47 CFR 74.433 - Temporary authorizations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... identification number of the associated broadcast station or stations, call letters of remote pickup station (if..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Remote Pickup Broadcast Stations § 74.433 Temporary authorizations. (a) Special temporary authority may be granted for remote pickup station...

P and S Body Wave Tomography of the West Antarctic Rift System: Evidence for Recent Cenozoic Rifting

NASA Astrophysics Data System (ADS)

Soto, D. R.; Nyblade, A.; Anandakrishnan, S.; Aster, R. C.; Wiens, D.; Huerta, A. D.; Winberry, J. P.; Wilson, T. J.

2017-12-01

Imaging the upper mantle of West Antarctica can provide valuable information about its deep structure, the source of subglacial volcanism, and the age of rifting in the West Antarctic Rift System (WARS). The WARS extends across West Antarctica and is characterized by low sub-ice sheet topography, with the deepest area being the Bentley Subglacial Trench. Seismic data from POLENET/ANET broadband seismic stations were used to obtain improved body wave images of the upper mantle. The data comes from 34 backbone stations, 13 temporary broadband stations deployed across the WARS from the Whitmore Mountains to Marie Byrd Land from January 2010 to January 2012, 10 stations deployed above the Byrd Subglacial Basin from January 2015 to January 2017, and 5 stations from the UKANET network deployed January 2016 to the present. Using multi-channel cross correlation of P and S body waves from teleseismic earthquakes, travel time residuals have been obtained from 360 events for the P-wave model and 263 events for the S-wave model. The VanDecar's method of linear inversion method has been used to develop a model of relative P and S wave velocity variations in the upper mantle. Preliminary P and S wave models show a low velocity anomaly 150 km beneath Marie Byrd Land and faster wave speeds across much of the WARS, except for beneath the Bentley Subglacial Trench, where a modest low wave speed region is imaged. These results are consistent with previously published tomographic models of West Antarctica.

41 CFR 302-3.400 - What is a “temporary change of station (TCS)”?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false What is a âtemporary change of station (TCS)â? 302-3.400 Section 302-3.400 Public Contracts and Property Management Federal... TYPE Employee's Temporary Change Of Station § 302-3.400 What is a “temporary change of station (TCS...

41 CFR 302-3.400 - What is a “temporary change of station (TCS)”?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 41 Public Contracts and Property Management 4 2011-07-01 2011-07-01 false What is a âtemporary change of station (TCS)â? 302-3.400 Section 302-3.400 Public Contracts and Property Management Federal... TYPE Employee's Temporary Change Of Station § 302-3.400 What is a “temporary change of station (TCS...

Mammoth Mountain, California broadband seismic experiment

NASA Astrophysics Data System (ADS)

Dawson, P. B.; Pitt, A. M.; Wilkinson, S. K.; Chouet, B. A.; Hill, D. P.; Mangan, M.; Prejean, S. G.; Read, C.; Shelly, D. R.

2013-12-01

Mammoth Mountain is a young cumulo-volcano located on the southwest rim of Long Valley caldera, California. Current volcanic processes beneath Mammoth Mountain are manifested in a wide range of seismic signals, including swarms of shallow volcano-tectonic earthquakes, upper and mid-crustal long-period earthquakes, swarms of brittle-failure earthquakes in the lower crust, and shallow (3-km depth) very-long-period earthquakes. Diffuse emissions of C02 began after a magmatic dike injection beneath the volcano in 1989, and continue to present time. These indications of volcanic unrest drive an extensive monitoring effort of the volcano by the USGS Volcano Hazards Program. As part of this effort, eleven broadband seismometers were deployed on Mammoth Mountain in November 2011. This temporary deployment is expected to run through the fall of 2013. These stations supplement the local short-period and broadband seismic stations of the Northern California Seismic Network (NCSN) and provide a combined network of eighteen broadband stations operating within 4 km of the summit of Mammoth Mountain. Data from the temporary stations are not available in real-time, requiring the merging of the data from the temporary and permanent networks, timing of phases, and relocation of seismic events to be accomplished outside of the standard NCSN processing scheme. The timing of phases is accomplished through an interactive Java-based phase-picking routine, and the relocation of seismicity is achieved using the probabilistic non-linear software package NonLinLoc, distributed under the GNU General Public License by Alomax Scientific. Several swarms of shallow volcano-tectonic earthquakes, spasmodic bursts of high-frequency earthquakes, a few long-period events located within or below the edifice of Mammoth Mountain and numerous mid-crustal long-period events have been recorded by the network. To date, about 900 of the ~2400 events occurring beneath Mammoth Mountain since November 2011 have been relocated. Our goal is to derive high-resolution three-dimensional P- and S-wave velocity structure models of Mammoth Mountain. These models will enable more precise locations of the local seismicity, full waveform inversions of long-period seismicity, derivation of moment tensors for the seemingly brittle-failure high-frequency earthquakes, analyses of shear-wave splitting, and high-resolution relative relocation of seismicity using double differences.

47 CFR 25.277 - Temporary fixed earth station operations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for fewer...

47 CFR 25.277 - Temporary fixed earth station operations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 2 2013-10-01 2013-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for fewer...

47 CFR 25.277 - Temporary fixed earth station operations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 2 2012-10-01 2012-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for fewer...

47 CFR 25.277 - Temporary fixed earth station operations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 2 2014-10-01 2014-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for fewer...

47 CFR 25.277 - Temporary fixed earth station operations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Temporary fixed earth station operations. 25... SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.277 Temporary fixed earth station operations. (a) When an earth station in the Fixed-Satellite Service is to remain at a single location for fewer...

Earthquake Activity in the North Greenland Region

NASA Astrophysics Data System (ADS)

Larsen, Tine B.; Dahl-Jensen, Trine; Voss, Peter H.

2017-04-01

Many local and regional earthquakes are recorded on a daily basis in northern Greenland. The majority of the earthquakes originate at the Arctic plate boundary between the Eurasian and the North American plates. Particularly active regions away from the plate boundary are found in NE Greenland and in northern Baffin Bay. The seismograph coverage in the region is sparse with the main seismograph stations located at the military outpost, Stations Nord (NOR), the weather station outpost Danmarkshavn (DAG), Thule Airbase (TULEG), and the former ice core drilling camp (NEEM) in the middle of the Greenland ice sheet. Furthermore, data is available from Alert (ALE), Resolute (RES), and other seismographs in northern Canada as well as from a temporary deployment of BroadBand seismographs along the north coast of Greenland from 2004 to 2007. The recorded earthquakes range in magnitude from less than 2 to a 4.8 event, the largest in NE Greenland, and a 5.7 event, the largest recorded in northern Baffin Bay. The larger events are recorded widely in the region allowing for focal mechanisms to be calculated. Only a few existing focal mechanisms for the region can be found in the ISC bulletin. Two in NE Greenland representing primarily normal faulting and one in Baffin Bay resulting from reverse faulting. New calculations of focal mechanisms for the region will be presented as well as improved hypocenters resulting from analysis involving temporary stations and regional stations that are not included in routine processing.

The GANSSER seismological network in Bhutan

NASA Astrophysics Data System (ADS)

Hetényi, G.

2013-12-01

Our project investigates the Geodynamics ANd Seismic Structure of the Eastern-Himalaya Region (GANSSER). It aims to reveal the first seismological images beneath Bhutan and as such is a tribute to the late Augusto Gansser, geological discoverer of Bhutan [1]. Project GANSSER builds on the deployment of a temporary broadband seismometer network. This consists of 38 stations deployed across the Kingdom of Bhutan. Two south-north segments in the western and eastern part of the country constitute densely spaced lines of ca. 7 km inter-station distance with respectively 16 and 14 stations. The main technique to apply is receiver functions in order to image the Moho as it deepens from India to Tibet, thus revealing how the crust thickens in the Eastern Himalayas. Further 8 stations are located in-between these lines, in the central part of the country. The main purpose here is to characterize the seismicity of the country in a homogeneous manner. Altogether, the station network will allow the application of different classical seismological techniques, such as teleseismic, local earthquake, ambient noise and attenuation tomography. The dataset will also be exploited to try to locate landslides that cause a significant hazard, especially in and after the summer monsoon season. The station network described above has been deployed in January 2013 and is planned to operate until spring 2014. A first visit to the stations in April 2013 found operational conditions better than the average for temporary seismological networks. Data recovery in this time period exceeded 90%. Power spectral density diagrams indicate that the noise levels at our station sites are within the bounds of the Peterson Noise Model bounds [2] and in some cases are significantly less than the high-noise model. Starting April 2013 remote communications pathways with one third of the stations are tested. The scientific goals of Project GANSSER include: the determination of the structure and physical properties of the crust and the lithosphere; the mapping of seismic activity in the country and its eventual seasonal variation; joint interpretation with gravity data acquired in 2010-2012; landslide and debris flow detection and localization. Among the goals are the preliminary site tests in preparation for the permanent seismic observatory for Bhutan. Seismotectonic studies based on this project will compare different segments of the Himalayas and may shed light on the origin of the apparent seismic gap in Bhutan. The project will also play a role in building the basic knowledge towards mapping the seismic hazard in Bhutan within the next few years. This poster will present the station geometry, and preliminary information about the seismic data; it will also provide the opportunity to discuss the scientific objectives of the project with conference attendees. [1] A. Gansser, Geology of the Bhutan Himalayas (Birkhäuser, Basel, 1983), p 183. [2] J. Peterson, Observations and modelling of seismic background noise (USGS, Albuquerque, 1993)

Seismic anisotropy across the east African plateau from shear wave splitting analysis

NASA Astrophysics Data System (ADS)

Bagley, B. C.; Nyblade, A.; Mulibo, G.; Tugume, F.

2011-12-01

Previous studies of the east African plateau reveal complicated patterns of seismic anisotropy that are not easily explained by a single mechanism. The pattern is defined by rift-parallel fast directions for stations within or near Cenozoic rift valleys, and near-null results in Precambrian terrains away from the rift. Data from 65 temporary Africa Array stations deployed between 2007 and 2011 are being used to make new shear wave splitting measurements. The stations span the east African plateau and cover both the eastern and western branches of the east African rift system, as well as unrifted Proterozoic and Archean terrains in Uganda, Kenya, Tanzania, and Zambia. Through analysis of shear wave splitting we will better constrain the distribution of seismic anisotropy, and and from it gain new insight into the tectonic evolution of east Africa.

Borehole P- and S-wave velocity at thirteen stations in Southern California

USGS Publications Warehouse

Gibbs, James F.; Boore, David M.; Tinsley, John C.; Mueller, Charles S.

2001-01-01

The U.S. Geological Survey (USGS), as part of a program to acquire seismic velocity data at locations of strong-ground motion in earthquakes (e.g., Gibbs et al., 2000), has investigated thirteen additional sites in the Southern California region. Of the thirteen sites, twelve are in the vicinity of Whittier, California, and one is located in San Bernardino, California. Several deployments of temporary seismographs were made after the Whittier Narrows, California earthquake of 1 October 1987 (Mueller et al., 1988). A deployment, between 2 October and 9 November 1987, was the motivation for selection of six of the drill sites. Temporary portable seismographs at Hoover School (HOO), Lincoln School (LIN), Corps of Engineers Station (NAR), Olive Junior High School (OLV), Santa Anita Golf Course (SAG), and Southwestern Academy (SWA) recorded significant aftershock data. These portable sites, with the exception of Santa Anita Golf Course, were co-sited with strong-motion recorders. Stations at HOO, Lincoln School Whittier (WLB), Saint Paul High School (STP), Alisos Adult School (EXC), Cerritos College Gymnasium (CGM), Cerritos College Physical Science Building (CPS), and Cerritos College Police Building (CPB) were part of an array of digital strong-motion stations deployed from "bedrock" in Whittier to near the deepest part of the Los Angeles basin in Norwalk. Although development and siting of this new array (partially installed at the time of this writing) was generally motivated by the Whittier Narrows earthquake, these new sites (with the exception of HOO) were not part of any Whittier Narrows aftershock deployments. A similar new digital strong-motion site was installed at the San Bernardino Fire Station during the same time frame. Velocity data were obtained to depths of about 90 meters at two sites, 30 meters at seven sites, and 18 to 25 meters at four sites. Lithology data from the analysis of cuttings and samples was obtained from the two 90-meter deep holes and from five of the shallower holes to supplement the velocity interpretation. The two 90-meter boreholes (SB1, CPB) have been instrumented with borehole seismometers for continuous monitoring of earthquake activity (Rogers et al., 1998). No drill samples or cuttings were obtained from the other six sites, but driller's logs were scanned for major changes noted there. The velocity models at those sites were interpreted using only the measured data and major changes in the driller's log as noted above. The sites are shown in Figure 1 and listed in Table 1, which gives references to information regarding the strong-motion data. Several hundred strong-motion records of the main-shock were written by this moderate size earthquake (ML = 5.9), making it important from a scientific and engineering prospective (Brady et al., 1988; Shakal et al., 1988).

Seismic Tomography of the South Carpathian System

NASA Astrophysics Data System (ADS)

Stuart, G. W.; Ren, Y.; Dando, B. D.; Houseman, G.; Ionescu, C.; Hegedus, E.; Radovanovic, S.; South Carpathian Project Working Group

2010-12-01

The South Carpathian Mountain Range is an enigmatic system, which includes one of the most seismically active regions in Europe today. That region, Vrancea in the SE Carpathians, is well studied and its deep structure may be geologically unique, but the mantle structures beneath the western part of the South Carpathian Range are not well resolved by previous tomographic studies. The South Carpathian Project (SCP) is a major temporary deployment (2009-2011) of seismic broadband systems extending across the eastern Pannonian Basin and the South Carpathian Mountains. In this project we aim to map the upper mantle structure in central Europe with the objective of testing geodynamic models of the process that produced extension in the Pannonian, synchronous with convergence and uplift in the Carpathians. Here, we describe initial results of finite-frequency tomography using body waves to image the mantle of the region. We have selected teleseismic earthquakes with magnitude greater than 5.9, which occurred between 2005 and 2010. The data were recorded on 57 temporary stations deployed in the South Carpathian Project, 56 temporary stations deployed in the earlier Carpathian Basins Project (CBP), and 41 permanent broadband stations. The differential travel times are measured in high, intermediate and low frequencies (0.5-2.0 Hz, 0.1-0.5 Hz and 0.03-0.1 Hz for both P-wave, 0.1-0.5 Hz, 0.05-0.1 Hz and 0.02-0.05 Hz for S-wave), and are inverted to produce P and S-wave velocity maps at different depths in the mantle. An extensive zone of high seismic velocities is located in the Mantle Transition zone beneath the Pannonian Basin, and is related to down-welling associated with an earlier phase of continental convergence in the Pannonian region. These results will be used in conjunction with 3D geodynamical modelling to help understand the geological evolution of this region. SCP working group: G. Houseman, G. Stuart, Y. Ren, B. Dando, P. Lorinczi, School of Earth and Environment, University of Leeds, UK; E. Hegedus, A. Kovács, I. Török, I. László, R. Csabafi, Eötvös Loránd Geophysical Institute, Budapest, Hungary; C. Ionescu, M. Radulian, V. Raileanu, D. Tataru, B. Zaharia, F. Borleanu, C. Neagoe, G. Gainariu, National Institute of Earth Physics, Bucharest, Romania; S. Radovanovic, V. Kovacevic, D. Valcic, S. Petrovic-Cacic, G. Krunic, Seismological Survey of Serbia, Belgrade, Serbia; A. Brisbourne, D. Hawthorn, V. Lane, SEIS-UK, Leicester University, UK.

Deployable Crew Quarters

NASA Technical Reports Server (NTRS)

Izenson, Michael G.; Chen, Weibo

2008-01-01

The deployable crew quarters (DCQ) have been designed for the International Space Station (ISS). Each DCQ would be a relatively inexpensive, deployable boxlike structure that is designed to fit in a rack bay. It is to be occupied by one crewmember to provide privacy and sleeping functions for the crew. A DCQ comprises mostly hard panels, made of a lightweight honeycomb or matrix/fiber material, attached to each other by cloth hinges. Both faces of each panel are covered with a layer of Nomex cloth and noise-suppression material to provide noise isolation from ISS. On Earth, the unit is folded flat and attached to a rigid pallet for transport to the ISS. On the ISS, crewmembers unfold the unit and install it in place, attaching it to ISS structural members by use of soft cords (which also help to isolate noise and vibration). A few hard pieces of equipment (principally, a ventilator and a smoke detector) are shipped separately and installed in the DCQ unit by use of a system of holes, slots, and quarter-turn fasteners. Full-scale tests showed that the time required to install a DCQ unit amounts to tens of minutes. The basic DCQ design could be adapted to terrestrial applications to satisfy requirements for rapid deployable emergency shelters that would be lightweight, portable, and quickly erected. The Temporary Early Sleep Station (TeSS) currently on-orbit is a spin-off of the DCQ.

Seismic Data for Evaluation of Ground Motion Hazards in Las Vegas in Support of Test Site Readiness Ground Motion

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

Rodgers, A

2008-01-16

In this report we describe the data sets used to evaluate ground motion hazards in Las Vegas from nuclear tests at the Nevada Test Site. This analysis is presented in Rodgers et al. (2005, 2006) and includes 13 nuclear explosions recorded at the John Blume and Associates network, the Little Skull Mountain earthquake and a temporary deployment of broadband station in Las Vegas. The data are available in SAC format on CD-ROM as an appendix to this report.

Infrasonic observations of large-scale HE events

NASA Technical Reports Server (NTRS)

Whitaker, Rodney W.; Mutschlecner, J. Paul; Davidson, Masha B.; Noel, Susan D.

1990-01-01

The Los Alamos Infrasound Program has been operating since about mid-1982, making routine measurements of low frequency atmospheric acoustic propagation. Generally, the authors work between 0.1 Hz to 10 Hz; however, much of the work is concerned with the narrower range of 0.5 to 5.0 Hz. Two permanent stations, St. George, UT, and Los Alamos, NM, have been operational since 1983, collecting data 24 hours a day. For the purposes of this discussion, the authors concentrate on their measurements of large, high explosive (HE) events at ranges of 250 km to 5330 km. Because their equipment is well suited for mobile deployments, they can easily establish temporary observing sites for special events. The measurements are from the permanent sites, as well as from various temporary sites. A few observations that are typical of the full data set are given.

47 CFR 101.815 - Stations at temporary fixed locations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary...

47 CFR 101.815 - Stations at temporary fixed locations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary...

47 CFR 101.815 - Stations at temporary fixed locations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary...

47 CFR 101.815 - Stations at temporary fixed locations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary...

47 CFR 101.815 - Stations at temporary fixed locations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Stations at temporary fixed locations. 101.815 Section 101.815 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.815 Stations at temporary...

What many years of tremor reveals about the Mexican Sweet Spot

NASA Astrophysics Data System (ADS)

Husker, A. L.; Avila, L.; Gonzalez, G.; Frank, W.; Kostoglodov, V.

2017-12-01

Different temporary seismic deployments have detected and located tectonic tremor in Mexico. These different temporary studies have lasted for a maximum of a few years. However, the long-term SSE's occur every 4 years. The permanent network is too sparse to locate SSEs, however one station is located in the main tremor region and has very low noise. We use spectral detection to create a catalog from its installation in March 2009 to the present. The catalog corresponds with the catalog determined during the temporary GGAP seismic network deployment, which gives us confidence that the single station detection works. Two separate large long term SSEs (2009-2010 and 2014) occur in this time span. We find a good correlation between the tremor and slip at the beginning of the SSEs. However, we find differences in both in the later stages of the SSEs. The 2009-2010 SSE appeared to be ending towards the end of 2009, however it was reactivated by the Feb. 27, 2010 M8.8 Chilean earthquake. The tremor showed a small many day burst (similar to other bursts) associated with the earthquake, but did not resume the high continuous tremor rate associated with the beginning of the SSE or seen during other large SSEs. The tremor rate at the end of the 2014 SSE stayed high for many months after the SSE and did not return to the background inter-SSE rate until the middle of 2015, about 6 months after the SSE ended. The background tremor rate is roughly 1 hour/day and remains constant over the entire period. This rate is actually comprised of many bursts that can last for up to 2 weeks with up to 80 hours of tremor during that time. The very constant long-term tremor rate made up of bursts can be explained by a simple stick-slip model.

Dynamic Triggering around Fangshan Pluton near Beijing,China

NASA Astrophysics Data System (ADS)

Wang, W.; Gong, X.; Peng, Z.; Chen, Q.; Wu, C.

2011-12-01

Fangshan Pluton lies at SW of Beijing City and is formed at about 133-128Ma. The Pluton is surrounded by the NNE-trending Taihang mountain in the west as an "C" shape, and is in conjunction with the Northern China Plain along the Baobashan fault in the east. This region currently does not have abundant background seismicity, but previous studies (Peng et al., 2010, Wu et al. 2011) have shown that at least 4 major earthquakes in East Asia have triggered clear seismic events in this region. To further understand the dynamic triggering mechanism and improve the station coverage, we deployed the first batch temporal seismic array with 5 stations from 12/2008 to 7/2010 and the second batch with 11 stations around this area since 12/2010. Our temporary deployment was fortunate to capture the triggered seismicity following the 2011 Mw9.0 Tohoku-Oki, Japan, earthquake sequence. In this study, we use seismic data recorded by the permanent stations in the Capital Circle seismic network and our temporary deployment to investigate triggered seismicity following the 2010 Mw8.8 Chile earthquake and the Tohoku-Oki earthquake sequence. As was done before, we identify triggered earthquakes as impulsive seismic arrivals with clear P- and S-waves in 5 Hz high-pass-filtered three-component velocity seismograms and recorded by at least 3 stations. Most triggered earthquakes coincide with the large-amplitude Rayleigh waves. For the Tohoku-Oki case, we identify one weak event during the P-wave of the mainshock, and delayed triggering following the large-amplitude surface waves. In addition, triggered earthquakes can be seen in the Mw7.3 foreshock and mainshock of Tohoku earthquake, but not in aftershocks with 2 Mw>7.5 earthquakes in the following two months. These events mainly occurred at southwestern and western boundary region of the Pluton and are shallower (<5km) than normal earthquakes, which is similar to previous studies. Considering the abundant solution cavities and syncline/anticline structures developed during the magma intrusion, we suggest that the triggered earthquakes could occur at the weak boundary regions with abundant underground water that permeate into deep layer through the cracked syncline tips or faults. Our next step is to locate the triggered and background seismicity more precisely, and determine the focal mechanisms of the triggered events for better understanding of the source faults and necessary conditions for dynamic triggering in this region.

Deployment Health

DTIC Science & Technology

2006-08-11

thermo luminescent dosimeter ( TLD badge)) are required for performing specific tasks in a safe manner while deployed, personnel must be trained on the...monitoring devices (e.g., thermo luminescent dosimeter ( TLD badge)) as required by occupational specialty of personnel. (E4.A1.1.5.) 5.5.8 X X...assigned, attached, on temporary duty, or temporary additional duty to deployed units. Report the data electronically to the DMDC (at the SECRET level

Investigation of the lithosphere of the Texas Gulf Coast using phase-specific Ps receiver functions produced by wavefield iterative deconvolution

NASA Astrophysics Data System (ADS)

Gurrola, H.; Berdine, A.; Pulliam, J.

2017-12-01

Interference between Ps phases and reverberations (PPs, PSs phases and reverberations thereof) make it difficult to use Ps receiver functions (RF) in regions with thick sediments. Crustal reverberations typically interfere with Ps phases from the lithosphere-asthenosphere boundary (LAB). We have developed a method to separate Ps phases from reverberations by deconvolution of all the data recorded at a seismic station by removing phases from a single wavefront at each iteration of the deconvolution (wavefield iterative deconvolution or WID). We applied WID to data collected in the Gulf Coast and Llano Front regions of Texas by the EarthScope Transportable array and by a temporary deployment of 23 broadband seismometers (deployed by Texas Tech and Baylor Universities). The 23 station temporary deployment was 300 km long; crossing from Matagorda Island onto the Llano uplift. 3-D imaging using these data shows that the deepest part of the sedimentary basin may be inboard of the coastline. The Moho beneath the Gulf Coast plain does not appear in many of the images. This could be due to interference from reverberations from shallower layers or it may indicate the lack of a strong velocity contrast at the Moho perhaps due to serpentinization of the uppermost mantle. The Moho appears to be flat, at 40 km) beneath most of the Llano uplift but may thicken to the south and thin beneath the Coastal plain. After application of WID, we were able to identify a negatively polarized Ps phase consistent with LAB depths identified in Sp RF images. The LAB appears to be 80-100 km deep beneath most of the coast but is 100 to 120 km deep beneath the Llano uplift. There are other negatively polarized phases between 160 and 200 km depths beneath the Gulf Coast and the Llano Uplift. These deeper phases may indicate that, in this region, the LAB is transitional in nature and rather than a discrete boundary.

Hurricane Irene's Impacts on the Aftershock Sequence of the 2011 Mw5.8 Virginia Earthquake

NASA Astrophysics Data System (ADS)

Meng, X.; Peng, Z.; Yang, H.; Allman, S.

2013-12-01

Recent studies have shown that typhoon could trigger shallow slow-slip events in Taiwan. However, it is unclear whether such extreme weather events could affect the occurrence of regular earthquakes as well. A good opportunity to test this hypothesis occurred in 2011 when an Mw 5.8 earthquake struck Louisa County, Virginia. This event ruptured a shallow, reverse fault. Roughly 5 days later, hurricane Irene struck the coast of Norfolk, Virginia, which is near the epicentral region of the Virginia mainshock. Because aftershocks listed in the ANSS catalog were incomplete immediately after the main shock, it is very difficult to find the genuine correlation between the seismicity rate changes and hurricane Irene. Hence, we use a recently developed waveform matched filter technique to scan through the continuous seismic data to detect small aftershocks that are previously unidentified. A mixture of 7 temporary stations from the IRIS Ramp deployment and 8 temporary stations deployed by Virginia Tech is used. The temporary stations were set up between 24 to 72 hours following the main shock around its immediate vicinity, which provides us a unique dataset recording the majority aftershock sequence of an intraplate earthquake. We us 80 aftershocks identified by Chapman [2013] as template events and scan through the continuous data from 23 August 2011 through 10 September 2011. So far, we have detected 704 events using a threshold of 12 times the median absolute deviation (MAD), which is ~25 times more than listed in the ANSS catalog. The aftershock rate generally decayed with time as predicted by the Omori's law. A statistically significant increase of seismicity rate is found when hurricane Irene passed by the epicentral region. A possible explanation is that the atmosphere pressure drop unloaded the surface, which brought the reverse faults closer to failure. However, we also identified similar fluctuations of seismicity rate changes at other times. Hence, it is still possible that the seismicity rate increase during the hurricane Irene's passing by could be by coincidence. We are currently in the process of relocating all the newly detected events and investigate if any aftershock migration pattern might relate to the path of hurricane Irene. If true, it would suggest that extreme weather events such as hurricanes could trigger not only slow-slip events, but also regular earthquakes.

UMTS rapid response real-time seismic networks: implementation and strategies at INGV

NASA Astrophysics Data System (ADS)

Govoni, Aladino; Margheriti, Lucia; Moretti, Milena; Lauciani, Valentino; Sensale, Gianpaolo; Bucci, Augusto; Criscuoli, Fabio

2015-04-01

The benefits of portable real-time seismic networks are several and well known. During the management of a temporary experiment from the real-time data it is possible to detect and fix rapidly problems with power supply, time synchronization, disk failures and, most important, seismic signal quality degradation due to unexpected noise sources or sensor alignment/tampering. This usually minimizes field maintenance trips and maximizes both the quantity and the quality of the acquired data. When the area of the temporary experiment is not well monitored by the local permanent network, the real-time data from the temporary experiment can be fed to the permanent network monitoring system improving greatly both the real-time hypocentral locations and the final revised bulletin. All these benefits apply also in case of seismic crises when rapid deployment stations can significantly contribute to the aftershock analysis. Nowadays data transmission using meshed radio networks or satellite systems is not a big technological problem for a permanent seismic network where each site is optimized for the device power consumption and is usually installed by properly specialized technicians that can configure transmission devices and align antennas. This is not usually practical for temporary networks and especially for rapid response networks where the installation time is the main concern. These difficulties are substantially lowered using the now widespread UMTS technology for data transmission. A small (but sometimes power hungry) properly configured device with an omnidirectional antenna must be added to the station assembly. All setups are usually configured before deployment and this allows for an easy installation also by untrained personnel. We describe here the implementation of a UMTS based portable seismic network for both temporary experiments and rapid response applications developed at INGV. The first field experimentation of this approach dates back to the 2009 L'Aquila aftershock sequence and since then it has been customized and refined to overcome most reliability and security issues using an industry standard VPN architecture that allows to avoid UMTS provider firewall problems and does not expose to the Internet the usually weak and attack prone data acquisition ports. With this approach all the devices are protected inside a local network and the only exposed port is the VPN server one. This solution improves both the security and the bandwidth available to data transmission. While most of the experimentation has been carried out using the RefTek units of the INGV Mobile Network this solution applies equally well to most seismic data loggers available on the market. Overall the UMTS data transmission has been used in most temporary seismic experiments and in all seismic emergencies happened in Italy since 2010 and has proved to be a very cost effective approach with real-time data acquisition rates usually greater than 97% and all the benefits that result from the fast integration of the temporary data in the National Network monitoring system and in the EIDA data bank.

Improving the resolution of the 2010 Haiti earthquake fault geometry using temporary seismometer deployments

NASA Astrophysics Data System (ADS)

Douilly, R.; Haase, J. S.; Ellsworth, W. L.; Bouin, M.; Calais, E.; Armbruster, J. G.; Mercier De Lepinay, B. F.; Deschamps, A.; Saint Louis, M.; Meremonte, M. E.; Hough, S. E.

2011-12-01

Haiti has several active faults that are capable of producing large earthquakes such as the 2010 Mw 7.0 Haiti earthquake. This earthquake was not unexpected, given geodetic measurements showing strain accumulation on the Enriquillo Plantain Garden Fault Zone, the major fault system in southern Haiti (Manaker et al. 2008). GPS and INSAR data (Calais et al., 2010) show, however, that this rupture occurred on the previously unmapped Léogâne fault, a 60° north dipping oblique blind thrust located immediately north of the Enriquillo Fault. Following the earthquake, several groups installed temporary seismic stations to record aftershocks. Natural Resources Canada installed three broadband seismic stations, Géoazur installed 21 ocean bottom seismometers, L'Institut de Physique du Globe de Paris installed 5 broadband seismometers, and the United States Geological Survey deployed 17 short period and strong motion seismometers in and around Port-au-Prince. We use data from this complete set of stations, along with data from permanent regional stations, to relocate all of the events from March 17 to June 24, to determine the regional one-dimensional crustal structure and determine focal mechanisms. The aftershock locations from the combined data set clearly delineate the Léogâne fault. The strike and dip closely agrees with that of the global centroid moment tensor solution, but appears to be more steeply dipping than the finite fault inversions. The aftershocks also delineate a flat structure on the west side of the rupture zone and may indicate triggered seismicity on the Trois Baies fault, although the depths of these events are not as well constrained. There is no clear evidence for aftershocks on the other rupture segments inferred in the Hayes et al. (2010) mainshock rupture model. There is a cluster of aftershocks in the hanging wall near the western patch of high slip identified by Calais et al. (2010) and Meng et al. (2011), or central patch in the Hayes et al. (2010) model. We use first-motion focal mechanism solutions to clarify the relationship of the fault geometry to the mechanisms of the larger events.

Emergency seismic and CGPS networks: a first employment for the L'Aquila Mw 6.3 earthquake

NASA Astrophysics Data System (ADS)

Abruzzese, L.; Avallone, A.; Cecere, G.; Cattaneo, M.; Cardinale, V.; Castagnozzi, A.; Cogliano, R.; Criscuoli, F.; D'Agostino, N.; D'Ambrosio, C.; de Luca, G.; D'Anastasio, E.; Falco, L.; Flammia, V.; Migliari, F.; Minichiello, F.; Memmolo, A.; Monachesi, G.; Moschillo, R.; Pignone, M.; Pucillo, S.; Selvaggi, G.; Zarrilli, L.; Delladio, A.; Govoni, A.; Franceschi, D.; de Martin, M.; Moretti, M.

