthquake

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Wang, Rongjiang; Zschau, Jochen; Parolai, Stefano; Dahm, Torsten

    2014-05-01

    In recent decades, great efforts have been expended in real-time seismology aiming at earthquake and tsunami early warning. One of the most important issues is the real-time assessment of earthquake rupture processes using near-field seismogeodetic networks. Currently, earthquake early warning systems are mostly based on the rapid estimate of P-wave magnitude, which contains generally large uncertainties and the known saturation problem. In the case of the 2011 Mw9.0 Tohoku earthquake, JMA (Japan Meteorological Agency) released the first warning of the event with M7.2 after 25 s. The following updates of the magnitude even decreased to M6.3-6.6. Finally, the magnitude estimate stabilized at M8.1 after about two minutes. This led consequently to the underestimated tsunami heights. By using the newly developed Iterative Deconvolution and Stacking (IDS) method for automatic source imaging, we demonstrate an offline test for the real-time analysis of the strong-motion and GPS seismograms of the 2011 Tohoku earthquake. The results show that we had been theoretically able to image the complex rupture process of the 2011 Tohoku earthquake automatically soon after or even during the rupture process. In general, what had happened on the fault could be robustly imaged with a time delay of about 30 s by using either the strong-motion (KiK-net) or the GPS (GEONET) real-time data. This implies that the new real-time source imaging technique is helpful to reduce false and missing warnings, and therefore should play an important role in future tsunami early warning and earthquake rapid response systems.

  10. Protecting Your Family From Earthquakes-The Seven Steps to Earthquake Safety (in Spanish and English)

    USGS Publications Warehouse

    Developed by American Red Cross, Asian Pacific Fund

    2007-01-01

    This book is provided here to share an important message on emergency preparedness. Historically, we have suffered earthquakes here in the San Francisco Bay Area that have caused severe hardship for residents and incredible damage to our cities. It is likely we will experience a severe earthquake within the next 30 years. Many of us come from other countries where we have experienced earth- quakes, so we believe that we understand them. However, the way we prepare for earthquakes in our home country may be different from the way it is necessary to prepare for earthquakes here. Very f w people die from collapsing buildings in the Bay Area because most structures are built to stand up to the shaking. But it is quite possible that your family will be without medical care or grocery stores and separated from one another for several days to weeks. It will ultimately be up to you to keep your family safe until help arrives, so we are asking you to join us in learning to take care of your family before, during, and after an earthquake. The first step is to read this book. Everyone in your family, children and adults, can learn how to prepare for an earthquake. Then take advantage of the American Red Cross Earthquake Preparedness training courses offered in your community. These preparedness courses are free, and also offered in Spanish and available to everyone in the community regardless of family history, leg al status, gender, or age. We encourage you to take one of these free training workshops. Look on the back cover for more information. Remember that an earthquake can occur without warning, and the only way that we can reduce the harm caused by earthquakes is to be prepared. Get Prepared!

  11. Effect of tree thinning and litter removal on the radiocesium (Cs-134, 137) discharge rates in the Kawauchi forest plantation (Fukushima Prefecture, northern Japan)

    NASA Astrophysics Data System (ADS)

    López-Vicente, Manuel; Onda, Yuichi; Takahashi, Junko; Kato, Hiroaki; Hisadome, Keigo

    2016-04-01

    On 11 March 2011 a 9.0 earthquake and the resulting tsunami occurred in central-eastern Japan triggering, one day after, the Fukushima Dai-ichi nuclear power plant (DNPP) accident. Despite the bulk of radionuclides (ca. 80%) were transported offshore and out over the Pacific Ocean, significant wet and dry deposits of those radionuclides occurred mainly in the Fukushima Prefecture and in a minor way in the Miyagi, Tochigi, Gunma and Ibaraki Prefectures. As a consequence and among other radionuclides, a total of 511,000 TBq of I-131, 13,500 TBq of Cs-134 and 13,600 TBq of Cs-137 were released into the atmosphere and the ocean, contaminating cultivated soils, rivers, settlements and forested areas. This accident caused severe environmental and economic damages. Several decontamination practices have done, including tree thinning and litter removal within the forests and tree plantations. In this study we analysed the effect of eight different management practices on the radiocesium (Cs-134 and Cs-137) discharge rates during 20 months (May'2013 - Dec'2014) in a Japanese cedar (Cryptomeria japonica) plantation (stand age of 57 years), located in a hillslope near the Kawauchi village, Fukushima Prefecture, northern Japan. This study area (37⁰ 20' 04" N, 140⁰ 53' 13.5" E) is located 16 km southwestern from the DNPP and within the evacuation area. The soils are Andosols. Ten runoff plots (5 x 2 meters) were installed and measurements started on May 2013. Two plots remained without any treatment as control plots and the other eight plots represented the following management practices: Mng1) Litter removal + clear-cutting (no sheet); Mng2) Litter removal + clear-cutting (no sheet); Mng3) Litter removal + clear-cutting (no sheet); Mng4) Litter removal; Mng5) Thinning (logged area); Mng6) Thinning (under remnant trees); Mng7) Litter removal + thinning (logged area); Mng8) Litter removal + thinning (under remnant trees). Each plot had a gauging station and sediment samples

  12. Links Between Earthquake Characteristics and Subducting Plate Heterogeneity in the 2016 Pedernales Ecuador Earthquake Rupture Zone

    NASA Astrophysics Data System (ADS)

    Bai, L.; Mori, J. J.

    2016-12-01

    The collision between the Indian and Eurasian plates formed the Himalayas, the largest orogenic belt on the Earth. The entire region accommodates shallow earthquakes, while intermediate-depth earthquakes are concentrated at the eastern and western Himalayan syntaxis. Here we investigate the focal depths, fault plane solutions, and source rupture process for three earthquake sequences, which are located at the western, central and eastern regions of the Himalayan orogenic belt. The Pamir-Hindu Kush region is located at the western Himalayan syntaxis and is characterized by extreme shortening of the upper crust and strong interaction of various layers of the lithosphere. Many shallow earthquakes occur on the Main Pamir Thrust at focal depths shallower than 20 km, while intermediate-deep earthquakes are mostly located below 75 km. Large intermediate-depth earthquakes occur frequently at the western Himalayan syntaxis about every 10 years on average. The 2015 Nepal earthquake is located in the central Himalayas. It is a typical megathrust earthquake that occurred on the shallow portion of the Main Himalayan Thrust (MHT). Many of the aftershocks are located above the MHT and illuminate faulting structures in the hanging wall with dip angles that are steeper than the MHT. These observations provide new constraints on the collision and uplift processes for the Himalaya orogenic belt. The Indo-Burma region is located south of the eastern Himalayan syntaxis, where the strike of the plate boundary suddenly changes from nearly east-west at the Himalayas to nearly north-south at the Burma Arc. The Burma arc subduction zone is a typical oblique plate convergence zone. The eastern boundary is the north-south striking dextral Sagaing fault, which hosts many shallow earthquakes with focal depth less than 25 km. In contrast, intermediate-depth earthquakes along the subduction zone reflect east-west trending reverse faulting.

  13. Prospective Validation of Pre-earthquake Atmospheric Signals and Their Potential for Short–term Earthquake Forecasting

    NASA Astrophysics Data System (ADS)

    Ouzounov, Dimitar; Pulinets, Sergey; Hattori, Katsumi; Lee, Lou; Liu, Tiger; Kafatos, Menas

    2015-04-01

    We are presenting the latest development in multi-sensors observations of short-term pre-earthquake phenomena preceding major earthquakes. Our challenge question is: "Whether such pre-earthquake atmospheric/ionospheric signals are significant and could be useful for early warning of large earthquakes?" To check the predictive potential of atmospheric pre-earthquake signals we have started to validate anomalous ionospheric / atmospheric signals in retrospective and prospective modes. The integrated satellite and terrestrial framework (ISTF) is our method for validation and is based on a joint analysis of several physical and environmental parameters (Satellite thermal infrared radiation (STIR), electron concentration in the ionosphere (GPS/TEC), radon/ion activities, air temperature and seismicity patterns) that were found to be associated with earthquakes. The science rationale for multidisciplinary analysis is based on concept Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) [Pulinets and Ouzounov, 2011], which explains the synergy of different geospace processes and anomalous variations, usually named short-term pre-earthquake anomalies. Our validation processes consist in two steps: (1) A continuous retrospective analysis preformed over two different regions with high seismicity- Taiwan and Japan for 2003-2009 (2) Prospective testing of STIR anomalies with potential for M5.5+ events. The retrospective tests (100+ major earthquakes, M>5.9, Taiwan and Japan) show STIR anomalous behavior before all of these events with false negatives close to zero. False alarm ratio for false positives is less then 25%. The initial prospective testing for STIR shows systematic appearance of anomalies in advance (1-30 days) to the M5.5+ events for Taiwan, Kamchatka-Sakhalin (Russia) and Japan. Our initial prospective results suggest that our approach show a systematic appearance of atmospheric anomalies, one to several days prior to the largest earthquakes That feature could be

  14. Earthquakes, September-October 1984

    USGS Publications Warehouse

    Person, W.J.

    1985-01-01

    In the United States, Wyoming experienced a couple of moderate earthquakes, and off the coast of northern California, a strong earthquake shook much of the northern coast of California and parts of the Oregon coast. 

  15. Earthquakes, November-December 1977

    USGS Publications Warehouse

    Person, W.J.

    1978-01-01

    In the United States, the largest earthquake during this reporting period was a magntidue 6.6 in the Andreanof Islands, which are part of the Aleutian Islands chain, on November 4 that caused some minor damage. Northern California was struck by a magnitude 4.8 earthquake on November 22 causing moderate damage in the Willits area. This was the most damaging quake in the United States during the year. Two major earthquakes of magntidues 7.0 or above to 14 for the year. 

  16. Early Earthquakes of the Americas

    NASA Astrophysics Data System (ADS)

    Ni, James

    2004-11-01

    Robert Kovach's second book looks at the interplay of earthquake and volcanic events, archeology, and history in the Americas. Throughout history, major earthquakes have caused the deaths of millions of people and have damaged countless cities. Earthquakes undoubtedly damaged prehistoric cities in the Americas, and evidence of these events could be preserved in archeological records. Kovach asks, Did indigenous native cultures-Indians of the Pacific Northwest, Aztecs, Mayas, and Incas-document their natural history? Some events have been explicitly documented, for example, in Mayan codices, but many may have been recorded as myth and legend. Kovach's discussions of how early cultures dealt with fearful events such as earthquakes and volcanic eruptions are colorful, informative, and entertaining, and include, for example, a depiction of how the Maya would talk to maize plants in their fields during earthquakes to reassure them.

  17. Modelling Seasonal Brucellosis Epidemics in Bayingolin Mongol Autonomous Prefecture of Xinjiang, China, 2010–2014

    PubMed Central

    Lou, Pengwei; Wang, Lei; Zhang, Xueliang; Xu, Jiabo

    2016-01-01

    Brucellosis is one of the severe public health problems; the cumulative number of new human brucellosis cases reached 211515 from 2010 to 2014 in China. Bayingolin Mongol Autonomous Prefecture is situated in the southeast of Xinjiang, where brucellosis infection occurs every year. Based on the reported data of newly acute human brucellosis cases for each season in Bayingolin Mongol Autonomous Prefecture, we proposed a susceptible, exposed, infected, and vaccinated (SEIV) model with periodic transmission rates to investigate the seasonal brucellosis transmission dynamics among sheep/cattle and from sheep/cattle to humans. Compared with the criteria of MAPE and RMSPE, the model simulations agree to the data on newly acute human brucellosis. We predict that the number of newly acute human brucellosis is increasing and will peak 15325 [95% CI: 11920–18242] around the summer of 2023. We also estimate the basic reproduction number R 0 = 2.5524 [95% CI: 2.5129–2.6225] and perform some sensitivity analysis of the newly acute human brucellosis cases and the basic reproduction number R 0 in terms of model parameters. Our study demonstrates that reducing the birth number of sheep/cattle, raising the slaughter rate of infected sheep/cattle, increasing the vaccination rate of susceptible sheep/cattle, and decreasing the loss rate of vaccination are effective strategies to control brucellosis epidemic. PMID:27872852

  18. Dynamic fault rupture model of the 2008 Iwate-Miyagi Nairiku earthquake, Japan; Role of rupture velocity changes on extreme ground motions

    NASA Astrophysics Data System (ADS)

    Pulido Hernandez, N. E.; Dalguer Gudiel, L. A.; Aoi, S.

    2009-12-01

    The Iwate-Miyagi Nairiku earthquake, a reverse earthquake occurred in the southern Iwate prefecture Japan (2008/6/14), produced the largest peak ground acceleration recorded to date (4g) (Aoi et al. 2008), at the West Ichinoseki (IWTH25), KiK-net strong motion station of NIED. This station which is equipped with surface and borehole accelerometers (GL-260), also recorded very high peak accelerations up to 1g at the borehole level, despite being located in a rock site. From comparison of spectrograms of the observed surface and borehole records at IWTH25, Pulido et. al (2008) identified two high frequency (HF) ground motion events located at 4.5s and 6.3s originating at the source, which likely derived in the extreme observed accelerations of 3.9g and 3.5g at IWTH25. In order to understand the generation mechanism of these HF events we performed a dynamic fault rupture model of the Iwate-Miyagi Nairiku earthquake by using the Support Operator Rupture Dynamics (SORD) code, (Ely et al., 2009). SORD solves the elastodynamic equation using a generalized finite difference method that can utilize meshes of arbitrary structure and is capable of handling geometries appropriate to thrust earthquakes. Our spontaneous dynamic rupture model of the Iwate-Miyagi Nairiku earthquake is governed by the simple slip weakening friction law. The dynamic parameters, stress drop, strength excess and critical slip weakening distance are estimated following the procedure described in Pulido and Dalguer (2009) [PD09]. These parameters develop earthquake rupture consistent with the final slip obtained by kinematic source inversion of near source strong ground motion recordings. The dislocation model of this earthquake is characterized by a patch of large slip located ~7 km south of the hypocenter (Suzuki et al. 2009). Our results for the calculation of stress drop follow a similar pattern. Using the rupture times obtained from the dynamic model of the Iwate-Miyagi Nairiku earthquake we

  19. The earthquake disaster risk characteristic and the problem in the earthquake emergency rescue of mountainous southwestern Sichuan

    NASA Astrophysics Data System (ADS)

    Yuan, S.; Xin, C.; Ying, Z.