2009-12-01

During the last 2 years, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) developed an important real-time temporary seismic network infrastructure in order to densify the Italian National Seismic Network in epicentral areas thus enhancing the localization of the micro-seismicity after main earthquake events. This real-time temporary seismic network is constituted by various mobile and autonomous seismic stations that in group of three are telemetered to a Very Small Aperture Terminal (VSAT). This system uses a dedicated bandwidth on UHF, Wi-Fi and satellite frequency that allows the data flow in real-time at INGV centre in Rome (and Grottaminarda as backup center). The deployment of the seismic network is managed in a geographical information systems (GIS) by particular scenarios that visualizes, for the epicentral area, information about instrumental seismicity, seismic risk, macroseismic felts and territorial data. Starting from digital terrain model, the surface spatial analysis (Viewshed, Observer Point) allows the geographic arrangement of the stations and relative scenarios. The April, 6th, 2009 Mw 6.3 L'Aquila destructive earthquake represented the first real-case to test the entire emergency seismic network infrastructure. Less than 6 hours after the earthquake occurrence, a first accelerometer station was already sending data at INGV seismic monitoring headquarters. A total number of 9 seismic stations have been installed within 3 days after the earthquake. Furthermore, 5 permanent GPS stations have been installed in the epicentral area within 1 to 9 days after the main shock to detect the post-seismic deformation induced by the earthquake. We will show and describe the details of the Emergency Seismic Network infrastructure, and the first results from the collected data.

Data quality control and tools in passive seismic experiments exemplified on the Czech broadband seismic pool MOBNET in the AlpArray collaborative project

NASA Astrophysics Data System (ADS)

Vecsey, Luděk; Plomerová, Jaroslava; Jedlička, Petr; Munzarová, Helena; Babuška, Vladislav; AlpArray Working Group

2017-12-01

This paper focuses on major issues related to the data reliability and network performance of 20 broadband (BB) stations of the Czech (CZ) MOBNET (MOBile NETwork) seismic pool within the AlpArray seismic experiments. Currently used high-resolution seismological applications require high-quality data recorded for a sufficiently long time interval at seismological observatories and during the entire time of operation of the temporary stations. In this paper we present new hardware and software tools we have been developing during the last two decades while analysing data from several international passive experiments. The new tools help to assure the high-quality standard of broadband seismic data and eliminate potential errors before supplying data to seismological centres. Special attention is paid to crucial issues like the detection of sensor misorientation, timing problems, interchange of record components and/or their polarity reversal, sensor mass centring, or anomalous channel amplitudes due to, for example, imperfect gain. Thorough data quality control should represent an integral constituent of seismic data recording, preprocessing, and archiving, especially for data from temporary stations in passive seismic experiments. Large international seismic experiments require enormous efforts from scientists from different countries and institutions to gather hundreds of stations to be deployed in the field during a limited time period. In this paper, we demonstrate the beneficial effects of the procedures we have developed for acquiring a reliable large set of high-quality data from each group participating in field experiments. The presented tools can be applied manually or automatically on data from any seismic network.

Crustal structure and fault geometry of the 2010 Haiti earthquake from temporary seismometer deployments

USGS Publications Warehouse

Douilly, Roby; Haase, Jennifer S.; Ellsworth, William L.; Bouin, Marie‐Paule; Calais, Eric; Symithe, Steeve J.; Armbruster, John G.; Mercier de Lépinay, Bernard; Deschamps, Anne; Mildor, Saint‐Louis; Meremonte, Mark E.; Hough, Susan E.

2013-01-01

Haiti has been the locus of a number of large and damaging historical earthquakes. The recent 12 January 2010 Mw 7.0 earthquake affected cities that were largely unprepared, which resulted in tremendous losses. It was initially assumed that the earthquake ruptured the Enriquillo Plantain Garden fault (EPGF), a major active structure in southern Haiti, known from geodetic measurements and its geomorphic expression to be capable of producing M 7 or larger earthquakes. Global Positioning Systems (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data, however, showed that the event ruptured a previously unmapped fault, the Léogâne fault, a north‐dipping oblique transpressional fault located immediately north of the EPGF. Following the earthquake, several groups installed temporary seismic stations to record aftershocks, including ocean‐bottom seismometers on either side of the EPGF. We use data from the complete set of stations deployed after the event, on land and offshore, to relocate all aftershocks from 10 February to 24 June 2010, determine a 1D regional crustal velocity model, and calculate focal mechanisms. The aftershock locations from the combined dataset clearly delineate the Léogâne fault, with a geometry close to that inferred from geodetic data. Its strike and dip closely agree with the global centroid moment tensor solution of the mainshock but with a steeper dip than inferred from previous finite fault inversions. The aftershocks also delineate a structure with shallower southward dip offshore and to the west of the rupture zone, which could indicate triggered seismicity on the offshore Trois Baies reverse fault. We use first‐motion focal mechanisms to clarify the relationship of the fault geometry to the triggered aftershocks.

Hydraulically Induced Seismicity in South-Eastern Brazil Linked to Water Wells

NASA Astrophysics Data System (ADS)

Convers, J.; Assumpcao, M.; Barbosa, J. R.

2017-12-01

While hydraulic stimulus on seismic activity is most commonly associated with hydraulic fracturing processes, we find in SE Brazil a rare case of seismicity influenced by hydraulic stimulation linked to seasonal rain and water wells in a farming area. These are thought to be the main factors influencing the seasonal seismicity activity in Jurupema, a farming town located in the interior of the state of Sao Paulo, southern Brazil. With temporary seismic station deployments during 2016 and 2017, we analyze the seismicity in this area, its temporal and spatial distribution, and its association with the drilling of ground water wells in this particular area. In a region where water wells are often drilled to provide irrigation for farming, these are often perforated down to about 100 m depth, penetrating below the uppermost sandstone rock layer ( 50 m) into a fractured basaltic rock layer, reaching the confined aquifer within it. While the wells are constantly pumped during the dry season, during the course of the rainy season (when these are not being used), a possible infiltration into the confined basaltic aquifer, from both the rainwater and the upper sandstone aquifer, adds changes to the pore pressure of the fractured rock, and modifies the tectonic pre-stress conditions, to facilitate stress release mechanisms in pre-existing faults and cracks. With our temporary seismic station deployments, we not only examine the seismicity in this region during both 2016 and 2017, but we additionally compare its characteristics to the nearby Bebedouro case in an apparent induced seismic case of analogous source, and seismic activity with magnitudes up to 2.9 occurring between 2005 and 2010.

Broadening the Quality and Capabilities of the EarthScope Alaska Transportable Array

NASA Astrophysics Data System (ADS)

Busby, R. W.

2016-12-01

In 2016, the EarthScope Transportable Array (TA) program will have 195 broadband seismic stations operating in Alaska and western Canada. This ambitious project will culminate in a network of 268 new or upgraded real-time seismic stations operating through 2019. The challenging environmental conditions and the remoteness of Alaska have motivated a new method for constructing a high-quality, temporary seismic network. The Alaska TA station design builds on experience of the Lower 48 TA deployment and adds design requirements because most stations are accessible only by helicopter. The stations utilize new high-performance posthole sensors, a specially built hammer/auger drill, and lightweight lithium ion batteries to minimize sling loads. A uniform station design enables a modest crew to build the network on a short timeline and operate them through the difficult conditions of rural Alaska. The Alaska TA deployment has increased the quality of seismic data, with some well-sited 2-3 m posthole stations approaching the performance of permanent Global Seismic Network stations emplaced in 100 m boreholes. The real-time data access, power budget, protective enclosure and remote logistics of these TA stations has attracted collaborations with NASA, NOAA, USGS, AVO and other organizations to add auxiliary sensors to the suite of instruments at many TA stations. Strong motion sensors have been added to (18) stations near the subduction trench to complement SM stations operated by AEC, ANSS and GSN. All TA and most upgraded stations have pressure and infrasound sensors, and 150 TA stations are receiving a Vaisala weather sensor, supplied by the National Weather Service Alaska Region and NASA, capable of measuring temperature, pressure, relative humidity, wind speed/direction, and precipitation intensity. We are also installing about (40) autonomous soil temperature profile kits adjacent to northern stations. While the priority continues to be collecting seismic data, these additional strong motion, atmospheric, and soil temperature sensors may motivate the desire extend the operation of certain stations in cooperation with these organizations. The TA has always been amenable to partnerships in the research and education communities that extend the capabilities and reach of the EarthScope Transportable Array.

Temporary Seismic Installation in Eastern Bangladesh: Microseismicity and Structure of an On-Land Accretionary Prism

NASA Astrophysics Data System (ADS)

Foster, A. E.; Almeida, R. V.; Akhter, S. H.; Hubbard, J.; Bhattacharya, R.; Shing, U. M.; Hosain, A.; Bulbul, M. A.

2016-12-01

Eastern Bangladesh is underlain by a fold and thrust belt accumulating 13-17 mm/yr of plate convergence on a locked, shallowly dipping décollement (Steckler et al., 2016). We have installed a network of short-period and broadband instruments in this region to better assess microseismicity and investigate the structure of the fold belt. Stations will remain in place for 1-2 years and will complement the temporary stations installed by the University of Dhaka and the Lamont-Doherty Earth Observatory. Thirteen Lennartz 1-Hz instruments and three Trillium Compact 120-s instruments were installed in the Sylhet area in June 2016. Station spacing is between 15-30 km. Installations ranged from shallow vaults to above-ground locations on solid foundations, as required by local conditions. One focus of this deployment is to locate microseismicity. Neither large numbers nor magnitudes of earthquakes are expected in this area, but improved locations may help define active areas of the convergence as well as illuminate the interactions between the Dauki fault (responsible for uplift of the Shillong Plateau), the Sylhet anticline, and the rest of the Indo-Burman Ranges. Nine additional short-period instruments and three additional broadband instruments will be installed in the Chittagong area in September 2016. The southern-most stations are located over the Andaman subduction zone, thought to be associated with a large subduction earthquake in 1762 (Steckler et al., 1998). Thus, the full deployment will span the transition from an on-land accretionary prism to an area considered a classic subduction zone. Combined, the northern and southern parts of the network should provide good locations for events within the Tripura area (India) as well. We present initial estimates of station quality and the potential for an earthquake catalogue. We plan to obtain earthquake locations and focal mechanisms, when possible, as the data is collected. We will apply ambient noise tomography methods to investigate the structure of the fold belt. These applications and others may contribute to unanswered questions in the area, such as the location of the frontal-most deformation associated with the fold and thrust belt and the geometry of the basal décollement at depth, and allow better characterization of the risk to nearby populations.

Models of lithosphere and asthenosphere anisotropic structure of the Yellowstone hot spot from shear wave splitting

USGS Publications Warehouse

Waite, Gregory P.; Schutt, D.L.; Smith, Robert B.

2005-01-01

Teleseismic shear wave splitting measured at 56 continuous and temporary seismographs deployed in a 500 km by 600 km area around the Yellowstone hot spot indicates that fast anisotropy in the mantle is parallel to the direction of plate motion under most of the array. The average split time from all stations of 0.9 s is typical of continental stations. There is little evidence for plume-induced radial strain, suggesting that any contribution of gravitationally spreading plume material is undetectably small with respect to the plate motion velocity. Two stations within Yellowstone have splitting measurements indicating the apparent fast anisotropy direction (ϕ) is nearly perpendicular to plate motion. These stations are ∼30 km from stations with ϕ parallel to plate motion. The 70° rotation over 30 km suggests a shallow source of anisotropy; however, split times for these stations are more than 2 s. We suggest melt-filled, stress-oriented cracks in the lithosphere are responsible for the anomalous ϕ orientations within Yellowstone. Stations southeast of Yellowstone have measurements of ϕ oriented NNW to WNW at high angles to the plate motion direction. The Archean lithosphere beneath these stations may have significant anisotropy capable of producing the observed splitting.

The AlpArray Seismic Network: status and operation

NASA Astrophysics Data System (ADS)

Hetényi, György; Molinari, Irene; Clinton, John; Kissling, Edi

2017-04-01

The AlpArray initiative (http://www.alparray.ethz.ch) is a large-scale European collaboration to study the entire Alpine orogen at high resolution and in 3D with a large variety of geoscientific methods. The core element of the initiative is an extensive and dense broadband seismological network, the AlpArray Seismic Network (AASN). Over 300 temporary stations complement the permanent seismological stations to ensure homogeneous coverage of the greater Alpine area. The AASN has officially started operation in January 2016 and is now complete on land. It is operated in a joint effort by a number of institutions from Austria, Bosnia-Herzegovina, Croatia, Czech Republic, France, Germany, Hungary, Italy, Slovakia and Switzerland. In the Ligurian Sea, a 32-station OBS campaign is planned from June 2017 until March 2018. This will complete the coverage of the greater Alpine area at an unprecedented resolution. In this poster we present the actual status of the deployment, the effort undertaken by the contributing groups, station performance, best practices, data management as well as often encountered challenges, and provide a meeting and discussion point during the conference.

Strategy for the deployment of a dense broadband temporary array in the Alps: lessons learnt from the CIFALPS experiment

NASA Astrophysics Data System (ADS)

Coralie, Aubert; Anne, Paul; Stefano, Solarino; Sandrine, Roussel; Simone, Salimbeni; Pierre, Zangelmi; Glenn, Cougoulat; Yinshuang, Ai; Weiwei, Xu; Yumei, He; Liang, Zhao

2013-04-01

The CIFALPS (China-Italy-France Alps seismic survey) experiment is a common project of IGGCAS (China), ISTerre (France) and INGV (Italy). It aims at getting new high-resolution passive seismic data on the crustal and upper mantle structure of the southwestern Alps. In this framework, we have installed a temporary broadband seismic array across the southwestern Alps from the Rhône valley (France) to the Po plain (Italy). The main sub-array of CIFALPS is a 350-km long roughly linear profile of 46 stations trending WSW-ENE from Bollène (France) to north of Alessandria (Italy). The average station spacing is 10 km in the outer parts of the belt, and it reduces to 5 km in the internal Alps. Nine additional temporary stations located ~40 km to the north and south of the main profile complement the permanent broadband networks to improve the 3-D constraints on the deep structures. Stations are equipped with Nanometrics Taurus data acquisition systems, and Trillium 120P/A, CMG3-ESP or CMG40T broadband sensors. The array was installed in the summer of 2012 and will be operated at least to April 2013. Because our schedule was tight, we had to achieve site selections in only 3-4 months in spite of strong constraints on site location related to short interstation spacing. Most sites are located in basements of buildings for security reasons and mains power supply. As most sensors are true broadband (90s or 120s), we put much effort on vault design to insure good thermal insulation and low noise at long periods. The vaults also had to be easily and rapidly built and they should be easily and totally removed at the end of the experiment. We used the PQLX software for quality control of our sites and vault design. The performances of our vaults are good for the vertical component with noise levels at 100s period in the range -185 dB (low noise model) to -165 dB. They are less good for horizontal components (noise level close to high noise model at periods > 20s) due to atmospheric pressure and temperature variations. Stations located outside buildings do not have better performances at 100s than stations located in basements. Two of our six stations installed outside buildings are prone to mass centering problems due to tilting of the concrete slab in soft soil. For state-of-health control and data transmission, we are testing 2G and 3G communication modems at 4 remote stations but with limited success. Database preparation and management benefitted from the expertise of engineers of the seismic datacenter of ISTerre. The experience gained on all technical aspects of a temporary experiment will provide valuable input for the preparation of the future AlpArray project.

Parental Incarceration, Transnational Migration, and Military Deployment: Family Process Mechanisms of Youth Adjustment to Temporary Parent Absence

PubMed Central

Rodriguez, Aubrey J.; Margolin, Gayla

2015-01-01

The temporary absence of a parent (e.g., due to incarceration, migration, or military deployment) is experienced by many youth and can have profound effects. Available research within these disparate literatures primarily has catalogued contextual and individual variables that influence youth adaptation, which are integrated and summarized here. In addition, we present a systematic review of proximal family process mechanisms by which youth and their family members adapt to periods of temporary parent absence. This systematic review across the different types of parent absence produced four themes: communication among family members, parenting characteristics during absence, negotiation of decision-making power and authority, and shifts in family roles. By juxtaposing the three types of temporary parent absence, we aim to bridge the separate research silos of parent absence due to incarceration, deployment, and migration, and to bring wide-ranging characteristics and processes of temporary parent-absent families into sharper focus. The review highlights possibilities for fuller integration of these literatures, and emphasizes the clinical value of considering these types of experiences from a family and relational perspective, rather than an individual coping perspective. PMID:25304163

Double-difference Relocation of the Aftershocks of the Tecomán, Colima, Mexico Earthquake of 22 January 2003

NASA Astrophysics Data System (ADS)

Andrews, Vanessa; Stock, Joann; Ramírez Vázquez, Carlos Ariel; Reyes-Dávila, Gabriel

2011-08-01

On 22 January 2003, the M w = 7.6 Tecomán earthquake struck offshore of the state of Colima, Mexico, near the diffuse triple junction between the Cocos, Rivera, and North American plates. Three-hundred and fifty aftershocks of the Tecomán earthquake with magnitudes between 2.6 and 5.8, each recorded by at least 7 stations, are relocated using the double difference method. Initial locations are determined using P and S readings from the Red Sismológica Telemétrica del Estado de Colima (RESCO) and a 1-D velocity model. Because only eight RESCO stations were operating immediately following the Tecomán earthquake, uncertainties in the initial locations and depths are fairly large, with average uncertainties of 8.0 km in depth and 1.4 km in the north-south and east-west directions. Events occurring between 24 January and 31 January were located using not only RESCO phase readings but also additional P and S readings from 11 temporary stations. Average uncertainties decrease to 0.8 km in depth, 0.3 km in the east-west direction, and 0.7 km in the north-south direction for events occurring while the temporary stations were deployed. While some preliminary studies of the early aftershocks suggested that they were dominated by shallow events above the plate interface, our results place the majority of aftershocks along the plate interface, for a slab dipping between approximately 20° and 30°. This is consistent with the slab positions inferred from geodetic studies. We do see some upper plate aftershocks that may correspond to forearc fault zones, and faults inland in the upper plate, particularly among events occurring more than 3 months after the mainshock.

Location Capability and Site Characterization Installing a Borehole VBB Seismometer: the OGS Experience in Ferrara (Italy)

NASA Astrophysics Data System (ADS)

Pesaresi, D.; Barnaba, C.

2014-12-01

The Centro di Ricerche Sismologiche (CRS, Seismological Research Centre) of the Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS, Italian National Institute for Oceanography and Experimental Geophysics) in Udine (Italy) after the strong earthquake of magnitude M=6.4 occurred in 1976 in the Italian Friuli-Venezia Giulia region, started to operate the Northeastern Italy Seismic Network: it currently consists of 19 very sensitive broad band and 17 simpler short period seismic stations, all telemetered to and acquired in real time at the OGS CRS data centre in Udine. The southwestern edge of the OGS seismic network stands on the Po alluvial basin: earthquake localization and characterization in this area is affected by the presence of soft alluvial deposits. Following the ML=5.9 earthquake that struck the Emilia region around Ferrara in Northern Italy on May 20, 2012, a cooperation of Istituto Nazionale di Geofisica e Vulcanologia, OGS, the Comune di Ferrara and the University of Ferrara lead to the reinstallation of a previously existing very broad band (VBB) borehole seismic station in Ferrara and to the deployment of a temporary seismographic network consisting of eight portable seismological stations, to record the local earthquakes that occurred during the seismic sequence. The aim of the OGS intervention was on one hand to extend its real time seismic monitoring capabilities toward South-West, including Ferrara and its surroundings, and on the other hand to evaluate seismic site responses in the area. We will introduce details of the Ferrara VBB borehole station and the OGS temporary seismographic network configuration and installation. We will then illustrate the location capability performances, and finally we will shortly describe seismic site characterization with surface/borehole comparisons in terms of seismic noise, site amplification and resonance frequencies.

Correction of clock errors in seismic data using noise cross-correlations

NASA Astrophysics Data System (ADS)

Hable, Sarah; Sigloch, Karin; Barruol, Guilhem; Hadziioannou, Céline

2017-04-01

Correct and verifiable timing of seismic records is crucial for most seismological applications. For seismic land stations, frequent synchronization of the internal station clock with a GPS signal should ensure accurate timing, but loss of GPS synchronization is a common occurrence, especially for remote, temporary stations. In such cases, retrieval of clock timing has been a long-standing problem. The same timing problem applies to Ocean Bottom Seismometers (OBS), where no GPS signal can be received during deployment and only two GPS synchronizations can be attempted upon deployment and recovery. If successful, a skew correction is usually applied, where the final timing deviation is interpolated linearly across the entire operation period. If GPS synchronization upon recovery fails, then even this simple and unverified, first-order correction is not possible. In recent years, the usage of cross-correlation functions (CCFs) of ambient seismic noise has been demonstrated as a clock-correction method for certain network geometries. We demonstrate the great potential of this technique for island stations and OBS that were installed in the course of the Réunion Hotspot and Upper Mantle - Réunions Unterer Mantel (RHUM-RUM) project in the western Indian Ocean. Four stations on the island La Réunion were affected by clock errors of up to several minutes due to a missing GPS signal. CCFs are calculated for each day and compared with a reference cross-correlation function (RCF), which is usually the average of all CCFs. The clock error of each day is then determined from the measured shift between the daily CCFs and the RCF. To improve the accuracy of the method, CCFs are computed for several land stations and all three seismic components. Averaging over these station pairs and their 9 component pairs reduces the standard deviation of the clock errors by a factor of 4 (from 80 ms to 20 ms). This procedure permits a continuous monitoring of clock errors where small clock drifts (1 ms/day) as well as large clock jumps (6 min) are identified. The same method is applied to records of five OBS stations deployed within a radius of 150 km around La Réunion. The assumption of a linear clock drift is verified by correlating OBS for which GPS-based skew corrections were available with land stations. For two OBS stations without skew estimates, we find clock drifts of 0.9 ms/day and 0.4 ms/day. This study salvages expensive seismic records from remote regions that would be otherwise lost for seismicity or tomography studies.

Filling temporary underground structures and workings at high-head hydro developments

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

Ilyushin, V.F.

1994-12-01

Examples of backfilling temporary underground structures and workings at hydroelectric stations in Russia are cited. Structures backfilled include temporary tunnels and auxiliary workings (shafts, chambers, etc.). Detail drawings illustrate many of the examples. Examples of backfilling at a number of hydropower plants are given; however, the main emphasis is on construction of Nurek Hydroelectric Station. 8 refs., 11 figs.

Sensor emplacement testing at Poker Flat, Alaska

NASA Astrophysics Data System (ADS)

Reusch, A.; Beaudoin, B. C.; Anderson, K. E.; Azevedo, S.; Carothers, L.; Love, M.; Miller, P. E.; Parker, T.; Pfeifer, M.; Slad, G.; Thomas, D.; Aderhold, K.

2013-12-01

PASSCAL provides equipment and support for temporary seismic projects. Speed and efficiency of deployments are essential. A revised emplacement technique of putting broadband sensors directly into soil (aka direct burial) is being tested. The first phase (fall 2011 to spring 2013) comparing data quality and sensor stability between the direct burial and the traditional 1 m deep temporary PASSCAL-style vault in a wet and noisy site near San Antonio, NM is complete. Results suggest there is little or no difference in sensor performance in the relatively high-noise environment of this initial test. The second phase was started in November 2012 with the goal of making the same comparison, but at Poker Flat, Alaska, in a low-noise, high-signal, cold and wet environment, alongside a Transportable Array (TA) deployment to be used as a performance control. This location is in an accessible and secure area with very low site noise. In addition to benefiting future worldwide PASSCAL deployments, the Poker Flat experiment serves a secondary purpose of testing modifications necessary to successfully deploy and recover broadband stations in a cold environment with the limited logistics anticipated for remote Flexible Array (FA) and PASSCAL Program deployments in Alaska. Developing emplacement techniques that maintain high data quality and data return while minimizing logistics is critical to enable principle investigators to effectively and efficiently co-locate within the future TA Alaska footprint. Three Nanometrics sensors were installed in November 2012 in power-augered holes 76 cm in depth: a Trillium Compact Posthole (PH) and two Trillium 120PH units (one standard PH and one enhanced PHQ). The installations took less than 8 hours in -30°C conditions with 4 hours of usable daylight. The Compact PH and the 120PHQ are delivering data in realtime, while the 120PH is testing standalone power and data collection systems. Preliminary results compare favorably to each other as well as the nearby Trillium 240 in a traditional TA surface vault and a 120PH in a 5 m machine-drilled borehole. This summer, two Trillium 120PA sensors were installed at a depth of 54 cm in traditional PASSCAL-style vaults, adjacent to the Trillium Compact PH, Trillium 120PH and 120PHQ emplacements. Analysis of the data collected from these five sensors will include the use of probability density functions of power spectral density to examine temporal trends in noise, signal-to-noise ratios for local, regional, and teleseismic earthquakes, and coherence of both noise and earthquake signal recordings to compare the data quality of direct burial versus temporary PASSCAL-style vaults sensor emplacements.

Seismarmara 2001: A Marine Seismic Survey and Offshore-onshore Artificial Source and Natural Earthquakes In The Seismogenic Region of The Sea of Marmara

NASA Astrophysics Data System (ADS)

Hirn, A.; Singh, S.; Charvis, P.; Géli, L.; Laigle, M.; Lépine, J.-C.; de Voogd, B.; Saatcilar, R.; Taymaz, T.; Ozalaybey, S.; Shimamura, H.; Selvi, O.; Karabulut, H.; Murai, Y.; Nishimura, Y.; Yamada, A.; Vigner, A.; Bazin, S.; Tan, O.; Yolsal, S.; Aktar, M.; Galvé, A.; Sapin, M.; Marthelot, J.-M.; Imren, C.; Ergin, M.; Tapirdamaz, C.; Koçaoglu, A.; Tarancioglu, A.; Diaz, J.; Verhille, J.; Auffret, Y.; Cetin, S.; Oçakoglu, N.; Karakoç, F.; Klien, E.; Ricolleau, A.; Selvigen, V.; Demirbag, E.; Hakyemez, Y.; Sarikawak, K.

SEISMARMARA is a Turkish-French survey carried out in July-October 2001 as a multi-method approach of seismic structure and activity of the Sea of Marmara. This is the segment of the North Anatolian Fault system that continues the one that produced the two destructive earthquakes in 1999 to the East, and is prone to future major earth- quakes as it has experienced in the past. Aims of the programme are to shed light on the regional tectonics and recent evolution at crustal scale, image faults by their structure and seismic activity, and provide a model and reference to improve loca- tion of earthquakes and focal mechanism studies. The programme bases on marine multichannel reflection seismics (MCS), ocean bottom seismometers (OBS) and land stations recording of wide-angle reflection-refraction from the same source, as well as recording of local earthquakes for tomography and stress/strain distribution. The French N/O Le Nadir acquired 4000 km of MCS profiles in the northern Sea of Mar- mara, using a 4.5 km long digital streamer with 360-channels and sources of 8100 cu. in., or 2900 cu. in., provided by a 12-airgun array in single-bubble mode. Navigation safety was provided by a vessel of the Turkish Coast Guards (Sahil Güvenlik), Leg 1 comprises 4 E-W lines and 30 cross-lines in the whole Marmara Trough, leg 2 has 1 been devoted to a very dense grid of lines in the Cinarcik basin and its margins, record- ing over 80 dip-lines at 0.6-0.9 km spacing At sea-bottom 38 OBS, with 3-component sensors and continuous recording over 1 to 2-month in order to also record natural earthquakes were deployed and collected by the Turkish ship MTA Sismik-1. On land the permanent array has been complemented by as many temporary stations, in par- ticular over 30 continuous recording 3-component 2 Hz stations. Refraction seismics from offshore to onshore was further implemented by short-duration deployments of vertical component lightweight instruments with short recording capacity. A teleseis- mic recording effort with temporary stations, tested in the previous year concentrated on a line through the NAF East of Izmit 2

Passive Seismic Experiment to understand the basement and crustal structure, Northern Red Sea

NASA Astrophysics Data System (ADS)

Sinadinovski, Cvetan; Aldamegh, Khalid; Ball, Philip; Janoubi, Emad; Afifi, AbdulKader; Ion, Dumitru; Nayak, Goutam; Borsato, Ron

2017-04-01

In 2011, air gun seismic surveys were performed in the Red Sea in conjunction with an offshore survey where portable seismic stations were deployed onshore up to 250 km inland from the shoreline. In total, 30 temporary broadband stations were deployed in the northern Red Sea. The recorded shot data were analyzed in conjunction with earthquake records that occurred during the three-month deployment period. The receiver function data were modeled using an advanced 3D modeling software. Gravity data were modeled as well on five regional profiles to provide additional constraints for the depth-to-basement and depth-to-Moho discontinuity. The passive (earthquakes) and active (air gun) data for both areas were modeled separately and then in a joint scheme. This experiment was unique, where no previous deployment at this scale had been attempted before in Saudi Arabia. The tomography results provide for the first time a detailed insight of the deeper crustal structure in the Red Sea margin. The results reveal a complex geology with a heterogeneous crust and upper mantle. The crustal-mantle discontinuity was picked assuming a Vp velocity of around 8.0 km/s. The Moho discontinuity offshore appears to vary in depth from 17 km to 27 km, increasing to 22 km to 35 km onshore. The average crustal thickness inland is 28 km, whereas the average thickness offshore is 22 km. These 3D images of the Moho show that thinning of the crust was not just coast-parallel as proposed from previous 2D or 1D studies. Such findings can help in better understanding of the rift related processes in the Red Sea

Monitoring storm tide and flooding from Hurricane Matthew along the Atlantic coast of the United States, October 2016

USGS Publications Warehouse

Frantz, Eric R.; Byrne,, Michael L.; Caldwell, Andral W.; Harden, Stephen L.

2017-11-02

IntroductionHurricane Matthew moved adjacent to the coasts of Florida, Georgia, South Carolina, and North Carolina. The hurricane made landfall once near McClellanville, South Carolina, on October 8, 2016, as a Category 1 hurricane on the Saffir-Simpson Hurricane Wind Scale. The U.S. Geological Survey (USGS) deployed a temporary monitoring network of storm-tide sensors at 284 sites along the Atlantic coast from Florida to North Carolina to record the timing, areal extent, and magnitude of hurricane storm tide and coastal flooding generated by Hurricane Matthew. Storm tide, as defined by the National Oceanic and Atmospheric Administration, is the water-level rise generated by a combination of storm surge and astronomical tide during a coastal storm.The deployment for Hurricane Matthew was the largest deployment of storm-tide sensors in USGS history and was completed as part of a coordinated Federal emergency response as outlined by the Stafford Act (Public Law 92–288, 42 U.S.C. 5121–5207) under a directed mission assignment by the Federal Emergency Management Agency. In total, 543 high-water marks (HWMs) also were collected after Hurricane Matthew, and this was the second largest HWM recovery effort in USGS history after Hurricane Sandy in 2012.During the hurricane, real-time water-level data collected at temporary rapid deployment gages (RDGs) and long-term USGS streamgage stations were relayed immediately for display on the USGS Flood Event Viewer (https://stn.wim.usgs.gov/FEV/#MatthewOctober2016). These data provided emergency managers and responders with critical information for tracking flood-effected areas and directing assistance to effected communities. Data collected from this hurricane can be used to calibrate and evaluate the performance of storm-tide models for maximum and incremental water level and flood extent, and the site-specific effects of storm tide on natural and anthropogenic features of the environment.

BARENTS16: a 1-D velocity model for the western Barents Sea

NASA Astrophysics Data System (ADS)

Pirli, Myrto; Schweitzer, Johannes

2018-01-01

A minimum 1-D seismic velocity model for routine seismic event location purposes was determined for the area of the western Barents Sea, using a modified version of the VELEST code. The resulting model, BARENTS16, and corresponding station corrections were produced using data from stations at regional distances, the vast majority located in the periphery of the recorded seismic activity, due to the unfavorable land-sea distribution. Recorded seismicity is approached through the listings of a joint bulletin, resulting from the merging of several international and regional bulletins for the region, as well as additional parametric data from temporary deployments. We discuss the challenges posed by this extreme network-seismicity geometry in terms of velocity estimation resolution and result stability. Although the conditions do not facilitate the estimation of meaningful station corrections at the farthermost stations, and even well-resolved corrections do not have a convincing contribution, we show that the process can still converge to a stable velocity average for the crust and upper mantle, in good agreement with a priori information about the regional structure and geology, which reduces adequately errors in event location estimates.

47 CFR 22.1031 - Temporary fixed stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

....1031 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Offshore Radiotelephone Service § 22.1031 Temporary fixed stations. The FCC may, upon... days before the end of the six month period. (b) International communications. Communications between...

Developing a robust wireless sensor network structure for environmental sensing

NASA Astrophysics Data System (ADS)

Zhang, Z.; Oroza, C.; Glaser, S. D.; Bales, R. C.; Conklin, M. H.

2013-12-01

The American River Hydrologic Observatory is being strategically deployed as a real-time ground-based measurement network that delivers accurate and timely information on snow conditions and other hydrologic attributes with a previously unheard of granularity of time and space. The basin-scale network involves 18 sub-networks set out at physiographically representative locations spanning the seasonally snow-covered half of the 5000 km2 American river basin. Each sub-network, covering about a 1-km2 area, consists of 10 wirelessly networked sensing nodes that continuously measure and telemeter temperature, and snow depth; plus selected locations are equipped with sensors for relative humidity, solar radiation, and soil moisture at several depths. The sensor locations were chosen to maximize the variance sampled for snow depth within the basin. Network design and deployment involves an iterative but efficient process. After sensor-station locations are determined, a robust network of interlinking sensor stations and signal repeaters must be constructed to route sensor data to a central base station with a two-way communicable data uplink. Data can then be uploaded from site to remote servers in real time through satellite and cell modems. Signal repeaters are placed for robustness of a self-healing network with redundant signal paths to the base station. Manual, trial-and-error heuristic approaches for node placement are inefficient and labor intensive. In that approach field personnel must restructure the network in real time and wait for new network statistics to be calculated at the base station before finalizing a placement, acting without knowledge of the global topography or overall network structure. We show how digital elevation plus high-definition aerial photographs to give foliage coverage can optimize planning of signal repeater placements and guarantee a robust network structure prior to the physical deployment. We can also 'stress test' the final network by simulating the failure of an individual node and investigating the effect and the self-healing ability of the stressed network. The resulting sensor network can survive temporary service interruption from a small subset of signal repeaters and sensor stations. The robustness and the resilient of the network performance ensure the integrity of the dataset and the real-time transmissibility during harsh conditions.

47 CFR 101.817 - Notification of station operation at temporary locations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Notification of station operation at temporary locations. 101.817 Section 101.817 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.817...

47 CFR 101.817 - Notification of station operation at temporary locations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Notification of station operation at temporary locations. 101.817 Section 101.817 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.817...

47 CFR 101.817 - Notification of station operation at temporary locations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Notification of station operation at temporary locations. 101.817 Section 101.817 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.817...

47 CFR 101.817 - Notification of station operation at temporary locations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Notification of station operation at temporary locations. 101.817 Section 101.817 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.817...

47 CFR 101.817 - Notification of station operation at temporary locations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Notification of station operation at temporary locations. 101.817 Section 101.817 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Local Television Transmission Service § 101.817...

Complicated seismic anisotropy beneath south-central Mongolia and its geodynamic implications

NASA Astrophysics Data System (ADS)

Qiang, Zhengyang; Wu, Qingju; Li, Yonghua; Gao, Mengtan; Demberel, Sodnomsambuu; Ulzibat, Munkhuu; Sukhbaatar, Usnikh; Flesch, Lucy M.

2017-05-01

Two years of high-quality broadband seismic data from 69 temporary stations deployed in south-central Mongolia provide an opportunity to study the anisotropy-forming mechanisms in this area. The majority of shear wave splitting observations determined from the analysis of teleseismic SKS phase are characterized by NW-SE trending fast directions with large splitting delay times (greater than 2.0 s at six stations), which is inferred to be generated by active asthenospheric flow. The variation of the fast direction may be associated with deflection of asthenosphere around the deep Siberian cratonic keel at the base of the lithosphere. Several of the NE-SW trending fast directions with relatively small delay times observed in the Gobi Desert are parallel to the strike of the main faults and sutures, which may represent lithospheric deformation. In addition, it is inferred that small-scale hot mantle upwelling is responsible for generating a cluster of null measurements observed on the south of the Hentiy Mountain.

Identifying bubble collapse in a hydrothermal system using hidden Markov models

USGS Publications Warehouse

Dawson, P.B.; Benitez, M.C.; Lowenstern, J. B.; Chouet, B.A.

2012-01-01

Beginning in July 2003 and lasting through September 2003, the Norris Geyser Basin in Yellowstone National Park exhibited an unusual increase in ground temperature and hydrothermal activity. Using hidden Markov model theory, we identify over five million high-frequency (>15Hz) seismic events observed at a temporary seismic station deployed in the basin in response to the increase in hydrothermal activity. The source of these seismic events is constrained to within ???100 m of the station, and produced ???3500-5500 events per hour with mean durations of ???0.35-0.45s. The seismic event rate, air temperature, hydrologic temperatures, and surficial water flow of the geyser basin exhibited a marked diurnal pattern that was closely associated with solar thermal radiance. We interpret the source of the seismicity to be due to the collapse of small steam bubbles in the hydrothermal system, with the rate of collapse being controlled by surficial temperatures and daytime evaporation rates. copyright 2012 by the American Geophysical Union.

Identifying bubble collapse in a hydrothermal system using hiddden Markov models

USGS Publications Warehouse

Dawson, Phillip B.; Benitez, M.C.; Lowenstern, Jacob B.; Chouet, Bernard A.

2012-01-01

Beginning in July 2003 and lasting through September 2003, the Norris Geyser Basin in Yellowstone National Park exhibited an unusual increase in ground temperature and hydrothermal activity. Using hidden Markov model theory, we identify over five million high-frequency (>15 Hz) seismic events observed at a temporary seismic station deployed in the basin in response to the increase in hydrothermal activity. The source of these seismic events is constrained to within ~100 m of the station, and produced ~3500–5500 events per hour with mean durations of ~0.35–0.45 s. The seismic event rate, air temperature, hydrologic temperatures, and surficial water flow of the geyser basin exhibited a marked diurnal pattern that was closely associated with solar thermal radiance. We interpret the source of the seismicity to be due to the collapse of small steam bubbles in the hydrothermal system, with the rate of collapse being controlled by surficial temperatures and daytime evaporation rates.

Site response in the eastern United States: A comparison of Vs30 measurements with estimates from horizontal:vertical spectral ratios

USGS Publications Warehouse

McNamara, Daniel E.; Stephenson, William J.; Odum, Jackson K.; Williams, Robert; Gee, Lind

2014-01-01

Earthquake damage is often increased due to local ground-motion amplification caused by soft soils, thick basin sediments, topographic effects, and liquefaction. A critical factor contributing to the assessment of seismic hazard is detailed information on local site response. In order to address and quantify the site response at seismograph stations in the eastern United States, we investigate the regional spatial variation of horizontal:vertical spectral ratios (HVSR) using ambient noise recorded at permanent regional and national network stations as well as temporary seismic stations deployed in order to record aftershocks of the 2011 Mineral, Virginia, earthquake. We compare the HVSR peak frequency to surface measurements of the shear-wave seismic velocity to 30 m depth (Vs30) at 21 seismograph stations in the eastern United States and find that HVSR peak frequency increases with increasing Vs30. We use this relationship to estimate the National Earthquake Hazards Reduction Program soil class at 218 ANSS (Advanced National Seismic System), GSN (Global Seismographic Network), and RSN (Regional Seismograph Networks) locations in the eastern United States, and suggest that this seismic station–based HVSR proxy could potentially be used to calibrate other site response characterization methods commonly used to estimate shaking hazard.

Deployment Efficiency and Barrier Effectiveness Testing of a Temporary Anti-Personnel (TAP) Barrier System.

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

Allen, David James; Hedrick, Charles D.; Martinez, Ruben

This report documents tests conducted by Sandia National Laboratories (SNL) on behalf of the U.S. Department of State to evaluate a temporary anti-personnel (TAP) barrier system developed by Mitigation Technologies. For this, the SNL Denial and Structural Assessment department developed a test protocol for the evaluation of the TAP barrier system on the basis of deployment efficiency and barrier effectiveness against a riotous/mob attack threat. The test protocol was then executed by SNL personnel and the results of the testing are documented.

Regional crustal structures along several paths in India and its surrounding regions using local P- and S-wave travel times and regional waveforms recorded from the March 28, 1999 Chamoli earthquake sequence

NASA Astrophysics Data System (ADS)

Saikia, C. K.; Ichinose, G. A.; Kayal, J. R.; Bhattacharya, S. N.; Shukla, A. K.

2001-12-01

The March 28, 1999 Chamoli earthquake (Mw 6.8) in northwest India generated a large sequence of aftershocks (M_ w> 4.0) which were recorded by a temporary network ofshort-period stations deployed by various organizations, namely India Meteorological Department (IMD), Geological Survey of India (GSI), National Geophysical Research Institute (NGRI) and Wadia Institute of Himalayan Geology (WIHG) in India. We inverted the local P- and S-wave arrival times from about 20 local stations jointly for all available aftershocks implementing a technique which optimizes both earthquake locations and crustal velocity model. Of these, seven events were recorded by more than 5 stations locating within 5o of the epicenters withazimuthal gap not greater than 90o. We used these events to compute the station correctionsfor local stations and applied these station corrections to relocate the entire sequence of the Chamoli aftershocks. The relocation vectors which indicate the direction toward which the events would move from the reference locations (in this case the GSI locations) suggest that for the majority of the seismic events they show movement towards the epicentral locations of the mainshock. The new locations of these events also show improvements in the error ellipse measurements. We have also investigated variations in crustal models using regional broadband seismograms from the mainshock recorded by the IMD stations in India (IMD, 2000). Using a crustal model developed earlier by Bhattacharya using surface-wave dispersion for northern India as a starting model, we conducted a systematic analysis of surface-wave dispersion characteristics recorded at these broadband stations. We synthesized f-k seismograms andexamined the relative amplitude of the Pnl waves to the surface waves and their absolutetravel-time differences. We used focal mechanism and depth that were independently determined by modeling teleseismic depth phases, pP and sP, and by modeling regional seismograms recorded by broadband stations of a temporary network of the INDEPTH experiment operated in China near the station LSA. This investigation suggests that data along different paths toward the Indian subcontinent require different thicknesses for the crustal structure to account for varying thicknesses of the sediment of the Gangetic basin. We are currently examining the surface-wave dispersions recorded by stations of the INDEPTH experiment and at HYB in India. We will present results from investigations of these broadband seismograms and comparison of these results with those determined earlier by various investigators using the limited WWSSN seismograms.

47 CFR 101.209 - Operation of stations at temporary fixed locations for communication between the United States...

Code of Federal Regulations, 2010 CFR

2010-10-01

... locations for communication between the United States and Canada or Mexico. 101.209 Section 101.209... communication between the United States and Canada or Mexico. Stations authorized to operate at temporary fixed... Mexico, without prior specific notification to, and authorization from, the Commission. Notification of...

47 CFR 101.209 - Operation of stations at temporary fixed locations for communication between the United States...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Operation of stations at temporary fixed locations for communication between the United States and Canada or Mexico. 101.209 Section 101.209 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE...

47 CFR 101.209 - Operation of stations at temporary fixed locations for communication between the United States...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Operation of stations at temporary fixed locations for communication between the United States and Canada or Mexico. 101.209 Section 101.209 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE...

47 CFR 101.209 - Operation of stations at temporary fixed locations for communication between the United States...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Operation of stations at temporary fixed locations for communication between the United States and Canada or Mexico. 101.209 Section 101.209 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE...

47 CFR 101.209 - Operation of stations at temporary fixed locations for communication between the United States...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Operation of stations at temporary fixed locations for communication between the United States and Canada or Mexico. 101.209 Section 101.209 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES FIXED MICROWAVE...

Monitoring the Transport of Sediment During Tropical Cyclones From High-frequency Seismic Noise in Two Rivers of La Réunion Island

NASA Astrophysics Data System (ADS)

Fontaine, F. R.; Gonzalez, A.; Burtin, A.; Barruol, G.; Recking, A.; Join, J. L.; Delcher, E.

2016-12-01

La Réunion Island is a basaltic shield volcano located in the western Indian Ocean. The island undergoes heavy annual precipitations during tropical depressions and cyclones. These rainfalls modify the stream dynamics and sediment transport of rivers. The transport of sediment participates to the erosion of the volcanic island, however, in situ characterization is difficult during high water stage. In the frame of the Rivière des Pluies project, we are deploying a temporary seismic network of 10 three-component broadband seismometers around two rivers: Rivière des Pluies and Rivière du Mât. The goal of the project is to monitor spatial and temporal variations of the river's bed-load during tropical cyclones with high-frequency noise. Meteorological and hydrological stations are installed at both rivers providing valuable data such as precipitations, water discharge and water level. We will also sample the bed surface grain size distribution by visual count to determine its influence on the seismic noise. We present preliminary results from two broadband seismic stations located near instrumented streams. SALA station from the temporary RHUM-RUM seismic network (http://www.rhum-rum.net/en/) was installed close to the Rivière du Mât and the permanent GEOSCOPE RER station is located close to the Rivière de l'Est. We analyzed the footprint of the cyclone Bejisa in January 2014. We observe a significant increase of the precipitation when the cyclone eye is 300 km close to the island followed by the increase of the water discharge. Simultaneously the seismic signal shows a sudden increase of the power spectral density visible above 1 Hz. Further investigations on the relationship between the seismic noise and the hydrological and meteorological parameters will help us quantifying the river bed-load.

Investigating subduction reversal in Papua New Guinea from automatic analysis of seismicity recorded on a temporary local network

NASA Astrophysics Data System (ADS)

Hicks, S. P.; Harmon, N.; Rychert, C.; Tharimena, S.; Bogiatzis, P.; Savage, B.; Shen, Y.; Baillard, C.

2017-12-01

The area of Papua New Guinea is one of the most seismically active regions on the planet. Seismicity in the region results from oblique convergence between the Pacific and India-Australia plates, with deformation occurring across a broad region involving several microplates. The region gives an excellent natural laboratory to test geodynamic models of subduction polarity reversal, microplate interaction, and to delineate the structure of subducting plates and relic structures at depth. However, a lack of permanent seismic stations means that routine earthquake locations for small to intermediate sized earthquakes have significant location errors. In 2014, we deployed a temporary network of eight broadband stations on islands in eastern Papua New Guinea to record ongoing seismic deformation. The network straddles a complex region where subduction of the Solomon plate occurs to the south and possible subduction of the Ontong-Java plateau occurs to the north. The stations were installed for 27 months. During the deployment period, there were 13 M>6.5 earthquakes in the area, including M7.5 doublet events in 2015, giving a rich seismic dataset. A high-quality catalogue of local events was formed by a multi-step process. Using the scanloc module of SeisComp3, we first detect P-onsets using a STA/LTA detection. Once clusters of P onsets are found, S-wave picks are incorporated based on a pre-defined window length of maximum S-P time. Groups of onsets are then associated to events, giving us a starting catalogue of 269 events (1765 P-onsets) with minimum magnitude of M 3.5. In a second step, we refine onset times using a Kurtosis picker to improve location accuracy. To form robust hypocentral locations using an appropriate structural model for the area and to constrain crust and mantle structure in the region, we derive a minimum 1-D velocity model using the VELEST program. We use a starting model from Abers et al. (1991) and we restrict our catalogue to events with an azimuthal gap of <270°, leaving 147 well-located events. This new seismic catalogue gives a detailed insight into the plate boundary structures at depth in the Papua New Guinea region. We are also able to delineate Wadati-Benioff seismicity to 600 km depth in the subducting Solomon Sea plate beneath the New Britain arc.

Investigating subduction reversal in Papua New Guinea from automatic analysis of seismicity recorded on a temporary local network

NASA Astrophysics Data System (ADS)

Hicks, S. P.; Harmon, N.; Rychert, C.; Tharimena, S.; Bogiatzis, P.; Savage, B.; Shen, Y.; Baillard, C.

2016-12-01

The area of Papua New Guinea is one of the most seismically active regions on the planet. Seismicity in the region results from oblique convergence between the Pacific and India-Australia plates, with deformation occurring across a broad region involving several microplates. The region gives an excellent natural laboratory to test geodynamic models of subduction polarity reversal, microplate interaction, and to delineate the structure of subducting plates and relic structures at depth. However, a lack of permanent seismic stations means that routine earthquake locations for small to intermediate sized earthquakes have significant location errors. In 2014, we deployed a temporary network of eight broadband stations on islands in eastern Papua New Guinea to record ongoing seismic deformation. The network straddles a complex region where subduction of the Solomon plate occurs to the south and possible subduction of the Ontong-Java plateau occurs to the north. The stations were installed for 27 months. During the deployment period, there were 13 M>6.5 earthquakes in the area, including M7.5 doublet events in 2015, giving a rich seismic dataset. A high-quality catalogue of local events was formed by a multi-step process. Using the scanloc module of SeisComp3, we first detect P-onsets using a STA/LTA detection. Once clusters of P onsets are found, S-wave picks are incorporated based on a pre-defined window length of maximum S-P time. Groups of onsets are then associated to events, giving us a starting catalogue of 269 events (1765 P-onsets) with minimum magnitude of M 3.5. In a second step, we refine onset times using a Kurtosis picker to improve location accuracy. To form robust hypocentral locations using an appropriate structural model for the area and to constrain crust and mantle structure in the region, we derive a minimum 1-D velocity model using the VELEST program. We use a starting model from Abers et al. (1991) and we restrict our catalogue to events with an azimuthal gap of <270°, leaving 147 well-located events. This new seismic catalogue gives a detailed insight into the plate boundary structures at depth in the Papua New Guinea region. We are also able to delineate Wadati-Benioff seismicity to 600 km depth in the subducting Solomon Sea plate beneath the New Britain arc.

UMTS rapid response real-time seismic networks: implementation and strategies at INGV

NASA Astrophysics Data System (ADS)

Govoni, A.; Margheriti, L.; Moretti, M.; Lauciani, V.; Sensale, G.; Bucci, A.; Criscuoli, F.

2015-12-01

Universal Mobile Telecommunications System (UMTS) and its evolutions are nowadays the most affordable and widespread data communication infrastructure available almost world wide. Moreover the always growing cellular phone market is pushing the development of new devices with higher performances and lower power consumption. All these characteristics make UMTS really useful for the implementation of an "easy to deploy" temporary real-time seismic station. Despite these remarkable features, there are many drawbacks that must be properly taken in account to effectively transmit the seismic data: Internet security, signal and service availability, power consumption. - Internet security: exposing seismological data services and seismic stations to the Internet is dangerous, attack prone and can lead to downtimes in the services, so we setup a dedicated Virtual Private Network (VPN) service to protect all the connected devices. - Signal and service availability: while for temporary experiment a carefull planning and an accurate site selection can minimize the problem, this is not always the case with rapid response networks. Moreover, as with any other leased line, the availability of the UMTS service during a seismic crisis is basically unpredictable. Nowadays in Italy during a major national emergency a Committee of the Italian Civil Defense ensures unified management and coordination of emergency activities. Inside it the telecom companies are committed to give support to the crisis management improving the standards in their communication networks. - Power consumption: it is at least of the order of that of the seismic station and, being related to data flow and signal quality is largely unpredictable. While the most secure option consists in adding a second independent solar power supply to the seismic station, this is not always a very convenient solution since it doubles the cost and doubles the equipment on site. We found that an acceptable trade-off is to add an inexpensive Low Voltage Disconnect (LVD) circuit to the UMTS router power supply that switches off the data transmission when the power is low. This greatly reduces the probability of data loss but lowers the real-time data availabilty. This approach guarantees on the average a satisfactory data acquistion rate, only in very few cases and when the real-time data is extremely important for a particular site we needed to double the power supply on the site. Overall the UMTS data transmission has been used in most temporary seismic experiments and in all seismic emergencies happened in Italy since 2010 and has proved to be a very cost effective approach with real-time data acquisition rates usually greater than 97 % and all the benefits that result from the fast integration of the temporary data in the National Network monitoring system and in the EIDA data bank.

StackSplit - a plugin for multi-event shear wave splitting analyses in SplitLab

NASA Astrophysics Data System (ADS)

Grund, Michael

2017-08-01

SplitLab is a powerful and widely used tool for analysing seismological shear wave splitting of single event measurements. However, in many cases, especially temporary station deployments close to the noisy seaside, ocean bottom or for recordings affected by strong anthropogenic noise, only multi-event approaches provide stable and reliable splitting results. In order to extend the original SplitLab environment for such analyses, I present the StackSplit plugin that can easily be implemented within the well accepted main program. StackSplit grants easy access to several different analysis approaches within SplitLab, including a new multiple waveform based inversion method as well as the most established standard stacking procedures. The possibility to switch between different analysis approaches at any time allows the user for the most flexible processing of individual multi-event splitting measurements for a single recording station. Besides the provided functions of the plugin, no other external program is needed for the multi-event analyses since StackSplit performs within the available SplitLab structure which is based on MATLAB. The effectiveness and use of this plugin is demonstrated with data examples of a long running seismological recording station in Finland.

Moho map of South America from receiver functions and surface waves

NASA Astrophysics Data System (ADS)

Lloyd, Simon; van der Lee, Suzan; FrançA, George Sand; AssumpçãO, Marcelo; Feng, Mei

2010-11-01

We estimate crustal structure and thickness of South America north of roughly 40°S. To this end, we analyzed receiver functions from 20 relatively new temporary broadband seismic stations deployed across eastern Brazil. In the analysis we include teleseismic and some regional events, particularly for stations that recorded few suitable earthquakes. We first estimate crustal thickness and average Poisson's ratio using two different stacking methods. We then combine the new crustal constraints with results from previous receiver function studies. To interpolate the crustal thickness between the station locations, we jointly invert these Moho point constraints, Rayleigh wave group velocities, and regional S and Rayleigh waveforms for a continuous map of Moho depth. The new tomographic Moho map suggests that Moho depth and Moho relief vary slightly with age within the Precambrian crust. Whether or not a positive correlation between crustal thickness and geologic age is derived from the pre-interpolation point constraints depends strongly on the selected subset of receiver functions. This implies that using only pre-interpolation point constraints (receiver functions) inadequately samples the spatial variation in geologic age. The new Moho map also reveals an anomalously deep Moho beneath the oldest core of the Amazonian Craton.

Estimating seismic site response in Christchurch City (New Zealand) from dense low-cost aftershock arrays

USGS Publications Warehouse

Kaiser, Anna E.; Benites, Rafael A.; Chung, Angela I.; Haines, A. John; Cochran, Elizabeth S.; Fry, Bill

2011-01-01

The Mw 7.1 September 2010 Darfield earthquake, New Zealand, produced widespread damage and liquefaction ~40 km from the epicentre in Christchurch city. It was followed by the even more destructive Mw 6.2 February 2011 Christchurch aftershock directly beneath the city’s southern suburbs. Seismic data recorded during the two large events suggest that site effects contributed to the variations in ground motion observed throughout Christchurch city. We use densely-spaced aftershock recordings of the Darfield earthquake to investigate variations in local seismic site response within the Christchurch urban area. Following the Darfield main shock we deployed a temporary array of ~180 low-cost 14-bit MEMS accelerometers linked to the global Quake-Catcher Network (QCN). These instruments provided dense station coverage (spacing ~2 km) to complement existing New Zealand national network strong motion stations (GeoNet) within Christchurch city. Well-constrained standard spectral ratios were derived for GeoNet stations using a reference station on Miocene basalt rock in the south of the city. For noisier QCN stations, the method was adapted to find a maximum likelihood estimate of spectral ratio amplitude taking into account the variance of noise at the respective stations. Spectral ratios for QCN stations are similar to nearby GeoNet stations when the maximum likelihood method is used. Our study suggests dense low-cost accelerometer aftershock arrays can provide useful information on local-scale ground motion properties for use in microzonation. Preliminary results indicate higher amplifications north of the city centre and strong high-frequency amplification in the small, shallower basin of Heathcote Valley.

47 CFR 1.931 - Application for special temporary authority.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Grants by Random Selection Wireless Radio Services Applications and Proceedings Application Requirements and Procedures § 1.931 Application for special temporary authority. (a) Wireless Telecommunications Services. (1) In circumstances requiring immediate or temporary use of station in the Wireless...

47 CFR 1.931 - Application for special temporary authority.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Grants by Random Selection Wireless Radio Services Applications and Proceedings Application Requirements and Procedures § 1.931 Application for special temporary authority. (a) Wireless Telecommunications Services. (1) In circumstances requiring immediate or temporary use of station in the Wireless...

47 CFR 1.931 - Application for special temporary authority.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Grants by Random Selection Wireless Radio Services Applications and Proceedings Application Requirements and Procedures § 1.931 Application for special temporary authority. (a) Wireless Telecommunications Services. (1) In circumstances requiring immediate or temporary use of station in the Wireless...

47 CFR 1.931 - Application for special temporary authority.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Wireless Radio Services Applications and Proceedings Application Requirements and Procedures § 1.931 Application for special temporary authority. (a) Wireless Telecommunications Services. (1) In circumstances requiring immediate or temporary use of station in the Wireless Telecommunications Services, carriers may...

47 CFR 1.931 - Application for special temporary authority.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Wireless Radio Services Applications and Proceedings Application Requirements and Procedures § 1.931 Application for special temporary authority. (a) Wireless Telecommunications Services. (1) In circumstances requiring immediate or temporary use of station in the Wireless Telecommunications Services, carriers may...

47 CFR 90.137 - Applications for operation at temporary locations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... evidence of frequency coordination. (b) When any unit or units of a base station or fixed station which are... Applications for operation at temporary locations. (a) An application for authority to operate a base or a... the following: (1) When one or more individual transmitters are to be operated by a licensee as a base...

Seismic Waveform Modeling of Broadband Data From a Temporary High-Density Deployment in the Los Angeles Basin

NASA Astrophysics Data System (ADS)

Herrman, M.; Polet, J.

2016-12-01

A total of 73 broadband seismometers were deployed for a passive source seismic experiment called the Los Angeles Syncline Seismic Interferometry Experiment (LASSIE) from September to November of 2014. The purpose of this experiment was to collect high density seismic data for the Los Angeles Basin (LAB) to better understand basin structure and response. This research will use the data collected from LASSIE to assess and refine current velocity models of the LAB using a full waveform modeling approach. To this end we will compare seismograms recorded by LASSIE for a subset of the 53 earthquakes and quarry blasts located by the Southern California Seismic Network (SCSN) that occurred within or near the LAB during the deployment period to synthetic seismograms generated by the Frequency-Wavenumber (FK) code developed by Zhu and Rivera (2002). A first analysis of the data indicates that roughly 25 of the 53 events have waveforms with sufficiently high signal to noise ratio, providing approximately 500 seismograms that are of suitable quality for comparison. We observe significant changes in waveform characteristics between stations with a very small separation distance of approximately 1 km. Focal mechanisms for most of these events have been obtained from Dr. Egill Hauksson (personal communication). We will show comparisons between the broadband velocity waveforms recorded by stations across the LASSIE array and FK synthetics determined for a variety of 1D velocity models that have been developed for the LAB area (such as Hadley and Kanamori, 1977; Hauksson, 1989, 1995 and Magistrale, 1992). The results of these comparisons will be analyzed to provide additional constraints on the subsurface seismic velocity structure within the Los Angeles basin.

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 5 2014-10-01 2014-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 5 2011-10-01 2011-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 5 2012-10-01 2012-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

47 CFR 101.125 - Temporary fixed antenna height restrictions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 5 2013-10-01 2013-10-01 false Temporary fixed antenna height restrictions... SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES Technical Standards § 101.125 Temporary fixed antenna height restrictions. The overall antenna structure heights employed by mobile stations in the Local...

Lithospheric Structure and Seismotectonics of Central East Antarctica

NASA Astrophysics Data System (ADS)

Reading, A. M.

2006-12-01

The lithosphere of central East Antarctica, the sector of the continent between 30°E - 120°E, is investigated using seismic methods including receiver function and shear-wave splitting analysis. Data from the broadband stations of the temporary SSCUA deployment (in the continental interior) are used together with records from the permanent GSN stations (on the coast) to carry out the first studies of crustal depth and structure, and patterns of seismic anisotropy across this region. The depth of the Moho is found to be 42 km (+/- 2 km) beneath Mawson station with similar structures extending southward across the Rayner province as far south as Beaver Lake. The Fisher Terrane is characterised by a crustal shear wavespeed profile showing few discontinuties with the Moho at a similar depth to the Rayner. South of Fisher, the crust becomes much shallower, with the Moho at 32 km depth. This shallow crust extends across the Lambert glacier to the Prydz coast and the Lambert Terrane. The characteristic crustal wavespeed profiles provide baseline structure for mapping the extent of the terrance beneath the Antarctic Ice Sheet in future deployments. Observations of seismic anisotropy are less well- defined but, at a reconnaissance level, show fast directions parallel to the present day coastline. This may be controlled by rift-related influences on the lithosphere associated with the breakup of East Gondwana. The seismicity is confirmed to be extremely low. The only seismogenic forces on the Antarctic plate in this region are acting at the boundary between the continental and oceanic lithosphere west of 50°E and east of 100°E and represent a superposition of tectonic and glaciogenic controls. The Lambert Glacier region shows little or no seismotectonic activity in the continental interior or on the oceanic margin.

Infrasound and Seismic Recordings of Rocket Launches from Kennedy Space Center, 2016-2017

NASA Astrophysics Data System (ADS)

McNutt, S. R.; Thompson, G.; Brown, R. G.; Braunmiller, J.; Farrell, A. K.; Mehta, C.

2017-12-01

We installed a temporary 3-station seismic-infrasound network at Kennedy Space Center (KSC) in February 2016 to test sensor calibrations and train students in field deployment and data acquisitions techniques. Each station featured a single broadband 3-component seismometer and a 3-element infrasound array. In May 2016 the network was scaled back to a single station due to other projects competing for equipment. To date 8 rocket launches have been recorded by the infrasound array, as well as 2 static tests, 1 aborted launch and 1 rocket explosion (see next abstract). Of the rocket launches recorded 4 were SpaceX Falcon-9, 2 were ULA Atlas-5 and 2 were ULA Delta-IV. A question we attempt to answer is whether the rocket engine type and launch trajectory can be estimated with appropriate travel-time, amplitude-ratio and spectral techniques. For example, there is a clear Doppler shift in seismic and infrasound spectrograms from all launches, with lower frequencies occurring later in the recorded signal as the rocket accelerates away from the array. Another question of interest is whether there are relationships between jet noise frequency, thrust and/or nozzle velocity. Infrasound data may help answer these questions. We are now in the process of deploying a permanent seismic and infrasound array at the Astronaut Beach House. 10 more rocket launches are schedule before AGU. NASA is also conducting a series of 33 sonic booms over KSC beginning on Aug 21st. Launches and other events at KSC have provided rich sources of signals that are useful to characterize and gain insight into physical processes and wave generation from man-made sources.

Ground Truth Collections for Explosions in Northern Fennoscandia and Russia

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

Harris, D B; Ringdal, F; Kremenetskaya, E

2003-07-28

This project is providing ground-truth information on explosions conducted at the principal mines within 500 kilometers of the ARCES station, and is assembling a seismic waveform database for these events from local and regional stations. The principal mines of interest are in northwest Russia (Khibiny Massif, Olenogorsk, Zapolyamy, and Kovdor groups) and Sweden (Malmberget, Kiruna). These mines form a natural laboratory for examining the variation of mining explosion observations with source type, since they include colocated surface and underground mines and mines conducting a variety of different shot types. In September 2002 we deployed two lines of temporary stations frommore » the Khibiny Massif through and to the north of the ARCES station. This deployment is producing data that will allow researchers to examine the variation of discriminants caused by varying source-receiver distance and the diversity of explosion types. To date, we have collected ground-truth information on 1,118 explosions in the Kola Peninsula, and have assembled waveform data for approximately 700 of these. The database includes waveforms from instruments temporarily deployed in the Khibiny Massif mines, from the Apatity network just outside of the Massif, from LVZ, KEV and ARCES, and from the stations deployed along the two lines into northern Norway. In this paper we present representative waveforms for several types of shots recorded at various regional distances. We have conducted a preliminary study of the variation of phase ratios as a function of source type. This study shows significant differences in Pd/Sn and Pd/Lg ratios for two types of mining explosions: surface ripple-fired explosions and compact underground explosions. Compact explosions are, typically, underground explosions of a few tons with only one or two short delays, and are the closest approximation to single, well-tamped explosions available in the Khibiny mines. The surface shots typically are much larger (ranging up to hundreds of tons), with many delays. The surface mine that we present results for typically also conducts several distinct shots across the mine nearly simultaneously (with a few seconds or tens of seconds). Measured phase ratios are more consistent for compact underground explosions. This consistency is an expected result given the smaller scope for shot variation in these smaller events. In addition, Pd/Lg ratios appear more stable than Pd/Sn ratios for both types of events. The most interesting result is that the compact underground explosions are richer in shear energy (i.e. having smaller P/S ratios) than their surface ripple-fired counterparts. We continue to work on an approach for identifying the principal mines to be targeted for screening at a particular station. Often, routine industrial blasts constitute a large proportion of events detected by monitoring stations close to major mining districts. Many mines may be present, and it may be a problem to determine which subset of mines is responsible for the majority of the events, and should be prime candidates for the deployment of ground-truth collection resources. Our solution to this problem entails several steps. The first is to find geographic clusters of events that may correspond to major groups of mines. For this step, we use event density maps generated from existing network catalogs. This year we examined some of the tradeoffs in generating event density maps: use of automated bulletins to produce maps vs. analyst-reviewed bulletins, and the amount of time required to produce stables maps which can be used to identify significant mines.« less

Main shock and aftershock records of the 1999 Izmit and Duzce, Turkey earthquakes

USGS Publications Warehouse

Celebi, M.; Akkar, Sinan; Gulerce, U.; Sanli, A.; Bundock, H.; Salkin, A.