    2016-12-01

    In recent years, earthquake disaster occurred frequently in Chinese mainland, the secondary disaster which have been caused by it is more serious in mountainous region. Because of the influence of terrain and geological conditions, the difficulty of earthquake emergency rescue work greatly increased, rescue force is also urged. Yet, it has been studied less on earthquake emergency rescue in mountainous region, the research in existing equipment whether can meet the actual needs of local earthquake emergency rescue is poorly. This paper intends to discuss and solve these problems. Through the mountainous regions Ganzi and Liangshan states in Sichuan field research, we investigated the process of earthquake emergency response and the projects for rescue force after an earthquake, and we also collected and collated local rescue force based data. By consulting experts and statistical analyzing the basic data, there are mainly two problems: The first is about local rescue force, they are poorly equipped and lack in the knowledge of medical help or identify architectural structure. There are no countries to establish a sound financial investment protection mechanism. Also, rescue equipment's updates and maintenance; The second problem is in earthquake emergency rescue progress. In the complicated geologic structure of mountainous regions, traffic and communication may be interrupted by landslides and mud-rock flows after earthquake. The outside rescue force may not arrive in time, rescue equipment was transported by manpower. Because of unknown earthquake disaster information, the local rescue force was deployed unreasonable. From the above, the local government worker should analyze the characteristics of the earthquake disaster in mountainous regions, and research how to improve their earthquake emergency rescue ability. We think they can do that by strengthening and regulating the rescue force structure, enhancing the skills and knowledge, training rescue workers

  20. Rainfall erosivity in the Fukushima Prefecture: implications for radiocesium mobilization and migration

    NASA Astrophysics Data System (ADS)

    Laceby, J. Patrick; Chartin, Caroline; Degan, Francesca; Onda, Yuichi; Evrard, Olivier; Cerdan, Olivier; Ayrault, Sophie

    2015-04-01

    The Fukushima Dai-ichi nuclear power plant (FDNPP) accident in March 2011 led to the fallout of predominantly radiocesium (137Cs and 134Cs) on soils of the Fukushima Prefecture. This radiocesium was primarily fixated to fine soil particles. Subsequently, rainfall and snow melt run-off events result in significant quantities of radiocesium being eroded and transported throughout the coastal catchments and ultimately exported to the Pacific Ocean. Erosion models, such as the Universal Soil Loss Equation (USLE), relate rainfall directly to soil erosion in that an increase in rainfall one month will directly result in a proportional increase in sediment generation. Understanding the rainfall regime of the region is therefore fundamental to modelling and predicting long-term radiocesium export. Here, we analyze rainfall data for ~40 stations within a 100 km radius of the FDNPP. First we present general information on the rainfall regime in the region based on monthly and annual rainfall totals. Second we present general information on rainfall erosivity, the R-factor of the USLE equation and its relationship to the general rainfall data. Third we examine rainfall trends over the last 100 years at several of the rainfall stations to understand temporal trends and whether ~20 years of data is sufficient to calculate the R-factor for USLE models. Fourth we present monthly R-factor maps for the Fukushima coastal catchments impacted by the FDNPP accident. The variability of the rainfall in the region, particularly during the typhoon season, is likely resulting in a similar variability in the transfer and migration of radiocesium throughout the coastal catchments of the Fukushima Prefecture. Characterizing the region's rainfall variability is fundamental to modelling sediment and the concomitant radiocesium migration and transfer throughout these catchments and ultimately to the Pacific Ocean.

  1. Simulating Earthquakes for Science and Society: New Earthquake Visualizations Ideal for Use in Science Communication

    NASA Astrophysics Data System (ADS)

    de Groot, R. M.; Benthien, M. L.

    2006-12-01

    The Southern California Earthquake Center (SCEC) has been developing groundbreaking computer modeling capabilities for studying earthquakes. These visualizations were initially shared within the scientific community but have recently have gained visibility via television news coverage in Southern California. These types of visualizations are becoming pervasive in the teaching and learning of concepts related to earth science. Computers have opened up a whole new world for scientists working with large data sets, and students can benefit from the same opportunities (Libarkin &Brick, 2002). Earthquakes are ideal candidates for visualization products: they cannot be predicted, are completed in a matter of seconds, occur deep in the earth, and the time between events can be on a geologic time scale. For example, the southern part of the San Andreas fault has not seen a major earthquake since about 1690, setting the stage for an earthquake as large as magnitude 7.7 -- the "big one." Since no one has experienced such an earthquake, visualizations can help people understand the scale of such an event. Accordingly, SCEC has developed a revolutionary simulation of this earthquake, with breathtaking visualizations that are now being distributed. According to Gordin and Pea (1995), theoretically visualization should make science accessible, provide means for authentic inquiry, and lay the groundwork to understand and critique scientific issues. This presentation will discuss how the new SCEC visualizations and other earthquake imagery achieve these results, how they fit within the context of major themes and study areas in science communication, and how the efficacy of these tools can be improved.

  2. Earthquake number forecasts testing

    NASA Astrophysics Data System (ADS)

    Kagan, Yan Y.

    2017-10-01

    We study the distributions of earthquake numbers in two global earthquake catalogues: Global Centroid-Moment Tensor and Preliminary Determinations of Epicenters. The properties of these distributions are especially required to develop the number test for our forecasts of future seismic activity rate, tested by the Collaboratory for Study of Earthquake Predictability (CSEP). A common assumption, as used in the CSEP tests, is that the numbers are described by the Poisson distribution. It is clear, however, that the Poisson assumption for the earthquake number distribution is incorrect, especially for the catalogues with a lower magnitude threshold. In contrast to the one-parameter Poisson distribution so widely used to describe earthquake occurrences, the negative-binomial distribution (NBD) has two parameters. The second parameter can be used to characterize the clustering or overdispersion of a process. We also introduce and study a more complex three-parameter beta negative-binomial distribution. We investigate the dependence of parameters for both Poisson and NBD distributions on the catalogue magnitude threshold and on temporal subdivision of catalogue duration. First, we study whether the Poisson law can be statistically rejected for various catalogue subdivisions. We find that for most cases of interest, the Poisson distribution can be shown to be rejected statistically at a high significance level in favour of the NBD. Thereafter, we investigate whether these distributions fit the observed distributions of seismicity. For this purpose, we study upper statistical moments of earthquake numbers (skewness and kurtosis) and compare them to the theoretical values for both distributions. Empirical values for the skewness and the kurtosis increase for the smaller magnitude threshold and increase with even greater intensity for small temporal subdivision of catalogues. The Poisson distribution for large rate values approaches the Gaussian law, therefore its skewness

  3. Proposal as to Efficient Collection and Exploitation of Earthquake Damage Information and Verification by Field Experiment at Toyohashi City

    NASA Astrophysics Data System (ADS)

    Zama, Shinsaku; Endo, Makoto; Takanashi, Ken'ichi; Araiba, Kiminori; Sekizawa, Ai; Hosokawa, Masafumi; Jeong, Byeong-Pyo; Hisada, Yoshiaki; Murakami, Masahiro

    Based on the earlier study result that the gathering of damage information can be quickly achieved in a municipality with a smaller population, it is proposed that damage information is gathered and analyzed using an area roughly equivalent to a primary school district as a basic unit. The introduction of this type of decentralized system is expected to quickly gather important information on each area. The information gathered by these communal disaster prevention bases is sent to the disaster prevention headquarters which in turn feeds back more extensive information over a wider area to the communal disaster prevention bases. Concrete systems have been developed according to the above mentioned framework, and we performed large-scale experiments on simulating disaster information collection, transmission and on utilization for smooth responses against earthquake disaster with collaboration from Toyohashi City, Aichi Prefecture, where is considered to suffer extensive damage from the Tokai and Tonankai Earthquakes with very high probability of the occurrence. Using disaster information collection/transmission equipments composed of long-distance wireless LAN, a notebook computer, a Web camera and an IP telephone, city staffs could easily input and transmit the information such as fire, collapsed houses and impassable roads, which were collected by the inhabitants participated in the experiment. Headquarters could confirm such information on the map automatically plotted, and also state of each disaster-prevention facility by means of Web-cameras and IP telephones. Based on the damage information, fire-spreading, evaluation, and traffic simulations were automatically executed at the disaster countermeasure office and their results were displayed on the large screen to utilize for making decisions such as residents' evacuation. These simulated results were simultaneously displayed at each disaster-prevention facility and were served to make people understand the

  4. Earthquake nucleation by transient deformations caused by the M = 7.9 Denali, Alaska, earthquake

    USGS Publications Warehouse

    Gomberg, J.; Bodin, P.; Larson, K.; Dragert, H.

    2004-01-01

    The permanent and dynamic (transient) stress changes inferred to trigger earthquakes are usually orders of magnitude smaller than the stresses relaxed by the earthquakes themselves, implying that triggering occurs on critically stressed faults. Triggered seismicity rate increases may therefore be most likely to occur in areas where loading rates are highest and elevated pore pressures, perhaps facilitated by high-temperature fluids, reduce frictional stresses and promote failure. Here we show that the 2002 magnitude M = 7.9 Denali, Alaska, earthquake triggered wide-spread seismicity rate increases throughout British Columbia and into the western United States. Dynamic triggering by seismic waves should be enhanced in directions where rupture directivity focuses radiated energy, and we verify this using seismic and new high-sample GPS recordings of the Denali mainshock. These observations are comparable in scale only to the triggering caused by the 1992 M = 7.4 Landers, California, earthquake, and demonstrate that Landers triggering did not reflect some peculiarity of the region or the earthquake. However, the rate increases triggered by the Denali earthquake occurred in areas not obviously tectonically active, implying that even in areas of low ambient stressing rates, faults may still be critically stressed and that dynamic triggering may be ubiquitous and unpredictable.

  5. Prediction of earthquake-triggered landslide event sizes

    NASA Astrophysics Data System (ADS)

    Braun, Anika; Havenith, Hans-Balder; Schlögel, Romy

    2016-04-01

    Seismically induced landslides are a major environmental effect of earthquakes, which may significantly contribute to related losses. Moreover, in paleoseismology landslide event sizes are an important proxy for the estimation of the intensity and magnitude of past earthquakes and thus allowing us to improve seismic hazard assessment over longer terms. Not only earthquake intensity, but also factors such as the fault characteristics, topography, climatic conditions and the geological environment have a major impact on the intensity and spatial distribution of earthquake induced landslides. We present here a review of factors contributing to earthquake triggered slope failures based on an "event-by-event" classification approach. The objective of this analysis is to enable the short-term prediction of earthquake triggered landslide event sizes in terms of numbers and size of the affected area right after an earthquake event occurred. Five main factors, 'Intensity', 'Fault', 'Topographic energy', 'Climatic conditions' and 'Surface geology' were used to establish a relationship to the number and spatial extend of landslides triggered by an earthquake. The relative weight of these factors was extracted from published data for numerous past earthquakes; topographic inputs were checked in Google Earth and through geographic information systems. Based on well-documented recent earthquakes (e.g. Haiti 2010, Wenchuan 2008) and on older events for which reliable extensive information was available (e.g. Northridge 1994, Loma Prieta 1989, Guatemala 1976, Peru 1970) the combination and relative weight of the factors was calibrated. The calibrated factor combination was then applied to more than 20 earthquake events for which landslide distribution characteristics could be cross-checked. One of our main findings is that the 'Fault' factor, which is based on characteristics of the fault, the surface rupture and its location with respect to mountain areas, has the most important

  6. Applicability of source scaling relations for crustal earthquakes to estimation of the ground motions of the 2016 Kumamoto earthquake

    NASA Astrophysics Data System (ADS)

    Irikura, Kojiro; Miyakoshi, Ken; Kamae, Katsuhiro; Yoshida, Kunikazu; Somei, Kazuhiro; Kurahashi, Susumu; Miyake, Hiroe

    2017-01-01

    A two-stage scaling relationship of the source parameters for crustal earthquakes in Japan has previously been constructed, in which source parameters obtained from the results of waveform inversion of strong motion data are combined with parameters estimated based on geological and geomorphological surveys. A three-stage scaling relationship was subsequently developed to extend scaling to crustal earthquakes with magnitudes greater than M w 7.4. The effectiveness of these scaling relationships was then examined based on the results of waveform inversion of 18 recent crustal earthquakes ( M w 5.4-6.9) that occurred in Japan since the 1995 Hyogo-ken Nanbu earthquake. The 2016 Kumamoto earthquake, with M w 7.0, was one of the largest earthquakes to occur since dense and accurate strong motion observation networks, such as K-NET and KiK-net, were deployed after the 1995 Hyogo-ken Nanbu earthquake. We examined the applicability of the scaling relationships of the source parameters of crustal earthquakes in Japan to the 2016 Kumamoto earthquake. The rupture area and asperity area were determined based on slip distributions obtained from waveform inversion of the 2016 Kumamoto earthquake observations. We found that the relationship between the rupture area and the seismic moment for the 2016 Kumamoto earthquake follows the second-stage scaling within one standard deviation ( σ = 0.14). The ratio of the asperity area to the rupture area for the 2016 Kumamoto earthquake is nearly the same as ratios previously obtained for crustal earthquakes. Furthermore, we simulated the ground motions of this earthquake using a characterized source model consisting of strong motion generation areas (SMGAs) based on the empirical Green's function (EGF) method. The locations and areas of the SMGAs were determined through comparison between the synthetic ground motions and observed motions. The sizes of the SMGAs were nearly coincident with the asperities with large slip. The synthetic

  7. Evidence for Ancient Mesoamerican Earthquakes

    NASA Astrophysics Data System (ADS)

    Kovach, R. L.; Garcia, B.

    2001-12-01

    Evidence for past earthquake damage at Mesoamerican ruins is often overlooked because of the invasive effects of tropical vegetation and is usually not considered as a casual factor when restoration and reconstruction of many archaeological sites are undertaken. Yet the proximity of many ruins to zones of seismic activity would argue otherwise. Clues as to the types of damage which should be soughtwere offered in September 1999 when the M = 7.5 Oaxaca earthquake struck the ruins of Monte Alban, Mexico, where archaeological renovations were underway. More than 20 structures were damaged, 5 of them seriously. Damage features noted were walls out of plumb, fractures in walls, floors, basal platforms and tableros, toppling of columns, and deformation, settling and tumbling of walls. A Modified Mercalli Intensity of VII (ground accelerations 18-34 %b) occurred at the site. Within the diffuse landward extension of the Caribbean plate boundary zone M = 7+ earthquakes occur with repeat times of hundreds of years arguing that many Maya sites were subjected to earthquakes. Damage to re-erected and reinforced stelae, walls, and buildings were witnessed at Quirigua, Guatemala, during an expedition underway when then 1976 M = 7.5 Guatemala earthquake on the Motagua fault struck. Excavations also revealed evidence (domestic pttery vessels and skeleton of a child crushed under fallen walls) of an ancient earthquake occurring about the teim of the demise and abandonment of Quirigua in the late 9th century. Striking evidence for sudden earthquake building collapse at the end of the Mayan Classic Period ~A.D. 889 was found at Benque Viejo (Xunantunich), Belize, located 210 north of Quirigua. It is argued that a M = 7.5 to 7.9 earthquake at the end of the Maya Classic period centered in the vicinity of the Chixoy-Polochic and Motagua fault zones cound have produced the contemporaneous earthquake damage to the above sites. As a consequences this earthquake may have accelerated the

  8. Earthquake Potential Models for China

    NASA Astrophysics Data System (ADS)

    Rong, Y.; Jackson, D. D.

    2002-12-01

    We present three earthquake potential estimates for magnitude 5.4 and larger earthquakes for China. The potential is expressed as the rate density (probability per unit area, magnitude and time). The three methods employ smoothed seismicity-, geologic slip rate-, and geodetic strain rate data. We tested all three estimates, and the published Global Seismic Hazard Assessment Project (GSHAP) model, against earthquake data. We constructed a special earthquake catalog which combines previous catalogs covering different times. We used the special catalog to construct our smoothed seismicity model and to evaluate all models retrospectively. All our models employ a modified Gutenberg-Richter magnitude distribution with three parameters: a multiplicative ``a-value," the slope or ``b-value," and a ``corner magnitude" marking a strong decrease of earthquake rate with magnitude. We assumed the b-value to be constant for the whole study area and estimated the other parameters from regional or local geophysical data. The smoothed seismicity method assumes that the rate density is proportional to the magnitude of past earthquakes and approximately as the reciprocal of the epicentral distance out to a few hundred kilometers. We derived the upper magnitude limit from the special catalog and estimated local a-values from smoothed seismicity. Earthquakes since January 1, 2000 are quite compatible with the model. For the geologic forecast we adopted the seismic source zones (based on geological, geodetic and seismicity data) of the GSHAP model. For each zone, we estimated a corner magnitude by applying the Wells and Coppersmith [1994] relationship to the longest fault in the zone, and we determined the a-value from fault slip rates and an assumed locking depth. The geological model fits the earthquake data better than the GSHAP model. We also applied the Wells and Coppersmith relationship to individual faults, but the results conflicted with the earthquake record. For our geodetic

  9. Post-earthquake building safety assessments for the Canterbury Earthquakes

    USGS Publications Warehouse

    Marshall, J.; Barnes, J.; Gould, N.; Jaiswal, K.; Lizundia, B.; Swanson, David A.; Turner, F.