2001-01-01

The August 17, 1999 Izmit (Turkey) earthquake (Mw=7.4) will be remembered as one of the largest earthquakes of recent times that affected a large urban environment (U.S. Geological Survey, 1999). This significant event was followed by many significant aftershocks and another main event (Mw=7.2) that occurred on November 12, 1999 near Duzce (Turkey). The shaking that caused the widespread damage and destruction was recorded by a handful of accelerographs (~30) in the earthquake area operated by different networks. The characteristics of these records show that the recorded peak accelerations, shown in Figure 1, even those from near field stations, are smaller than expected (Çelebi, 1999, 2000). Following this main event, several organizations from Turkey, Japan, France and the USA deployed temporary accelerographs and other aftershock recording hardware. Thus, the number of recording stations in the earthquake affected area was quadrupled (~130). As a result, as seen in Figure 2, smaller magnitude aftershocks yielded larger peak accelerations, indicating that because of the sparse networks, recording of larger motions during the main shock of August 17, 1999 were possibly missed.

StackSplit - a plugin for multi-event shear wave splitting analyses in SplitLab

NASA Astrophysics Data System (ADS)

Grund, Michael

2017-04-01

The SplitLab package (Wüstefeld et al., Computers and Geosciences, 2008), written in MATLAB, is a powerful and widely used tool for analysing seismological shear wave splitting of single event measurements. However, in many cases, especially temporary station deployments close to seaside or for recordings affected by strong anthropogenic noise, only multi-event approaches provide stable and reliable splitting results. In order to extend the original SplitLab environment for such analyses, I present the StackSplit plugin that can easily be implemented within the well accepted main program. StackSplit grants easy access to several different analysis approaches within SplitLab, including a new multiple waveform based inversion method as well as the most established standard stacking procedures. The possibility to switch between different analysis approaches at any time allows the user for the most flexible processing of individual multi-event splitting measurements for a single recording station. Besides the provided functions of the plugin, no other external program is needed for the multi-event analyses since StackSplit performs within the available SplitLab structure.

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

Toksoz, M N; Kuleli, S; Gurbuz, C

The objective of this project is to calibrate regional travel-times and propagation characteristics of seismic waves in Turkey and surrounding areas in the Middle East in order to enhance detection and location capabilities in the region. Important data for the project will be obtained by large calibration shots in central and eastern Turkey. The first, a two-ton shot, was fired in boreholes near Keskin in central Anatolia on 23 November 2002. The explosives were placed in 14 holes, each 80 m deep, arranged in concentric circular arrays. Ninety temporary seismic stations were deployed within a 300 km radius around themore » shot. The permanent stations of the Turkish National Seismic Network provided a good azimuthal coverage as well as three radial traverses. Most stations within a radius of 200 km recorded the shot. Travel-time data have been analyzed to obtain a detailed crustal model under the shot and along the profiles. The model gives a 35 km thick crust, characterized by two layers with velocities of 5.0 and 6.4 km/s. The P{sub n} velocity was found to be 7.8 km/s. The crustal thickness decreases to the north where the profile crosses the North Anatolian fault. There is a slight increase in crustal velocities, but no change in crustal thickness to the west. Data analysis effort is continuing to refine the regional velocity models and to obtain station corrections.« less

Space station structures development

NASA Technical Reports Server (NTRS)

Teller, V. B.

1986-01-01

A study of three interrelated tasks focusing on deployable Space Station truss structures is discussed. Task 1, the development of an alternate deployment system for linear truss, resulted in the preliminary design of an in-space reloadable linear motor deployer. Task 2, advanced composites deployable truss development, resulted in the testing and evaluation of composite materials for struts used in a deployable linear truss. Task 3, assembly of structures in space/erectable structures, resulted in the preliminary design of Space Station pressurized module support structures. An independent, redundant support system was developed for the common United States modules.

The 2012 Emilia seismic sequence (Northern Italy): Imaging the thrust fault system by accurate aftershock location

NASA Astrophysics Data System (ADS)

Govoni, Aladino; Marchetti, Alessandro; De Gori, Pasquale; Di Bona, Massimo; Lucente, Francesco Pio; Improta, Luigi; Chiarabba, Claudio; Nardi, Anna; Margheriti, Lucia; Agostinetti, Nicola Piana; Di Giovambattista, Rita; Latorre, Diana; Anselmi, Mario; Ciaccio, Maria Grazia; Moretti, Milena; Castellano, Corrado; Piccinini, Davide

2014-05-01

Starting from late May 2012, the Emilia region (Northern Italy) was severely shaken by an intense seismic sequence, originated from a ML 5.9 earthquake on May 20th, at a hypocentral depth of 6.3 km, with thrust-type focal mechanism. In the following days, the seismic rate remained high, counting 50 ML ≥ 2.0 earthquakes a day, on average. Seismicity spreads along a 30 km east-west elongated area, in the Po river alluvial plain, in the nearby of the cities Ferrara and Modena. Nine days after the first shock, another destructive thrust-type earthquake (ML 5.8) hit the area to the west, causing further damage and fatalities. Aftershocks following this second destructive event extended along the same east-westerly trend for further 20 km to the west, thus illuminating an area of about 50 km in length, on the whole. After the first shock struck, on May 20th, a dense network of temporary seismic stations, in addition to the permanent ones, was deployed in the meizoseismal area, leading to a sensible improvement of the earthquake monitoring capability there. A combined dataset, including three-component seismic waveforms recorded by both permanent and temporary stations, has been analyzed in order to obtain an appropriate 1-D velocity model for earthquake location in the study area. Here we describe the main seismological characteristics of this seismic sequence and, relying on refined earthquakes location, we make inferences on the geometry of the thrust system responsible for the two strongest shocks.

Along-strike variations in fault frictional properties along the San Andreas Fault near Cholame, California from joint earthquake and low-frequency earthquake relocations

USGS Publications Warehouse

Harrington, Rebecca M.; Cochran, Elizabeth S.; Griffiths, Emily M.; Zeng, Xiangfang; Thurber, Clifford H.

2016-01-01

Recent observations of low‐frequency earthquakes (LFEs) and tectonic tremor along the Parkfield–Cholame segment of the San Andreas fault suggest slow‐slip earthquakes occur in a transition zone between the shallow fault, which accommodates slip by a combination of aseismic creep and earthquakes (<15  km depth), and the deep fault, which accommodates slip by stable sliding (>35  km depth). However, the spatial relationship between shallow earthquakes and LFEs remains unclear. Here, we present precise relocations of 34 earthquakes and 34 LFEs recorded during a temporary deployment of 13 broadband seismic stations from May 2010 to July 2011. We use the temporary array waveform data, along with data from permanent seismic stations and a new high‐resolution 3D velocity model, to illuminate the fine‐scale details of the seismicity distribution near Cholame and the relation to the distribution of LFEs. The depth of the boundary between earthquakes and LFE hypocenters changes along strike and roughly follows the 350°C isotherm, suggesting frictional behavior may be, in part, thermally controlled. We observe no overlap in the depth of earthquakes and LFEs, with an ∼5  km separation between the deepest earthquakes and shallowest LFEs. In addition, clustering in the relocated seismicity near the 2004 Mw 6.0 Parkfield earthquake hypocenter and near the northern boundary of the 1857 Mw 7.8 Fort Tejon rupture may highlight areas of frictional heterogeneities on the fault where earthquakes tend to nucleate.

ViNEL: A Virtual Networking Lab for Cyber Defense Education

ERIC Educational Resources Information Center

Reinicke, Bryan; Baker, Elizabeth; Toothman, Callie

2018-01-01

Professors teaching cyber security classes often face challenges when developing workshops for their students: How does one quickly and efficiently configure and deploy an operating system for a temporary learning/testing environment? Faculty teaching these classes spend countless hours installing, configuring and deploying multiple system…

The BOrborema Deep Electromagnetic and Seismic (BODES) Experiment

NASA Astrophysics Data System (ADS)

Julià, J.; Garcia, X.; Medeiros, W. E.; Farias do Nascimento, A.

2015-12-01

The Borborema Province of NE Brazil is a large Precambrian domain of the Brazilian shield located in the Northeasternmost corner of South America. It is bounded by the Parnaíba basin to the West and by the São Francisco craton to the South. Its structuration in the Precambrian has been related to compressional processes during the Brasiliano-Pan African orogeny (600-550 Ma). In the Mesozoic, extensional stresses eventually leading to continental breakup, left a number of aborted rift basins within the Province. After continental breakup, the evolution of the Province was marked by episodes of uplift, which might have been coeval with episodes of Cenozoic volcanism. The most prominent expression of those uplift processes is the Borborema Plateau, an elliptically shaped topographic feature in the eastern half of the Province with maximum elevations of ~1200 m. The origin of uplift in the Plateau has been the focus of a number of multi-institutional and multi-disciplinary studies in the past few years, which have imaged the deep structure of the eastern Province with unprecedented detail. The origin of uplift in the western Province, which includes a superb example of basin inversion demonstrated by the ~1000 km elevations of the Chapada do Araripe, however, has been seldom investigated. With the goal of investigating the deep structure of the western Province, a temporary network of 10 collocated seismic and magnetotelluric stations was deployed in the region. The collocated stations were arranged in an approximately NS direction, with an interspation spacing of ~70 km and spanning a total length of ~600 km. The seismic stations consisted of broadband sensors (RefTek 151B-120 "Observer") sampling at 100 Hz and were deployed in January 2015; the MT stations consisted of long-period magnetotelluric (LEMI) systems, sampling at 1 Hz and 4 Hz, and were deployed in April 2015 for a period of ~2 weeks. Preliminary results based on teleseismic P-wave receiver functions suggest that the crust thickens towards the South, from 33 km in the Ceará domain to 44 km in the São Francisco craton. Preliminary analyis of MT data suggests a heterogeneous lithosphere, with marked changes in electrical properties around the Chapada do Araripe and a marked resistive structure towards the South, where the profile enters the São Francisco craton.

The BOrborema Deep Electromagnetic and Seismic (BODES) Experiment

NASA Astrophysics Data System (ADS)

Nemocon, A. M.; Garcia, X.; Julià, J.

2016-12-01

The Borborema Province of NE Brazil is a large Precambrian domain of the Brazilian shield located in the northeastern most corner of South America. It is bounded by the intracratonic Parnaíba basin to the West and by the mostly Archean São Francisco craton to the South, and its structuration has been related to compressional processes during the Brasiliano-Pan African orogeny (600-550 Ma). In the Mesozoic, extensional stresses related to the opening of the Atlantic ocean left a number of aborted rift basins within the Province. After continental breakup, the evolution of the Province was marked by episodes of uplift, which might have been coeval with episodes of volcanism in the Cenozoic. The most prominent expression of uplift is the Borborema Plateau, an elliptically shaped topographic feature in the eastern Province with maximum elevations of 1200 m. The origin of uplift across the Borborema Plateau has been the focus of a number of multi-disciplinary studies in the past few years, which have imaged the deep structure of the eastern Province with unprecedented detail. The origin of uplift in the western Province, which includes a superb example of basin inversion demonstrated through the 1000 km elevations of the Chapada do Araripe, however, has been seldom investigated. To alleviate this situation, a temporary network of 10 collocated seismic and magnetotelluric stations was deployed in the western Province. The collocated stations were arranged in an approximately NS direction, with an interstation spacing of 70 km and spanning a total length of 600 km. The seismic stations consisted of broadband sensors sampling at 100 Hz and were deployed in January 2015; the MT stations consisted of long-period magnetotelluric systems, sampling at 1 Hz and 4 Hz, and were deployed in April 2015 for a period of 2 weeks. Preliminary results based on P-receiver functions suggest that the crust thickens gradually to the South, from 36 km in the northern end of the profile to 44 km in the southern portion (São Francisco craton), while analysis of MT data suggests an heterogeneous lithosphere with marked lateral changes in electrical properties. Local thinning of the crust is observed under the Araripe basin, and a thickening resistive structure characterizes the lithospheric mantle under the craton.

A seismic network to investigate the sedimentary hosted hydrothermal Lusi system

NASA Astrophysics Data System (ADS)

Javad Fallahi, Mohammad; Mazzini, Adriano; Lupi, Matteo; Obermann, Anne; Karyono, Karyono

2016-04-01

The 29th of May 2006 marked the beginning of the sedimentary hosted hydrothermal Lusi system. During the last 10 years we witnessed numerous alterations of the Lusi system behavior that coincide with the frequent seismic and volcanic activity occurring in the region. In order to monitor the effect that the seismicity and the activity of the volcanic arc have on Lusi, we deployed a ad hoc seismic network. This temporary network consist of 10 broadband and 21 short period stations and is currently operating around the Arjuno-Welirang volcanic complex, along the Watukosek fault system and around Lusi, in the East Java basin since January 2015. We exploit this dataset to investigate surface wave and shear wave velocity structure of the upper-crust beneath the Arjuno-Welirang-Lusi complex in the framework of the Lusi Lab project (ERC grant n° 308126). Rayleigh and Love waves travelling between each station-pair are extracted by cross-correlating long time series of ambient noise data recorded at the stations. Group and phase velocity dispersion curves are obtained by time-frequency analysis of cross-correlation functions, and are tomographically inverted to provide 2D velocity maps corresponding to different sampling depths. 3D shear wave velocity structure is then acquired by inverting the group velocity maps.

A reference model for crust and uppermost mantle beneath Antarctica

NASA Astrophysics Data System (ADS)

Shen, W.; Wiens, D.; Gerstoft, P.; Bromirski, P. D.; Stephen, R. A.; Aster, R. C.; Nyblade, A.; Winberry, J. P.; Huerta, A. D.; Anandakrishnan, S.; Hansen, S. E.; Wilson, T. J.; Heeszel, D.

2016-12-01

Since the last decade of the 20th Century, over 300 broad-band seismic stations have been deployed across the continent of Antarctica (e.g., temporary networks such as TAMSEIS, AGAP/GAMSEIS, POLENET/ANET, TAMNNET and RIS/DRIS by US geoscientists, as well as stations deployed by other countries). In this presentation, we discuss our recent effort that builds a reference crustal and uppermost mantle shear velocity (Vs) model for continental Antarctica based on those seismic arrays. The data analysis for this effort consists of four steps. First, we compute ambient noise cross-correlations between all possible station pairs and use them to construct Rayleigh wave phase and group velocity maps at a continental scale. Coherence of the new maps with maps generated from teleseismic earthquake data from an earlier study (Heeszel et al., 2016) confirms the high quality of both maps and the minor difference helps quantify the map uncertainties. Second, we compute P receiver function waveforms for each station in Antarctica. Third, we collect Rayleigh waves generated by teleseismic earthquakes and measure their horizontal to vertical (H/V) ratio at each station. Fourth and finally, by combing all seismic measurements from the first three steps together with the phase velocity maps by Heeszel et al.(2016) using a non-linear Monte Carlo (MC) inversion algorithm, we built a 3-D model for the crust and uppermost mantle beneath continental Antarctica and its periphery to a depth of 150 km. This high resolution model, together with associated uncertainty estimates from the MC inversion, serve as a starting point for further improvement and geological interpretation. A variety of tectonic features, including a slower but highly heterogeneous West Antarctica and a much faster East Antarctica, are present in the 3D model. A better image of these features from the 3D model helps further investigation of the thermal and dynamic state of Antarctica's lithosphere and underlying asthenosphere and provides key constraints on the interaction of the solid earth with the West Antarctic Ice Sheet.

Gerst depressurized Kibo for Cubesat deployment

NASA Image and Video Library

2014-08-18

ISS040-E-096126 (18 Aug. 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, depressurizes the Kibo airlock in preparation for a series of NanoRacks CubeSat miniature satellite deployments. The first two pairs of nanosatellites are scheduled for deployment on Aug. 19. The Planet Labs Dove satellites that were carried to the station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25.

Gerst depressurized Kibo for Cubesat deployment

NASA Image and Video Library

2014-08-18

ISS040-E-096122 (18 Aug. 2014) --- In the International Space Station?s Kibo laboratory, European Space Agency astronaut Alexander Gerst, Expedition 40 flight engineer, depressurizes the Kibo airlock in preparation for a series of NanoRacks CubeSat miniature satellite deployments. The first two pairs of nanosatellites are scheduled for deployment on Aug. 19. The Planet Labs Dove satellites that were carried to the station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25.

New insights on co- and post-seismic deformation and slip behavior associated with the Mw7.8 2016 Pedernales, Ecuador earthquake and its aftershock sequence

NASA Astrophysics Data System (ADS)

Soto-Cordero, L.; Nealy, J. L.; Meltzer, A.; Agurto-Detzel, H.; Alvarado, A. P.; Beck, S. L.; Benz, H.; Bergman, E. A.; Charvis, P.; Font, Y.; Hayes, G. P.; Hernandez, S.; Hoskins, M.; Leon Rios, S.; Lynner, C.; Regnier, M. M.; Rietbrock, A.; Stachnik, J. C.; Yeck, W. L.

2017-12-01

On April 16, 2016, a Mw7.8 earthquake, associated with oblique subduction of the Nazca Plate under South America, ruptured a segment approximately 130x100km in the region north of the intersection of the Carnegie ridge with the Ecuador subduction zone. The rupture coincides with the rupture area of the Mw7.8 1942 earthquake. To characterize the aftershock sequence, we analyze seismic data recorded by 30 stations from April 17, 2016 to May 8, 2017; 11 stations belong to Ecuador's national network and 19 are part of a PASSCAL temporary deployment. We apply a kurtosis detector to obtain automatic P- and S-wave picks. Earthquake locations, magnitudes, and regional moment tensors are obtained using the U.S. Geological Survey National Earthquake Information Center (NEIC) processing system. We also determine calibrated relocations using the Hypocentroidal Decomposition approach for a subset of events for which we combine phase readings from local and temporary PASSCAL stations with regional and teleseismic phase readings from the NEIC. In contrast with other earthquake relocation approaches, this method evaluates absolute location uncertainties for each event in the cluster, which allows us to more confidently assess the relationships between mainshock slip and aftershock activity. We find the aftershock sequence is characterized by a series of event clusters that predominantly surround the main rupture patches. However, the aftershocks extend beyond the mainshock rupture area, covering a region approximately 250x100km. Aftershocks north of the 2016 rupture fall in the rupture area of the Mw7.7 1958 earthquake. The southernmost region of elevated seismicity occurs south of a region of low coupling where the Carnegie ridge meets the subduction zone. The characterization of this sequence allows a detailed spatial and temporal analysis of the rupture processes, stress patterns and slip behavior during this earthquake sequence in Ecuador subduction zone.

A Novel Methodology for Charging Station Deployment

NASA Astrophysics Data System (ADS)

Sun, Zhonghao; Zhao, Yunwei; He, Yueying; Li, Mingzhe

2018-02-01

Lack of charging stations has been a main obstacle to the promotion of electric vehicles. This paper studies deploying charging stations in traffic networks considering grid constraints to balance the charging demand and grid stability. First, we propose a statistical model for charging demand. Then we combine the charging demand model with power grid constraints and give the formulation of the charging station deployment problem. Finally, we propose a theoretical solution for the problem by transforming it to a Markov Decision Process.

Study on the three-station typical network deployments of workspace Measurement and Positioning System

NASA Astrophysics Data System (ADS)

Xiong, Zhi; Zhu, J. G.; Xue, B.; Ye, Sh. H.; Xiong, Y.

2013-10-01

As a novel network coordinate measurement system based on multi-directional positioning, workspace Measurement and Positioning System (wMPS) has outstanding advantages of good parallelism, wide measurement range and high measurement accuracy, which makes it to be the research hotspots and important development direction in the field of large-scale measurement. Since station deployment has a significant impact on the measurement range and accuracy, and also restricts the use-cost, the optimization method of station deployment was researched in this paper. Firstly, positioning error model was established. Then focusing on the small network consisted of three stations, the typical deployments and error distribution characteristics were studied. Finally, through measuring the simulated fuselage using typical deployments at the industrial spot and comparing the results with Laser Tracker, some conclusions are obtained. The comparison results show that under existing prototype conditions, I_3 typical deployment of which three stations are distributed in a straight line has an average error of 0.30 mm and the maximum error is 0.50 mm in the range of 12 m. Meanwhile, C_3 typical deployment of which three stations are uniformly distributed in the half-circumference of an circle has an average error of 0.17 mm and the maximum error is 0.28 mm. Obviously, C_3 typical deployment has a higher control effect on precision than I_3 type. The research work provides effective theoretical support for global measurement network optimization in the future work.

Mantle Structure Beneath East Africa and Zambia from Body Wave Tomography

NASA Astrophysics Data System (ADS)

Mulibo, G.; Nyblade, A.; Tugume, F.

2011-12-01

In this study, P and S travel time residuals from teleseismic earthquakes recorded on over 60 temporary AfricaArray seismic stations deployed in Uganda, Kenya, Tanzania and Zambia between 2007 and 2011 are being inverted, together with travel time residuals from previous deployments, for a 3D image of mantle wave speeds variations extending to a depth of 1200 km. Preliminary results show that at depths of 200 km of less, low wave speed anomalies are well developed beneath the Eastern and Western Branches of the East African Rift System. At deep depths, the low wave speed anomalies focus under the center and southern part of the East African Plateau and extend into the transition zone. At transition zone depths and within the top part of the lower mantle, the low wave speed anomaly shifts to the southwest beneath Zambia, indicating that the low wave speed anomaly is continuous across the transition zone and that it extends into the lower mantle. This result suggests that the upper mantle low wave speed anomaly beneath East Africa is connected to the African superplume anomaly in the lower mantle beneath southern Africa.

47 CFR 74.431 - Special rules applicable to remote pickup stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... damaged, stations licensed under Subpart D may be used to provide temporary circuits for a period not... SERVICES Remote Pickup Broadcast Stations § 74.431 Special rules applicable to remote pickup stations. (a..., frequency coordination, establishing microwave links, and operational communications. Operational...

47 CFR 74.431 - Special rules applicable to remote pickup stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... damaged, stations licensed under Subpart D may be used to provide temporary circuits for a period not... SERVICES Remote Pickup Broadcast Stations § 74.431 Special rules applicable to remote pickup stations. (a..., frequency coordination, establishing microwave links, and operational communications. Operational...

47 CFR 74.431 - Special rules applicable to remote pickup stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... damaged, stations licensed under Subpart D may be used to provide temporary circuits for a period not... SERVICES Remote Pickup Broadcast Stations § 74.431 Special rules applicable to remote pickup stations. (a..., frequency coordination, establishing microwave links, and operational communications. Operational...

47 CFR 74.431 - Special rules applicable to remote pickup stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... damaged, stations licensed under Subpart D may be used to provide temporary circuits for a period not... SERVICES Remote Pickup Broadcast Stations § 74.431 Special rules applicable to remote pickup stations. (a..., frequency coordination, establishing microwave links, and operational communications. Operational...

Emergency housing systems from three-dimensional engineered fiberboard : temporary building systems for lightweight, portable, easy-to-assemble, reusable, recyclable, and biodegradable structures

Treesearch

Jerrold E. Winandy; John F. Hunt; Christopher Turk; James R. Anderson

2006-01-01

Following natural disasters (such as hurricanes, tornados, or tsunamis), when civilians become displaced, or when military troops are deployed overseas, temporary housing is often a critical need. The USDA Forest Products Laboratory recently developed a lightweight, transportable, reusable, and recyclable biocomposite building material—threedimensional engineered...

Management of post midface distraction occlusal discrepancy using temporary anchorage devices in a cleft patient

PubMed Central

Koteswara Prasad, N. K.; Hussain, Syed Altaf; Chitharanjan, Arun B.; Murthy, Jyotsna

2015-01-01

Open bite deformity following a successful midface advancement by distraction osteogenesis is a common complication. Temporary anchorage devices can be deployed during the distraction and post-distraction settling phases for restoring the occlusion even in severe cases. The following report describes the management of severe anterior open bite following maxillary distraction. PMID:25991895

EarthScope's Transportable Array: Status of the Alaska Deployment and Guide to Resources for Lower48 Deployment

NASA Astrophysics Data System (ADS)

Busby, R. W.; Woodward, R.; Aderhold, K.; Frassetto, A.

2017-12-01

The Alaska Transportable Array deployment is completely installed, totaling 280 stations, with 194 new stations and 86 existing stations, 28 of those upgraded with new sensor emplacement. We briefly summarize the deployment of this seismic network, describe the added meteorological instruments and soil temperature gauges, and review our expectations for operation and demobilization. Curation of data from the contiguous Lower-48 States deployment of Transportable Array (>1800 stations, 2004-2015) has continued with the few gaps in real-time data replaced by locally archived files as well as minor adjustments in metadata. We highlight station digests that provide more detail on the components and settings of individual stations, documentation of standard procedures used throughout the deployment and other resources available online. In cooperation with IRIS DMC, a copy of the complete TA archive for the Lower-48 period has been transferred to a local disk to experiment with data access and software workflows that utilize most or all of the seismic timeseries, in contrast to event segments. Assembling such large datasets reliably - from field stations to a well managed data archive to a user's workspace - is complex. Sharing a curated and defined data volume with researchers is a potentially straightforward way to make data intensive analyses less difficult. We note that data collection within the Lower-48 continues with 160 stations of the N4 network operating at increased sample rates (100 sps) as part of the CEUSN, as operational support transitions from NSF to USGS.

Paving the Way for Small Satellite Access to Orbit: Cyclops' Deployment of SpinSat, the Largest Satellite Ever Deployed from the International Space Station

NASA Technical Reports Server (NTRS)

Hershey, Matthew P.; Newswander, Daniel R.; Smith, James P.; Lamb, Craig R.; Ballard, Perry G.

2015-01-01

The Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS), known as "Cyclops" to the International Space Station (ISS) community, successfully deployed the largest satellite ever (SpinSat) from the ISS on November 28, 2014. Cyclops, a collaboration between the NASA ISS Program, NASA Johnson Space Center Engineering, and Department of Defense Space Test Program (DoD STP) communities, is a dedicated 10-100 kg class ISS small satellite deployment system. This paper will showcase the successful deployment of SpinSat from the ISS. It will also outline the concept of operations, interfaces, requirements, and processes for satellites to utilize the Cyclops satellite deployment system.

Solidifying Small Satellite Access to Orbit via the International Space Station (ISS): Cyclops' Deployment of the Lonestar SmallSat from the ISS

NASA Technical Reports Server (NTRS)

Hershey, Matthew P.; Newswander, Daniel R.; Evernden, Brent A.

2016-01-01

On January 29, 2016, the Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS), known as "Cyclops" to the International Space Station (ISS) community, deployed Lonestar from the ISS. The deployment of Lonestar, a collaboration between Texas A&M University and the University of Texas at Austin, continued to showcase the simplicity and reliability of the Cyclops deployment system. Cyclops, a NASA-developed, dedicated 10-100 kg class ISS SmallSat deployment system, utilizes the Japanese airlock and robotic systems to seamlessly insert SmallSats into orbit. This paper will illustrate Cyclops' successful deployment of Lonestar from the ISS as well as outline its concept of operations, interfaces, requirements, and processes.

Space station mobile transporter

NASA Technical Reports Server (NTRS)

Renshall, James; Marks, Geoff W.; Young, Grant L.

1988-01-01

The first quarter of the next century will see an operational space station that will provide a permanently manned base for satellite servicing, multiple strategic scientific and commercial payload deployment, and Orbital Maneuvering Vehicle/Orbital Transfer Vehicle (OMV/OTV) retrieval replenishment and deployment. The space station, as conceived, is constructed in orbit and will be maintained in orbit. The construction, servicing, maintenance and deployment tasks, when coupled with the size of the station, dictate that some form of transportation and manipulation device be conceived. The Transporter described will work in conjunction with the Orbiter and an Assembly Work Platform (AWP) to construct the Work Station. The Transporter will also work in conjunction with the Mobile Remote Servicer to service and install payloads, retrieve, service and deploy satellites, and service and maintain the station itself. The Transporter involved in station construction when mounted on the AWP and later supporting a maintenance or inspection task with the Mobile Remote Servicer and the Flight Telerobotic Servicer is shown.

Passive seismic experiment and receiver functions analysis to determine crustal structure at the contact of the northern Dinarides and southwestern Pannonian Basin

NASA Astrophysics Data System (ADS)

Šumanovac, Franjo; Hegedűs, Endre; Orešković, Jasna; Kolar, Saša; Kovács, Attila C.; Dudjak, Darko; Kovács, István J.

2016-06-01

Passive seismic experiment was carried out at the SW contact of the Dinarides and Pannonian basin to determine the crustal structure and velocity discontinuities. The aim of the experiment was to define the relationship between the Adriatic microplate and the Pannonian segment as a part of the European plate. Most of the temporary seismic stations were deployed in Croatia along the Alp07 profile-a part of the active-source ALP 2002 project. About 300-km-long profile stretches from Istra peninsula to the Drava river, in a WSW-ESE direction. Teleseismic events recorded on 13 temporary seismic stations along the profile were analysed by P-receiver function method. Two types of characteristic receiver functions (RF) have been identified, belonging to Dinaridic and Pannonian crusts as defined on the Alp07 profile, while in transitional zone there are both types. Three major crustal discontinuities can be identified for the Dinaridic type: sedimentary basement, intracrustal discontinuity and Mohorovičić discontinuity, whereas the Pannonian type revealed only two discontinuities. The intracrustal discontinuity was not observed in the Pannonian type, thus pointing to a single-layered crust in the Pannonian basin. Two interpretation methods were applied: forward modelling of the receiver functions and H-κ stacking method, and the results were compared with the active-source seismic data at deep refraction profile Alp07. The receiver function modelling has given reliable results of the Moho depths that are in accordance with the seismic refraction results at the end of the Alp07 profile, that is in the area of Pannonian crust characterized by simple crustal structure and low seismic velocities (Vp between 5.9 and 6.2 km s-1). In the Dinarides and its peripheral parts, receiver function modelling regularly gives greater Moho depths, up to +15 per cent, due to more complex crustal structure. The depths of the Moho calculated by the H-κ stacking method vary within wide limits (±13 km), due to band limited data of short-period stations. The results at five stations have to be rejected because of huge deviations in comparison with all previous results, while at the other seven stations the Moho depths vary within ±15 per cent around the Moho discontinuity of the Alp07 profile.

Delineating Concealed Faults within Cogdell Oil Field via Earthquake Detection

NASA Astrophysics Data System (ADS)

Aiken, C.; Walter, J. I.; Brudzinski, M.; Skoumal, R.; Savvaidis, A.; Frohlich, C.; Borgfeldt, T.; Dotray, P.

2016-12-01

Cogdell oil field, located within the Permian Basin of western Texas, has experienced several earthquakes ranging from magnitude 1.7 to 4.6, most of which were recorded since 2006. Using the Earthscope USArray, Gan and Frohlich [2013] relocated some of these events and found a positive correlation in the timing of increased earthquake activity and increased CO2 injection volume. However, focal depths of these earthquakes are unknown due to 70 km station spacing of the USArray. Accurate focal depths as well as new detections can delineate subsurface faults and establish whether earthquakes are occurring in the shallow sediments or in the deeper basement. To delineate subsurface fault(s) in this region, we first detect earthquakes not currently listed in the USGS catalog by applying continuous waveform-template matching algorithms to multiple seismic data sets. We utilize seismic data spanning the time frame of 2006 to 2016 - which includes data from the U.S. Geological Survey Global Seismographic Network, the USArray, and the Sweetwater, TX broadband and nodal array located 20-40 km away. The catalog of earthquakes enhanced by template matching reveals events that were well recorded by the large-N Sweetwater array, so we are experimenting with strategies for optimizing template matching using different configurations of many stations. Since earthquake activity in the Cogdell oil field is on-going (a magnitude 2.6 occurred on May 29, 2016), a temporary deployment of TexNet seismometers has been planned for the immediate vicinity of Cogdell oil field in August 2016. Results on focal depths and detection of small magnitude events are pending this small local network deployment.