    2012-01-01

    This paper explores the post-earthquake building assessment program that was utilized in Christchurch, New Zealand following the Canterbury Sequence of earthquakes beginning with the Magnitude (Mw.) 7.1 Darfield event in September 2010. The aftershocks or triggered events, two of which exceeded Mw 6.0, continued with events in February and June 2011 causing the greatest amount of damage. More than 70,000 building safety assessments were completed following the February event. The timeline and assessment procedures will be discussed including the use of rapid response teams, selection of indicator buildings to monitor damage following aftershocks, risk assessments for demolition of red-tagged buildings, the use of task forces to address management of the heavily damaged downtown area and the process of demolition. Through the post-event safety assessment program that occurred throughout the Canterbury Sequence of earthquakes, many important lessons can be learned that will benefit future response to natural hazards that have potential to damage structures.

  10. Testing earthquake source inversion methodologies

    USGS Publications Warehouse

    Page, M.; Mai, P.M.; Schorlemmer, D.

    2011-01-01

    Source Inversion Validation Workshop; Palm Springs, California, 11-12 September 2010; Nowadays earthquake source inversions are routinely performed after large earthquakes and represent a key connection between recorded seismic and geodetic data and the complex rupture process at depth. The resulting earthquake source models quantify the spatiotemporal evolution of ruptures. They are also used to provide a rapid assessment of the severity of an earthquake and to estimate losses. However, because of uncertainties in the data, assumed fault geometry and velocity structure, and chosen rupture parameterization, it is not clear which features of these source models are robust. Improved understanding of the uncertainty and reliability of earthquake source inversions will allow the scientific community to use the robust features of kinematic inversions to more thoroughly investigate the complexity of the rupture process and to better constrain other earthquakerelated computations, such as ground motion simulations and static stress change calculations.

  11. Testing an earthquake prediction algorithm

    USGS Publications Warehouse

    Kossobokov, V.G.; Healy, J.H.; Dewey, J.W.

    1997-01-01

    A test to evaluate earthquake prediction algorithms is being applied to a Russian algorithm known as M8. The M8 algorithm makes intermediate term predictions for earthquakes to occur in a large circle, based on integral counts of transient seismicity in the circle. In a retroactive prediction for the period January 1, 1985 to July 1, 1991 the algorithm as configured for the forward test would have predicted eight of ten strong earthquakes in the test area. A null hypothesis, based on random assignment of predictions, predicts eight earthquakes in 2.87% of the trials. The forward test began July 1, 1991 and will run through December 31, 1997. As of July 1, 1995, the algorithm had forward predicted five out of nine earthquakes in the test area, which success ratio would have been achieved in 53% of random trials with the null hypothesis.

  12. Earthquakes, July-August, 1979

    USGS Publications Warehouse

    Person, W.J.

    1980-01-01

    In the United States, on August 6, central California experienced a moderately strong earthquake, which injured several people and caused some damage. A number of earthquakes occurred in other parts of the United States but caused very little damage. 

  13. Earthquake cycles and physical modeling of the process leading up to a large earthquake

    NASA Astrophysics Data System (ADS)

    Ohnaka, Mitiyasu

    2004-08-01

    A thorough discussion is made on what the rational constitutive law for earthquake ruptures ought to be from the standpoint of the physics of rock friction and fracture on the basis of solid facts observed in the laboratory. From this standpoint, it is concluded that the constitutive law should be a slip-dependent law with parameters that may depend on slip rate or time. With the long-term goal of establishing a rational methodology of forecasting large earthquakes, the entire process of one cycle for a typical, large earthquake is modeled, and a comprehensive scenario that unifies individual models for intermediate-and short-term (immediate) forecasts is presented within the framework based on the slip-dependent constitutive law and the earthquake cycle model. The earthquake cycle includes the phase of accumulation of elastic strain energy with tectonic loading (phase II), and the phase of rupture nucleation at the critical stage where an adequate amount of the elastic strain energy has been stored (phase III). Phase II plays a critical role in physical modeling of intermediate-term forecasting, and phase III in physical modeling of short-term (immediate) forecasting. The seismogenic layer and individual faults therein are inhomogeneous, and some of the physical quantities inherent in earthquake ruptures exhibit scale-dependence. It is therefore critically important to incorporate the properties of inhomogeneity and physical scaling, in order to construct realistic, unified scenarios with predictive capability. The scenario presented may be significant and useful as a necessary first step for establishing the methodology for forecasting large earthquakes.

  14. Mega-earthquakes rupture flat megathrusts.

    PubMed

    Bletery, Quentin; Thomas, Amanda M; Rempel, Alan W; Karlstrom, Leif; Sladen, Anthony; De Barros, Louis

    2016-11-25

    The 2004 Sumatra-Andaman and 2011 Tohoku-Oki earthquakes highlighted gaps in our understanding of mega-earthquake rupture processes and the factors controlling their global distribution: A fast convergence rate and young buoyant lithosphere are not required to produce mega-earthquakes. We calculated the curvature along the major subduction zones of the world, showing that mega-earthquakes preferentially rupture flat (low-curvature) interfaces. A simplified analytic model demonstrates that heterogeneity in shear strength increases with curvature. Shear strength on flat megathrusts is more homogeneous, and hence more likely to be exceeded simultaneously over large areas, than on highly curved faults. Copyright © 2016, American Association for the Advancement of Science.

  15. The USGS Earthquake Notification Service (ENS): Customizable notifications of earthquakes around the globe

    USGS Publications Warehouse

    Wald, Lisa A.; Wald, David J.; Schwarz, Stan; Presgrave, Bruce; Earle, Paul S.; Martinez, Eric; Oppenheimer, David

    2008-01-01

    At the beginning of 2006, the U.S. Geological Survey (USGS) Earthquake Hazards Program (EHP) introduced a new automated Earthquake Notification Service (ENS) to take the place of the National Earthquake Information Center (NEIC) "Bigquake" system and the various other individual EHP e-mail list-servers for separate regions in the United States. These included northern California, southern California, and the central and eastern United States. ENS is a "one-stop shopping" system that allows Internet users to subscribe to flexible and customizable notifications for earthquakes anywhere in the world. The customization capability allows users to define the what (magnitude threshold), the when (day and night thresholds), and the where (specific regions) for their notifications. Customization is achieved by employing a per-user based request profile, allowing the notifications to be tailored for each individual's requirements. Such earthquake-parameter-specific custom delivery was not possible with simple e-mail list-servers. Now that event and user profiles are in a structured query language (SQL) database, additional flexibility is possible. At the time of this writing, ENS had more than 114,000 subscribers, with more than 200,000 separate user profiles. On a typical day, more than 188,000 messages get sent to a variety of widely distributed users for a wide range of earthquake locations and magnitudes. The purpose of this article is to describe how ENS works, highlight the features it offers, and summarize plans for future developments.

  16. A note on evaluating VAN earthquake predictions

    NASA Astrophysics Data System (ADS)

    Tselentis, G.-Akis; Melis, Nicos S.

    The evaluation of the success level of an earthquake prediction method should not be based on approaches that apply generalized strict statistical laws and avoid the specific nature of the earthquake phenomenon. Fault rupture processes cannot be compared to gambling processes. The outcome of the present note is that even an ideal earthquake prediction method is still shown to be a matter of a “chancy” association between precursors and earthquakes if we apply the same procedure proposed by Mulargia and Gasperini [1992] in evaluating VAN earthquake predictions. Each individual VAN prediction has to be evaluated separately, taking always into account the specific circumstances and information available. The success level of epicenter prediction should depend on the earthquake magnitude, and magnitude and time predictions may depend on earthquake clustering and the tectonic regime respectively.

  17. Strategies for rapid global earthquake impact estimation: the Prompt Assessment of Global Earthquakes for Response (PAGER) system

    USGS Publications Warehouse

    Jaiswal, Kishor; Wald, D.J.

    2013-01-01

    This chapter summarizes the state-of-the-art for rapid earthquake impact estimation. It details the needs and challenges associated with quick estimation of earthquake losses following global earthquakes, and provides a brief literature review of various approaches that have been used in the past. With this background, the chapter introduces the operational earthquake loss estimation system developed by the U.S. Geological Survey (USGS) known as PAGER (for Prompt Assessment of Global Earthquakes for Response). It also details some of the ongoing developments of PAGER’s loss estimation models to better supplement the operational empirical models, and to produce value-added web content for a variety of PAGER users.

  18. Stigma in science: the case of earthquake prediction.

    PubMed

    Joffe, Helene; Rossetto, Tiziana; Bradley, Caroline; O'Connor, Cliodhna

    2018-01-01

    This paper explores how earthquake scientists conceptualise earthquake prediction, particularly given the conviction of six earthquake scientists for manslaughter (subsequently overturned) on 22 October 2012 for having given inappropriate advice to the public prior to the L'Aquila earthquake of 6 April 2009. In the first study of its kind, semi-structured interviews were conducted with 17 earthquake scientists and the transcribed interviews were analysed thematically. The scientists primarily denigrated earthquake prediction, showing strong emotive responses and distancing themselves from earthquake 'prediction' in favour of 'forecasting'. Earthquake prediction was regarded as impossible and harmful. The stigmatisation of the subject is discussed in the light of research on boundary work and stigma in science. The evaluation reveals how mitigation becomes the more favoured endeavour, creating a normative environment that disadvantages those who continue to pursue earthquake prediction research. Recommendations are made for communication with the public on earthquake risk, with a focus on how scientists portray uncertainty. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.

  19. Insignificant solar-terrestrial triggering of earthquakes

    USGS Publications Warehouse

    Love, Jeffrey J.; Thomas, Jeremy N.

    2013-01-01

    We examine the claim that solar-terrestrial interaction, as measured by sunspots, solar wind velocity, and geomagnetic activity, might play a role in triggering earthquakes. We count the number of earthquakes having magnitudes that exceed chosen thresholds in calendar years, months, and days, and we order these counts by the corresponding rank of annual, monthly, and daily averages of the solar-terrestrial variables. We measure the statistical significance of the difference between the earthquake-number distributions below and above the median of the solar-terrestrial averages by χ2 and Student's t tests. Across a range of earthquake magnitude thresholds, we find no consistent and statistically significant distributional differences. We also introduce time lags between the solar-terrestrial variables and the number of earthquakes, but again no statistically significant distributional difference is found. We cannot reject the null hypothesis of no solar-terrestrial triggering of earthquakes.

  20. Laboratory investigations of earthquake dynamics

    NASA Astrophysics Data System (ADS)

    Xia, Kaiwen

    In this thesis this will be attempted through controlled laboratory experiments that are designed to mimic natural earthquake scenarios. The earthquake dynamic rupturing process itself is a complicated phenomenon, involving dynamic friction, wave propagation, and heat production. Because controlled experiments can produce results without assumptions needed in theoretical and numerical analysis, the experimental method is thus advantageous over theoretical and numerical methods. Our laboratory fault is composed of carefully cut photoelastic polymer plates (Homahte-100, Polycarbonate) held together by uniaxial compression. As a unique unit of the experimental design, a controlled exploding wire technique provides the triggering mechanism of laboratory earthquakes. Three important components of real earthquakes (i.e., pre-existing fault, tectonic loading, and triggering mechanism) correspond to and are simulated by frictional contact, uniaxial compression, and the exploding wire technique. Dynamic rupturing processes are visualized using the photoelastic method and are recorded via a high-speed camera. Our experimental methodology, which is full-field, in situ, and non-intrusive, has better control and diagnostic capacity compared to other existing experimental methods. Using this experimental approach, we have investigated several problems: dynamics of earthquake faulting occurring along homogeneous faults separating identical materials, earthquake faulting along inhomogeneous faults separating materials with different wave speeds, and earthquake faulting along faults with a finite low wave speed fault core. We have observed supershear ruptures, subRayleigh to supershear rupture transition, crack-like to pulse-like rupture transition, self-healing (Heaton) pulse, and rupture directionality.

  1. Physics of Earthquake Rupture Propagation

    NASA Astrophysics Data System (ADS)

    Xu, Shiqing; Fukuyama, Eiichi; Sagy, Amir; Doan, Mai-Linh

    2018-05-01

    A comprehensive understanding of earthquake rupture propagation requires the study of not only the sudden release of elastic strain energy during co-seismic slip, but also of other processes that operate at a variety of spatiotemporal scales. For example, the accumulation of the elastic strain energy usually takes decades to hundreds of years, and rupture propagation and termination modify the bulk properties of the surrounding medium that can influence the behavior of future earthquakes. To share recent findings in the multiscale investigation of earthquake rupture propagation, we held a session entitled "Physics of Earthquake Rupture Propagation" during the 2016 American Geophysical Union (AGU) Fall Meeting in San Francisco. The session included 46 poster and 32 oral presentations, reporting observations of natural earthquakes, numerical and experimental simulations of earthquake ruptures, and studies of earthquake fault friction. These presentations and discussions during and after the session suggested a need to document more formally the research findings, particularly new observations and views different from conventional ones, complexities in fault zone properties and loading conditions, the diversity of fault slip modes and their interactions, the evaluation of observational and model uncertainties, and comparison between empirical and physics-based models. Therefore, we organize this Special Issue (SI) of Tectonophysics under the same title as our AGU session, hoping to inspire future investigations. Eighteen articles (marked with "this issue") are included in this SI and grouped into the following six categories.

  2. Real Time Earthquake Information System in Japan

    NASA Astrophysics Data System (ADS)

    Doi, K.; Kato, T.

    2003-12-01

    An early earthquake notification system in Japan had been developed by the Japan Meteorological Agency (JMA) as a governmental organization responsible for issuing earthquake information and tsunami forecasts. The system was primarily developed for prompt provision of a tsunami forecast to the public with locating an earthquake and estimating its magnitude as quickly as possible. Years after, a system for a prompt provision of seismic intensity information as indices of degrees of disasters caused by strong ground motion was also developed so that concerned governmental organizations can decide whether it was necessary for them to launch emergency response or not. At present, JMA issues the following kinds of information successively when a large earthquake occurs. 1) Prompt report of occurrence of a large earthquake and major seismic intensities caused by the earthquake in about two minutes after the earthquake occurrence. 2) Tsunami forecast in around three minutes. 3) Information on expected arrival times and maximum heights of tsunami waves in around five minutes. 4) Information on a hypocenter and a magnitude of the earthquake, the seismic intensity at each observation station, the times of high tides in addition to the expected tsunami arrival times in 5-7 minutes. To issue information above, JMA has established; - An advanced nationwide seismic network with about 180 stations for seismic wave observation and about 3,400 stations for instrumental seismic intensity observation including about 2,800 seismic intensity stations maintained by local governments, - Data telemetry networks via landlines and partly via a satellite communication link, - Real-time data processing techniques, for example, the automatic calculation of earthquake location and magnitude, the database driven method for quantitative tsunami estimation, and - Dissemination networks, via computer-to-computer communications and facsimile through dedicated telephone lines. JMA operationally

  3. Earthquake precursory events around epicenters and local active faults; the cases of two inland earthquakes in Iran

    NASA Astrophysics Data System (ADS)

    Valizadeh Alvan, H.; Mansor, S.; Haydari Azad, F.

    2012-12-01

    The possibility of earthquake prediction in the frame of several days to few minutes before its occurrence has stirred interest among researchers, recently. Scientists believe that the new theories and explanations of the mechanism of this natural phenomenon are trustable and can be the basis of future prediction efforts. During the last thirty years experimental researches resulted in some pre-earthquake events which are now recognized as confirmed warning signs (precursors) of past known earthquakes. With the advances in in-situ measurement devices and data analysis capabilities and the emergence of satellite-based data collectors, monitoring the earth's surface is now a regular work. Data providers are supplying researchers from all over the world with high quality and validated imagery and non-imagery data. Surface Latent Heat Flux (SLHF) or the amount of energy exchange in the form of water vapor between the earth's surface and atmosphere has been frequently reported as an earthquake precursor during the past years. The accumulated stress in the earth's crust during the preparation phase of earthquakes is said to be the main cause of temperature anomalies weeks to days before the main event and subsequent shakes. Chemical and physical interactions in the presence of underground water lead to higher water evaporation prior to inland earthquakes. On the other hand, the leak of Radon gas occurred as rocks break during earthquake preparation causes the formation of airborne ions and higher Air Temperature (AT) prior to main event. Although co-analysis of direct and indirect observation for precursory events is considered as a promising method for future successful earthquake prediction, without proper and thorough knowledge about the geological setting, atmospheric factors and geodynamics of the earthquake-prone regions we will not be able to identify anomalies due to seismic activity in the earth's crust. Active faulting is a key factor in identification of the

  4. Historical and recent large megathrust earthquakes in Chile

    NASA Astrophysics Data System (ADS)

    Ruiz, S.; Madariaga, R.

    2018-05-01

    Recent earthquakes in Chile, 2014, Mw 8.2 Iquique, 2015, Mw 8.3 Illapel and 2016, Mw 7.6 Chiloé have put in evidence some problems with the straightforward application of ideas about seismic gaps, earthquake periodicity and the general forecast of large megathrust earthquakes. In northern Chile, before the 2014 Iquique earthquake 4 large earthquakes were reported in written chronicles, 1877, 1786, 1615 and 1543; in North-Central Chile, before the 2015 Illapel event, 3 large earthquakes 1943, 1880, 1730 were reported; and the 2016 Chiloé earthquake occurred in the southern zone of the 1960 Valdivia megathrust rupture, where other large earthquakes occurred in 1575, 1737 and 1837. The periodicity of these events has been proposed as a good long-term forecasting. However, the seismological aspects of historical Chilean earthquakes were inferred mainly from old chronicles written before subduction in Chile was discovered. Here we use the original description of earthquakes to re-analyze the historical archives. Our interpretation shows that a-priori ideas, like seismic gaps and characteristic earthquakes, influenced the estimation of magnitude, location and rupture area of the older Chilean events. On the other hand, the advance in the characterization of the rheological aspects that controlled the contact between Nazca and South-American plate and the study of tsunami effects provide better estimations of the location of historical earthquakes along the seismogenic plate interface. Our re-interpretation of historical earthquakes shows a large diversity of earthquakes types; there is a major difference between giant earthquakes that break the entire plate interface and those of Mw 8.0 that only break a portion of it.

  5. Volcano-earthquake interaction at Mauna Loa volcano, Hawaii

    NASA Astrophysics Data System (ADS)

    Walter, Thomas R.; Amelung, Falk

    2006-05-01

    The activity at Mauna Loa volcano, Hawaii, is characterized by eruptive fissures that propagate into the Southwest Rift Zone (SWRZ) or into the Northeast Rift Zone (NERZ) and by large earthquakes at the basal decollement fault. In this paper we examine the historic eruption and earthquake catalogues, and we test the hypothesis that the events are interconnected in time and space. Earthquakes in the Kaoiki area occur in sequence with eruptions from the NERZ, and earthquakes in the Kona and Hilea areas occur in sequence with eruptions from the SWRZ. Using three-dimensional numerical models, we demonstrate that elastic stress transfer can explain the observed volcano-earthquake interaction. We examine stress changes due to typical intrusions and earthquakes. We find that intrusions change the Coulomb failure stress along the decollement fault so that NERZ intrusions encourage Kaoiki earthquakes and SWRZ intrusions encourage Kona and Hilea earthquakes. On the other hand, earthquakes decompress the magma chamber and unclamp part of the Mauna Loa rift zone, i.e., Kaoiki earthquakes encourage NERZ intrusions, whereas Kona and Hilea earthquakes encourage SWRZ intrusions. We discuss how changes of the static stress field affect the occurrence of earthquakes as well as the occurrence, location, and volume of dikes and of associated eruptions and also the lava composition and fumarolic activity.

  6. Seismicity in the source areas of the 1896 and 1933 Sanriku earthquakes and implications for large near-trench earthquake faults

    NASA Astrophysics Data System (ADS)

    Obana, Koichiro; Nakamura, Yasuyuki; Fujie, Gou; Kodaira, Shuichi; Kaiho, Yuka; Yamamoto, Yojiro; Miura, Seiichi

    2018-03-01

    In the northern part of the Japan Trench, the 1933 Showa-Sanriku earthquake (Mw 8.4), an outer-trench, normal-faulting earthquake, occurred 37 yr after the 1896 Meiji-Sanriku tsunami earthquake (Mw 8.0), a shallow, near-trench, plate-interface rupture. Tsunamis generated by both earthquakes caused severe damage along the Sanriku coast. Precise locations of earthquakes in the source areas of the 1896 and 1933 earthquakes have not previously been obtained because they occurred at considerable distances from the coast in deep water beyond the maximum operational depth of conventional ocean bottom seismographs (OBSs). In 2015, we incorporated OBSs designed for operation in deep water (ultradeep OBSs) in an OBS array during two months of seismic observations in the source areas of the 1896 and 1933 Sanriku earthquakes to investigate the relationship of seismicity there to outer-rise normal-faulting earthquakes and near-trench tsunami earthquakes. Our analysis showed that seismicity during our observation period occurred along three roughly linear trench-parallel trends in the outer-trench region. Seismic activity along these trends likely corresponds to aftershocks of the 1933 Showa-Sanriku earthquake and the Mw 7.4 normal-faulting earthquake that occurred 40 min after the 2011 Tohoku-Oki earthquake. Furthermore, changes of the clarity of reflections from the oceanic Moho on seismic reflection profiles and low-velocity anomalies within the oceanic mantle were observed near the linear trends of the seismicity. The focal mechanisms we determined indicate that an extensional stress regime extends to about 40 km depth, below which the stress regime is compressional. These observations suggest that rupture during the 1933 Showa-Sanriku earthquake did not extend to the base of the oceanic lithosphere and that compound rupture of multiple or segmented faults is a more plausible explanation for that earthquake. The source area of the 1896 Meiji-Sanriku tsunami earthquake is

  7. Influence of the great East Japan earthquake and tsunami 2011 on occurrence of cerebrovascular diseases in Iwate, Japan.

    PubMed

    Omama, Shinichi; Yoshida, Yuki; Ogasawara, Kuniaki; Ogawa, Akira; Ishibashi, Yasuhiro; Nakamura, Motoyuki; Tanno, Kozo; Ohsawa, Masaki; Onoda, Toshiyuki; Itai, Kazuyoshi; Sakata, Kiyomi

    2013-06-01

    Little information is available regarding the occurrence of cerebrovascular diseases after tsunamis. This study was performed to determine the influence of the tsunami damage caused by the Great East Japan earthquake on occurrence of cerebrovascular diseases. Subjects from the coastline and inland areas of Iwate Prefecture who developed cerebrovascular diseases before and after the disaster were included in the analysis. Standardized incidence ratios of 2011 against the previous 3 years were calculated in two 4-week periods before and four 4-week periods after the disaster, according to stroke subtype, sex, age group, and flood damage. The standard incidence ratio for cerebrovascular diseases was 1.20 (1.00-1.40) in the first 4-week period after the disaster and was not significant in other periods. The standard incidence ratios in the first 4-week period for cerebral infarction, intracerebral hemorrhage, and subarachnoid hemorrhage were 1.22 (0.98-1.46), 1.15 (0.76-1.55), and 1.20 (0.52-1.88), respectively. These values were 1.51 (1.19-1.88) for men, 1.35 (1.06-1.64) for subjects aged ≥ 75 years, and 1.35 (1.06-1.64) for the high flooding areas. The standard incidence ratio of cerebral infarction in the first 4-week period for men aged ≥ 75 years in the high flooding areas was 2.34 (1.34-3.34). In the areas highly flooded by the tsunami caused by the Great East Japan earthquake, the occurrence of cerebral infarction among elderly men more than doubled in the first 4 weeks after the disaster.

  8. Earthquakes in the New Zealand Region.

    ERIC Educational Resources Information Center

    Wallace, Cleland

    1995-01-01

    Presents a thorough overview of earthquakes in New Zealand, discussing plate tectonics, seismic measurement, and historical occurrences. Includes 10 figures illustrating such aspects as earthquake distribution, intensity, and fissures in the continental crust. Tabular data includes a list of most destructive earthquakes and descriptive effects…

  9. Napa Earthquake impact on water systems

    NASA Astrophysics Data System (ADS)

    Wang, J.

    2014-12-01

    South Napa earthquake occurred in Napa, California on August 24 at 3am, local time, and the magnitude is 6.0. The earthquake was the largest in SF Bay Area since the 1989 Loma Prieta earthquake. Economic loss topped $ 1 billion. Wine makers cleaning up and estimated the damage on tourism. Around 15,000 cases of lovely cabernet were pouring into the garden at the Hess Collection. Earthquake potentially raise water pollution risks, could cause water crisis. CA suffered water shortage recent years, and it could be helpful on how to prevent underground/surface water pollution from earthquake. This research gives a clear view on drinking water system in CA, pollution on river systems, as well as estimation on earthquake impact on water supply. The Sacramento-San Joaquin River delta (close to Napa), is the center of the state's water distribution system, delivering fresh water to more than 25 million residents and 3 million acres of farmland. Delta water conveyed through a network of levees is crucial to Southern California. The drought has significantly curtailed water export, and salt water intrusion reduced fresh water outflows. Strong shaking from a nearby earthquake can cause saturated, loose, sandy soils liquefaction, and could potentially damage major delta levee systems near Napa. Napa earthquake is a wake-up call for Southern California. It could potentially damage freshwater supply system.

  10. Earthquake Hazard Analysis Methods: A Review

    NASA Astrophysics Data System (ADS)

    Sari, A. M.; Fakhrurrozi, A.

    2018-02-01

    One of natural disasters that have significantly impacted on risks and damage is an earthquake. World countries such as China, Japan, and Indonesia are countries located on the active movement of continental plates with more frequent earthquake occurrence compared to other countries. Several methods of earthquake hazard analysis have been done, for example by analyzing seismic zone and earthquake hazard micro-zonation, by using Neo-Deterministic Seismic Hazard Analysis (N-DSHA) method, and by using Remote Sensing. In its application, it is necessary to review the effectiveness of each technique in advance. Considering the efficiency of time and the accuracy of data, remote sensing is used as a reference to the assess earthquake hazard accurately and quickly as it only takes a limited time required in the right decision-making shortly after the disaster. Exposed areas and possibly vulnerable areas due to earthquake hazards can be easily analyzed using remote sensing. Technological developments in remote sensing such as GeoEye-1 provide added value and excellence in the use of remote sensing as one of the methods in the assessment of earthquake risk and damage. Furthermore, the use of this technique is expected to be considered in designing policies for disaster management in particular and can reduce the risk of natural disasters such as earthquakes in Indonesia.

  11. Acceleration spectra for subduction zone earthquakes

    USGS Publications Warehouse

    Boatwright, J.; Choy, G.L.

    1989-01-01

    We estimate the source spectra of shallow earthquakes from digital recordings of teleseismic P wave groups, that is, P+pP+sP, by making frequency dependent corrections for the attenuation and for the interference of the free surface. The correction for the interference of the free surface assumes that the earthquake radiates energy from a range of depths. We apply this spectral analysis to a set of 12 subduction zone earthquakes which range in size from Ms = 6.2 to 8.1, obtaining corrected P wave acceleration spectra on the frequency band from 0.01 to 2.0 Hz. Seismic moment estimates from surface waves and normal modes are used to extend these P wave spectra to the frequency band from 0.001 to 0.01 Hz. The acceleration spectra of large subduction zone earthquakes, that is, earthquakes whose seismic moments are greater than 1027 dyn cm, exhibit intermediate slopes where u(w)???w5/4 for frequencies from 0.005 to 0.05 Hz. For these earthquakes, spectral shape appears to be a discontinuous function of seismic moment. Using reasonable assumptions for the phase characteristics, we transform the spectral shape observed for large earthquakes into the time domain to fit Ekstrom's (1987) moment rate functions for the Ms=8.1 Michoacan earthquake of September 19, 1985, and the Ms=7.6 Michoacan aftershock of September 21, 1985. -from Authors

  12. Earthquake Drill using the Earthquake Early Warning System at an Elementary School

    NASA Astrophysics Data System (ADS)

    Oki, Satoko; Yazaki, Yoshiaki; Koketsu, Kazuki

    2010-05-01

    Japan frequently suffers from many kinds of disasters such as earthquakes, typhoons, floods, volcanic eruptions, and landslides. On average, we lose about 120 people a year due to natural hazards in this decade. Above all, earthquakes are noteworthy, since it may kill thousands of people in a moment like in Kobe in 1995. People know that we may have "a big one" some day as long as we live on this land and that what to do; retrofit houses, appliance heavy furniture to walls, add latches to kitchen cabinets, and prepare emergency packs. Yet most of them do not take the action, and result in the loss of many lives. It is only the victims that learn something from the earthquake, and it has never become the lore of the nations. One of the most essential ways to reduce the damage is to educate the general public to be able to make the sound decision on what to do at the moment when an earthquake hits. This will require the knowledge of the backgrounds of the on-going phenomenon. The Ministry of Education, Culture, Sports, Science and Technology (MEXT), therefore, offered for public subscription to choose several model areas to adopt scientific education to the local elementary schools. This presentation is the report of a year and half courses that we had at the model elementary school in Tokyo Metropolitan Area. The tectonic setting of this area is very complicated; there are the Pacific and Philippine Sea plates subducting beneath the North America and the Eurasia plates. The subduction of the Philippine Sea plate causes mega-thrust earthquakes such as the 1923 Kanto earthquake (M 7.9) making 105,000 fatalities. A magnitude 7 or greater earthquake beneath this area is recently evaluated to occur with a probability of 70 % in 30 years. This is of immediate concern for the devastating loss of life and property because the Tokyo urban region now has a population of 42 million and is the center of approximately 40 % of the nation's activities, which may cause great global

  13. Earthquake Simulator Finds Tremor Triggers

    ScienceCinema

    Johnson, Paul

    2018-01-16

    Using a novel device that simulates earthquakes in a laboratory setting, a Los Alamos researcher has found that seismic waves-the sounds radiated from earthquakes-can induce earthquake aftershocks, often long after a quake has subsided. The research provides insight into how earthquakes may be triggered and how they recur. Los Alamos researcher Paul Johnson and colleague Chris Marone at Penn State have discovered how wave energy can be stored in certain types of granular materials-like the type found along certain fault lines across the globe-and how this stored energy can suddenly be released as an earthquake when hit by relatively small seismic waves far beyond the traditional “aftershock zone” of a main quake. Perhaps most surprising, researchers have found that the release of energy can occur minutes, hours, or even days after the sound waves pass; the cause of the delay remains a tantalizing mystery.