Deployable Debris Shields For Space Station

NASA Technical Reports Server (NTRS)

Christiansen, Eric L.; Cour-Palais, Burton G.; Crews, Jeanne

1993-01-01

Multilayer shields made of lightweight sheet materials deployed from proposed Space Station Freedom for additional protection against orbiting debris. Deployment mechanism attached at each location on exterior where extra protection needed. Equipment withdraws layer of material from storage in manner similar to unfurling sail or extending window shade. Number of layers deployed depends on required degree of protection, and could be as large as five.

Large Deployable Reflector (LDR) system concept and technology definition study. Analysis of space station requirements for LDR

NASA Astrophysics Data System (ADS)

Agnew, Donald L.; Vinkey, Victor F.; Runge, Fritz C.

1989-04-01

A study was conducted to determine how the Large Deployable Reflector (LDR) might benefit from the use of the space station for assembly, checkout, deployment, servicing, refurbishment, and technology development. Requirements that must be met by the space station to supply benefits for a selected scenario are summarized. Quantitative and qualitative data are supplied. Space station requirements for LDR which may be utilized by other missions are identified. A technology development mission for LDR is outlined and requirements summarized. A preliminary experiment plan is included. Space Station Data Base SAA 0020 and TDM 2411 are updated.

Large Deployable Reflector (LDR) system concept and technology definition study. Analysis of space station requirements for LDR

NASA Technical Reports Server (NTRS)

Agnew, Donald L.; Vinkey, Victor F.; Runge, Fritz C.

1989-01-01

A study was conducted to determine how the Large Deployable Reflector (LDR) might benefit from the use of the space station for assembly, checkout, deployment, servicing, refurbishment, and technology development. Requirements that must be met by the space station to supply benefits for a selected scenario are summarized. Quantitative and qualitative data are supplied. Space station requirements for LDR which may be utilized by other missions are identified. A technology development mission for LDR is outlined and requirements summarized. A preliminary experiment plan is included. Space Station Data Base SAA 0020 and TDM 2411 are updated.

Brady's Geothermal Field - Map of DAS, Nodal, Vibroseis and Reftek Station Deployment

DOE Data Explorer

Kurt Feigl

2016-10-15

Map of DAS, nodal, vibroseis and Reftek stations during March 2016 deployment. The plot on the left has nodal stations labeled; the plot on the right has vibroseis observations labeled. Stations are shown in map-view using Brady's rotated X-Y coordinates with side plots denoting elevation with respect to the WGS84 ellipsoid. Blue circles denote vibroseis data, x symbols denote DAS (cyan for horizontal and magenta for vertical), black asterisks denote Reftek data, and red plus signs denote nodal data. This map can be found on UW-Madison's askja server at /PoroTomo/DATA/MAPS/Deployment_Stations.pdf

1. EAST AND SOUTH SIDES OF STATION, SHOWING (LEFT BACKGROUND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. EAST AND SOUTH SIDES OF STATION, SHOWING (LEFT BACKGROUND TO CENTER FOREGROUND) SOUTH CANOPY, OPEN CONCOURSE ROOF, AND CONCOURSE ROOF EXTENSION (SMALL BUILDING UNDER CONCOURSE ROOF IS TEMPORARY AMTRAK STATION) - Pennsylvania Railroad Station, Open Concourse & Concourse Roof Extension, 1101 Liberty Avenue, Pittsburgh, Allegheny County, PA

47 CFR 80.37 - One authorization for a plurality of stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... authorize a designated maximum number of marine utility stations operating at temporary unspecified... 47 Telecommunication 5 2014-10-01 2014-10-01 false One authorization for a plurality of stations... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.37 One...

47 CFR 80.37 - One authorization for a plurality of stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... authorize a designated maximum number of marine utility stations operating at temporary unspecified... 47 Telecommunication 5 2012-10-01 2012-10-01 false One authorization for a plurality of stations... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.37 One...

47 CFR 80.37 - One authorization for a plurality of stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... authorize a designated maximum number of marine utility stations operating at temporary unspecified... 47 Telecommunication 5 2010-10-01 2010-10-01 false One authorization for a plurality of stations... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.37 One...

47 CFR 80.37 - One authorization for a plurality of stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... authorize a designated maximum number of marine utility stations operating at temporary unspecified... 47 Telecommunication 5 2013-10-01 2013-10-01 false One authorization for a plurality of stations... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.37 One...

47 CFR 80.37 - One authorization for a plurality of stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... authorize a designated maximum number of marine utility stations operating at temporary unspecified... 47 Telecommunication 5 2011-10-01 2011-10-01 false One authorization for a plurality of stations... SPECIAL RADIO SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.37 One...

47 CFR 74.633 - Temporary authorizations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... name and address, facility identification number of the associated broadcast station(s) (if any), call... wide-spread interest and importance which cannot be transmitted successfully on these frequencies...

The Precambrian crustal structure of East Africa

NASA Astrophysics Data System (ADS)

Young, A. J.; Tugume, F.; Nyblade, A.; Julia, J.; Mulibo, G.

2011-12-01

We present new results on crustal structure from East Africa from analyzing P wave receiver functions. The data for this study come from temporary AfricaArray broadband seismic stations deployed between 2007 and 2011 in Uganda, Tanzania and Zambia. Receiver functions have been computed using an iterative deconvolution method. Crustal structure has been imaged using the H-k stacking method and by jointly inverting the receiver functions and surface wave phase and group velocities. The results show remarkably uniform crust throughout the Archean and Proterozoic terrains that comprise the Precambrian tectonic framework of the region. Crustal thickness for most terrains is between 37 and 40 km, and Poisson's ratio is between 0.25 and 0.27. Results from the joint inversion yield average crustal Vs values of 3.6 to 3.7 km/s. For most terrains, a thin (1-5 km) thick high velocity (Vs>4.0 km/s) is found at the base of the crust.

Receiver function imaging of the mantle discontinuties beneath Fennoscandia and northern Europe

NASA Astrophysics Data System (ADS)

Frassetto, Andrew; Thybo, Hans

2010-05-01

Receiver functions from the Mantle Investigations of Norwegian Uplift Structure experiment (MAGNUS) are depth-converted using interval wavespeeds from AK-135 for the 410-km and 660-km discontinuities and combined using common-conversion-point stacking. This preliminary work shows a potentially complex mantle-transition-zone beneath southern Norway, with reduction in the amplitude of the 410-arrival and 20-30 km of shallowing of the 660-arrival beneath the axis of the Oslo Rift. To refine these measurements and place them in a regional context, we incorporate the MAGNUS dataset with permanent stations and previous temporary seismic deployments across Fennoscandia and northern Europe. New constraints on the depth to the lithosphere-asthenosphere boundary and character of the mantle-transition-zone will aid in understanding the causes for potentially recent uplift in the southern Scandes and the region of unusually slow upper mantle resolved beneath the region (Weidle and Maupin, 2008).

The Coso geothermal area: A laboratory for advanced MEQ studies for geothermal monitoring

USGS Publications Warehouse

Julian, B.R.; Foulger, G.R.; Richards-Dinger, K.

2004-01-01

The permanent 16-station network of three-component digital seismometers at the Coso geothermal area, California, supplemented by 14 temporary instruments deployed in connection with the DOE Enhanced Geothermal Systems (EGS) Project, provides high-quality microearthquake (MEQ) recordings that are well suited to monitoring a producing geothermal area. We are currently using these data to investigate structure and active processes within the geothermal reservoir by applying three advanced methods: a) high-precision MEQ hypocenter location; b) time-dependent tomography; c) complete (moment tensor) MEQ source mechanism determination. Preliminary results to date resolve seismogenic structures in the producing field more clearly than is possible with conventional earthquake-location techniques. A shallow part of the producing field shows clear changes in the ratio of the seismic wave speeds, Vp/V s, between 1996 and 2002, which are probably related to physical changes in the reservoir caused by fluid extraction.

Department of Defense Survey of Living Conditions Overseas. 1984. Volume 2. Results.

DTIC Science & Technology

1985-07-01

with less than 2 years of service) are also now married. 1 This new composition of the Armed Services has both changed the demand for housing and...locations begins with the first move into temporary lodgings upon arrival at the new duty station. These temporary lodgings may be government quarters on...current post, base, or duty station; the second, with the sponsor’s assistance in helping with the incoming family’s adjustment to the new situation. 36

NanoRack Cubesat Deployer (NRCSD) Operations

NASA Image and Video Library

2014-08-19

ISS040-E-100890 (19 Aug. 2014) --- Through a window in the International Space Station?s Kibo laboratory, an Expedition 40 crew member photographed the CubeSat deployer mechanism in the grasp of the Japanese robotic arm prior to a series of NanoRacks CubeSat miniature satellite deployments.

75 FR 49843 - Regulated Navigation Area; Boom Deployment Strategy Testing, Great Bay, NH

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-16

... vessels operating in the RNA during these boom deployments. As there will be hazards introduced to the... vessels are required to transit the RNA at bare steerageway and in a manner so as to produce no wake for...-1, paragraph (34)(g), of the Instruction as this rule involves establishing a temporary RNA. An...

On Deployment of Multiple Base Stations for Energy-Efficient Communication in Wireless Sensor Networks

DOE PAGES

Lin, Yunyue; Wu, Qishi; Cai, Xiaoshan; ...

2010-01-01

Data transmission from sensor nodes to a base station or a sink node often incurs significant energy consumption, which critically affects network lifetime. We generalize and solve the problem of deploying multiple base stations to maximize network lifetime in terms of two different metrics under one-hop and multihop communication models. In the one-hop communication model, the sensors far away from base stations always deplete their energy much faster than others. We propose an optimal solution and a heuristic approach based on the minimal enclosing circle algorithm to deploy a base station at the geometric center of each cluster. In themore » multihop communication model, both base station location and data routing mechanism need to be considered in maximizing network lifetime. We propose an iterative algorithm based on rigorous mathematical derivations and use linear programming to compute the optimal routing paths for data transmission. Simulation results show the distinguished performance of the proposed deployment algorithms in maximizing network lifetime.« less

The Installation of Satellite Modems on SEIS-UK Supported Remote Seismic Deployments

NASA Astrophysics Data System (ADS)

Horleston, A. C.; Brisbourne, A.; Hawthorn, D.

2006-12-01

SEIS-UK, as the UK's NERC funded national seismic equipment facility, is frequently involved in large, often remote, temporary seismic networks (running for up to 2 years). Up till now all these deployments have been managed solely by on-site maintenance but now SEIS-UK is investing in a number of satellite modems. The Michrosat 2400 OEM Modems, provided by Wireless Innovations Ltd, will be integrated within Guralp DCM data-logger units and will be used to provide regular state-of-health reports from remote networks. They will also provide the user the facility to communicate with the deployed systems, apply configuration changes and request system re-boots. This should lead to less instrument down-time and allow for more focussed site visits and thus, hopefully, reduce the cost (and servicing time) of remote installations. The Michrosat Modems are relatively low-powered and draw a maximum current of 2.5A (at 4.4v) for a few microseconds when initialising a call, dropping to bursts of approximately 1A when transmitting. This makes them ideally suited to temporary deployments relying on solar charged battery power. We will present examples of the configuration and typical deployment of the modems and the types of data transmitted.

An Overview of Seismic Observations Along the Pacific Margin of South America: Opportunities for the SZ4D Initiative

NASA Astrophysics Data System (ADS)

Woodward, R.; Frassetto, A.; Meltzer, A.

2017-12-01

The recent SZ4D Initiative community vision document recognizes the potential to focus community resources on studying subduction processes along, for example, the Pacific margin of South America. Preexisting geophysical infrastructure can play a vital role in establishing such new observational capabilities. For example, an SZ4D backbone observing capability could be established in South America by leveraging existing stations in the region. Such relevant existing seismic and geodetic stations, operated as part of local or national networks in South America, have been identified as a result of recent international collaborations with IRIS and others. Here we discuss the concept and experience of leveraging existing infrastructure in major new observational programs, outline the state of geophysical networks in South America (emphasizing current seismic networks but also looking back on historical temporary deployments), and provide an overview of potential scientific targets in the Americas that encompass a sampling of recently produced research results and datasets. Additionally, we reflect on strategies for establishing meaningful collaborations across South America and elsewhere, an aspect that will be critical to the international partnerships, and associated capacity building, needed for an internationally inclusive and collaborative SZ4D activity.

Project WILAS: Seismic imaging of crustal and upper mantle structures beneath the western Iberian Peninsula by means of the receiver-function technique

NASA Astrophysics Data System (ADS)

Dündar, Süleyman; Dias, Nuno A.; Silveira, Graça; Vinnik, Lev; Haberland, Christian

2013-04-01

An accurate knowledge of the structure of the earth's interior is of great importance to our understanding of tectonic processes. The WILAS-project (REF: PTDC/CTE-GIX/097946/2008) is a three-year collaborative project developed to study the subsurface structure of the western Iberian Peninsula, putting the main emphases on the lithosphere-asthenosphere system beneath the mainland of Portugal. The tectonic evolution of the target area has been driven by major plate-tectonic processes such as the historical opening of the Central Atlantic and the subsequent African-Eurasian convergence. Still, very little is known about the spatial structure of the continental collision. Within the framework of this research, a temporary network of 30 broadband three-component digital stations was operated between 2010 and 2012 in the target area. To carry out a large-scale structural analysis and facilitate a dense station-coverage for the area under investigation, the permanent Global Seismic Network stations, and temporary broadband stations deployed within the scope of the several seismic experiments (e.g. Doctar Network, Portuguese National Seismic Network), were included in the research analysis. In doing so, an unprecedented volume of high-quality data of a ca. 60X60 km density along with a combined network of 65 temporary and permanent broadband seismic stations are currently available for research purposes. One of the tasks of the WILAS research project has been a study of seismic velocity discontinuities beneath the western Iberian Peninsula region, up to a depth range of 700 km, utilizing the P- and S-receiver function techniques (PRF, SRF). Both techniques are based mainly on mode conversion of the elastic body-waves at an interface dividing the layers with different elastic properties. In the first phase of the project, PRF analysis was conducted in order to image the crust-mantle interface (Moho) and the mantle-transition-zone discontinuities at a depth of 410 km and 660 km beneath the area under investigation. While applying the common data processing steps (e.g., rotation, deconvolution and moveout-correction) to the selected data-set, we were able to create approximately 4.500 PRFs. The signals from the Moho, 410-km and 660-km discontinuities are clearly visible in many PRF stacks. The Moho depth range is from 26 to 34 km, with an average value of 29 km. No significant lateral variations in the depths of the "410-km" and "660-km" discontinuities have been identified so far. In the second phase of this project, the S-receiver-function technique will be applied in order to map the thickness of the underlying mantle lithosphere. Additionally, joint inversion of PRFs and waveforms of SKS will be used to investigate depth-localized azimuthal anisotropy and the related past and present mantle flows.

Mapping the influence of the deep Nazca slab on the geometry of the 660-km discontinuity beneath stable South America

NASA Astrophysics Data System (ADS)

Bianchi, M. B. D.; Assumpcao, M.; Julià, J.

2017-12-01

The fate of the deep Nazca subducted plate is poorly mapped under stable South America. Transition zone thickness and position is greatly dependent on mantle temperature and so is influenced by the colder Nazca plate position. We use a database of 35,000 LQT deconvolved receiver function traces to image the mantle transition zone and other upper mantle discontinuities under different terranes of stable South American continent. Data from the entire Brazilian Seismographic Network database, consisting of more than 80 broadband stations supplemented by 35 temporary stations deployed in west Brazil, Argentina, Paraguay, Bolivia and Uruguay were processed. Our results indicates that upper mantle velocities are faster than average under stable cratons and that most of the discontinuities are positioned with small variations in respect to nominal depths, except in places were the Nazca plate interacts with the transition zone. Under the Chaco-Pantanal basin the Nazca plate appears to be trapped in the transition zone for more than 1000 km with variations of up to 30 km in 660 km discontinuity topography under this region consistent with global tomographic models. Additional results obtained from SS precursor analysis of South Sandwich Islands teleseismic events recorded at USArray stations indicates that variations of transition zones thickness occur where the Nazca plate interacts with the upper mantle discontinuities in the northern part of Stable South American continent.

Existing Instrumentation and Scientific Drivers for a Subduction Zone Observatory in Latin America

NASA Astrophysics Data System (ADS)

Frassetto, A.; Woodward, R.; Detrick, R. S.

2015-12-01

The subduction zones along the western shore of the Americas provide numerous societally relevant scientific questions that have yet to be fully explored and would make an excellent target for a comprehensive, integrated Subduction Zone Observatory (SZO). Further, recent discussions in Latin America indicate that there are a large number of existing stations that could serve as a backbone for an SZO. Such preexisting geophysical infrastructure commonly plays a vital role in new science initiatives, from small PI-led experiments to the establishment of the USArray Transportable Array, Reference Network, Cascadia Amphibious Array, and the redeployment of EarthScope Transportable Array stations to Alaska. Creating an SZO along the western coast of the Americas could strongly leverage the portfolio of existing seismic and geodetic stations across regions of interest. In this presentation, we will discuss the concept and experience of leveraging existing infrastructure in major new observational programs, outline the state of geophysical networks in the Americas (emphasizing current seismic networks but also looking back on historical temporary deployments), and provide an overview of potential scientific targets in the Americas that encompass a sampling of recently produced research results and datasets. Additionally, we will reflect on strategies for establishing meaningful collaborations across Latin America, an aspect that will be critical to the international partnerships, and associated capacity building, needed for a successful SZO initiative.

Development of a Wireless Network of Temperature Sensors for Yellowstone National Park (USA)

NASA Astrophysics Data System (ADS)

Munday, D. A.; Hutter, T.; Minolli, M.; Obraczka, K.; Manduchi, R.; Petersen, S.; Lowenstern, J. B.; Heasler, H.

2007-12-01

Temperature sensors deployed at Yellowstone clearly document that thermal features can vary in temperature on a variety of timescales and show regional correlations unrelated to meteorological variables such as air temperature. Yellowstone National Park (YNP) staff currently measures temperatures at over 40 thermal features and streams within the park, utilizing USGS stream gaging stations and portable data loggers deployed in geyser basins. The latter measure temperature every 1 to 15 minutes, and the data are physically downloaded after about 30 days. Installation of a wireless sensor network would: 1) save considerable time and effort in data retrieval, 2) minimize lost data due to equipment failure, and 3) provide a means to monitor thermal perturbations in near-real time. To meet this need, we developed a wireless sensor network capable of in-situ monitoring of air and water temperature. Temperature sensors are dispersed as nodes that communicate among themselves and through relays to a single base-station linked to the Internet. The small, weatherproof sensors operate unattended for over six months at temperatures as low as -40°C. Each uses an ultra-low-power Texas Instruments' MSP430 microcontroller and an SD card as mass storage. They are powered by 15Ah, 3.6 v, inert Li-ion batteries and transmit data via 900MHz radio modules with a 1-km range. The initial prototype consists of 4 nodes, and is designed to scale with additional nodes for finer spatial resolution and broader coverage. Temperature measurements are asynchronous from node to node, with intervals as frequent as 30 seconds. Data are stored internally to withstand temporary communication failures; underlying intelligent software is capable of re-routing data through alternative nodes to the base station and a MySQL data archiving system. We also developed a Google-Maps-based, front-end that displays the data, recent trends and sensor locations. The system was tested in the Santa Cruz Mountains and will be used at Yellowstone National Park during Fall 2007.

Polarization Analysis of the September 2005 Northern Cascadia Episodic Tremor and Slip Event

NASA Astrophysics Data System (ADS)

Wech, A. G.; Creager, K. C.

2006-12-01

The region of Northern Cascadia, extending from the Olympic Mountains and Puget Sound to southern Vancouver Island, down-dip of the subduction "locked" zone has repeatedly experienced episodes of slow slip. This episodic slip, observed to take place over a period of two to several weeks, is accompanied by a seismic tremor signal. Based on the average recurrence interval of 14 months, the last episodic tremor and slip (ETS) event was expected to occur in September, 2005. Indeed, it began on September 3. In order to record this event, we deployed an array of 11 three-component seismometers on the northern side of the Olympic Peninsula augmenting Pacific Northwest Seismographic Network stations as well as the first few EarthScope BigFoot stations and Plate Boundary Observatory borehole seismometers. This seismic array was comprised of six short-period and five broadband instruments with average spacings of 500 m and 2200 m respectively. In conjunction with this Earthscope seismic deployment, we also installed a dense network of 29 temporary, continuous GPS stations across the entire Olympic Peninsula to integrate seismic and geodetic observations. Based on past geodetic observations, a dominant assumption for the source of tremor is fault-slip in the direction of subduction, which can be tested using polarization of the seismic tremor. Using waveform cross- correlation to invert for the direction of slowness, we observed the tremor signal to migrate directly under our array. As the source passed beneath the array, tremor polarization stabilized to coincide with the direction of subduction. During a four day period starting September 8, the normalized eigenvalue associated with the dominant linear polarization jumped from ~0.7 to a stable 0.9 value. Also during this time, the polarization azimuth stabilized to a value of 57 +/- 8 degrees, close to the angle of subduction (56 degrees) suggesting that the tremor is caused by slip in the direction of relative plate motion on one or more faults.

Dezhurov works in the sleep station in the U.S. Laboratory during Expedition Three

NASA Image and Video Library

2001-09-09

ISS003-E-5558 (9 September 2001) --- Cosmonaut Vladimir Dezhurov of Rosaviakosmos, Expedition 3 flight engineer, works on a laptop computer in the temporary sleep station of the in the U.S. Laboratory Destiny onboard the International Space Station.

NASA/DOD Control/Structures Interaction Technology, 1986

NASA Technical Reports Server (NTRS)

Wright, Robert L. (Compiler)

1986-01-01

Control/structures interactions, deployment dynamics and system performance of large flexible spacecraft are discussed. Spacecraft active controls, deployable truss structures, deployable antennas, solar power systems for space stations, pointing control systems for space station gimballed payloads, computer-aided design for large space structures, and passive damping for flexible structures are among the topics covered.

Investigation of the high-frequency attenuation parameter, κ (kappa), from aftershocks of the 2010 Mw 8.8 Maule, Chile earthquake

USGS Publications Warehouse

Neighbors, Corrie; Liao, E. J.; Cochran, Elizabeth S.; Funning, G. J.; Chung, A. I.; Lawrence, J. F.; Christensen, C. M.; Miller, M.; Belmonte, A.; Sepulveda, H. H. Andrés

2014-01-01

The Bío Bío region of Chile experienced a vigorous aftershock sequence following the 2010 February 27 Mw 8.8 Maule earthquake. The immediate aftershock sequence was captured by two temporary seismic deployments: the Quake Catcher Network Rapid Aftershock Mobilization Program (QCN RAMP) and the Incorporated Research Institutions for Seismology CHile Aftershock Mobilization Program (IRIS CHAMP). Here, we use moderate to large aftershocks (ML ≥ 4.0) occurring between 2010 March 1 and June 30 recorded by QCN RAMP and IRIS CHAMP stations to determine the spectral decay parameter, kappa (κ). First, we compare waveforms and κ estimates from the lower-resolution QCN stations to the IRIS CHAMP stations to ensure the QCN data are of sufficient quality. We find that QCN stations provide reasonable estimates of κ in comparison to traditional seismic sensors and provide valuable additional observations of local ground motion variation. Using data from both deployments, we investigate the variation in κ for the region to determine if κ is influenced primarily by local geological structure, path attenuation, or source properties (e.g. magnitude, mechanism and depth). Estimates of κ for the Bío Bío region range from 0.0022 to 0.0704 s with a mean of 0.0295 s and are in good agreement with κ values previously reported for similar tectonic environments. κ correlates with epicentral distance and, to a lesser degree, with source magnitude. We find little to no correlation between the site kappa, κ0, and mapped geology, although we were only able to compare the data to a low-resolution map of surficial geology. These results support an increasing number of studies that suggest κobservations can be attributed to a combination of source, path and site properties; additionally, measured κ are often highly scattered making it difficult to separate the contribution from each of these factors. Thus, our results suggest that contributions from the site, path and source should be carefully considered when interpreting κ values.

Linking ShakeMap and Emergency Managers in the Utah Region

NASA Astrophysics Data System (ADS)

Pankow, K.; Bausch, D.; Carey, B.

2007-12-01

In 2001, the University of Utah Seismograph Stations (UUSS) locally customized and began producing automatic ShakeMaps in Utah's Wasatch Front urban corridor as part of a new real-time earthquake information system developed under the Advanced National Seismic System. In 2005, motivated by requests from Utah's Division of Homeland Security and FEMA, ShakeMap capabilities were expanded to cover the entire Utah region. Now in 2007, ShakeMap capabilities throughout the region will again be enhanced by increased station coverage. The increased station coverage comes both from permanent stations funded by a state initiative and from the temporary deployment of EarthScope USArray stations. The state initiative will add ~22 strong-motion instruments and ~10 broadband instruments to the UUSS network. The majority of these stations will be located in southwestern Utah--one of the fastest growing regions in the U.S. EarthScope will evenly distribute 70 broadband stations in the region during 2007 that will be removed after 18 to 24 months. In addition to the enhanced station coverage for producing ShakeMaps in the Utah region, the transfer of information to the emergency response community is also being enhanced. First, tools are being developed that will link ShakeMap data with HAZUS loss-estimation software in near-real-time for rapid impact assessment. Second, ShakeMap scenarios are being used in conjunction with HAZUS loss-estimation software to produce customized maps for planning and preparedness exercises and also for developing templates that can be used following a significant regional earthquake. With the improvements to ShakeMap and the improved dialogue with the emergency managers, a suite of maps and information products were developed based on scenario earthquakes for training and exercise purposes. These products will be available in a timely fashion following a significant earthquake in the Utah region.

TexNet seismic network performance and reported seismicity in West Texas

NASA Astrophysics Data System (ADS)

Savvaidis, A.; Lomax, A.; Aiken, C.; Young, B.; Huang, D.; Hennings, P.

2017-12-01

In 2015, the Texas State Legislature began funding the Texas Seismological Network (TexNet). Since then, 22 new permanent broadband three-component seismic stations have been added to 17 existing stations operated by various networks [US, N4, IM]. These stations together with 4 auxiliary stations, i.e. long term deployments of 20 sec portable stations, were deployed to provide a baseline of Texas seismicity. As soon as the deployment of the new permanent stations took place in West Texas, TexNet was able to detect and characterize smaller magnitude events than was possible before, i.e. M < 2.5. As a consequence, additional portable stations were installed in the area in order to better map the current seismicity level. During the different stages of station deployment, we monitored the seismic network performance and its ability to detect earthquake activity. We found that a key limitation to the network performance is industrial noise in West Texas. For example, during daytime, phase picking and event detection rates are much lower than during nighttime at noisy sites. Regarding seismicity, the high density portable station deployment close to the earthquake activity minimizes hypocentral location uncertainties. In addition, we examined the effects of different crustal velocity models in the area of study on hypocentral location using the local network first arrivals. Considerable differences in location were obtained, which shows the importance of local networks and/or reliable crustal velocity models for West Texas. Given the levels of seismicity in West Texas, a plan to continuously monitor the study area is under development.

47 CFR 25.120 - Application for special temporary authorization.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... (c) Each application proposing construction of one or more earth station antennas or alteration of the overall height of one or more existing earth station antenna structures, where FAA notification... Antenna Structure Registration Number(s) for the affected satellite earth station antenna(s). If no such...

47 CFR 25.120 - Application for special temporary authorization.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... (c) Each application proposing construction of one or more earth station antennas or alteration of the overall height of one or more existing earth station antenna structures, where FAA notification... Antenna Structure Registration Number(s) for the affected satellite earth station antenna(s). If no such...

47 CFR 25.120 - Application for special temporary authorization.

Code of Federal Regulations, 2011 CFR

2011-10-01

.... (c) Each application proposing construction of one or more earth station antennas or alteration of the overall height of one or more existing earth station antenna structures, where FAA notification... Antenna Structure Registration Number(s) for the affected satellite earth station antenna(s). If no such...

47 CFR 25.120 - Application for special temporary authorization.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... (c) Each application proposing construction of one or more earth station antennas or alteration of the overall height of one or more existing earth station antenna structures, where FAA notification... Antenna Structure Registration Number(s) for the affected satellite earth station antenna(s). If no such...

47 CFR 25.120 - Application for special temporary authorization.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... (c) Each application proposing construction of one or more earth station antennas or alteration of the overall height of one or more existing earth station antenna structures, where FAA notification... Antenna Structure Registration Number(s) for the affected satellite earth station antenna(s). If no such...

47 CFR 74.537 - Temporary authorizations.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

47 CFR 74.537 - Temporary authorizations.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

47 CFR 74.537 - Temporary authorizations.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

Postdeployment Respiratory Health Care Encounters Following Deployment to Kabul, Afghanistan: A Retrospective Cohort Study.

PubMed

Sharkey, Jessica M; Abraham, Joseph H; Clark, Leslie L; Rohrbeck, Patricia; Ludwig, Sharon L; Hu, Zheng; Baird, Coleen P

2016-03-01

Inhalational hazards are numerous in operational environments. A retrospective cohort study was conducted to investigate associations between deployment to Kabul, Afghanistan and subsequent respiratory health among U.S. military personnel. The study population consisted of personnel who deployed to Kabul, select Operation Enduring Freedom locations, personnel stationed in the Republic of Korea, and U.S.-stationed personnel. Incidence rate ratios (IRRs) were estimated for respiratory symptoms, signs, and ill-defined conditions, asthma, and chronic obstructive pulmonary disease. A significantly elevated rate of symptoms, signs, and ill-defined conditions was observed among Kabul-deployed personnel compared to personnel deployed or stationed in Bagram (IRR 1.12; 95% confidence interval [CI], 1.05-1.19), Republic of Korea (IRR 1.20; 95% CI, 1.10-1.31), and the United States (IRR 1.52; 95% CI, 1.43-1.62). A statistically elevated rate of asthma was observed among personnel deployed to Kabul, relative to U.S.-stationed personnel (IRR 1.61; 95% CI, 1.22-2.12). Statistically significant rates were not observed for chronic obstructive pulmonary disease among Kabul-deployed personnel compared to other study groups. These findings suggest that deployment to Kabul is associated with an elevated risk of postdeployment respiratory symptoms and new-onset asthma. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

P- and S- wave velocity structure in and around the Itoigawa-Shizuoka Tectonic Line (ISTL) fault system revealed by dense seismic array observations

NASA Astrophysics Data System (ADS)

Panayotopoulos, Y.; Hirata, N.; Sato, H.; Iwasaki, T.; Kato, A.; Imanishi, K.; Kuwahara, Y.; Cho, I.

2008-12-01

The ISTL is a major tectonic structure that divides the Japanese Island arc into northeast and southwest parts. It was formed as a normal fault in the early Miocene and represents the southwestern boundary of the northern Fossa Mangna rift basin to the north, and the boundary between the Japanese arc accretionary prism units and the Izu-Bonin arc crust to the south. Previous studies have provided the sallow structure of the different ISTL fault segments, but the detailed crustal structure along the ISTL is yet to be revealed. The online permanent seismic station network in the area is not sufficient to accurately locate the earthquakes occurring in the area and also not dense enough to provide a detailed structure of the earth's crust. Over the past 3 years we have installed temporary seismic stations along the STL. We have deployed 60 stations in the southern, 58 stations in the central and 60 stations in the northern ISTL regions. We have combined the data retrieved from the temporary stations with the data available from the online permanent stations in the ISTL area and manually re-picked 63,275 P- and 68,847 S- wave arrival times from 1,945 events from the 5th August 2003 to 31st December 2006. The Double Difference tomography method (Zhang and Thurber, 2003) was used in order to accurately relocate the hypocenters and obtain a 3D P- and S- wave velocity (Vp and Vs) structure beneath the ISTL fault system. The relocated hypocenters in the southern ISTL coincide with the deeper extension of the active faults in the area. The relocated hypocenters are deeper than those reported by the Japan Meteorological Agency (JMA) in the northern ISTL and shallower at the central and southern parts. The average depth of the hypocenters is shallower in the northern ISTL (3 - 8 km) and gets progressively deeper towards the central (8-15 km) and southern (15-25 km) ISTL. The tomographic analysis has provided a detailed Vp and Vs image of the crust in the area below the ISTL. The 3D velocity model that we have acquired of the crustal structure in the area is in accordance with the geological boundaries. The northern tomograms fit accurately with the deeper extension of the Matsumoto basin and the central uplift zone geological units. In the central ISTL, the Yatsugatake volcano magmatic conduit was imaged. In the southern ISTL, we imaged the downwards continuation of the low grade metamorphic rocks that constitute the Chichibu-Shimanto belts of the southwest acrretionary prism of the Japanese arc, and of the igneous rocks that form the Izu-Bonin arc crust.