  14. Emergency medical rescue efforts after a major earthquake: lessons from the 2008 Wenchuan earthquake.

    PubMed

    Zhang, Lulu; Liu, Xu; Li, Youping; Liu, Yuan; Liu, Zhipeng; Lin, Juncong; Shen, Ji; Tang, Xuefeng; Zhang, Yi; Liang, Wannian

    2012-03-03

    Major earthquakes often result in incalculable environmental damage, loss of life, and threats to health. Tremendous progress has been made in response to many medical challenges resulting from earthquakes. However, emergency medical rescue is complicated, and great emphasis should be placed on its organisation to achieve the best results. The 2008 Wenchuan earthquake was one of the most devastating disasters in the past 10 years and caused more than 370,000 casualties. The lessons learnt from the medical disaster relief effort and the subsequent knowledge gained about the regulation and capabilities of medical and military back-up teams should be widely disseminated. In this Review we summarise and analyse the emergency medical rescue efforts after the Wenchuan earthquake. Establishment of a national disaster medical response system, an active and effective commanding system, successful coordination between rescue forces and government agencies, effective treatment, a moderate, timely and correct public health response, and long-term psychological support are all crucial to reduce mortality and morbidity and promote overall effectiveness of rescue efforts after a major earthquake. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Bayesian inference and interpretation of centroid moment tensors of the 2016 Kumamoto earthquake sequence, Kyushu, Japan

    NASA Astrophysics Data System (ADS)

    Hallo, Miroslav; Asano, Kimiyuki; Gallovič, František

    2017-09-01

    On April 16, 2016, Kumamoto prefecture in Kyushu region, Japan, was devastated by a shallow M JMA7.3 earthquake. The series of foreshocks started by M JMA6.5 foreshock 28 h before the mainshock. They have originated in Hinagu fault zone intersecting the mainshock Futagawa fault zone; hence, the tectonic background for this earthquake sequence is rather complex. Here we infer centroid moment tensors (CMTs) for 11 events with M JMA between 4.8 and 6.5, using strong motion records of the K-NET, KiK-net and F-net networks. We use upgraded Bayesian full-waveform inversion code ISOLA-ObsPy, which takes into account uncertainty of the velocity model. Such an approach allows us to reliably assess uncertainty of the CMT parameters including the centroid position. The solutions show significant systematic spatial and temporal variations throughout the sequence. Foreshocks are right-lateral steeply dipping strike-slip events connected to the NE-SW shear zone. Those located close to the intersection of the Hinagu and Futagawa fault zones are dipping slightly to ESE, while those in the southern area are dipping to WNW. Contrarily, aftershocks are mostly normal dip-slip events, being related to the N-S extensional tectonic regime. Most of the deviatoric moment tensors contain only minor CLVD component, which can be attributed to the velocity model uncertainty. Nevertheless, two of the CMTs involve a significant CLVD component, which may reflect complex rupture process. Decomposition of those moment tensors into two pure shear moment tensors suggests combined right-lateral strike-slip and normal dip-slip mechanisms, consistent with the tectonic settings of the intersection of the Hinagu and Futagawa fault zones.[Figure not available: see fulltext.

  16. Evacuation and Risk of Hypertension After the Great East Japan Earthquake: The Fukushima Health Management Survey.

    PubMed

    Ohira, Tetsuya; Hosoya, Mitsuaki; Yasumura, Seiji; Satoh, Hiroaki; Suzuki, Hitoshi; Sakai, Akira; Ohtsuru, Akira; Kawasaki, Yukihiko; Takahashi, Atsushi; Ozasa, Kotaro; Kobashi, Gen; Hashimoto, Shigeatsu; Kamiya, Kenji; Yamashita, Shunichi; Abe, Masafumi

    2016-09-01

    On March 11, 2011, the Great East Japan Earthquake occurred in Japan, with a nuclear accident subsequently occurring at the Fukushima Daiichi Nuclear Power Plant. The disaster forced many evacuees to change particular aspects of their lifestyles. This study assessed the hypothesis that evacuation may have increased the risk of hypertension among residents in Fukushima. A longitudinal study examined data collected from 31 252 Japanese participants aged 40 to 74 years sourced from general health checkups conducted in 13 communities between 2008 and 2010. Follow-up examinations were conducted from 2011 through 2013. A total of 21 989 participants (follow-up proportion, 70.4%) received follow-up examinations. Mean blood pressure significantly increased in both evacuees and nonevacuees after the disaster, with greater changes in blood pressure among the former. The changes in systolic and diastolic blood pressure among the evacuees and nonevacuees were +5.8/3.4 versus +4.6/2.1 mm Hg (P<0.01/P<0.0001) for men and +4.4/2.8 versus +4.1/1.7 mm Hg (P=0.33/P<0.0001) for women, respectively. Evacuation was associated with an increased risk of hypertension among men, and the age-adjusted hazard ratios of evacuation for incidence of hypertension were 1.24 (95% confidence interval, 1.11-1.39; P<0.001) for men and 1.05 (95% confidence interval, 0.94-1.17; P=0.37) for women, respectively. For men, after adjustment for confounding variables, the hazard ratio slightly decreased to 1.20, but the association was essentially unchanged. Blood pressure increased among residents, especially evacuees, in the evacuation zone of Fukushima prefecture after the Great East Japan Earthquake. Evacuation may be associated with an increased risk of hypertension among men in the 2 years after the disaster. © 2016 American Heart Association, Inc.

  17. Exploring Earthquakes in Real-Time

    NASA Astrophysics Data System (ADS)

    Bravo, T. K.; Kafka, A. L.; Coleman, B.; Taber, J. J.

    2013-12-01

    Earthquakes capture the attention of students and inspire them to explore the Earth. Adding the ability to view and explore recordings of significant and newsworthy earthquakes in real-time makes the subject even more compelling. To address this opportunity, the Incorporated Research Institutions for Seismology (IRIS), in collaboration with Moravian College, developed ';jAmaSeis', a cross-platform application that enables students to access real-time earthquake waveform data. Students can watch as the seismic waves are recorded on their computer, and can be among the first to analyze the data from an earthquake. jAmaSeis facilitates student centered investigations of seismological concepts using either a low-cost educational seismograph or streamed data from other educational seismographs or from any seismic station that sends data to the IRIS Data Management System. After an earthquake, students can analyze the seismograms to determine characteristics of earthquakes such as time of occurrence, distance from the epicenter to the station, magnitude, and location. The software has been designed to provide graphical clues to guide students in the analysis and assist in their interpretations. Since jAmaSeis can simultaneously record up to three stations from anywhere on the planet, there are numerous opportunities for student driven investigations. For example, students can explore differences in the seismograms from different distances from an earthquake and compare waveforms from different azimuthal directions. Students can simultaneously monitor seismicity at a tectonic plate boundary and in the middle of the plate regardless of their school location. This can help students discover for themselves the ideas underlying seismic wave propagation, regional earthquake hazards, magnitude-frequency relationships, and the details of plate tectonics. The real-time nature of the data keeps the investigations dynamic, and offers students countless opportunities to explore.

  18. Spatial Evaluation and Verification of Earthquake Simulators

    NASA Astrophysics Data System (ADS)

    Wilson, John Max; Yoder, Mark R.; Rundle, John B.; Turcotte, Donald L.; Schultz, Kasey W.

    2017-06-01

    In this paper, we address the problem of verifying earthquake simulators with observed data. Earthquake simulators are a class of computational simulations which attempt to mirror the topological complexity of fault systems on which earthquakes occur. In addition, the physics of friction and elastic interactions between fault elements are included in these simulations. Simulation parameters are adjusted so that natural earthquake sequences are matched in their scaling properties. Physically based earthquake simulators can generate many thousands of years of simulated seismicity, allowing for a robust capture of the statistical properties of large, damaging earthquakes that have long recurrence time scales. Verification of simulations against current observed earthquake seismicity is necessary, and following past simulator and forecast model verification methods, we approach the challenges in spatial forecast verification to simulators; namely, that simulator outputs are confined to the modeled faults, while observed earthquake epicenters often occur off of known faults. We present two methods for addressing this discrepancy: a simplistic approach whereby observed earthquakes are shifted to the nearest fault element and a smoothing method based on the power laws of the epidemic-type aftershock (ETAS) model, which distributes the seismicity of each simulated earthquake over the entire test region at a decaying rate with epicentral distance. To test these methods, a receiver operating characteristic plot was produced by comparing the rate maps to observed m>6.0 earthquakes in California since 1980. We found that the nearest-neighbor mapping produced poor forecasts, while the ETAS power-law method produced rate maps that agreed reasonably well with observations.

  19. Earthquakes March-April 1992

    USGS Publications Warehouse

    Person, Waverly J.

    1992-01-01

    The months of March and April were quite active seismically speaking. There was one major earthquake (7.0Earthquake-related deaths were reported in Iran, Costa Rica, Turkey, and Germany.

  20. Children's emotional experience two years after an earthquake: An exploration of knowledge of earthquakes and associated emotions

    PubMed Central

    Burro, Roberto; Hall, Rob

    2017-01-01

    A major earthquake has a potentially highly traumatic impact on children’s psychological functioning. However, while many studies on children describe negative consequences in terms of mental health and psychiatric disorders, little is known regarding how the developmental processes of emotions can be affected following exposure to disasters. Objectives We explored whether and how the exposure to a natural disaster such as the 2012 Emilia Romagna earthquake affected the development of children’s emotional competence in terms of understanding, regulating, and expressing emotions, after two years, when compared with a control group not exposed to the earthquake. We also examined the role of class level and gender. Method The sample included two groups of children (n = 127) attending primary school: The experimental group (n = 65) experienced the 2012 Emilia Romagna earthquake, while the control group (n = 62) did not. The data collection took place two years after the earthquake, when children were seven or ten-year-olds. Beyond assessing the children’s understanding of emotions and regulating abilities with standardized instruments, we employed semi-structured interviews to explore their knowledge of earthquakes and associated emotions, and a structured task on the intensity of some target emotions. Results We applied Generalized Linear Mixed Models. Exposure to the earthquake did not influence the understanding and regulation of emotions. The understanding of emotions varied according to class level and gender. Knowledge of earthquakes, emotional language, and emotions associated with earthquakes were, respectively, more complex, frequent, and intense for children who had experienced the earthquake, and at increasing ages. Conclusions Our data extend the generalizability of theoretical models on children’s psychological functioning following disasters, such as the dose-response model and the organizational-developmental model for child resilience, and

  1. The global distribution of magnitude 9 earthquakes

    NASA Astrophysics Data System (ADS)

    McCaffrey, R.

    2011-12-01

    The 2011 Tohoku M9 earthquake once again caught some in the earthquake community by surprise. The expectation of these massive quakes has been driven in the past by the over-reliance on our short, incomplete history of earthquakes and causal relationships derived from it. The logic applied is that if a great earthquake has not happened in the past, that we know of, one cannot happen in the future. Using the ~100-year global earthquake history, seismologists have promoted relationships between maximum earthquake sizes and other properties of subduction zones, leading to the notion that some subduction zones, like the Japan Trench, would never produce a magnitude ~9 event. The 2004 Andaman Mw = 9.2 earthquake, that occurred where there is slow subduction of old crust and a history of only moderate-sized earthquakes, seriously undermined such ideas. Given multi-century return times of the greatest earthquakes, ignorance of those return times and our very limited observation span, I suggest that we cannot yet make such determinations. Alternatively, using the length of a subduction zone that is available for slip as the predominant factor in determining maximum earthquake size, we cannot rule out that any subduction zone of a few hundred kilometers or more in length may be capable of producing a magnitude 9 or larger earthquake. Based on this method, the expected maximum size for the Japan Trench was 9.0 (McCaffrey, Geology, p. 263, 2008). The same approach portends a M > 9 for Java, with twice the population density as Honshu and much lower building standards. The Java Trench, and others where old crust subducts (Hikurangi, Marianas, Tonga, Kermadec), require increased awareness of the possibility for a great earthquake.

  2. Children's emotional experience two years after an earthquake: An exploration of knowledge of earthquakes and associated emotions.

    PubMed

    Raccanello, Daniela; Burro, Roberto; Hall, Rob

    2017-01-01

    We explored whether and how the exposure to a natural disaster such as the 2012 Emilia Romagna earthquake affected the development of children's emotional competence in terms of understanding, regulating, and expressing emotions, after two years, when compared with a control group not exposed to the earthquake. We also examined the role of class level and gender. The sample included two groups of children (n = 127) attending primary school: The experimental group (n = 65) experienced the 2012 Emilia Romagna earthquake, while the control group (n = 62) did not. The data collection took place two years after the earthquake, when children were seven or ten-year-olds. Beyond assessing the children's understanding of emotions and regulating abilities with standardized instruments, we employed semi-structured interviews to explore their knowledge of earthquakes and associated emotions, and a structured task on the intensity of some target emotions. We applied Generalized Linear Mixed Models. Exposure to the earthquake did not influence the understanding and regulation of emotions. The understanding of emotions varied according to class level and gender. Knowledge of earthquakes, emotional language, and emotions associated with earthquakes were, respectively, more complex, frequent, and intense for children who had experienced the earthquake, and at increasing ages. Our data extend the generalizability of theoretical models on children's psychological functioning following disasters, such as the dose-response model and the organizational-developmental model for child resilience, and provide further knowledge on children's emotional resources related to natural disasters, as a basis for planning educational prevention programs.

  3. 13 CFR 120.174 - Earthquake hazards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Earthquake hazards. 120.174... Applying to All Business Loans Requirements Imposed Under Other Laws and Orders § 120.174 Earthquake..., the construction must conform with the “National Earthquake Hazards Reduction Program (“NEHRP...

  4. 13 CFR 120.174 - Earthquake hazards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Earthquake hazards. 120.174... Applying to All Business Loans Requirements Imposed Under Other Laws and Orders § 120.174 Earthquake..., the construction must conform with the “National Earthquake Hazards Reduction Program (“NEHRP...

  5. 13 CFR 120.174 - Earthquake hazards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Earthquake hazards. 120.174... Applying to All Business Loans Requirements Imposed Under Other Laws and Orders § 120.174 Earthquake..., the construction must conform with the “National Earthquake Hazards Reduction Program (“NEHRP...

  6. 13 CFR 120.174 - Earthquake hazards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Earthquake hazards. 120.174... Applying to All Business Loans Requirements Imposed Under Other Laws and Orders § 120.174 Earthquake..., the construction must conform with the “National Earthquake Hazards Reduction Program (“NEHRP...

  7. Earthquake magnitude estimation using the τ c and P d method for earthquake early warning systems

    NASA Astrophysics Data System (ADS)

    Jin, Xing; Zhang, Hongcai; Li, Jun; Wei, Yongxiang; Ma, Qiang

    2013-10-01

    Earthquake early warning (EEW) systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire EEW system. In this paper, based on 142 earthquake events and 253 seismic records that were recorded by the KiK-net in Japan, and aftershocks of the large Wenchuan earthquake in Sichuan, we obtained earthquake magnitude estimation relationships using the τ c and P d methods. The standard variances of magnitude calculation of these two formulas are ±0.65 and ±0.56, respectively. The P d value can also be used to estimate the peak ground motion of velocity, then warning information can be released to the public rapidly, according to the estimation results. In order to insure the stability and reliability of magnitude estimation results, we propose a compatibility test according to the natures of these two parameters. The reliability of the early warning information is significantly improved though this test.

  8. Earthquakes at North Atlantic passive margins

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gregersen, S.; Basham, P.W.

    1989-01-01

    The main focus of this volume is the earthquakes that occur at and near the continental margins on both sides of the North Atlantic. The book, which contains the proceedings of the NATO workshop on Causes and Effects of Earthquakes at Passive Margins and in Areas of Postglacial Rebound on Both Sides of the North Atlantic, draws together the fields of geophysics, geology and geodesy to address the stress and strain in the Earth's crust. The resulting earthquakes produced on ancient geological fault zones and the associated seismic hazards these pose to man are also addressed. Postglacial rebound in Northmore » America and Fennoscandia is a minor source of earthquakes today, during the interglacial period, but evidence is presented to suggest that the ice sheets suppressed earthquake strain while they were in place, and released this strain as a pulse of significant earthquakes after the ice melted about 9000 years ago.« less

  9. Widespread Triggering of Earthquakes in the Central US by the 2011 M9.0 Tohoku-Oki Earthquake

    NASA Astrophysics Data System (ADS)

    Rubinstein, J. L.; Savage, H. M.

    2011-12-01

    The strong shaking of the 2011 M9.0 off-Tohoku earthquake triggered tectonic tremor and earthquakes in many locations around the world. We analyze broadband records from the USARRAY to identify triggered seismicity in more than 10 different locations in the Central United States. We identify triggered events in many states including: Kansas, Nebraska, Arkansas, Minnesota, and Iowa. The locally triggered earthquakes are obscured in broadband records by the Tohoku-Oki mainshock but can be revealed with high-pass filtering. With the exception of one location (central Arkansas), the triggered seismicity occurred in regions that are seismically quiet. The coincidence of this seismicity with the Tohoku-Oki event suggests that these earthquakes were triggered. The triggered seismicity in Arkansas occurred in a region where there has been an active swarm of seismicity since August 2010. There are two lines of evidence to indicate that the seismicity in Arkansas is triggered instead of part of the swarm: (1) we observe two earthquakes that initiate coincident with the arrival of shear wave and Love wave; (2) the seismicity rate increased dramatically following the Tohoku-Oki mainshock. Our observations of widespread earthquake triggering in regions thought to be seismically quiet remind us that earthquakes can occur in most any location. Studying additional teleseismic events has the potential to reveal regions with a propensity for earthquake triggering.

  10. Update earthquake risk assessment in Cairo, Egypt

    NASA Astrophysics Data System (ADS)

    Badawy, Ahmed; Korrat, Ibrahim; El-Hadidy, Mahmoud; Gaber, Hanan

    2017-07-01

    The Cairo earthquake (12 October 1992; m b = 5.8) is still and after 25 years one of the most painful events and is dug into the Egyptians memory. This is not due to the strength of the earthquake but due to the accompanied losses and damages (561 dead; 10,000 injured and 3000 families lost their homes). Nowadays, the most frequent and important question that should rise is "what if this earthquake is repeated today." In this study, we simulate the same size earthquake (12 October 1992) ground motion shaking and the consequent social-economic impacts in terms of losses and damages. Seismic hazard, earthquake catalogs, soil types, demographics, and building inventories were integrated into HAZUS-MH to produce a sound earthquake risk assessment for Cairo including economic and social losses. Generally, the earthquake risk assessment clearly indicates that "the losses and damages may be increased twice or three times" in Cairo compared to the 1992 earthquake. The earthquake risk profile reveals that five districts (Al-Sahel, El Basateen, Dar El-Salam, Gharb, and Madinat Nasr sharq) lie in high seismic risks, and three districts (Manshiyat Naser, El-Waily, and Wassat (center)) are in low seismic risk level. Moreover, the building damage estimations reflect that Gharb is the highest vulnerable district. The analysis shows that the Cairo urban area faces high risk. Deteriorating buildings and infrastructure make the city particularly vulnerable to earthquake risks. For instance, more than 90 % of the estimated buildings damages are concentrated within the most densely populated (El Basateen, Dar El-Salam, Gharb, and Madinat Nasr Gharb) districts. Moreover, about 75 % of casualties are in the same districts. Actually, an earthquake risk assessment for Cairo represents a crucial application of the HAZUS earthquake loss estimation model for risk management. Finally, for mitigation, risk reduction, and to improve the seismic performance of structures and assure life safety

  11. Revisiting the 1872 Owens Valley, California, Earthquake

    USGS Publications Warehouse

    Hough, S.E.; Hutton, K.

    2008-01-01

    The 26 March 1872 Owens Valley earthquake is among the largest historical earthquakes in California. The felt area and maximum fault displacements have long been regarded as comparable to, if not greater than, those of the great San Andreas fault earthquakes of 1857 and 1906, but mapped surface ruptures of the latter two events were 2-3 times longer than that inferred for the 1872 rupture. The preferred magnitude estimate of the Owens Valley earthquake has thus been 7.4, based largely on the geological evidence. Reinterpreting macroseismic accounts of the Owens Valley earthquake, we infer generally lower intensity values than those estimated in earlier studies. Nonetheless, as recognized in the early twentieth century, the effects of this earthquake were still generally more dramatic at regional distances than the macroseismic effects from the 1906 earthquake, with light damage to masonry buildings at (nearest-fault) distances as large as 400 km. Macroseismic observations thus suggest a magnitude greater than that of the 1906 San Francisco earthquake, which appears to be at odds with geological observations. However, while the mapped rupture length of the Owens Valley earthquake is relatively low, the average slip was high. The surface rupture was also complex and extended over multiple fault segments. It was first mapped in detail over a century after the earthquake occurred, and recent evidence suggests it might have been longer than earlier studies indicated. Our preferred magnitude estimate is Mw 7.8-7.9, values that we show are consistent with the geological observations. The results of our study suggest that either the Owens Valley earthquake was larger than the 1906 San Francisco earthquake or that, by virtue of source properties and/or propagation effects, it produced systematically higher ground motions at regional distances. The latter possibility implies that some large earthquakes in California will generate significantly larger ground motions than San

  12. The effects of earthquake measurement concepts and magnitude anchoring on individuals' perceptions of earthquake risk

    USGS Publications Warehouse

    Celsi, R.; Wolfinbarger, M.; Wald, D.

    2005-01-01

    The purpose of this research is to explore earthquake risk perceptions in California. Specifically, we examine the risk beliefs, feelings, and experiences of lay, professional, and expert individuals to explore how risk is perceived and how risk perceptions are formed relative to earthquakes. Our results indicate that individuals tend to perceptually underestimate the degree that earthquake (EQ) events may affect them. This occurs in large part because individuals' personal felt experience of EQ events are generally overestimated relative to experienced magnitudes. An important finding is that individuals engage in a process of "cognitive anchoring" of their felt EQ experience towards the reported earthquake magnitude size. The anchoring effect is moderated by the degree that individuals comprehend EQ magnitude measurement and EQ attenuation. Overall, the results of this research provide us with a deeper understanding of EQ risk perceptions, especially as they relate to individuals' understanding of EQ measurement and attenuation concepts. ?? 2005, Earthquake Engineering Research Institute.

  13. The Epidemic History of HIV-1 CRF07_BC in Hetian Prefecture and the Role of It on HIV Spreading in China.

    PubMed

    Wu, Jianjun; Guo, Hongxiong; Zhang, Jing; Liu, Xiaoming; Ayoupu, Aideaierli; Shen, Yuelan; Miao, Lifeng; Tang, Jihai; Lei, Yanhua; Su, Bin

    2017-04-01

    CRF07_BC is one of the most prevalent HIV-1 strains in China, and Xinjiang Uygur Autonomous Region has ever been considered to be a second epidemic center after Yunnan Province in previous studies. Here we use HIV-1 pol gene sequences identified from Hetian Prefecture located in Xinjiang Autonomous Region to reconstruct the epidemic history of HIV CRF07_BC strain circulating in this region. We found that CRF07_BC is the predominant HIV-1 form in Hetian Prefecture, and the estimated tMRCA analysis shows that there is no enough evidence supporting Xinjiang Autonomous Region as a second epidemic center of spreading HIV-1. It may imply that every city may be only a point among the HIV spreading network because of the frequent migration of population in the whole country nowadays.

  14. Earthquake triggering at alaskan volcanoes following the 3 November 2002 denali fault earthquake

    USGS Publications Warehouse

    Moran, S.C.; Power, J.A.; Stihler, S.D.; Sanchez, J.J.; Caplan-Auerbach, J.

    2004-01-01

    The 3 November 2002 Mw 7.9 Denali fault earthquake provided an excellent opportunity to investigate triggered earthquakes at Alaskan volcanoes. The Alaska Volcano Observatory operates short-period seismic networks on 24 historically active volcanoes in Alaska, 247-2159 km distant from the mainshock epicenter. We searched for evidence of triggered seismicity by examining the unfiltered waveforms for all stations in each volcano network for ???1 hr after the Mw 7.9 arrival time at each network and for significant increases in located earthquakes in the hours after the mainshock. We found compelling evidence for triggering only at the Katmai volcanic cluster (KVC, 720-755 km southwest of the epicenter), where small earthquakes with distinct P and 5 arrivals appeared within the mainshock coda at one station and a small increase in located earthquakes occurred for several hours after the mainshock. Peak dynamic stresses of ???0.1 MPa at Augustine Volcano (560 km southwest of the epicenter) are significantly lower than those recorded in Yellowstone and Utah (>3000 km southeast of the epicenter), suggesting that strong directivity effects were at least partly responsible for the lack of triggering at Alaskan volcanoes. We describe other incidents of earthquake-induced triggering in the KVC, and outline a qualitative magnitude/distance-dependent triggering threshold. We argue that triggering results from the perturbation of magmatic-hydrothermal systems in the KVC and suggest that the comparative lack of triggering at other Alaskan volcanoes could be a result of differences in the nature of magmatic-hydrothermal systems.

  15. Understanding Earthquake Hazard & Disaster in Himalaya - A Perspective on Earthquake Forecast in Himalayan Region of South Central Tibet

    NASA Astrophysics Data System (ADS)

    Shanker, D.; Paudyal, ,; Singh, H.

    2010-12-01

    It is not only the basic understanding of the phenomenon of earthquake, its resistance offered by the designed structure, but the understanding of the socio-economic factors, engineering properties of the indigenous materials, local skill and technology transfer models are also of vital importance. It is important that the engineering aspects of mitigation should be made a part of public policy documents. Earthquakes, therefore, are and were thought of as one of the worst enemies of mankind. Due to the very nature of release of energy, damage is evident which, however, will not culminate in a disaster unless it strikes a populated area. The word mitigation may be defined as the reduction in severity of something. The Earthquake disaster mitigation, therefore, implies that such measures may be taken which help reduce severity of damage caused by earthquake to life, property and environment. While “earthquake disaster mitigation” usually refers primarily to interventions to strengthen the built environment, and “earthquake protection” is now considered to include human, social and administrative aspects of reducing earthquake effects. It should, however, be noted that reduction of earthquake hazards through prediction is considered to be the one of the effective measures, and much effort is spent on prediction strategies. While earthquake prediction does not guarantee safety and even if predicted correctly the damage to life and property on such a large scale warrants the use of other aspects of mitigation. While earthquake prediction may be of some help, mitigation remains the main focus of attention of the civil society. Present study suggests that anomalous seismic activity/ earthquake swarm existed prior to the medium size earthquakes in the Nepal Himalaya. The mainshocks were preceded by the quiescence period which is an indication for the occurrence of future seismic activity. In all the cases, the identified episodes of anomalous seismic activity were

  16. Thermal Infrared Anomalies of Several Strong Earthquakes

    PubMed Central

    Wei, Congxin; Guo, Xiao; Qin, Manzhong

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of “time-frequency relative power spectrum.” (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting. PMID:24222728

  17. Thermal infrared anomalies of several strong earthquakes.

    PubMed

    Wei, Congxin; Zhang, Yuansheng; Guo, Xiao; Hui, Shaoxing; Qin, Manzhong; Zhang, Ying

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of "time-frequency relative power spectrum." (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

  18. Pre-Earthquake Unipolar Electromagnetic Pulses

    NASA Astrophysics Data System (ADS)

    Scoville, J.; Freund, F.

    2013-12-01

    Transient ultralow frequency (ULF) electromagnetic (EM) emissions have been reported to occur before earthquakes [1,2]. They suggest powerful transient electric currents flowing deep in the crust [3,4]. Prior to the M=5.4 Alum Rock earthquake of Oct. 21, 2007 in California a QuakeFinder triaxial search-coil magnetometer located about 2 km from the epicenter recorded unusual unipolar pulses with the approximate shape of a half-cycle of a sine wave, reaching amplitudes up to 30 nT. The number of these unipolar pulses increased as the day of the earthquake approached. These pulses clearly originated around the hypocenter. The same pulses have since been recorded prior to several medium to moderate earthquakes in Peru, where they have been used to triangulate the location of the impending earthquakes [5]. To understand the mechanism of the unipolar pulses, we first have to address the question how single current pulses can be generated deep in the Earth's crust. Key to this question appears to be the break-up of peroxy defects in the rocks in the hypocenter as a result of the increase in tectonic stresses prior to an earthquake. We investigate the mechanism of the unipolar pulses by coupling the drift-diffusion model of semiconductor theory to Maxwell's equations, thereby producing a model describing the rock volume that generates the pulses in terms of electromagnetism and semiconductor physics. The system of equations is then solved numerically to explore the electromagnetic radiation associated with drift-diffusion currents of electron-hole pairs. [1] Sharma, A. K., P. A. V., and R. N. Haridas (2011), Investigation of ULF magnetic anomaly before moderate earthquakes, Exploration Geophysics 43, 36-46. [2] Hayakawa, M., Y. Hobara, K. Ohta, and K. Hattori (2011), The ultra-low-frequency magnetic disturbances associated with earthquakes, Earthquake Science, 24, 523-534. [3] Bortnik, J., T. E. Bleier, C. Dunson, and F. Freund (2010), Estimating the seismotelluric current

  19. Earthquake Warning Performance in Vallejo for the South Napa Earthquake

    NASA Astrophysics Data System (ADS)

    Wurman, G.; Price, M.

    2014-12-01

    In 2002 and 2003, Seismic Warning Systems, Inc. installed first-generation QuakeGuardTM earthquake warning devices at all eight fire stations in Vallejo, CA. These devices are designed to detect the P-wave of an earthquake and initiate predetermined protective actions if the impending shaking is estimated at approximately Modifed Mercalli Intensity V or greater. At the Vallejo fire stations the devices were set up to sound an audio alert over the public address system and to command the equipment bay doors to open. In August 2014, after more than 11 years of operating in the fire stations with no false alarms, the five units that were still in use triggered correctly on the MW 6.0 South Napa earthquake, less than 16 km away. The audio alert sounded in all five stations, providing fire fighters with 1.5 to 2.5 seconds of warning before the arrival of the S-wave, and the equipment bay doors opened in three of the stations. In one station the doors were disconnected from the QuakeGuard device, and another station lost power before the doors opened completely. These problems highlight just a small portion of the complexity associated with realizing actionable earthquake warnings. The issues experienced in this earthquake have already been addressed in subsequent QuakeGuard product generations, with downstream connection monitoring and backup power for critical systems. The fact that the fire fighters in Vallejo were afforded even two seconds of warning at these epicentral distances results from the design of the QuakeGuard devices, which focuses on rapid false positive rejection and ground motion estimates. We discuss the performance of the ground motion estimation algorithms, with an emphasis on the accuracy and timeliness of the estimates at close epicentral distances.