Tectonic Setting and Aftershocks of the Mw 6.7 Feburary 14, 2013 Earthquake in Yakutia, Northeast Russia

NASA Astrophysics Data System (ADS)

Rappolee, E.; Burk, D. R.; Mackey, K. G.; Fujita, K.; Shibaev, S. V.; Koz'min, B. M.

2016-12-01

The details of the seismotectonics along the boundary between the Eurasian, North American, and Okhotsk plates are poorly understood. Infrequent earthquakes of moderate size (Mw > 4) in this remote region make it difficult to characterize its tectonic activity. On February 14, 2013, an Mw 6.7 earthquake along this boundary in Northern Yakutia, Russia, resulted in a long sequence of aftershocks that provide an opportunity to better understand the region's geology. A temporary deployment of four seismic stations was installed around the main shock to supplement regional station coverage. During the ten day deployment, several thousand aftershocks were recorded. We have located 112 events using both first-arriving Pn and Sn and secondary arriving Pg and Sg phase time picks. The located aftershocks define a SSE striking zone approximately 30 km long and 10 km wide, east of the Illin'-Tas fault and northwest of the Indigirka River. Location depths range from 0 to 20 km. In conjunction with locating aftershocks, a local three-layer best-fit velocity was determined consisting of an upper crust (14 km thick, VPg = 6.06 km/s and VSg = 3.53 km/s), a lower crust (21 km thick, VP* = 6.45 km/s and VS* = 3.65 km/s), and a Moho (35 km deep, VPn = 7.98 km/s and VSn = 4.53 km/s). The mainshock epicenter falls in the northwestern corner of the aftershock zone, however its focal depth is not well established. Aftershock analysis is ongoing and will possibly provide a better understanding of the earthquake rupture zone. Nonetheless, results of this study support active thrusting and mountain building as a mechanism to accommodate compression along the North America-Eurasia boundary.

Semiautomated tremor detection using a combined cross-correlation and neural network approach

USGS Publications Warehouse

Horstmann, Tobias; Harrington, Rebecca M.; Cochran, Elizabeth S.

2013-01-01

Despite observations of tectonic tremor in many locations around the globe, the emergent phase arrivals, low‒amplitude waveforms, and variable event durations make automatic detection a nontrivial task. In this study, we employ a new method to identify tremor in large data sets using a semiautomated technique. The method first reduces the data volume with an envelope cross‒correlation technique, followed by a Self‒Organizing Map (SOM) algorithm to identify and classify event types. The method detects tremor in an automated fashion after calibrating for a specific data set, hence we refer to it as being “semiautomated”. We apply the semiautomated detection algorithm to a newly acquired data set of waveforms from a temporary deployment of 13 seismometers near Cholame, California, from May 2010 to July 2011. We manually identify tremor events in a 3 week long test data set and compare to the SOM output and find a detection accuracy of 79.5%. Detection accuracy improves with increasing signal‒to‒noise ratios and number of available stations. We find detection completeness of 96% for tremor events with signal‒to‒noise ratios above 3 and optimal results when data from at least 10 stations are available. We compare the SOM algorithm to the envelope correlation method of Wech and Creager and find the SOM performs significantly better, at least for the data set examined here. Using the SOM algorithm, we detect 2606 tremor events with a cumulative signal duration of nearly 55 h during the 13 month deployment. Overall, the SOM algorithm is shown to be a flexible new method that utilizes characteristics of the waveforms to identify tremor from noise or other seismic signals.

Semiautomated tremor detection using a combined cross-correlation and neural network approach

NASA Astrophysics Data System (ADS)

Horstmann, T.; Harrington, R. M.; Cochran, E. S.

2013-09-01

Despite observations of tectonic tremor in many locations around the globe, the emergent phase arrivals, low-amplitude waveforms, and variable event durations make automatic detection a nontrivial task. In this study, we employ a new method to identify tremor in large data sets using a semiautomated technique. The method first reduces the data volume with an envelope cross-correlation technique, followed by a Self-Organizing Map (SOM) algorithm to identify and classify event types. The method detects tremor in an automated fashion after calibrating for a specific data set, hence we refer to it as being "semiautomated". We apply the semiautomated detection algorithm to a newly acquired data set of waveforms from a temporary deployment of 13 seismometers near Cholame, California, from May 2010 to July 2011. We manually identify tremor events in a 3 week long test data set and compare to the SOM output and find a detection accuracy of 79.5%. Detection accuracy improves with increasing signal-to-noise ratios and number of available stations. We find detection completeness of 96% for tremor events with signal-to-noise ratios above 3 and optimal results when data from at least 10 stations are available. We compare the SOM algorithm to the envelope correlation method of Wech and Creager and find the SOM performs significantly better, at least for the data set examined here. Using the SOM algorithm, we detect 2606 tremor events with a cumulative signal duration of nearly 55 h during the 13 month deployment. Overall, the SOM algorithm is shown to be a flexible new method that utilizes characteristics of the waveforms to identify tremor from noise or other seismic signals.

A deployment of broadband seismic stations in two deep gold mines, South Africa

USGS Publications Warehouse

McGarr, Arthur F.; Boettcher, Margaret S.; Fletcher, Jon Peter B.; Johnston, Malcolm J.; Durrheim, R.; Spottiswoode, S.; Milev, A.

2009-01-01

In-mine seismic networks throughout the TauTona and Mponeng gold mines provide precise locations and seismic source parameters of earthquakes. They also support small-scale experimental projects, including NELSAM (Natural Earthquake Laboratory in South African Mines), which is intended to record, at close hand, seismic rupture of a geologic fault that traverses the project region near the deepest part of TauTona. To resolve some questions regarding the in-mine and NELSAM networks, we deployed four portable broadband seismic stations at deep sites within TauTona and Mponeng for one week during September 2007 and recorded ground acceleration. Moderately large earthquakes within our temporary network were recorded with sufficiently high signal-to-noise that we were able to integrate the acceleration to ground velocity and displacement, from which moment tensors could be determined. We resolved the questions concerning the NELSAM and in-mine networks by using these moment tensors to calculate synthetic seismograms at various network recording sites for comparison with the ground motion recorded at the same locations. We also used the peak velocity of the S wave pulse, corrected for attenuation with distance, to estimate the maximum slip within the rupture zone of an earthquake. We then combined the maximum slip and seismic moment with results from laboratory friction experiments to estimate maximum slip rates within the same high-slip patches of the rupture zone. For the four largest earthquakes recorded within our network, all with magnitudes near 2, these inferred maximum slips range from 4 to 27 mm and the corresponding maximum slip rates range from 1 to 6 m/s. These results, in conjunction with information from previous ground motion studies, indicate that underground support should be capable of withstanding peak ground velocities of at least 5 m/s.

The Caucasus Seismic Network (CNET): Seismic Structure of the Greater and Lesser Caucasus

NASA Astrophysics Data System (ADS)

Sandvol, E. A.; Mackey, K. G.; Nabelek, J.; Yetermishli, G.; Godoladze, T.; Babayan, H.; Malovichko, A.

2017-12-01

The Greater Caucasus are a portion of the Alpine-Himalayan mountain belt that has undergone rapid uplift in the past 5 million years, thus serving as a unique natural laboratory to study the early stages of orogenesis. Relatively lower resolution seismic velocity models of this region show contradictory lateral variability. Furthermore, recent waveform modeling of seismograms has clearly demonstrated the presence of deep earthquakes (with a maximum hypocentral depth of 175 km) below the Greater Caucasus. The region has been largely unexplored in terms of the detailed uppermost mantle and crustal seismic structure due in part to the disparate data sets that have not yet been merged as well as key portions being sparsely instrumented. We have established collaborative agreements across the region. Building on these agreements we recently deployed a major multi-national seismic array across the Greater Caucasus to address fundamental questions about the nature of continental deformation in this poorly understood region. Our seismic array has two components: (1) a grid of stations spanning the entire Caucasus and (2) two seismic transects consisting of stations spaced at distances of less than 10 km that cross the Greater Caucasus. In addition to the temporary stations, we are working to integrate data from the national networks to produce high resolution images of the seismic structure. Using data from over 106 new seismic stations in Azerbaijan, Armenia, Russia, and Georgia, we hope to gain a better understanding of the recent uplift ( 5 Ma) of the Greater Caucasus and the nature of seismogenic deformation in the region.

Engineering challenges of operating year-round portable seismic stations at high-latitude

NASA Astrophysics Data System (ADS)

Beaudoin, Bruce; Carpenter, Paul; Hebert, Jason; Childs, Dean; Anderson, Kent

2017-04-01

Remote portable seismic stations are, in most cases, constrained by logistics and cost. High latitude operations introduce environmental, technical and logistical challenges that require substantially more engineering work to ensure robust, high quality data return. Since 2006, IRIS PASSCAL has been funded by NSF to develop, deploy, and maintain a pool of polar specific seismic stations. Here, we describe our latest advancements to mitigate the challenges of high-latitude, year-round station operation. The IRIS PASSCAL program has supported high-latitude deployments since the late 1980s. These early deployments were largely controlled source, summer only experiments. In early 2000 PASSCAL users began proposing year-round deployments of broadband stations in some of the harshest environments on the planet. These early year-round deployments were stand-alone (no telemetry) stations largely designed to operate during summer months and then run as long as possible during the winter with hopes the stations would revive come following summer. In 2006 and in collaboration with UNAVCO, we began developing communications, power systems, and enclosures to extend recording to year-round. Since this initial effort, PASSCAL continued refinement to power systems, enclosure design and manufacturability, and real-time data communications. Several sensor and data logger manufacturers have made advances in cold weather performance and delivered newly designed instruments that have furthered our ability to successfully run portable stations at high-latitude with minimal logistics - reducing size and weight of instruments and infrastructure. All PASSCAL polar engineering work is openly shared through our website: www.passcal.nmt.edu/content/polar

Improving liquid bait programs for Argentine ant control: bait station density.

PubMed

Nelson, Erik H; Daane, Kent M

2007-12-01

Argentine ants, Linepithema humile (Mayr), have a positive effect on populations of mealybugs (Pseudococcus spp.) in California vineyards. Previous studies have shown reductions in both ant activity and mealybug numbers after liquid ant baits were deployed in vineyards at densities of 85-620 bait stations/ha. However, bait station densities may need to be <85 bait stations/ha before bait-based strategies for ant control are economically comparable to spray-based insecticide treatments-a condition that, if met, will encourage the commercial adoption of liquid baits for ant control. This research assessed the effectiveness of baits deployed at lower densities. Two field experiments were conducted in commercial vineyards. In experiment 1, baits were deployed at 54-225 bait stations/ha in 2005 and 2006. In experiment 2, baits were deployed at 34-205 bait stations/ha in 2006 only. In both experiments, ant activity and the density of mealybugs in grape fruit clusters at harvest time declined with increasing bait station density. In 2005 only, European fruit lecanium scale [Parthenolecanium corni (Bouché)] were also present in fruit clusters, and scale densities were negatively related to bait station density. The results indicate that the amount of ant and mealybug control achieved by an incremental increase in the number of bait stations per hectare is constant across a broad range of bait station densities. The results are discussed in the context of commercializing liquid ant baits to provide a more sustainable Argentine ant control strategy.

Preliminary Results of Crustal Structure beneath the Wabash Valley Seismic Zone Using Teleseismic Receiver Functions and Ambient Noise Tomography

NASA Astrophysics Data System (ADS)

Zhu, L.; Aziz Zanjani, A.; Hu, S.; Liu, Y.; Herrmann, R. B.; Conder, J. A.

2015-12-01

As part of a on-going EarthScope FlexArray project, we deployed 45 broadband seismographs in a 300-km-long linear profile across the Wabash Valley Seismic Zone (WVSZ). Here we present preliminary results of crustal structure beneath WVSZ based on teleseismic receiver functions and ambient noise tomography. We combined waveform data of the temporary stations in 2014 with those of permanent seismic stations and the transportable array stations in our study area since 2011. We found 656 teleseismic events with clear P-wave signals and obtained 2657 good-quality receiver functions of 84 stations using a time-domain iterative deconvolution method. We estimated crustal thickness and Vp/Vs ratio beneath each station using the H-κ stacking method. A high-resolution crustal structural image along the linear profile was obtained using the Common-Conversion-Point (CCP) stacking method. We also measured Rayleigh-wave phase and group velocities from 5 to 50 s by cross-correlating ambient noises between stations and did joint-inversion of receiver functions and surface wave dispersions for S-velocity structures beneath selected stations. The results show that the average crustal thickness in the region is 47 km with a gentle increase of crustal thickness from southeast to northwest. A mid-crustal interface is identified in the CCP image that also deepens from 15 km in the southeastern end to >20 km in the northwest. The CCP image shows that the low-velocity sedimentary layer along the profile is broad and is thickest (~10 km) near the center of the Wabash Valley. Beneath the center of the Valley there is a 40-km-wide positive velocity discontinuity at a depth of 40 km in the lower crust that might be the top of a rift pillow in this failed continental rift. Further results using 3D joint inversion and CCP migration will be presented at the meeting.

Application of Subspace Detection to the 6 November 2011 M5.6 Prague, Oklahoma Aftershock Sequence

NASA Astrophysics Data System (ADS)

McMahon, N. D.; Benz, H.; Johnson, C. E.; Aster, R. C.; McNamara, D. E.

2015-12-01

Subspace detection is a powerful tool for the identification of small seismic events. Subspace detectors improve upon single-event matched filtering techniques by using multiple orthogonal waveform templates whose linear combinations characterize a range of observed signals from previously identified earthquakes. Subspace detectors running on multiple stations can significantly increasing the number of locatable events, lowering the catalog's magnitude of completeness and thus providing extraordinary detail on the kinematics of the aftershock process. The 6 November 2011 M5.6 earthquake near Prague, Oklahoma is the largest earthquake instrumentally recorded in Oklahoma history and the largest earthquake resultant from deep wastewater injection. A M4.8 foreshock on 5 November 2011 and the M5.6 mainshock triggered tens of thousands of detectable aftershocks along a 20 km splay of the Wilzetta Fault Zone known as the Meeker-Prague fault. In response to this unprecedented earthquake, 21 temporary seismic stations were deployed surrounding the seismic activity. We utilized a catalog of 767 previously located aftershocks to construct subspace detectors for the 21 temporary and 10 closest permanent seismic stations. Subspace detection identified more than 500,000 new arrival-time observations, which associated into more than 20,000 locatable earthquakes. The associated earthquakes were relocated using the Bayesloc multiple-event locator, resulting in ~7,000 earthquakes with hypocentral uncertainties of less than 500 m. The relocated seismicity provides unique insight into the spatio-temporal evolution of the aftershock sequence along the Wilzetta Fault Zone and its associated structures. We find that the crystalline basement and overlying sedimentary Arbuckle formation accommodate the majority of aftershocks. While we observe aftershocks along the entire 20 km length of the Meeker-Prague fault, the vast majority of earthquakes were confined to a 9 km wide by 9 km deep surface striking N54°E and dipping 83° to the northwest near the junction of the splay with the main Wilzetta fault structure. Relocated seismicity shows off-fault stress-related interaction to distances of 10 km or more from the mainshock, including clustered seismicity to the northwest and southeast of the mainshock.

Aftershock Analysis of the 2016 Mw7.8 Pedernales (Ecuador) Earthquake: Seismotectonics, Seismicity Distribution and Relationship with Coseismic Slip Distribution

NASA Astrophysics Data System (ADS)

Agurto-Detzel, H.; Font, Y.; Charvis, P.; Ambrois, D.; Cheze, J.; Courboulex, F.; De Barros, L.; Deschamps, A.; Galve, A.; Godano, M.; Laigle, M.; Maron, C.; Martin, X.; Monfret, T.; Oregioni, D.; Peix, F., Sr.; Regnier, M. M.; Yates, B.; Mercerat, D.; Leon Rios, S.; Rietbrock, A.; Acero, W.; Alvarado, A. P.; Gabriela, P.; Ramos, C.; Ruiz, M. C.; Singaucho, J. C.; Vasconez, F.; Viracucha, C.; Beck, S. L.; Lynner, C.; Hoskins, M.; Meltzer, A.; Soto-Cordero, L.; Stachnik, J.

2017-12-01

0n April 2016, a Mw 7.8 megathrust earthquake struck the coast of Ecuador causing vast human and material losses. The earthquake ruptured a 100 km-long segment of the subduction interface between Nazca and South America, spatially coinciding with the 1942 M 7.8 earthquake rupture area. Shortly after the mainshock, an international effort made by institutions from Ecuador, France, UK and USA, deployed a temporary network of +60 land and ocean-bottom seismometers to capture the aftershock sequence for the subsequent year. These stations came to join the local Ecuadorian national network already monitoring in place. Here we benefit from this dataset to produce a suite of automatic locations and a subset of regional moment tensors for high quality events. Over 2900 events were detected for the first month of postseismic activity alone, and a subset of 600 events were manually re-picked and located. Similarly, thousands of aftershocks were detected using the temporary deployment over the following months, with magnitudes ranging between 1 to 7. As expected, moment tensors show mostly thrust faulting at the interface, but we also observe sparse normal and strike-slip faulting at shallow depths in the forearc. The spatial distribution of seismicity delineates the coseismic rupture area, but extends well beyond it over a 300 km long segment. Main features include three seismicity alignments perpendicular to the trench, at the north, center and south of the mainshock rupture. Preliminary results comparing quantitatively the distribution of aftershocks to the distribution of the coseismic rupture show that the bulk of the aftershock seismicity occurs at intermediate levels of coseismic slip, while areas of maximum coseismic slip are mostly devoid of events M>3. Our results shed light on the interface processes occurring mainly during the early post-seismic period of large megathrust earthquakes, and implications on the earthquake cycle.

Dezhurov works in the sleep station in the U.S. Laboratory during Expedition Three

NASA Image and Video Library

2001-09-09

ISS003-E-5560 (9 September 2001) --- Cosmonaut Vladimir Dezhurov of Rosaviakosmos, Expedition Three flight engineer, works on a laptop computer in the Temporary Sleep Station (TSS) in the U.S. Laboratory.

76 FR 71888 - Federal Travel Regulation (FTR); Storage of a Privately Owned Vehicle When Assigned a Temporary...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-21

...This final rule amends the Federal Travel Regulation (FTR), and allows agencies to establish internal policy and procedures for storage of a privately owned vehicle (POV) when an employee is assigned a temporary change of station (TCS) in support of a contingency operation.

Space Station tethered refueling facility operations

NASA Technical Reports Server (NTRS)

Kiefel, E. R.; Rudolph, L. K.; Fester, D. A.

1986-01-01

The space-based orbital transfer vehicle will require a large cryogenic fuel storage facility at the Space Station. An alternative to fuel storage onboard the Space Station, is on a tethered orbital refueling facility (TORF) which is separated from the Space Station by a sufficient distance to induce a gravity gradient to settle the propellants. Facility operations are a major concern associated with a tethered LO2/LH2 storage depot. A study was carried out to analyze these operations so as to identify the preferred TORF deployment direction (up or down) and whether the TORF should be permanently or intermittently deployed. The analyses considered safety, contamination, rendezvous, servicing, transportation rate, communication, and viewing. An upwardly, intermittently deployed facility is the preferred configuration for a tethered cryogenic fuel storage.

[Morbidity with temporary disability in railway tunnel workers].

PubMed

Kudrin, V A; Prokhorov, A A

2003-01-01

The paper presents data on the health status of a large professional group of transport building workers--those who build BAM railway tunnels and those who build Moscow and Saint Petersburg underground stations. Major factors that are associated with underground work and that form the level of morbidity with temporary disability are identified. Respiratory, osteomuscular, digestive diseases, accidents, intoxications, and injuries are predominant in the structure of temporary disability. Lines of better organization of therapeutical-and-prophylactic aid to this contingent are defined.

Infrastructure for collaborative science and societal applications in the Columbia River estuary

NASA Astrophysics Data System (ADS)

Baptista, António M.; Seaton, Charles; Wilkin, Michael P.; Riseman, Sarah F.; Needoba, Joseph A.; Maier, David; Turner, Paul J.; Kärnä, Tuomas; Lopez, Jesse E.; Herfort, Lydie; Megler, V. M.; McNeil, Craig; Crump, Byron C.; Peterson, Tawnya D.; Spitz, Yvette H.; Simon, Holly M.

2015-12-01

To meet societal needs, modern estuarine science needs to be interdisciplinary and collaborative, combine discovery with hypotheses testing, and be responsive to issues facing both regional and global stakeholders. Such an approach is best conducted with the benefit of data-rich environments, where information from sensors and models is openly accessible within convenient timeframes. Here, we introduce the operational infrastructure of one such data-rich environment, a collaboratory created to support (a) interdisciplinary research in the Columbia River estuary by the multi-institutional team of investigators of the Science and Technology Center for Coastal Margin Observation & Prediction and (b) the integration of scientific knowledge into regional decision making. Core components of the operational infrastructure are an observation network, a modeling system and a cyber-infrastructure, each of which is described. The observation network is anchored on an extensive array of long-term stations, many of them interdisciplinary, and is complemented by on-demand deployment of temporary stations and mobile platforms, often in coordinated field campaigns. The modeling system is based on finiteelement unstructured-grid codes and includes operational and process-oriented simulations of circulation, sediments and ecosystem processes. The flow of information is managed through a dedicated cyber-infrastructure, conversant with regional and national observing systems.

Crustal shear wave velocity structure in the northeastern Tibet based on the Neighbourhood algorithm inversion of receiver functions

NASA Astrophysics Data System (ADS)

Wu, Zhenbo; Xu, Tao; Liang, Chuntao; Wu, Chenglong; Liu, Zhiqiang

2018-03-01

The northeastern (NE) Tibet records and represents the far-field deformation response of the collision between the Indian and Eurasian plates in the Cenozoic time. Over the past two decades, studies have revealed the existence of thickened crust in the NE Tibet, but the thickening mechanism is still in debate. We deployed a passive-source seismic profile with 22 temporary broad-band seismic stations in the NE Tibet to investigate the crustal shear wave velocity structure in this region. We selected 288 teleseismic events located in the west Pacific subduction zone near Japan with similar ray path to calculate P-wave receiver functions. Neighbourhood algorithm method is applied to invert the shear wave velocity beneath stations. The inversion result shows a low-velocity zone (LVZ) is roughly confined to the Songpan-Ganzi block and Kunlun mountains and extends to the southern margin of Gonghe basin. Considering the low P-wave velocity revealed by the wide-angle reflection-refraction seismic experiment and high ratio of Vp/Vs based on H-κ grid searching of the receiver functions in this profile, LVZ may be attributed to partial melting induced by temperature change. This observation appears to be consistent with the crustal ductile deformation in this region derived from other geophysical investigations.

PC based temporary shielding administrative procedure (TSAP)

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

Olsen, D.E.; Pederson, G.E.; Hamby, P.N.

1995-03-01

A completely new Administrative Procedure for temporary shielding was developed for use at Commonwealth Edison`s six nuclear stations. This procedure promotes the use of shielding, and addresses industry requirements for the use and control of temporary shielding. The importance of an effective procedure has increased since more temporary shielding is being used as ALARA goals become more ambitious. To help implement the administrative procedure, a personal computer software program was written to incorporate the procedural requirements. This software incorporates the useability of a Windows graphical user interface with extensive help and database features. This combination of a comprehensive administrative proceduremore » and user friendly software promotes the effective use and management of temporary shielding while ensuring that industry requirements are met.« less

Investigation on earthquake ground motions observed along a north-south survey line in the Kumamoto Plain, during the aftershocks of 2016 Kumamoto earthquake

NASA Astrophysics Data System (ADS)

Tsuno, S.; Korenaga, M.; Okamoto, K.; Chimoto, K.; Yamanaka, H.; Yamada, N.; Matsushima, T.

2017-12-01

To evaluate local site effects in the Kumamoto Plain, we installed 15 temporary seismic stations along the north-south survey line, after the 2016 Kumamoto earthquake foreshock (Mj 6.4). In this report, to investigate earthquake ground motions observed along the north-south survey line, we estimated site amplification factors from weak ground motion data and estimated S-wave velocity structures by array microtremor observations at temporary seismic stations. We installed 15 temporary seismic stations at an interval of 300m to 2.5km along the north-south survey line. We estimated site amplification factors, with a station at Mt. Kinbo as a reference. Site amplification factors at the middle part and the southern part along the survey line, located in the alluvial lowland, were dominated in the frequency of 1-2Hz. On the other hand, site amplification factors at the northern part along the survey line were dominated in the frequency of 2-5Hz. It suggests that the ground profiles near the surface are complicate along this north-south survey line in the Kumamoto Plain. Therefore, we performed array microtremor observations at the temporary seismic stations, to estimate S-wave velocity structures along the north-south survey line. We obtained phase velocities of Rayleigh waves by the SPAC method and estimated S-wave velocity structures by applying the Genetic Algorism to those phase velocity. The low velocity layer with a thickness of around 15m was deposited on the surface at sites located in the alluvial lowland. Finally, we compared the distribution of PGAs observed along the north-south survey line to AVs30 estimated by S-wave velocity structures. As a result, PGAs along the survey line were strongly concerned by AVs30. We concluded that earthquake ground motions in the frequency of more than 1Hz observed in this north-south survey line were excited by the low velocity layer near the surface.

76 FR 55393 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-07

... temporary housing units deployed in the Gulf Coast region following hurricanes Katrina and Rita. The title... housing units following hurricanes Katrina and Rita, and who were potentially exposed to higher levels of...

Earthquake hypocenters and focal mechanisms in central Oklahoma reveal a complex system of reactivated subsurface strike-slip faulting

USGS Publications Warehouse

McNamara, Daniel E.; Benz, Harley M.; Herrmann, Robert B.; Bergman, Eric A.; Earle, Paul S.; Holland, Austin F.; Baldwin, Randy W.; Gassner, A.

2015-01-01

The sharp increase in seismicity over a broad region of central Oklahoma has raised concern regarding the source of the activity and its potential hazard to local communities and energy industry infrastructure. Since early 2010, numerous organizations have deployed temporary portable seismic stations in central Oklahoma in order to record the evolving seismicity. In this study, we apply a multiple-event relocation method to produce a catalog of 3,639 central Oklahoma earthquakes from late 2009 through 2014. RMT source parameters were determined for 195 of the largest and best-recorded earthquakes. Combining RMT results with relocated seismicity enabled us to determine the length, depth and style-of-faulting occurring on reactivated subsurface fault systems. Results show that the majority of earthquakes occur on near vertical, optimally oriented (NE-SW and NW-SE), strike-slip faults in the shallow crystalline basement. These are necessary first order observations required to assess the potential hazards of individual faults in Oklahoma.

78 FR 65636 - Combined Notice of Filings

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-01

...: RP14-70-000. Applicants: Rochester Gas and Electric Corporation, Allegany Generating Station LLC. Description: Joint Petition of Rochester Gas and Electric Corporation and Allegany Generating Station LLC for Temporary Waiver of Capacity Release Regulations and Policies, and Request for Expedited Treatment. Filed...

New Technology Changing The Face of Mobile Seismic Networks

NASA Astrophysics Data System (ADS)

Brisbourne, A.; Denton, P.; Seis-Uk

SEIS-UK, a seismic equipment pool and data management facility run by a consortium of four UK universities (Leicester, Leeds, Cambridge and Royal Holloway, London) completed its second phase in 2001. To compliment the existing broadband equipment pool, which has been deployed to full capacity to date, the consortium undertook a tender evaluation process for low-power, lightweight sensors and recorders, for use on both controlled source and passive seismic experiments. The preferred option, selected by the consortium, was the Guralp CMG-6TD system, with 150 systems ordered. The CMG-6TD system is a new concept in temporary seismic equipment. A 30s- 100Hz force-feedback sensor, integral 24bit digitiser and 3-4Gbyte of solid-state memory are all housed in a single unit. Use of the most recent technologies has kept the power consumption to below 1W and the weight to 3.5Kg per unit. The concept of the disk-swap procedure for obtaining data from the field has been usurped by a fast data download technique using firewire technology. This allows for rapid station servicing, essential when 150 stations are in use, and also ensures the environmental integrity of the system by removing the requirement for a disk access port and envi- ronmentally exposed data disk. The system therefore meets the criteria for controlled source and passive seismic experiments: (1) the single unit concept and low-weight is designed for rapid deployment on short-term projects; (2) the low power consumption reduces the power-supply requirements facilitating deployment; (3) the low self-noise and bandwidth of the sensor make it applicable to passive experiments involving nat- ural sources. Further to this acquisition process, in collaboration with external groups, the SEIS- UK data management procedures have been streamlined with the integration of the Guralp GCF format data into the PASSCAL PDB software. This allows for rapid dissemination of field data and the production of archive-ready datasets, reducing the time between field recording and data archive. The archiving procedure for SEIS- UK datasets has been established, with data from experiments carried out with the broadband equipment already on the permanent continuous data archive at IRIS DMC.

Upper mantle structure beneath the northern part of the East African Plateau using data from the NE Uganda temporary seismic network

NASA Astrophysics Data System (ADS)

Bressers, C. A.; Nyblade, A.; Tugume, F.

2017-12-01

Data from a newly installed temporary seismic array in northeastern Uganda are incorporated into an existing body wave tomography model of eastern Africa to improve imaging of the upper mantle beneath the northern part of the East African Plateau. Nine temporary broadband stations were installed in January 2017 and will be operated through 2018 to obtain data for resolving structure under the northern part of the plateau as well as the East African rift in northern Kenya. Preliminary tomography models incorporate several months of data from stations in NE Uganda, plus many years of data from over 200 seismic stations throughout eastern Africa used in previously published body wave tomography models. The data come from teleseismic earthquakes with mb ≥ 5.5 at a distance from each station of 30° to 90°. P and S wave travel time residuals have been obtained using a multichannel cross correlation method and inverted using VanDecar's method to produce 3D tomographic images of the upper mantle. The preliminary results exhibit better resolved structure under the northern part of the East African Plateau than pervious models and suggest that the fast-wave speed anomaly in the upper mantle associated with the Tanzanian Craton—which is bounded by the Western and Eastern branches of the rift system—extends across most of northern Uganda.

Seismic Noise Analysis and Reduction through Utilization of Collocated Seismic and Atmospheric Sensors at the GRO Chile Seismic Network

NASA Astrophysics Data System (ADS)

Farrell, M. E.; Russo, R. M.

2013-12-01

The installation of Earthscope Transportable Array-style geophysical observatories in Chile expands open data seismic recording capabilities in the southern hemisphere by nearly 30%, and has nearly tripled the number of seismic stations providing freely-available data in southern South America. Through the use of collocated seismic and atmospheric sensors at these stations we are able to analyze how local atmospheric conditions generate seismic noise, which can degrade data in seismic frequency bands at stations in the ';roaring forties' (S latitudes). Seismic vaults that are climate-controlled and insulated from the local environment are now employed throughout the world in an attempt to isolate seismometers from as many noise sources as possible. However, this is an expensive solution that is neither practical nor possible for all seismic deployments; and also, the increasing number and scope of temporary seismic deployments has resulted in the collection and archiving of terabytes of seismic data that is affected to some degree by natural seismic noise sources such as wind and atmospheric pressure changes. Changing air pressure can result in a depression and subsequent rebound of Earth's surface - which generates low frequency noise in seismic frequency bands - and even moderate winds can apply enough force to ground-coupled structures or to the surface above the seismometers themselves, resulting in significant noise. The 10 stations of the permanent Geophysical Reporting Observatories (GRO Chile), jointly installed during 2011-12 by IRIS and the Chilean Servicio Sismológico, include instrumentation in addition to the standard three seismic components. These stations, spaced approximately 300 km apart along the length of the country, continuously record a variety of atmospheric data including infrasound, air pressure, wind speed, and wind direction. The collocated seismic and atmospheric sensors at each station allow us to analyze both datasets together, to gain insight into how local atmospheric conditions couple with the ground to generate seismic noise, and to explore strategies for reducing this noise post data collection. Comparison of spectra of atmospheric data streams to the three broadband seismic channels for continuous signals recorded during May and June of 2013 shows high coherence between infrasound signals and time variation of air pressure (dP/dt) that we calculated from the air pressure data stream. Coherence between these signals is greatest for the east-west component of the seismic data in northern Chile. Although coherence between seismic, infrasound, and dP/dt is lower for all three seismic channels at other GRO Chile stations, for some of the data streams coherence can jump as much as 6 fold for certain frequency bands, with a common 3-fold increase for periods shorter than 10 seconds and the occasional 6-fold increase at long or very long periods.