  20. Earthquake Shaking - Finding the "Hot Spots"

    USGS Publications Warehouse

    Field, Edward; Jones, Lucile; Jordan, Tom; Benthien, Mark; Wald, Lisa

    2001-01-01

    A new Southern California Earthquake Center study has quantified how local geologic conditions affect the shaking experienced in an earthquake. The important geologic factors at a site are softness of the rock or soil near the surface and thickness of the sediments above hard bedrock. Even when these 'site effects' are taken into account, however, each earthquake exhibits unique 'hotspots' of anomalously strong shaking. Better predictions of strong ground shaking will therefore require additional geologic data and more comprehensive computer simulations of individual earthquakes.

  1. Earth's rotation variations and earthquakes 2010-2011

    NASA Astrophysics Data System (ADS)

    Ostřihanský, L.

    2012-01-01

    In contrast to unsuccessful searching (lasting over 150 years) for correlation of earthquakes with biweekly tides, the author found correlation of earthquakes with sidereal 13.66 days Earth's rotation variations expressed as length of a day (LOD) measured daily by International Earth's Rotation Service. After short mention about earthquakes M 8.8 Denali Fault Alaska 3 November 2002 triggered on LOD maximum and M 9.1 Great Sumatra earthquake 26 December 2004 triggered on LOD minimum and the full Moon, the main object of this paper are earthquakes of period 2010-June 2011: M 7.0 Haiti (12 January 2010 on LOD minimum, M 8.8 Maule Chile 12 February 2010 on LOD maximum, map constructed on the Indian plate revealing 6 earthquakes from 7 on LOD minimum in Sumatra and Andaman Sea region, M 7.1 New Zealand Christchurch 9 September 2010 on LOD minimum and M 6.3 Christchurch 21 February 2011 on LOD maximum, and M 9.1 Japan near coast of Honshu 11 March 2011 on LOD minimum. It was found that LOD minimums coincide with full or new Moon only twice in a year in solstices. To prove that determined coincidences of earthquakes and LOD extremes stated above are not accidental events, histograms were constructed of earthquake occurrences and their position on LOD graph deeply in the past, in some cases from the time the IERS (International Earth's Rotation Service) started to measure the Earth's rotation variations in 1962. Evaluations of histograms and the Schuster's test have proven that majority of earthquakes are triggered in both Earth's rotation deceleration and acceleration. Because during these coincidences evident movements of lithosphere occur, among others measured by GPS, it is concluded that Earth's rotation variations effectively contribute to the lithospheric plates movement. Retrospective overview of past earthquakes revealed that the Great Sumatra earthquake 26 December 2004 had its equivalent in the shape of LOD graph, full Moon position, and character of aftershocks

  2. Pre-earthquake magnetic pulses

    NASA Astrophysics Data System (ADS)

    Scoville, J.; Heraud, J.; Freund, F.

    2015-08-01

    A semiconductor model of rocks is shown to describe unipolar magnetic pulses, a phenomenon that has been observed prior to earthquakes. These pulses are suspected to be generated deep in the Earth's crust, in and around the hypocentral volume, days or even weeks before earthquakes. Their extremely long wavelength allows them to pass through kilometers of rock. Interestingly, when the sources of these pulses are triangulated, the locations coincide with the epicenters of future earthquakes. We couple a drift-diffusion semiconductor model to a magnetic field in order to describe the electromagnetic effects associated with electrical currents flowing within rocks. The resulting system of equations is solved numerically and it is seen that a volume of rock may act as a diode that produces transient currents when it switches bias. These unidirectional currents are expected to produce transient unipolar magnetic pulses similar in form, amplitude, and duration to those observed before earthquakes, and this suggests that the pulses could be the result of geophysical semiconductor processes.

  3. Automatic Earthquake Detection by Active Learning

    NASA Astrophysics Data System (ADS)

    Bergen, K.; Beroza, G. C.

    2017-12-01

    In recent years, advances in machine learning have transformed fields such as image recognition, natural language processing and recommender systems. Many of these performance gains have relied on the availability of large, labeled data sets to train high-accuracy models; labeled data sets are those for which each sample includes a target class label, such as waveforms tagged as either earthquakes or noise. Earthquake seismologists are increasingly leveraging machine learning and data mining techniques to detect and analyze weak earthquake signals in large seismic data sets. One of the challenges in applying machine learning to seismic data sets is the limited labeled data problem; learning algorithms need to be given examples of earthquake waveforms, but the number of known events, taken from earthquake catalogs, may be insufficient to build an accurate detector. Furthermore, earthquake catalogs are known to be incomplete, resulting in training data that may be biased towards larger events and contain inaccurate labels. This challenge is compounded by the class imbalance problem; the events of interest, earthquakes, are infrequent relative to noise in continuous data sets, and many learning algorithms perform poorly on rare classes. In this work, we investigate the use of active learning for automatic earthquake detection. Active learning is a type of semi-supervised machine learning that uses a human-in-the-loop approach to strategically supplement a small initial training set. The learning algorithm incorporates domain expertise through interaction between a human expert and the algorithm, with the algorithm actively posing queries to the user to improve detection performance. We demonstrate the potential of active machine learning to improve earthquake detection performance with limited available training data.

  4. Urban Earthquakes - Reducing Building Collapse Through Education

    NASA Astrophysics Data System (ADS)

    Bilham, R.

    2004-12-01

    Fatalities from earthquakes rose from 6000k to 9000k/year in the past decade, yet the ratio of numbers of earthquake fatalities to instantaneous population continues to fall. Since 1950 the ratio declined worldwide by a factor of three, but in some countries the ratio has changed little. E.g in Iran, 1 in 3000 people can expect to die in an earthquake, a percentage that has not changed significantly since 1890. Fatalities from earthquakes remain high in those countries that have traditionally suffered from frequent large earthquakes (Turkey, Iran, Japan, and China), suggesting that the exposure time of recently increased urban populations in other countries may be too short to have interacted with earthquakes with long recurrence intervals. This in turn, suggests that disasters of unprecendented size will occur (more than 1 million fatalities) when future large earthquakes occur close to megacities. However, population growth is most rapid in cities of less than 1 million people in the developing nations, where the financial ability to implement earthquake resistant construction methods is limited. In that structural collapse can often be traced to ignorance about the forces at work in an earthquake, the future collapse of buildings presently under construction could be much reduced were contractors, builders and occupants educated in the principles of earthquake resistant assembly. Education of builders who are tempted to cut assembly costs is likely to be more cost effective than material aid.

  5. Earthquake effects at nuclear reactor facilities: San Fernando earthquake of February 9th, 1971

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Howard, G.; Ibanez, P.; Matthiesen, F.

    1972-02-01

    The effects of the San Fernando earthquake of February 9, 1971 on 26 reactor facilities located in California, Arizona, and Nevada are reported. The safety performance of the facilities during the earthquake is discussed. (JWR)

  6. On near-source earthquake triggering

    USGS Publications Warehouse

    Parsons, T.; Velasco, A.A.

    2009-01-01

    When one earthquake triggers others nearby, what connects them? Two processes are observed: static stress change from fault offset and dynamic stress changes from passing seismic waves. In the near-source region (r ??? 50 km for M ??? 5 sources) both processes may be operating, and since both mechanisms are expected to raise earthquake rates, it is difficult to isolate them. We thus compare explosions with earthquakes because only earthquakes cause significant static stress changes. We find that large explosions at the Nevada Test Site do not trigger earthquakes at rates comparable to similar magnitude earthquakes. Surface waves are associated with regional and long-range dynamic triggering, but we note that surface waves with low enough frequency to penetrate to depths where most aftershocks of the 1992 M = 5.7 Little Skull Mountain main shock occurred (???12 km) would not have developed significant amplitude within a 50-km radius. We therefore focus on the best candidate phases to cause local dynamic triggering, direct waves that pass through observed near-source aftershock clusters. We examine these phases, which arrived at the nearest (200-270 km) broadband station before the surface wave train and could thus be isolated for study. Direct comparison of spectral amplitudes of presurface wave arrivals shows that M ??? 5 explosions and earthquakes deliver the same peak dynamic stresses into the near-source crust. We conclude that a static stress change model can readily explain observed aftershock patterns, whereas it is difficult to attribute near-source triggering to a dynamic process because of the dearth of aftershocks near large explosions.

  7. Tsunami damage in the southern Kanto region from the 1703 Genroku Kanto earthquake

    NASA Astrophysics Data System (ADS)

    Muragishi, J.; Satake, K.

    2014-12-01

    The Genroku Kanto earthquake occurred on Dec. 31th, 1703 along the Sagami Trough where the Philippine Sea plate subducts beneath the continental plate. Hatori (1976) reported significant tsunami damage with estimated tsunami heights of 5 m along Kujukuri coast on the Pacific Ocean, and estimated the tsunami heights in the inner Tokyo Bay as approximately 2 m. In Tokyo Bay, there are no records that indicate the tsunami inundated residential areas, while some descriptions of tsunami are recorded in Edo, the former Tokyo. The notice from Edo City Commissioners to residences in Edo described that the tsunami came up to the upper-limit of Sumida River in Tokyo, where four major arrivals of tsunamis were reported. According to Saihen-onkoroku, tsunami came to Fukagawa, where one person was killed by throwing away from a boat affected by the tsunami. In Ichikawa along the coast of Chiba Prefecture in Tokyo Bay, there are historical records about the salt farm. The embankments were collapsed and the salt farm was ruined, while the tsunami damage is not described. At this location, the damage due to storm surge in 1680 is recorded in the same document. Although storm surge damage is recorded in detail, there are no records about the Genroku tsunami, suggesting that the tsunami damage, if any, is slighter than the storm surge. Along the Kujukui coast outside the Tokyo bay, the descriptions are not only damage to buildings or deaths but also an influx of sand brought by the tsunami which damaged the agricultural land. In summary, it became certain that the Genroku tsunami caused some damage in the inner Tokyo Bay area. In addition, we found that a wide range of farmland was suffered by influx of sand and crops could not grow well. Such a description may be able to contribute to the tsunami deposits in future research. This study was supported by the Special Project for Reducing Vulnerability for Urban Mega Earthquake Disasters from the MEXT of Japan.

  8. Remotely triggered earthquakes following moderate main shocks

    USGS Publications Warehouse

    Hough, S.E.

    2007-01-01

    Since 1992, remotely triggered earthquakes have been identified following large (M > 7) earthquakes in California as well as in other regions. These events, which occur at much greater distances than classic aftershocks, occur predominantly in active geothermal or volcanic regions, leading to theories that the earthquakes are triggered when passing seismic waves cause disruptions in magmatic or other fluid systems. In this paper, I focus on observations of remotely triggered earthquakes following moderate main shocks in diverse tectonic settings. I summarize evidence that remotely triggered earthquakes occur commonly in mid-continent and collisional zones. This evidence is derived from analysis of both historic earthquake sequences and from instrumentally recorded M5-6 earthquakes in eastern Canada. The latter analysis suggests that, while remotely triggered earthquakes do not occur pervasively following moderate earthquakes in eastern North America, a low level of triggering often does occur at distances beyond conventional aftershock zones. The inferred triggered events occur at the distances at which SmS waves are known to significantly increase ground motions. A similar result was found for 28 recent M5.3-7.1 earthquakes in California. In California, seismicity is found to increase on average to a distance of at least 200 km following moderate main shocks. This supports the conclusion that, even at distances of ???100 km, dynamic stress changes control the occurrence of triggered events. There are two explanations that can account for the occurrence of remotely triggered earthquakes in intraplate settings: (1) they occur at local zones of weakness, or (2) they occur in zones of local stress concentration. ?? 2007 The Geological Society of America.

  9. Tsunami inundation after the Great East Japan Earthquake and mortality of affected communities.

    PubMed

    Ishiguro, A; Yano, E

    2015-10-01

    To examine the relationship between mortality rate and tsunami inundation after the Great East Japan Earthquake (GEJE) in 2011. Cross-sectional study. One hundred and fifty-five town or village sections in Ishinomaki, Myagi Prefecture, were included in this study. Three areas in the city were classified by characteristic landforms: plains area (n = 114), ria coastal area (n = 27) and Kitakami riverside (n = 14). The correlation coefficient between tsunami inundation depth and mortality rate was calculated for each area, and the differences between the areas were examined. Furthermore, multivariate analyses adjusted for the characteristics of the sections were conducted using census data taken before the GEJE. An association was found between inundation depth and mortality rate for Ishinomaki as a whole (r = 0.65, P < 0.001), Kitakami riverside (r = 0.85, P < 0.001) and the plains area (r = 0.75, P < 0.001) in separate analyses. However, no association was detected between inundation depth and mortality rate for the ria coastal area (r = 0.14, P = 0.47). The ria coastal area has good accessibility to the hills and tight bonding between members of the community. These factors seemed to play crucial roles in the lower mortality rate in this area despite the deep inundation. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Forearc deformation and great subduction earthquakes: implications for cascadia offshore earthquake potential.

    PubMed

    McCaffrey, R; Goldfinger, C

    1995-02-10

    The maximum size of thrust earthquakes at the world's subduction zones appears to be limited by anelastic deformation of the overriding plate. Anelastic strain in weak forearcs and roughness of the plate interface produced by faults cutting the forearc may limit the size of thrust earthquakes by inhibiting the buildup of elastic strain energy or slip propagation or both. Recently discovered active strike-slip faults in the submarine forearc of the Cascadia subduction zone show that the upper plate there deforms rapidly in response to arc-parallel shear. Thus, Cascadia, as a result of its weak, deforming upper plate, may be the type of subduction zone at which great (moment magnitude approximately 9) thrust earthquakes do not occur.

  11. Analysis of HIV prevalence among pregnant women in Liangshan Prefecture, China, from 2009 to 2015.

    PubMed

    Yang, Shujuan; Yang, Chao; Liao, Qiang; Zhai, Wenwen; Yu, Gang; Xiao, Lin; Wang, Qixing; Gong, Yuhan; Zhang, Suhua; Yao, Yongna; Wang, Ke; Wang, Ju; Bian, Shaochao; Liu, Qian

    2017-01-01

    Yi people make up about 50% of the population in Liangshan Prefecture, Sichuan Province, China, but accounted for 88.07% of new HIV cases in the prefecture from 2011 to 2013. This study evaluated HIV prevalence in pregnant women of Liangshan Prefecture using HIV sentinel surveillance (HSS) data over the period of 2009 to 2015. Xichang, Zhaojue County, and Butuo County were selected as HSS sites. We investigated the temporal trends in HIV prevalence in these areas, and the association between demographic and behavioral characteristics and risk of HIV infection. Data on a total of 2797 pregnant women in Xichang and 3983 pregnant women in Zhaojue and Butuo was collected for the period 2009 to 2015. There was a fluctuating HIV prevalence among pregnant women of Xichang, with a rate of 0.75% in 2015 (χ2trend = 2.27, P = 0.13). HIV prevalence among pregnant women of Zhaojue and Butuo was consistently high, varying between 3.4% (9/267, 2011) and 10.3% (82/796, 2012) over the period of 2010 to 2015 (χ2trend = 0.12, P = 0.73). In Xichang, we found that Yi ethnicity (OR = 11.37, 95% CI = 2.92-44.25) and a husband who used drugs (OR = 32.13, 95% CI = 5.33-193.67) were significantly associated with HIV risk in pregnant women. For Zhaojue and Butuo, we observed that pregnant women had a higher risk of HIV infection when they were over 30 years old (OR = 1.72, 95% CI = 1.17-2.52), when they had a higher number of previous births, when their husbands had a history of migrating for work (OR = 1.56, 95% CI = 1.16-2.08), and when they had a history of other sexually transmitted infections (OR = 2.19, 95% CI = 1.16-2.08). Compared to those with a primary school education or below, pregnant women with a secondary or high school education level had a lower risk of HIV infection (OR = 0.28, 95% CI = 0.09-0.89). Our results indicate that there is a serious HIV epidemic among pregnant Yi women, especially for those with less education, more past births, or a husband with a history of

  12. Frog Swarms: Earthquake Precursors or False Alarms?

    PubMed Central

    Grant, Rachel A.; Conlan, Hilary

    2013-01-01

    Simple Summary Media reports linking unusual animal behaviour with earthquakes can potentially create false alarms and unnecessary anxiety among people that live in earthquake risk zones. Recently large frog swarms in China and elsewhere have been reported as earthquake precursors in the media. By examining international media reports of frog swarms since 1850 in comparison to earthquake data, it was concluded that frog swarms are naturally occurring dispersal behaviour of juveniles and are not associated with earthquakes. However, the media in seismic risk areas may be more likely to report frog swarms, and more likely to disseminate reports on frog swarms after earthquakes have occurred, leading to an apparent link between frog swarms and earthquakes. Abstract In short-term earthquake risk forecasting, the avoidance of false alarms is of utmost importance to preclude the possibility of unnecessary panic among populations in seismic hazard areas. Unusual animal behaviour prior to earthquakes has been reported for millennia but has rarely been scientifically documented. Recently large migrations or unusual behaviour of amphibians have been linked to large earthquakes, and media reports of large frog and toad migrations in areas of high seismic risk such as Greece and China have led to fears of a subsequent large earthquake. However, at certain times of year large migrations are part of the normal behavioural repertoire of amphibians. News reports of “frog swarms” from 1850 to the present day were examined for evidence that this behaviour is a precursor to large earthquakes. It was found that only two of 28 reported frog swarms preceded large earthquakes (Sichuan province, China in 2008 and 2010). All of the reported mass migrations of amphibians occurred in late spring, summer and autumn and appeared to relate to small juvenile anurans (frogs and toads). It was concluded that most reported “frog swarms” are actually normal behaviour, probably caused by

  13. Incubation of Chile's 1960 Earthquake

    NASA Astrophysics Data System (ADS)

    Atwater, B. F.; Cisternas, M.; Salgado, I.; Machuca, G.; Lagos, M.; Eipert, A.; Shishikura, M.

    2003-12-01

    Infrequent occurrence of giant events may help explain how the 1960 Chile earthquake attained M 9.5. Although old documents imply that this earthquake followed great earthquakes of 1575, 1737 and 1837, only three earthquakes of the past 1000 years produced geologic records like those for 1960. These earlier earthquakes include the 1575 event but not 1737 or 1837. Because the 1960 earthquake had nearly twice the seismic slip expected from plate convergence since 1837, much of the strain released in 1960 may have been accumulating since 1575. Geologic evidence for such incubation comes from new paleoseismic findings at the R¡o Maullin estuary, which indents the Pacific coast at 41.5§ S midway along the 1960 rupture. The 1960 earthquake lowered the area by 1.5 m, and the ensuing tsunami spread sand across lowland soils. The subsidence killed forests and changed pastures into sandy tidal flats. Guided by these 1960 analogs, we inferred tsunami and earthquake history from sand sheets, tree rings, and old maps. At Chuyaquen, 10 km upriver from the sea, we studied sand sheets in 31 backhoe pits on a geologic transect 1 km long. Each sheet overlies the buried soil of a former marsh or meadow. The sand sheet from 1960 extends the entire length of the transect. Three earlier sheets can be correlated at least half that far. The oldest one, probably a tsunami deposit, surrounds herbaceous plants that date to AD 990-1160. Next comes a sandy tidal-flat deposit dated by stratigraphic position to about 1000-1500. The penultimate sheet is a tsunami deposit younger than twigs from 1410-1630. It probably represents the 1575 earthquake, whose accounts of shaking, tsunami, and landslides rival those of 1960. In that case, the record excludes the 1737 and 1837 events. The 1737 and 1837 events also appear missing in tree-ring evidence from islands of Misquihue, 30 km upriver from the sea. Here the subsidence in 1960 admitted brackish tidal water that defoliated tens of thousands of

  14. Bayesian exploration of recent Chilean earthquakes

    NASA Astrophysics Data System (ADS)

    Duputel, Zacharie; Jiang, Junle; Jolivet, Romain; Simons, Mark; Rivera, Luis; Ampuero, Jean-Paul; Liang, Cunren; Agram, Piyush; Owen, Susan; Ortega, Francisco; Minson, Sarah

    2016-04-01

    The South-American subduction zone is an exceptional natural laboratory for investigating the behavior of large faults over the earthquake cycle. It is also a playground to develop novel modeling techniques combining different datasets. Coastal Chile was impacted by two major earthquakes in the last two years: the 2015 M 8.3 Illapel earthquake in central Chile and the 2014 M 8.1 Iquique earthquake that ruptured the central portion of the 1877 seismic gap in northern Chile. To gain better understanding of the distribution of co-seismic slip for those two earthquakes, we derive joint kinematic finite fault models using a combination of static GPS offsets, radar interferograms, tsunami measurements, high-rate GPS waveforms and strong motion data. Our modeling approach follows a Bayesian formulation devoid of a priori smoothing thereby allowing us to maximize spatial resolution of the inferred family of models. The adopted approach also attempts to account for major sources of uncertainty in the Green's functions. The results reveal different rupture behaviors for the 2014 Iquique and 2015 Illapel earthquakes. The 2014 Iquique earthquake involved a sharp slip zone and did not rupture to the trench. The 2015 Illapel earthquake nucleated close to the coast and propagated toward the trench with significant slip apparently reaching the trench or at least very close to the trench. At the inherent resolution of our models, we also present the relationship of co-seismic models to the spatial distribution of foreshocks, aftershocks and fault coupling models.

  15. Scoring annual earthquake predictions in China

    NASA Astrophysics Data System (ADS)

    Zhuang, Jiancang; Jiang, Changsheng

    2012-02-01

    The Annual Consultation Meeting on Earthquake Tendency in China is held by the China Earthquake Administration (CEA) in order to provide one-year earthquake predictions over most China. In these predictions, regions of concern are denoted together with the corresponding magnitude range of the largest earthquake expected during the next year. Evaluating the performance of these earthquake predictions is rather difficult, especially for regions that are of no concern, because they are made on arbitrary regions with flexible magnitude ranges. In the present study, the gambling score is used to evaluate the performance of these earthquake predictions. Based on a reference model, this scoring method rewards successful predictions and penalizes failures according to the risk (probability of being failure) that the predictors have taken. Using the Poisson model, which is spatially inhomogeneous and temporally stationary, with the Gutenberg-Richter law for earthquake magnitudes as the reference model, we evaluate the CEA predictions based on 1) a partial score for evaluating whether issuing the alarmed regions is based on information that differs from the reference model (knowledge of average seismicity level) and 2) a complete score that evaluates whether the overall performance of the prediction is better than the reference model. The predictions made by the Annual Consultation Meetings on Earthquake Tendency from 1990 to 2003 are found to include significant precursory information, but the overall performance is close to that of the reference model.

  16. Potential for a large earthquake near Los Angeles inferred from the 2014 La Habra earthquake.

    PubMed

    Donnellan, Andrea; Grant Ludwig, Lisa; Parker, Jay W; Rundle, John B; Wang, Jun; Pierce, Marlon; Blewitt, Geoffrey; Hensley, Scott

    2015-09-01

    Tectonic motion across the Los Angeles region is distributed across an intricate network of strike-slip and thrust faults that will be released in destructive earthquakes similar to or larger than the 1933  M 6.4 Long Beach and 1994  M 6.7 Northridge events. Here we show that Los Angeles regional thrust, strike-slip, and oblique faults are connected and move concurrently with measurable surface deformation, even in moderate magnitude earthquakes, as part of a fault system that accommodates north-south shortening and westerly tectonic escape of northern Los Angeles. The 28 March 2014 M 5.1 La Habra earthquake occurred on a northeast striking, northwest dipping left-lateral oblique thrust fault northeast of Los Angeles. We present crustal deformation observation spanning the earthquake showing that concurrent deformation occurred on several structures in the shallow crust. The seismic moment of the earthquake is 82% of the total geodetic moment released. Slip within the unconsolidated upper sedimentary layer may reflect shallow release of accumulated strain on still-locked deeper structures. A future M 6.1-6.3 earthquake would account for the accumulated strain. Such an event could occur on any one or several of these faults, which may not have been identified by geologic surface mapping.

  17. Potential for a large earthquake near Los Angeles inferred from the 2014 La Habra earthquake

    PubMed Central

    Grant Ludwig, Lisa; Parker, Jay W.; Rundle, John B.; Wang, Jun; Pierce, Marlon; Blewitt, Geoffrey; Hensley, Scott

    2015-01-01

    Abstract Tectonic motion across the Los Angeles region is distributed across an intricate network of strike‐slip and thrust faults that will be released in destructive earthquakes similar to or larger than the 1933 M6.4 Long Beach and 1994 M6.7 Northridge events. Here we show that Los Angeles regional thrust, strike‐slip, and oblique faults are connected and move concurrently with measurable surface deformation, even in moderate magnitude earthquakes, as part of a fault system that accommodates north‐south shortening and westerly tectonic escape of northern Los Angeles. The 28 March 2014 M5.1 La Habra earthquake occurred on a northeast striking, northwest dipping left‐lateral oblique thrust fault northeast of Los Angeles. We present crustal deformation observation spanning the earthquake showing that concurrent deformation occurred on several structures in the shallow crust. The seismic moment of the earthquake is 82% of the total geodetic moment released. Slip within the unconsolidated upper sedimentary layer may reflect shallow release of accumulated strain on still‐locked deeper structures. A future M6.1–6.3 earthquake would account for the accumulated strain. Such an event could occur on any one or several of these faults, which may not have been identified by geologic surface mapping. PMID:27981074

  18. Incidence of pests and viral disease on pepino (Solanum muricatum Ait.) in Kanagawa Prefecture, Japan.

    PubMed

    Kim, Ok-Kyung; Ishikawa, Tadashi; Yamada, Yoshihiro; Sato, Takuma; Shinohara, Hirosuke; Takahata, Ken

    2017-01-01

    The solanaceous fruit crop pepino ( Solanum muricatum Ait.), originating in the Andes, is grown commercially in South American countries and New Zealand. In these areas, pests and diseases of pepino have been identified well; however, to date, these have seldom been investigated in detail in Japan. Herein, we attempt to reconstruct an agricultural production system for commercial pepino crops in Japan, and evaluate the incidence of pests and viral diseases on pepino. The findings of this study will facilitate in developing a better crop system for the commercial cultivation of healthy pepino fruits. A total of 11 species, comprising nine insects and two mites, were recognized as pests of pepino plants in our experimental fields in Kanagawa Prefecture, central Honshu, Japan. Of these pest species, the two-spotted spider mite Tetranychus urticae Koch, 1836 and the cotton aphid Aphis gossypii Glover, 1877, were remarkably abundant than the other pest species. Eventually, 13 species, including two previously recorded, are currently recognized as the pests of pepino in Japan. With regard to viruses, we tested two species Alfalfa mosaic virus (AMV) and Cucumber mosaic virus (CMV), as well as three genera Carlavirus , Potexvirus , and Potyvirus . No virus was detected in symptomatic pepino leaves collected in our experimental fields. This is a first report on the identification of pests on pepino plants in Kanagawa Prefecture, Japan and elucidates the relationship between currently occurring pests of pepino plants and potential viral pathogens that they can transmit.

  19. Prompt Assessment of Global Earthquakes for Response (PAGER): A System for Rapidly Determining the Impact of Earthquakes Worldwide

    USGS Publications Warehouse

    Earle, Paul S.; Wald, David J.; Jaiswal, Kishor S.; Allen, Trevor I.; Hearne, Michael G.; Marano, Kristin D.; Hotovec, Alicia J.; Fee, Jeremy

    2009-01-01

    Within minutes of a significant earthquake anywhere on the globe, the U.S. Geological Survey (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER) system assesses its potential societal impact. PAGER automatically estimates the number of people exposed to severe ground shaking and the shaking intensity at affected cities. Accompanying maps of the epicentral region show the population distribution and estimated ground-shaking intensity. A regionally specific comment describes the inferred vulnerability of the regional building inventory and, when available, lists recent nearby earthquakes and their effects. PAGER's results are posted on the USGS Earthquake Program Web site (http://earthquake.usgs.gov/), consolidated in a concise one-page report, and sent in near real-time to emergency responders, government agencies, and the media. Both rapid and accurate results are obtained through manual and automatic updates of PAGER's content in the hours following significant earthquakes. These updates incorporate the most recent estimates of earthquake location, magnitude, faulting geometry, and first-hand accounts of shaking. PAGER relies on a rich set of earthquake analysis and assessment tools operated by the USGS and contributing Advanced National Seismic System (ANSS) regional networks. A focused research effort is underway to extend PAGER's near real-time capabilities beyond population exposure to quantitative estimates of fatalities, injuries, and displaced population.

  20. Estimate of the Potential Amount of Low-Level Waste from the Fukushima Prefecture - 12370

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hill, Carolyn; Olson, Eric A.J.; Elmer, John

    2012-07-01

    The amount of waste generated by the cleanup of the Fukushima Prefecture (Fukushima-ken) following the releases from the Fukushima Daiichi nuclear power plant accident (March 2011) is dependent on many factors, including: - Contamination amounts; - Cleanup levels determined for the radioisotopes contaminating the area; - Future land use expectations and human exposure scenarios; - Groundwater contamination considerations; - Costs and availability of storage areas, and eventually disposal areas for the waste; and - Decontamination and volume reduction techniques and technologies used. For the purposes of estimating these waste volumes, Fukushima-ken is segregated into zones of similar contamination level andmore » expected future use. Techniques for selecting the appropriate cleanup methods for each area are shown in a decision tree format. This approach is broadly applied to the 20 km evacuation zone and the total amounts and types of waste are estimated; waste resulting from cleanup efforts outside of the evacuation zone is not considered. Some of the limits of future use and potential zones where residents must be excluded within the prefecture are also described. The size and design of the proposed intermediate storage facility is also discussed and the current situation, cleanup, waste handling, and waste storage issues in Japan are described. The method for estimating waste amounts outlined above illustrates the large amount of waste that could potentially be generated by remediation of the 20 km evacuation zone (619 km{sup 2} total) if the currently proposed cleanup goals are uniformly applied. The Japanese environment ministry estimated in early October that the 1 mSv/year exposure goal would make the government responsible for decontaminating about 8,000 km{sup 2} within Fukushima-ken and roughly 4,900 km{sup 2} in areas outside the prefecture. The described waste volume estimation method also does not give any consideration to areas with localized hot