Constraints on recent earthquake source parameters, fault geometry and aftershock characteristics in Oklahoma

NASA Astrophysics Data System (ADS)

McNamara, D. E.; Benz, H.; Herrmann, R. B.; Bergman, E. A.; McMahon, N. D.; Aster, R. C.

2014-12-01

In late 2009, the seismicity of Oklahoma increased dramatically. The largest of these earthquakes was a series of three damaging events (Mw 4.8, 5.6, 4.8) that occurred over a span of four days in November 2011 near the town of Prague in central Oklahoma. Studies suggest that these earthquakes were induced by reactivation of the Wilzetta fault due to the disposal of waste water from hydraulic fracturing ("fracking") and other oil and gas activities. The Wilzetta fault is a northeast trending vertical strike-slip fault that is a well known structural trap for oil and gas. Since the November 2011 Prague sequence, thousands of small to moderate (M2-M4) earthquakes have occurred throughout central Oklahoma. The most active regions are located near the towns of Stillwater and Medford in north-central Oklahoma, and Guthrie, Langston and Jones near Oklahoma City. The USGS, in collaboration with the Oklahoma Geological Survey and the University of Oklahoma, has responded by deploying numerous temporary seismic stations in the region in order to record the vigorous aftershock sequences. In this study we use data from the temporary seismic stations to re-locate all Oklahoma earthquakes in the USGS National Earthquake Information Center catalog using a multiple-event approach known as hypo-centroidal decomposition that locates earthquakes with decreased uncertainty relative to one another. Modeling from this study allows us to constrain the detailed geometry of the reactivated faults, as well as source parameters (focal mechanisms, stress drop, rupture length) for the larger earthquakes. Preliminary results from the November 2011 Prague sequence suggest that subsurface rupture lengths of the largest earthquakes are anomalously long with very low stress drop. We also observe very high Q (~1000 at 1 Hz) that explains the large felt areas and we find relatively low b-value and a rapid decay of aftershocks.

76 FR 18395 - Safety Zone; Naval Air Station Corpus Christi Air Show, Oso Bay, Corpus Christi, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

...-AA00 Safety Zone; Naval Air Station Corpus Christi Air Show, Oso Bay, Corpus Christi, TX AGENCY: Coast... zone on the navigable waters of Oso Bay in Corpus Christi, Texas in support of the 2011 Naval Air Station Corpus Christi Air Show. This temporary safety zone is necessary to provide for the safety of...

Microseismic Properties of Typhoons in the Western Pacific

NASA Astrophysics Data System (ADS)

Xu, Y.; Koper, K. D.; Burlacu, R.

2017-12-01

We analyzed the ambient seismic noise recorded in 2012 by a temporary array of 240 seismometers deployed in Yunnan, China as part of Phase I of the ChinArray project. The stations were installed with a quasi-uniform spacing of about 70 km by the Yunnan Earthquake Administration. Each station consisted of a three-component Guralp-3ESP seismometer and a Reftek 130 data acquisition system with a sampling interval of 0.01 s. To identify the structure and source of the ambient noise, we applied frequency-dependent polarization analysis to the individual stations and f-k analysis for three sub-arrays consisting of 14-25 stations. The most prominent microseismic signals we observed were surface waves generated at periods of 3-7 s by 15 typhoons that occurred in the Western Pacific, mostly during the summer of 2012. The U.S. Navy's Joint Typhoon Warning Center divides a tropical cyclone into four levels, Tropical Depression (TD), Tropical Storm (TS), Typhoon (TY) and Super Typhoon (ST) based on the estimated wind speed. Four of the 15 analyzed typhoons reached ST intensity. The maximum microseism signals tended to last throughout the lifetime of a typhoon. Sometimes, we observed the splitting of a single microseism spectral peak into two parallel peaks. We compared the seismic observations to storm track data for typhoons Guchol, Jelawat, and Son-Tinh, and with oceanic models of wave-wave interaction. We find that microseismic power is correlated with changes in the direction or speed, or both, of the typhoon track. High wind speed or changing wind speed within the typhoon does not have a clear relationship with the microseismic power.

Seismic-monitoring changes and the remote deployment of seismic stations (seismic spider) at Mount St. Helens, 2004-2005: Chapter 7 in A volcano rekindled: the renewed eruption of Mount St. Helens, 2004-2006

USGS Publications Warehouse

McChesney, Patrick J.; Couchman, Marvin R.; Moran, Seth C.; Lockhart, Andrew B.; Swinford, Kelly J.; LaHusen, Richard G.; Sherrod, David R.; Scott, William E.; Stauffer, Peter H.

2008-01-01

The instruments in place at the start of volcanic unrest at Mount St. Helens in 2004 were inadequate to record the large earthquakes and monitor the explosions that occurred as the eruption developed. To remedy this, new instruments were deployed and the short-period seismic network was modified. A new method of establishing near-field seismic monitoring was developed, using remote deployment by helicopter. The remotely deployed seismic sensor was a piezoelectric accelerometer mounted on a surface-coupled platform. Remote deployment enabled placement of stations within 250 m of the active vent.

Whitson in her TeSS in the Destiny U.S. Lab during STS-111 UF-2 docked OPS

NASA Image and Video Library

2002-06-09

STS111-E-5122 (9 June 2002) --- Astronaut Peggy A. Whitson, Expedition Five flight engineer, was photographed in the doorway of the Temporary Sleep Station (TSS) in the Destiny laboratory on International Space Station (ISS).

Cascadia Initiative Reveals Accumulation of Buoyant Material Beneath the Subducting Juan de Fuca Plate

NASA Astrophysics Data System (ADS)

Hawley, W. B.; Allen, R. M.; Richards, M. A.

2015-12-01

The Cascadia Initiative is a four-year (2011-2015) amphibious seismic deployment that covers the Juan de Fuca plate and the Cascadia Subduction Zone. It is comprised of 70 broadband ocean-bottom seismometers that occupy 120 sites in total, as well as 27 land-based stations. This array offers a unique opportunity to study the 3D structure of a subduction zone in unprecedented detail. We present the results of an inversion using teleseismic body waves recorded by the Cascadia Initiative, EarthScope, and other regional and temporary networks in the Pacific Northwest. A low-velocity feature is visible beneath the subducting slab at shallow depths. Previous studies report ponding of low-viscosity, buoyant material at the top of the asthenosphere, unable to rise through the impermeable lithospheric lid. We show that as the lithospheric lid descends into the mantle, this material is not advected with it; rather, due to its own weakness and buoyancy, it accumulates at the subduction zone. Such material could be partly responsible for the rapid uplift and volcanism in the Coast Range of California, in the wake of the northward migration of the Mendocino Triple Junction. This newly observed feature may play an important role in the structure of subduction zones, but understanding the extent of that role on a global scale will require amphibious seismic deployments in other subduction zones.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-045009 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing. Station solar array panels, Earth's horizon and the blackness of space provide the backdrop for the scene.

Broadband Array Analysis of the 2005 Episodic Tremor and Slip Event in Northern Cascadia

NASA Astrophysics Data System (ADS)

Wech, A.; Creager, K.; McCausland, W.; Frassetto, A.; Qamar, A.; Derosier, S.; Carmichael, J.; Malone, S.; Johnson, D.

2005-12-01

The region of Cascadia from the Olympic Mountains through southern Vancouver Island and down-dip of the subduction megathrust has repeatedly experienced episodes of slow slip. This episodic slip, which has been observed to take place over a period of two to several weeks, is accompanied by a seismic tremor signal. Based on the average recurrence interval of 14 months, the next episodic tremor and slip (ETS) event should occur within six weeks of mid-September, 2005. Indeed, it appears to have begun on September 3, as this abstract was being written. In order to record this anticipated event, we deployed an array of 11 three-component seismometers on the northern side of the Olympic Peninsula augmenting Pacific Northwest Seismographic Network stations as well as the first few EarthScope BigFoot stations and Plate Boundary Observatory borehole seismometers. This seismic array was comprised of six short-period and five broadband instruments with spacings of 500 m and 2200 m respectively. In conjunction with this Earthscope seismic deployment, we also installed a dense network of 29 temporary, continuous GPS stations across the entire Olympic Peninsula to integrate seismic and geodetic observations. One of the primary goals of this research is to utilize the broadband instrumentation in the array to investigate the possible correlation of low frequency energy with the rest of the tremor activity. ETS has been carefully investigated at high-frequency (seismic tremor at 2-6 Hz) and very low-frequency (slip occurring over weeks, observed by GPS). An important goal of this experiment is to investigate the possibility that the tremor generates intermediate, low-frequency signals. Preliminary analysis of short-period array recordings of the July, 2004 ETS event suggests that the tremor displays signs of lower-frequency energy (~0.5 Hz) correlated with its higher frequency activity. Our array should enable us to distinguish low- frequency signals originating in the direction of high-frequency tremor from noise in other directions. We will present an analysis of the low-frequency energy associated with this slip event.

Comparative thermal analysis of the Space Station Freedom photovoltaic deployable boom structure using TRASYS, NEVADA, and SINDA programs

NASA Technical Reports Server (NTRS)

Baumeister, Joseph F.; Beach, Duane E.; Armand, Sasan C.

1989-01-01

The proposed Space Station Photovoltaic Deployable Boom was analyzed for operating temperatures. The boom glass/epoxy structure design needs protective shielding from environmental degradation. The protective shielding optical properties (solar absorptivity and emissivity) dictate the operating temperatures of the boom components. The Space Station Boom protective shielding must also withstand the effects of the extendible/retractable coiling acting within the mast canister. A thermal analysis method was developed for the Space Station Deployable Boom to predict transient temperatures for a variety of surface properties. The modeling procedures used to evaluate temperatures within the boom structure incorporated the TRASYS, NEVADA, and SINDA thermal analysis programs. Use of these programs led to a comparison between TRASYS and NEVADA analysis methods. Comparing TRASYS and NEVADA results exposed differences in the environmental solar flux predictions.

Comparative thermal analysis of the space station Freedom photovoltaic deployable boom structure using TRASYS, NEVADA, and SINDA programs

NASA Technical Reports Server (NTRS)

Baumeister, Joseph F.; Beach, Duane E.; Armand, Sasan C.

1989-01-01

The proposed Space Station Photovoltaic Deployable Boom was analyzed for operating temperatures. The boom glass/epoxy structure design needs protective shielding from environmental degradation. The protective shielding optical properties (solar absorptivity and emissivity) dictate the operating temperatures of the boom components. The Space Station Boom protective shielding must also withstand the effects of the extendible/retractable coiling action within the mast canister. A thermal analysis method was developed for the Space Station Deployable Boom to predict transient temperatures for a variety of surface properties. The modeling procedures used to evaluate temperatures within the boom structure incorporated the TRASYS, NEVADA, and SINDA thermal analysis programs. Use of these programs led to a comparison between TRASYS and NEVADA analysis methods. Comparing TRASYS and NEVADA results exposed differences in the environmental solar flux predictions.

The X-beam as a deployable boom for the space station

NASA Technical Reports Server (NTRS)

Adams, Louis R.

1988-01-01

Extension of antennas and thrust modules from the primary structure of the space station will require deployable beams of high stiffness and strength, as well as low mass and package volume. A square boom cross section is desirable for interface reasons. These requirements and others are satisfied by the X-beam. The X-beam folds by simple geometry, using single-degree-of-freedom hinges at simple angles, with no strain during deployment. Strut members are of large diameter with unidirectional graphite fibers for maximum beam performance. Fittings are aluminum with phosphor bronze bushings so that compliance is low and joint lifetime is high. The several beam types required for different applications on the space station will use the same basic design, with changes in strut cross section where necessary. Deployment is by a BI-STEM which pushes the beam out; retraction is by cables which cause initial folding and pull the beam in.

New constraints on micro-seismicity and stress state in the western part of the North Anatolian Fault Zone: Observations from a dense seismic array

NASA Astrophysics Data System (ADS)

Altuncu Poyraz, Selda; Teoman, M. Uğur; Türkelli, Niyazi; Kahraman, Metin; Cambaz, Didem; Mutlu, Ahu; Rost, Sebastian; Houseman, Gregory A.; Thompson, David A.; Cornwell, David; Utkucu, Murat; Gülen, Levent

2015-08-01

With the aim of extensively investigating the crustal structure beneath the western segment of the North Anatolian Fault Zone where it splays into northern and southern branches, a temporary seismic network (dense array for North Anatolia-DANA) consisting of 70 stations was deployed in early May 2012 and operated for 18 months in the Sakarya region during the FaultLab experiment. Out of 2437 events contaminated by explosions, we extracted 1371 well located earthquakes. The enhanced station coverage having a nominal station spacing of 7 km, lead to a minimum magnitude calculation of 0.1. Horizontal and vertical location uncertainties within the array do not exceed 0.8 km and 0.9 km, respectively. We observe considerable seismic activity along both branches of the fault where the depth of the seismogenic zone was mostly confined to 15 km. Using our current earthquake catalog we obtained a b-value of 1. We also mapped the b-value variation with depth and observed a gradual decrease. Furthermore, we determined the source parameters of 41 earthquakes with magnitudes greater than 1.8 using P-wave first motion polarity method. Regional Moment Tensor Inversion method was also applied to earthquakes with magnitudes greater than 3.0. Focal mechanism solutions confirm that Sakarya and its vicinity is stressed by a compressional regime showing a primarily oblique-slip motion character. Stress tensor analysis indicates that the maximum principal stress is aligned in WNW-ESE direction and the tensional axis is aligned in NNE-SSW direction.

Crustal Structure in the Western Part of Romania from Local Seismic Tomography

NASA Astrophysics Data System (ADS)

Zaharia, Bogdan; Grecu, Bogdan; Popa, Mihaela; Oros, Eugen; Radulian, Mircea

2017-12-01

The inner part of the Carpathians in Romania belongs to the Carpathians-Pannonian system bordered by the Eastern Carpathians to the north and east, Southern Carpathians to the south and Pannonian Basin to the west. It is a complex tectonic region with differential folding mechanisms, post-collisional kinematics, rheology and thermal properties, including within its area the Apuseni Mountains and the Transylvanian Basin. The purpose of this study is to map the 3-D structure of the crust over this region on the basis of local earthquake data. Input data were recorded during the South Carpathian Project (2009-2011), a successful collaboration between the Institute of Geophysics and Tectonics of the University of Leeds and the National Institute for Earth Physics (NIEP), Romania. A temporary array of 32 broadband seismic stations (10 CMG-40T, 8 CMG-3T and 14 CMG-6TD) was installed across the western part of Romania (spaced at 40 to 50 km intervals) during the project. In addition, 25 stations deployed in the eastern Hungary and Serbia was considered. P- and S-wave arrivals are identified for all the selected events (minimum 7 phases per event with reasonable signal/noise ratio). All the events are first relocated using Joint Hypocentre Determination (JHD) technique. Then the well-located events were inverted to determine the crustal structure using LOTOS algorithm. The lateral variations of the crustal properties as resulted from the tomography image are interpreted in correlation with the station corrections estimated by JHD algorithm and with the post-collisional evolution of the Carpathians-Pannonian system.

Nanoracks CUBESAT launcher

NASA Image and Video Library

2014-08-19

ISS040-E-103506 (19 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer is about to release a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. The station?s Kibo laboratory is at top right. A blue and white part of Earth and the blackness of space provide the backdrop for the scene.

Evaluation of the new infrastructure for French Permanent Broadband Stations in Auvergne (France).

NASA Astrophysics Data System (ADS)

Douchain, J. M.; Regis, E.; Battaglia, J.; Vergne, J.

2017-12-01

French seismologic and geodetic network (RESIF) is a national equipment for the observation and understanding of the solid Earth. It is an instrument aimed at acquiring new top-quality data for disciplines like seismology, geodesy and gravimetry to advance the understanding of the dynamics of our planet. The seismology component of RESIF, with its homogeneous coverage of the territory, will allow better localisation and characterisation of seismic activityover a wide range of magnitudes as well as provide high quality data for research The Auvergne Seismic Network (ASN) manages seismic stations in the center of france since the beginning of the 80's and continuously ugrades them. Nowadays, 21 stations (velocimeters and accelerometers) are deployed to monitor the Massif Central seismic activity. In the future, the ASN will run 15 broadband stations that will be part of RESIF network. Six of theses sites already have former generation instrumentation (short period sensors buried in the ground, low dynamic) but others are completely new. In june 2017, 4 permanent seismic stations have been upgraded to the new standard installation type for open environment. The chozen infrastructure is a 5 meter drilling equiped with a posthole broadband sensor. Prior to these final installations, on each site, Trillium 120 PA have been installed for 2 temporary experiments. The first one consisted of a direct burial installations at about 80 centimeters depth and lasted for 1 or 2 months. The second dataset was recorded in shallow seismic vaults, during 6 months.In this study, we compare, for each site, data recorded with the 3 configurations in order to evaluate the profits of the new RESIF installations. For this purpose, we compare the probability density fonctions to evaluate noise levels, as well as sprectrograms and hourly detection number. Our results show that the installation of sensors in drillings greatly improves the quality of data at low and high frequencies.

Repeat Absolute and Relative Gravity Measurements for Geothermal Reservoir Monitoring in the Ogiri Geothermal Field, Southern Kyushu, Japan

NASA Astrophysics Data System (ADS)

Nishijima, J.; Umeda, C.; Fujimitsu, Y.; Takayama, J.; Hiraga, N.; Higuchi, S.

2016-09-01

Repeat hybrid microgravity measurements were conducted around the Ogiri Geothermal Field on the western slope of Kirishima volcano, southern Kyushu, Japan. This study was undertaken to detect the short-term gravity change caused by the temporary shutdown of production and reinjection wells for regular maintenance in 2011 and 2013. Repeat microgravity measurements were taken using an A-10 absolute gravimeter (Micro-g LaCoste) and CG-5 gravimeter (Scintrex) before and after regular maintenance. Both instruments had an accuracy of 10 μgal. The gravity stations were established at 27 stations (two stations for absolute measurements and 25 stations for relative measurements). After removal of noise effects (e.g., tidal movement, precipitation, shallow groundwater level changes), the residual gravity changes were subdivided into five types of response. We detected a gravity decrease (up to 20 μgal) in the reinjection area and a gravity increase (up to 30 μgal) in the production area 1 month after the temporary shutdown. Most of the gravity stations recovered after the maintenance. The temporal density changes in the geothermal reservoir were estimated based on these gravity changes.

Moho depth across the Trans-European Suture Zone from ambient vibration autocorrelations

NASA Astrophysics Data System (ADS)

Becker, Gesa; Knapmeyer-Endrun, Brigitte

2017-04-01

In 2018 the InSight mission to Mars will deploy a seismic station on the planet. This seismic station will consist of a three-component very broadband seismic sensor and a collocated three-component short period seismometer. Single station methods are therefore needed to extract information from the data and learn more about the interior structure of Mars. One potential method is the extraction of reflected phases from autocorrelations. Here autocorrelations are derived from ambient seismic noise to make the most of the data expected, as seismicity on Mars is likely less abundant than on Earth. These autocorrelations are calculated using a phase autocorrelation algorithm and time-frequency domain phase-weighted stacking as the main processing steps in addition to smoothing the spectrum of the data with a short term-long term average algorithm. Afterward the obtained results are filtered and analyzed in the frequency range of 1-2 Hz. The developed processing scheme is applied to data from permanent seismic stations located in different geological provinces across Europe, i.e. the Upper Rhine Graben, Central European Platform, Bohemian Massif, Northern German and Polish Basin, and the East European Craton, with varying Moho depths between 25-50 km. These crustal thicknesses are comparable to various estimates for Mars, therefore providing a good reference and indication of resolvability for Moho depths that might be encountered at the landing site. Changes in reflectivity can be observed in the calculated autocorrelations. The lag times of these changes are converted into depths with the help of available velocity information (EPcrust and local models for Poland and the Czech Republic, respectively) and the results are compared to existing information on Moho depths, which show good agreement. The results are temporarily stable, but show a clear correlation with the existence of cultural noise. Based on the closely located broadband and short period stations of the GERESS-array, it is shown that the processing scheme is also applicable to short period stations. Subsequently it is applied to the mainly short period and temporary stations of the PASSEQ network along the seismic profile POLONAISE P4, running from Eastern Germany to Lithuania crossing the Trans-European Suture Zone.

Technology and Engineering Advances Supporting EarthScope's Alaska Transportable Array

NASA Astrophysics Data System (ADS)

Miner, J.; Enders, M.; Busby, R.

2015-12-01

EarthScope's Transportable Array (TA) in Alaska and Canada is an ongoing deployment of 261 high quality broadband seismographs. The Alaska TA is the continuation of the rolling TA/USArray deployment of 400 broadband seismographs in the lower 48 contiguous states and builds on the success of the TA project there. The TA in Alaska and Canada is operated by the IRIS Consortium on behalf of the National Science Foundation as part of the EarthScope program. By Sept 2015, it is anticipated that the TA network in Alaska and Canada will be operating 105 stations. During the summer of 2015, TA field crews comprised of IRIS and HTSI station specialists, as well as representatives from our partner agencies the Alaska Earthquake Center and the Alaska Volcano Observatory and engineers from the UNAVCO Plate Boundary Observatory will have completed a total of 36 new station installations. Additionally, we will have completed upgrades at 9 existing Alaska Earthquake Center stations with borehole seismometers and the adoption of an additional 35 existing stations. Continued development of battery systems using LiFePO4 chemistries, integration of BGAN, Iridium, Cellular and VSAT technologies for real time data transfer, and modifications to electronic systems are a driving force for year two of the Alaska Transportable Array. Station deployment utilizes custom heliportable drills for sensor emplacement in remote regions. The autonomous station design evolution include hardening the sites for Arctic, sub-Arctic and Alpine conditions as well as the integration of rechargeable Lithium Iron Phosphate batteries with traditional AGM batteries We will present new design aspects, outcomes, and lessons learned from past and ongoing deployments, as well as efforts to integrate TA stations with other existing networks in Alaska including the Plate Boundary Observatory and the Alaska Volcano Observatory.

Validating alternative methodologies to estimate the regime of temporary rivers when flow data are unavailable.

PubMed

Gallart, F; Llorens, P; Latron, J; Cid, N; Rieradevall, M; Prat, N

2016-09-15

Hydrological data for assessing the regime of temporary rivers are often non-existent or scarce. The scarcity of flow data makes impossible to characterize the hydrological regime of temporary streams and, in consequence, to select the correct periods and methods to determine their ecological status. This is why the TREHS software is being developed, in the framework of the LIFE Trivers project. It will help managers to implement adequately the European Water Framework Directive in this kind of water body. TREHS, using the methodology described in Gallart et al. (2012), defines six transient 'aquatic states', based on hydrological conditions representing different mesohabitats, for a given reach at a particular moment. Because of its qualitative nature, this approach allows using alternative methodologies to assess the regime of temporary rivers when there are no observed flow data. These methods, based on interviews and high-resolution aerial photographs, were tested for estimating the aquatic regime of temporary rivers. All the gauging stations (13) belonging to the Catalan Internal Catchments (NE Spain) with recurrent zero-flow periods were selected to validate this methodology. On the one hand, non-structured interviews were conducted with inhabitants of villages near the gauging stations. On the other hand, the historical series of available orthophotographs were examined. Flow records measured at the gauging stations were used to validate the alternative methods. Flow permanence in the reaches was estimated reasonably by the interviews and adequately by aerial photographs, when compared with the values estimated using daily flows. The degree of seasonality was assessed only roughly by the interviews. The recurrence of disconnected pools was not detected by flow records but was estimated with some divergences by the two methods. The combination of the two alternative methods allows substituting or complementing flow records, to be updated in the future through monitoring by professionals and citizens. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of the Effects of Temporary Covered Nitinol Stent Placement in the Prostatic Urethra: Short-Term Study in the Canine Model

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

Crisostomo, Veronica; Song, Ho Young; Maynar, Manuel

Purpose. To evaluate the effect of temporary stent placement on the canine prostatic urethra. Methods. Retrievable PTFE-covered nitinol stents were placed in the prostatic urethras of 8 beagle dogs under fluoroscopic guidance. Retrograde urethrography was obtained before and after stenting. Retrograde urethrography and endoscopy were performed 1 and 2 months after deployment. The endoscopic degree of hyperplasia was rated on a scale of 0 to 4 (0 absence, 4 = occlusion). On day 60, stents were removed and urethrography was performed immediately before euthanasia. Pathologic analysis was performed to determine the degree of glandular atrophy, periurethral fibrosis, and urethral dilation.more » Results. Stent deployment was technically successful in 7 animals, and failed in 1 dog due to a narrow urethral lumen. Complete migration was seen in 2 animals at 1 month, and an additional stent was deployed. On day 30, endoscopy showed slight hyperplasia (grade 1) in 3 animals. On day 60, moderate hyperplasia (grade 2) was evidenced in 4 cases. No impairment of urinary flow was seen during follow-up. Retrieval was technically easy to perform, and was successful in all dogs. The major histologic findings were chronic inflammatory cell infiltrates; prostate glandular atrophy, with a mean value of 1.86 (SD 0.90); periurethral fibrosis, with a mean ratio of 29.37 (SD 10.41); and dilatation of the prostatic urethra, with a mean ratio of 6.75 (SD 3.22). Conclusion. Temporary prostatic stent placement in dogs is safe and feasible, causing marked enlargement of the prostatic urethral lumen. Retrievable covered stents may therefore be an option for bladder outlet obstruction management in men.« less

Deployable Mini-Payload Missions Enabled by Small Radioisotope Power Systems (RPSs)

NASA Technical Reports Server (NTRS)

Abelson, Robert D.; Satter, Celeste M.

2005-01-01

Deployable mini-payloads are envisioned as small, simple, standalone instruments that could be deployed from a mother vehicle such as a rover or the proposed Jupiter Icy Moons Orbiter to key points of interest within the solar system. Used in conjunction with a small radioisotope power system (RPS), these payloads could potentially be used for long-duration science missions or as positional beacons for rovers or other spacecraft. The RPS power source would be suitable for deployable mini-payload missions that would take place anywhere there is limited, intermittent, or no solar insolation. This paper introduces two such concepts: (1) a seismic monitoring station deployed by a rover or aerobot, and (2) a passive fields and particles station delivered by a mother spacecraft to Jupiter.

Small Cube Satellite Deploy

NASA Image and Video Library

2013-11-19

ISS038-E-003876 (19 Nov. 2013) --- Three nanosatellites, known as Cubesats, are featured in this image photographed by an Expedition 38 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module's robotic arm on Nov. 19, 2013. Japan Aerospace Exploration Agency astronaut Koichi Wakata, flight engineer, monitored the satellite deployment while operating the Japanese robotic arm from inside Kibo. The Cubesats were delivered to the International Space Station Aug. 9, aboard Japan’s fourth H-II Transfer Vehicle, Kounotori-4.

47 CFR 5.61 - Procedure for obtaining a special temporary authorization.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Office of Engineering and Technology Web site https://gullfoss2.fcc.gov/prod/oet/cf/els/index.cfm effective January 1, 2004 and shall contain the following information: (1) Name, address, phone number (also... proposed operation. (5) Class(es) of station (fixed, mobile, fixed and mobile) and call sign of station (if...

EMERGENCY COLLECTION SYSTEM FOR SPILLED HAZARDOUS MATERIALS

EPA Science Inventory

A prepackaged pumping and storage system for the collection and temporary containment of hazardous land spills was designed and two models developed. Each model includes a pump, hoses, furled self-deploying 26,500 l (7000 gal) capacity plastic bag array all mounted on a pallet fo...

Continent-arc collision in the Banda Arc imaged by ambient noise tomography

NASA Astrophysics Data System (ADS)

Porritt, Robert W.; Miller, Meghan S.; O'Driscoll, Leland J.; Harris, Cooper W.; Roosmawati, Nova; Teofilo da Costa, Luis

2016-09-01

The tectonic configuration of the Banda region in southeast Asia captures the spatial transition from subduction of Indian Ocean lithosphere to subduction and collision of the Australian continental lithosphere beneath the Banda Arc. An ongoing broadband seismic deployment funded by NSF is aimed at better understanding the mantle and lithospheric structure in the region and the relationship of the arc-continent collision to orogenesis. Here, we present results from ambient noise tomography in the region utilizing this temporary deployment of 30 broadband instruments and 39 permanent stations in Indonesia, Timor Leste, and Australia. We measure dispersion curves for over 21,000 inter-station paths resulting in good recovery of the velocity structure of the crust and upper mantle beneath the Savu Sea, Timor Leste, and the Nusa Tenggara Timur (NTT) region of Indonesia. The resulting three dimensional model indicates up to ∼25% variation in shear velocity throughout the plate boundary region; first-order velocity anomalies are associated with the subducting oceanic lithosphere, subducted Australian continental lithosphere, obducted oceanic sediments forming the core of the island of Timor, and high velocity anomalies in the Savu Sea and Sumba. The structure in Sumba and the Savu Sea is consistent with an uplifting forearc sliver. Beneath the island of Timor, we confirm earlier inferences of pervasive crustal duplexing from surface mapping, and establish a link to underlying structural features in the lowermost crust and uppermost mantle that drive upper crustal shortening. Finally, our images of the volcanic arc under Flores, Wetar, and Alor show high velocity structures of the Banda Terrane, but also a clear low velocity anomaly at the transition between subduction of oceanic and continental lithosphere. Given that the footprint of the Banda Terrane has previously been poorly defined, this model provides important constraints on tectonic reconstructions that formerly have lacked information on the lower crust and uppermost mantle.

The Southern Kansas Seismic Network

NASA Astrophysics Data System (ADS)

Terra, F. M.

2015-12-01

Historically aseismic Harper and Sumner counties in Southern Kansas experienced a dramatic increase in seismicity beginning in early 2014, coincident with the development of new oil production in the Mississippi Lime Play. In order to better understand the potential relationships between seismicity and oil development, the USGS installed a real-time telemetered seismic network in cooperation with the Kansas Geological Survey, the Kansas Corporation Commission, the Kansas Department of Health and Environment, Harper County, and the Oklahoma Geological Survey. The network began operation in March 2014 with an initial deployment of 5 NetQuakes accelerometers and by July 2014 had expanded to include 10 broadband sites. The network currently has 14 stations, all with accelerometers and 12 with broadband seismometers. The network has interstation spacing of 15 - 25 km and typical azimuthal gap of 80 for well-located events. Data are continuously streamed to IRIS at 200 samples per second from most sites. Earthquake locations are augmented with additional stations from the USGS National Network, Oklahoma Geological Survey Seismic Network, Kansas Seismic Monitoring Network and the Enid Oklahoma Network. Since the spring of 2014 over 7500 earthquakes have been identified with data from this network, 1400 of which have been manually timed and cataloged. Focal depths for earthquakes typically range between 2 and 7 km. The catalog is available at earthquake.usgs.gov/earthquakes/search/ under network code 'Ismpkansas'. The network recorded the largest known earthquake in Harper County, Mw 4.3, on October 2, 2014 and in Sumner County, Mw 4.9, on November 12, 2014. Recorded ground motions at the epicenter of the October earthquake were 0.70 g (PGA) and 12 cm/s (PGV). These high ground motion values agree with near-source recordings made by other USGS temporary deployments in the U. S. midcontinent, indicating a significant shaking hazard from such shallow, moderate-magnitude earthquakes.

Teleseismic P-wave tomography of the Sunda-Banda Arc subduction zone

NASA Astrophysics Data System (ADS)

Harris, C. W.; Miller, M. S.; Widiyantoro, S.; Supendi, P.; O'Driscoll, L.; Roosmawati, N.; Porritt, R.

2017-12-01

The Sunda-Banda Arc is the site of multiple ongoing tectonic deformation processes and is perhaps the best example of the transition from subduction of oceanic lithosphere to an active arc-continent collision. Investigating the mantle structure that has resulted from the collision of continental Australia, as well as the concurrent phenomena of continental subduction, slab-rollback, lithospheric tearing, and subduction polarity reversal is possible through seismic tomography. While both regional scale and global tomographic models have previously been constructed to study the tectonics this region, here we use 250 seismic stations that span the length of this convergent margin to invert for P-wave velocity perturbations in the upper mantle. We combine data from a temporary deployment of 30 broadband instruments as part of the NSF-funded Banda Arc Project, along with data from permanent broadband stations maintained by the Meteorological, Climatological, and Geophysical Agency of Indonesia (BMKG) to image mantle structure, in particular the subducted Indo-Australian plate. The BMKG dataset spans 2009-2017 and includes >200 broadband seismometers. The Banda Arc array (network YS) adds coverage and resolution to southeastern Indonesia and Timor-Leste, where few permanent seismometers are located but the Australian continent-Banda Arc collision is most advanced. The preliminary model was computed using 50,000 teleseismic P-wave travel-time residuals and 3D finite frequency sensitivity kernels. Results from the inversion of the combined dataset are presented as well as resolution tests to assess the quality of the model. The velocity model shows an arcuate Sunda-Banda slab with morphological changes along strike that correlate with the tectonic collision. The model also features the double-sided Molucca Sea slab and regions of high velocity below the bottom of the transition zone. The resolution added by the targeted USC deployment is clear when comparing models that use only BMKG data to models that incorporate the YS network as well.

47 CFR 74.833 - Temporary authorizations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... eligibility, facility identification number of the associated broadcast station (if any), type and... interest and importance which cannot be transmitted successfully on these frequencies, frequencies assigned...

Is the Isabella anomaly a fossil slab or the foundered lithospheric root of the Sierra Nevada batholith?

NASA Astrophysics Data System (ADS)

Hoots, C. R.; Schmandt, B.; Clayton, R. W.; Hansen, S. M.; Dougherty, S. L.

2015-12-01

The Isabella Anomaly is a volume of relatively high seismic velocity upper mantle beneath the southern Great Valley in California. We deployed ~45 broadband seismometers in central California to test two main hypotheses for the origin of the Isabella Anomaly. One suggests that the Isabella Anomaly is the foundered lithospheric root of the southern Sierra Nevada batholith, which delaminated on account of eclogite-rich composition and translated westward as it began to sink into the asthenosphere. The other hypothesis suggests that the Isabella Anomaly is a fossil slab fragment attached to the Monterey microplate that lies offshore of central California and thus it is mechanically coupled to the Pacific plate. Prior seismic imaging with ~70 km station spacing cannot resolve the landward termination of Monterey microplate lithosphere beneath coastal California or where/if the Isabella Anomaly is attached to North America lithosphere beneath the Great Valley. The new temporary broadband array consists of 40 broadband seismometers with ~7 km spacing extending from the central California coast to the western Sierra Nevada batholith, plus some outliers to fill gaps in the regional network coverage. The temporary array was initially deployed in early 2014 and will continue to record until October 2015 so the complete data are not yet available. Preliminary Ps scattered wave images show an abrupt ~6 km increase in Moho depth eastward across the San Andreas fault, a strong positive impedance contrast that dips westward from ~7-25 km beneath Great Valley, and a sharp Moho with a slight westward dip beneath the western edge of the Sierra Nevada batholith. Apparently low impedance contrast characterizes the Moho beneath the eastern Great Valley and foothills, consistent with near mantle velocities in the lower crust. Processing of the cumulative data that will be available in October 2015 and incorporation of new tomography models into scattered wave imaging are needed before assessing the significance of potential uppermost mantle interfaces that may represent edges of the Isabella Anomaly. Results from Ps and Sp scattered wave imaging, ambient noise surface wave tomography, teleseismic body-wave tomography, and teleseismic shear wave splitting will be presented.

47 CFR 74.433 - Temporary authorizations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... broadcast station must include full particulars including: licensee's name and address, facility... of events of wide-spread interest and importance which cannot be transmitted successfully on these...

Deployable-erectable trade study for space station truss structures

NASA Technical Reports Server (NTRS)

Mikulas, M. M., Jr.; Wright, A. S., Jr.; Bush, H. G.; Watson, J. J.; Dean, E. B.; Twigg, L. T.; Rhodes, M. D.; Cooper, P. A.; Dorsey, J. T.; Lake, M. S.

1985-01-01

The results of a trade study on truss structures for constructing the space station are presented. Although this study was conducted for the reference gravity gradient space station, the results are generally applicable to other configurations. The four truss approaches for constructing the space station considered in this paper were the 9 foot single fold deployable, the 15 foot erectable, the 10 foot double fold tetrahedral, and the 15 foot PACTRUSS. The primary rational for considering a 9 foot single-fold deployable truss (9 foot is the largest uncollapsed cross-section that will fit in the Shuttle cargo bay) is that of ease of initial on-orbit construction and preintegration of utility lines and subsystems. The primary rational for considering the 15 foot erectable truss is that the truss bay size will accommodate Shuttle size payloads and growth of the initial station in any dimension is a simple extension of the initial construction process. The primary rational for considering the double-fold 10 foot tetrahedral truss is that a relatively large amount of truss structure can be deployed from a single Shuttle flight to provide a large number of nodal attachments which present a pegboard for attaching a wide variety of payloads. The 15 foot double-fold PACTRUSS was developed to incorporate the best features of the erectable truss and the tetrahedral truss.

Stratus Ocean Reference Station (20 deg. S, 85 deg. W) : Mooring Recovery and Deployment Cruise, R/V Ronald H. Brown Cruise 05-05, September 26, 2005-October 21, 2005

DTIC Science & Technology

2006-02-01

WHOI- 2006 -06 Woods Hole Oceanographic Institution 1930 Stratus Ocean Reference Station (20°S, 85°W) Mooring Recovery and Deployment Cruise RN Ronald...Environmental Technology Laboratory, 3University of Colorado, CIRES, 4University of Miami, 5University of Concepcion February 2006 Technical Report...Institution Woods Hole, MA 02543 UOP Technical Report 2006 -01 WHOI- 2006 -06 UOP- 2006 -01 Stratus Ocean Reference Station (20*S, 85*W) Mooring Recovery and

Delta XTE Spacecraft Solar Panel Deployment, Hangar AO at Cape Canaveral Air Station

NASA Technical Reports Server (NTRS)

1995-01-01

The footage shows technicians in the clean room checking and adjusting the deployment mechanism of the solar panel for XTE spacecraft. Other scenes show several technicians making adjustments to software for deployment of the solar panels.

Database of multi-parametric geophysical data from the TOMO-DEC experiment on Deception Island, Antarctica.

PubMed

Ibáñez, Jesús M; Díaz-Moreno, Alejandro; Prudencio, Janire; Zandomeneghi, Daria; Wilcock, William; Barclay, Andrew; Almendros, Javier; Benítez, Carmen; García-Yeguas, Araceli; Alguacil, Gerardo

2017-09-12

Deception Island volcano (Antarctica) is one of the most closely monitored and studied volcanoes on the region. In January 2005, a multi-parametric international experiment was conducted that encompassed both Deception Island and its surrounding waters. We performed this experiment from aboard the Spanish oceanographic vessel 'Hespérides', and from five land-based locations on Deception Island (the Spanish scientific Antarctic base 'Gabriel de Castilla' and four temporary camps). This experiment allowed us to record active seismic signals using a large network of seismic stations that were deployed both on land and on the seafloor. In addition, other geophysical data were acquired, including bathymetric high precision multi-beam data, and gravimetric and magnetic profiles. To date, the seismic and bathymetric data have been analysed but the magnetic and gravimetric data have not. We provide P-wave arrival-time picks and seismic tomography results in velocity and attenuation. In this manuscript, we describe the main characteristics of the experiment, the instruments, the data, and the repositories from which data and information can be obtained.

Upper crustal structure of central Java, Indonesia, from transdimensional seismic ambient noise tomography

NASA Astrophysics Data System (ADS)

Zulfakriza, Z.; Saygin, E.; Cummins, P. R.; Widiyantoro, S.; Nugraha, A. D.; Lühr, B.-G.; Bodin, T.

2014-04-01

Delineating the crustal structure of central Java is crucial for understanding its complex tectonic setting. However, seismic imaging of the strong heterogeneity typical of such a tectonically active region can be challenging, particularly in the upper crust where velocity contrasts are strongest and steep body wave ray paths provide poor resolution. To overcome these difficulties, we apply the technique of ambient noise tomography (ANT) to data collected during the Merapi Amphibious Experiment (MERAMEX), which covered central Java with a temporary deployment of over 120 seismometers during 2004 May-October. More than 5000 Rayleigh wave Green's functions were extracted by cross-correlating the noise simultaneously recorded at available station pairs. We applied a fully non-linear 2-D Bayesian probabilistic inversion technique to the retrieved traveltimes. Features in the derived tomographic images correlate well with previous studies, and some shallow structures that were not evident in previous studies are clearly imaged with ANT. The Kendeng Basin and several active volcanoes appear with very low group velocities, and anomalies with relatively high velocities can be interpreted in terms of crustal sutures and/or surface geological features.

Efforts to monitor and characterize the recent increasing seismicity in central Oklahoma

USGS Publications Warehouse

McNamara, Daniel E.; Rubinstein, Justin L.; Myers, Emma; Smoczyk, Gregory M.; Benz, Harley M.; Williams, Robert; Hayes, Gavin; Wilson, David; Herrmann, Robert B.; McMahon, Nicole D; Aster, R.C.; Bergman, E.; Holland, Austin; Earle, Paul

2015-01-01

The sharp increase in seismicity over a broad region of central Oklahoma has raised concerns regarding the source of the activity and its potential hazard to local communities and energy-industry infrastructure. Efforts to monitor and characterize the earthquake sequences in central Oklahoma are reviewed. Since early 2010, numerous organizations have deployed temporary portable seismic stations in central Oklahoma to record the evolving seismicity. A multiple-event relocation method is applied to produce a catalog of central Oklahoma earthquakes from late 2009 into early 2015. Regional moment tensor (RMT) source parameters were determined for the largest and best-recorded earthquakes. Combining RMT results with relocated seismicity enabled determination of the length, depth, and style of faulting occurring on reactivated subsurface fault systems. It was found that the majority of earthquakes occur on near-vertical, optimally oriented (northeast-southwest and northwest-southeast) strike-slip faults in the shallow crystalline basement. In 2014, 17 earthquakes occurred with magnitudes of 4 or larger. It is suggested that these recently reactivated fault systems pose the greatest potential hazard to the region.

Database of multi-parametric geophysical data from the TOMO-DEC experiment on Deception Island, Antarctica

PubMed Central

Ibáñez, Jesús M.; Díaz-Moreno, Alejandro; Prudencio, Janire; Zandomeneghi, Daria; Wilcock, William; Barclay, Andrew; Almendros, Javier; Benítez, Carmen; García-Yeguas, Araceli; Alguacil, Gerardo

2017-01-01

Deception Island volcano (Antarctica) is one of the most closely monitored and studied volcanoes on the region. In January 2005, a multi-parametric international experiment was conducted that encompassed both Deception Island and its surrounding waters. We performed this experiment from aboard the Spanish oceanographic vessel ‘Hespérides’, and from five land-based locations on Deception Island (the Spanish scientific Antarctic base ‘Gabriel de Castilla’ and four temporary camps). This experiment allowed us to record active seismic signals using a large network of seismic stations that were deployed both on land and on the seafloor. In addition, other geophysical data were acquired, including bathymetric high precision multi-beam data, and gravimetric and magnetic profiles. To date, the seismic and bathymetric data have been analysed but the magnetic and gravimetric data have not. We provide P-wave arrival-time picks and seismic tomography results in velocity and attenuation. In this manuscript, we describe the main characteristics of the experiment, the instruments, the data, and the repositories from which data and information can be obtained. PMID:28895947

The P and S wave velocity structure of the mantle beneath eastern Africa and the African superplume anomaly

NASA Astrophysics Data System (ADS)

Mulibo, Gabriel D.; Nyblade, Andrew A.

2013-08-01

P and S relative arrival time residuals from teleseismic earthquakes recorded on over 60 temporary AfricaArray broadband seismic stations deployed in Uganda, Tanzania, and Zambia between 2007 and 2011 have been inverted, together with relative arrival time residuals from earthquakes recorded by previous deployments, for a tomographic image of mantle wave speed variations extending to a depth of 1200 km beneath eastern Africa. The image shows a low-wave speed anomaly (LWA) well developed at shallow depths (100-200 km) beneath the Eastern and Western branches of the Cenozoic East African rift system and northwestern Zambia, and a fast wave speed anomaly at depths ≤ 350 km beneath the central and northern parts of the East African Plateau and the eastern and central parts of Zambia. At depths ≥350 km the LWA is most prominent under the central and southern parts of the East African Plateau and dips to the southwest beneath northern Zambia, extending to a depth of at least 900 km. The amplitude of the LWA is consistent with a ˜150-300 K thermal perturbation, and its depth extent indicates that the African superplume, originally identified as a lower mantle anomaly, is likely a whole mantle structure. A superplume extending from the core-mantle boundary to the surface implies an origin for the Cenozoic extension, volcanism, and plateau uplift in eastern Africa rooted in the dynamics of the lower mantle.

Nanoracks CUBESAT launcher operations

NASA Image and Video Library

2014-08-19

ISS040-E-102490 (19 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer releases a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at left.

Nanoracks CUBESAT launcher

NASA Image and Video Library

2014-08-20

ISS040-E-102420 (20 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer releases a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at left.

Nanoracks CUBESAT launcher

NASA Image and Video Library

2014-08-20

ISS040-E-102425 (20 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer releases a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at left.

The EarthScope USArray Observatories: Status and Results

NASA Astrophysics Data System (ADS)

Woodward, R.; Busby, R.; Alvarez, M.; Schultz, A.; Simpson, D.

2009-05-01

The EarthScope USArray program includes three seismic and two magnetotelluric components. The USArray seismic components consist of the Transportable Array (TA), the Flexible Array (FA), and the Reference Network. The TA component of USArray has now occupied over 700 sites in the western United States, from the Pacific coast through the Rocky Mountains. The three component broadband TA stations are deployed in a grid-like arrangement, with 70 km separation between stations. At any given time there are approximately 400 station sites, occupying a ~2000 km by 800 km "footprint." Each station is operated for two years. The FA component of USArray provides a pool of instruments, ranging from high frequency geophones to three- component broadband sensors, and these instruments are typically deployed for focused geological targets for time periods ranging from days to years. Finally, the Reference Network provides a fixed, permanent reference frame for the TA and FA, with approximately 100 broadband stations deployed across the contiguous US, at roughly 300 km spacing. The magnetotelluric (MT) component of USArray consists of both a fixed reference network as well as a transportable array of instruments that are deployed campaign style, using a 70 km by 70 km grid. The geographical extent of USArray allows unprecedented observation of geophysical targets. Instruments have been deployed across the west and mid-west of the US, with TA stations presently moving into the states spanning a north-south line from North Dakota to Texas. MT observations in Cascadia have been augmented by corresponding observations in Canada. Similarly, as the seismic TA moves east, plans are being developed to collaborate on TA seismic observations on both sides of the US-Canada border in the region of the Great Lakes. We will present the current status of USArray activities and progress to-date, with a special emphasis on standardized data products that are produced from USArray data, including phase picks, wave-field animations, observations of the ambient noise field, and MT transfer functions. We will also provide an overview of USArray deployment plans, to facilitate collaborative experiments and investigations, and discuss opportunities for the seismological education and research communities to participate in and leverage the FA and TA efforts.

Design Development of a Combined Deployment and Pointing System for the International Space Station Neutron Star Interior Composition Explorer Telescope

NASA Technical Reports Server (NTRS)

Budinoff, Jason; Gendreau, Keith; Arzoumanian, Zaven; Baker, Charles; Berning, Robert; Colangelo, Todd; Holzinger, John; Lewis, Jesse; Liu, Alice; Mitchell, Alissa;

Design Development of a Combined Deployment and Pointing System for the International Space Station Neutron Star Interior Composition Explorer Telescope

NASA Technical Reports Server (NTRS)

Budinoff, Jason; Gendreau, Keith; Arzoumanian, Zaven; Baker, Charles; Berning, Robert; Colangelo, TOdd; Holzinger, John; Lewis, Jesse; Liu, Alice; Mitchell, Alissa;

Wind power in Jamaica

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

Chen, A.A.; Daniel, A.R.; Daniel, S.T.

1990-01-01

Parameters to evaluate the potential for using wind energy to generate electricity in Jamaica were obtained. These include the average wind power scaled to a height of 20 m at existing weather stations and temporary anemometer sites, the variation in annual and monthly wind power, and the frequency distribution of wind speed and wind energy available. Four small commercial turbines were assumed to be operating at some of the sites, and the estimated energy captured by them, the time they operated above their cut-in speed and their capacity factors were also determined. Diurnal variations of wind speed and prevailing windmore » directions are discussed and a map showing wind power at various sites was produced. Two stations with long-term averages, Manley and Morant Point, gave results which warranted further investigation. Results from some temporary stations are also encouraging. Mean wind speeds at two other sites in the Caribbean are given for comparison. A method for estimating the power exponent for scaling the wind speed from climatic data is described in Appendix 2.« less

International Space Station (ISS)

NASA Image and Video Library

2007-06-15

Construction resumed on the International Space Station (ISS), as STS-117 astronauts and mission specialists Jim Reilly (on robotic arm), and John “Danny” Olivas joined forces with their colleagues inside the Shuttle and station, and controllers in Houston, to complete the delicate process of folding an older solar array, Port 6 (P6), so that it can be moved from its temporary location to its permanent home during an upcoming Fall scheduled Shuttle mission. The EVA lasted nearly 8 hours.

Selected tether applications in space: An analysis of five selected concepts

NASA Technical Reports Server (NTRS)

1984-01-01

Ground rules and assumptions; operations; orbit considerations/dynamics; tether system design and dynamics; functional requirements; hardware concepts; and safety factors are examined for five scenarios: tethered effected separation of an Earth bound shuttle from the space station; tether effected orbit boost of a spacecraft (AXAF) into its operational orbit from the shuttle; an operational science/technology platform tether deployed from space station; a tether mediated rendezvous involving an OMV tether deployed from space station to rendezvous with an aerobraked OTV returning to geosynchronous orbit from a payload delivery mission; and an electrodynamic tether used in a dual motor/generator mode to serve as the primary energy storage facility for space station.

The Space Shuttle Endeavour's drag chute deploys to slow the orbiter as it rolls out on Runway 22 at Edwards Air Force Base at the conclusion of its 14-day STS-111 mission to the International Space Station

NASA Image and Video Library

2002-06-19

The Space Shuttle Endeavour's drag chute deploys to slow the orbiter as it rolls out on Runway 22 at Edwards Air Force Base at the conclusion of its 14-day STS-111 mission to the International Space Station.

Nanoracks CUBESAT launcher

NASA Image and Video Library

2014-08-20

ISS040-E-102410 (20 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer is about to release a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at left.

The uppermost mantle shear wave velocity structure of eastern Africa from Rayleigh wave tomography: constraints on rift evolution

NASA Astrophysics Data System (ADS)

O'Donnell, J. P.; Adams, A.; Nyblade, A. A.; Mulibo, G. D.; Tugume, F.

2013-08-01

An expanded model of the 3-D shear wave velocity structure of the uppermost mantle beneath eastern Africa has been developed using earthquakes recorded by the AfricaArray East African Seismic Experiment in conjunction with data from permanent stations and previously deployed temporary stations. The combined data set comprises 331 earthquakes recorded on a total of 95 seismic stations spanning Kenya, Uganda, Tanzania, Zambia and Malawi. In this study, data from 149 earthquakes were used to determine fundamental-mode Rayleigh wave phase velocities at periods ranging from 20 to 182 s using the two-plane wave method, and then combined with the similarly processed published measurements and inverted for a 3-D shear wave velocity model of the uppermost mantle. New features in the model include (1) a low-velocity region in western Zambia, (2) a high-velocity region in eastern Zambia, (3) a low-velocity region in eastern Tanzania and (4) low-velocity regions beneath the Lake Malawi rift. When considered in conjunction with mapped seismicity, these results support a secondary western rift branch striking southwestwards from Lake Tanganyika, likely exploiting the relatively weak lithosphere of the southern Kibaran Belt between the Bangweulu Block and the Congo Craton. We estimate a lithospheric thickness of ˜150-200 km for the substantial fast shear wave anomaly imaged in eastern Zambia, which may be a southward subsurface extension of the Bangweulu Block. The low-velocity region in eastern Tanzania suggests that the eastern rift branch trends southeastwards offshore eastern Tanzania coincident with the purported location of the northern margin of the proposed Ruvuma microplate. Pronounced velocity lows along the Lake Malawi rift are found beneath the northern and southern ends of the lake, but not beneath the central portion of the lake.

Managing Risk for Thermal Vacuum Testing of the International Space Station Radiators

NASA Technical Reports Server (NTRS)

Carek, Jerry A.; Beach, Duane E.; Remp, Kerry L.

2000-01-01

The International Space Station (ISS) is designed with large deployable radiator panels that are used to reject waste heat from the habitation modules. Qualification testing of the Heat Rejection System (HRS) radiators was performed using qualification hardware only. As a result of those tests, over 30 design changes were made to the actual flight hardware. Consequently, a system level test of the flight hardware was needed to validate its performance in the final configuration. A full thermal vacuum test was performed on the flight hardware in order to demonstrate its ability to deploy on-orbit. Since there is an increased level of risk associated with testing flight hardware, because of cost and schedule limitations, special risk mitigation procedures were developed and implemented for the test program, This paper introduces the Continuous Risk Management process that was utilized for the ISS HRS test program. Testing was performed in the Space Power Facility at the NASA Glenn Research Center, Plum Brook Station located in Sandusky, Ohio. The radiator system was installed in the 100-foot diameter by 122-foot tall vacuum chamber on a special deployment track. Radiator deployments were performed at several thermal conditions similar to those expected on-orbit using both the primary deployment mechanism and the back-up deployment mechanism. The tests were highly successful and were completed without incident.

Deployment of the P4 Truss SAW during Expedition 13 / STS-115 Joint Operations

NASA Image and Video Library

2006-09-15

S115-E-06184 (14 Sept. 2006) --- Space Shuttle Atlantis astronauts spread a second set of wings for the International Space Station today. The new solar arrays were fully extended at 7:44 a.m. (CDT). The new arrays span a total of 240 feet and have a width of 38 feet. They are attached to the station's newest component, the P3/P4 integrated truss segment. The installation of the P3/P4, which occurred Sept. 12 and the deployment of the arrays set the stage for future expansion of the station.

Deployment of the P4 Truss SAW during Expedition 13 / STS-115 Joint Operations

NASA Image and Video Library

2006-09-15

S115-E-06186 (14 Sept. 2006) --- Space Shuttle Atlantis astronauts spread a second set of wings for the International Space Station today. The new solar arrays were fully extended at 7:44 a.m. (CDT). The new arrays span a total of 240 feet and have a width of 38 feet. They are attached to the station's newest component, the P3/P4 integrated truss segment. The installation of the P3/P4, which occurred Sept. 12 and the deployment of the arrays set the stage for future expansion of the station.

Deployment of the P4 Truss FWD SAW during Expedition 13 and STS-115 EVA Joint Operations

NASA Image and Video Library

2006-09-14

S115-E-05996 (14 Sept. 2006) --- Space Shuttle Atlantis astronauts spread a second set of wings for the International Space Station today. The new solar arrays were fully extended at 7:44 a.m. (CDT). The new arrays span a total of 240 feet and have a width of 38 feet. They are attached to the station's newest component, the P3/P4 integrated truss segment. The installation of the P3/P4, which occurred Tuesday and the deployment of the arrays set the stage for future expansion of the station.

KSC-98pc1659

NASA Image and Video Library

1998-11-06

Workers in the Space Station Processing Facility watch as cables and a crane lift the Passive Common Berthing Mechanism (PCBM) before mating it to the Z1 integrated truss structure, a component of the International Space Station (ISS). The Z1 truss will be used for the temporary installation of the P6 truss segment to the Unity connecting module. The P6 truss segment contains the solar arrays and batteries which will provide early station power. The truss is scheduled to be launched aboard STS-92 in late 1999

KSC-98pc1662

NASA Image and Video Library

1998-11-06

Workers in the Space Station Processing Facility look at the Passive Common Berthing Mechanism (PCBM) that will be attached to the Z1 integrated truss structure, a component of the International Space Station (ISS). The truss will be used for the temporary installation of the P6 truss segment to the Unity connecting module. The P6 truss segment contains the solar arrays and batteries which will provide early station power. The truss is scheduled to be launched aboard STS-92 in late 1999

KSC-98pc1658

NASA Image and Video Library

1998-11-06

Workers in the Space Station Processing Facility look at the Passive Common Berthing Mechanism (PCBM) that will be attached to the Z1 integrated truss structure, a component of the International Space Station (ISS). The Z1 truss will be used for the temporary installation of the P6 truss segment to the Unity connecting module. The P6 truss segment contains the solar arrays and batteries which will provide early station power. The truss is scheduled to be launched aboard STS-92 in late 1999

Performance of 3-Component Nodes in the IRIS Community Wavefield Demonstration Experiment

NASA Astrophysics Data System (ADS)

Sweet, J. R.; Anderson, K. R.; Woodward, R.

2017-12-01

In June 2016, a field crew of 50 students, faculty, industry personnel, and IRIS staff deployed a total of 390 stations as part of a community seismic experiment above an active seismic lineament in north-central Oklahoma. The goals of the experiment were to test new instrumentation and deployment strategies that record the full seismic wavefield, and to advance understanding of earthquake source processes and regional lithospheric structure. The crew deployed 363 3-component, 5Hz Generation 2 Fairfield Z-Land nodes along three seismic lines and in a seven-layer nested gradiometer array. The seismic lines spanned a region 13 km long by 5 km wide. A broadband, 18 station "Golay 3x6" array with an aperture of approximately 5 km was deployed around the gradiometer and seismic lines to collect waveform data from local and regional events. In addition, 9 infrasound stations were deployed in order to capture and identify acoustic events that might be recorded by the seismic array. The variety and geometry of instrumentation deployed was intended to capture the full seismic wavefield generated by the local and regional seismicity beneath the array and the surrounding region. Additional details on the instrumentation and how it was deployed can be found by visiting our website www.iris.edu/wavefields. We present a detailed analysis of noise across the array—including station performance, as well as noise from nearby sources (wind turbines, automobiles, etc.). We report a clear reduction in noise for buried 3-component nodes compared to co-located surface nodes (see Figure). Using the IRIS DMC's ISPAQ client, we present a variety of metrics to evaluate the network's performance. We also present highlights from student projects at the recently-held IRIS advanced data processing short course, which focused on analyzing the wavefield dataset using array processing techniques.

Floating Potential Probe Deployed on the International Space Station

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.

2001-01-01

In the spring and summer of 2000, at the request of the International Space Station (ISS) Program Office, a Plasma Contactor Unit Tiger Team was set up to investigate the threat of the ISS arcing in the event of a plasma contactor outage. Modeling and ground tests done under that effort showed that it is possible for the external structure of the ISS to become electrically charged to as much as -160 V under some conditions. Much of this work was done in anticipation of the deployment of the first large ISS solar array in November 2000. It was recognized that, with this deployment, the power system would be energized to its full voltage and that the predicted charging would pose an immediate threat to crewmembers involved in extravehicular activities (EVA's), as well as long-term damage to the station structure, were the ISS plasma contactors to be turned off or stop functioning. The Floating Potential Probe was conceived, designed, built, and deployed in record time by a crack team of scientists and engineers led by the NASA Glenn Research Center in response to ISS concerns about crew safety.

Arusha Rover Deployable Medical Workstation

NASA Technical Reports Server (NTRS)

Boswell, Tyrone; Hopson, Sonya; Marzette, Russell; Monroe, Gilena; Mustafa, Ruqayyah

2014-01-01

The NSBE Arusha rover concept offers a means of human transport and habitation during long-term exploration missions on the moon. This conceptual rover calls for the availability of medical supplies and equipment for crew members in order to aid in mission success. This paper addresses the need for a dedicated medical work station aboard the Arusha rover. The project team investigated multiple options for implementing a feasible deployable station to address both the medical and workstation layout needs of the rover and crew. Based on layout specifications and medical workstation requirements, the team has proposed a deployable workstation concept that can be accommodated within the volumetric constraints of the Arusha rover spacecraft

SKS splitting results in central Italy and Dinaric region inside the AlpArray-CASE project

NASA Astrophysics Data System (ADS)

Salimbeni, S.; Prevolnik, S.; Pondrelli, S.; Molinari, I.; Stipcevic, J.; Kissling, E.; Šipka, V.; Herak, M.

2017-12-01

In the framework of the AlpArray project (AlpArray Seismic Network, 2015), the complementary "Central Adriatic Seismic Experiment" (CASE; AlpArray Seismic Network, 2016) was established as collaboration between ETH Zürich, University of Zagreb, INGV and Republic Hydrometeorological Service of Republic of Srpska. The CASE project consists of 9 temporary stations, installed in October 2016, located in Bosnia and Herzegovina, Croatia and Italy. Temporary broadband seismic stations, with the permanent stations present in the region shared by the Croatian Seismological Service and INGV, make an almost continuous transect cutting the Central-Southern Appenines, the central Adriatic region, central External Dinarides and finishing at the eastern margin of the Internal Dinarides. The presence of the the Apenninic and Dinarides slabs, verging in opposite directions and plunging along the opposite sides of the Adriatic plate, make this area a peculiar spot to understand the complex dynamic of the region. Various tomographic images (e.g. Bijwaard and Spakman, 2000; Piromallo and Morelli, 2003) shows not continuous slabs under the Appenines and the Dinarides, suggesting the presence of slab-gaps right beneath the region covered by the CASE experiment. Here we present the preliminary results of the SKS splitting analysis performed on the data recorded by the temporary and permanent seismic stations included in the CASE project. The new results, in combination with previous interpretation, will provide clues about how Northern and Southern Apennines are connected at depth, how the slab rollback of the Apennines thrust belt acted and if and how the Apennines are in relation with the Dinaric region. Together with the measurements from previous studies and from the AlpArray project, our new data will support the mapping of the seismic anisotropy deformation pattern from Western Alps to Pannonian region.

Lithospheric Layering beneath the Contiguous United States Constrained by S-to-P Receiver Functions

NASA Astrophysics Data System (ADS)

Liu, L.; Liu, K. H.; Kong, F.; Gao, S. S.

2017-12-01

The greatly-improved spatial coverage of broadband seismic stations as a result of the deployment of the EarthScope Transportable Array (TA) stations and the diversity of tectonic environments in the contiguous United States provide a unique opportunity to investigate the depth variation and nature of intra-lithospheric interfaces in different tectonic regimes. A total of 284,121 high-quality S-to-P receiver functions (SRFs) are obtained from 3,809 broadband seismic stations in the TA and other permanent and temporary deployments in the contiguous United States. The SRFs are computed using frequency domain deconvolution, and are stacked in consecutive circles with a radius of 2°. They are converted to depth series after move-out corrections using the IASP91 Earth model. Similar to previous SRF studies, a robust negative arrival, representing a sharp discontinuity of velocity reduction with depth, is visible in virtually all the stacked traces in the depth range of 30-110 km. Beneath the western US, the depth of this discontinuity is 69±17 km, and beneath the eastern US, it ranges from 75 to 90 km, both of which are comparable to the depth of the tomographically-determined lithosphere-asthenosphere boundary (LAB). In contrast, the depth of the discontinuity beneath the central US is 83±10 km which is significantly smaller than the 250 km LAB depth determined by seismic surface wave tomography. Based on previous seismic tomography, shear-wave splitting and mantle xenolith studies, we interpret this discontinuity as the top of a frozen-in layer of volatile-rich melt beneath the central US. The observations and the discrepancy between the SRF and seismic tomography results for the central US as well as the amplitude of the corresponding arrival on the SRFs may be explained by spatial variations of the thickness of the transitional layer between the "pure" lithosphere and the "pure" asthenosphere. Under this hypothesis, the consistency between the results from the SRFs and seismic tomography for the western and eastern US suggests a thin transitional layer. On the contrary, a thick transitional layer is inferred for the central US. For this area, while the long-period surface waves can detect the transitional layer, the gradual natural of its lower boundary makes it hard for the short wavelength SRFs to detect.

New Insights on Seismicity and the Velocity Structure beneath the Western Segment of the North Anatolian Fault Zone

NASA Astrophysics Data System (ADS)

Teoman, U.; Altuncu Poyraz, S.; Kahraman, M.; Mutlu, A. K.; Cambaz, D.; Turkelli, N.; Thompson, D. A.; Rost, S.; Houseman, G. A.; Utkucu, M.

2014-12-01

To extensively investigate the upper crustal structure beneath the western segment of the North Anatolian Fault Zone (NAFZ) in Sakarya and the surroundings, a temporary seismic network consisting of 70 stations (with nearly 7km station spacing) was deployed in early May 2012 and operated for 18 months during the Faultlab experiment encompassing both the northern and southern strands of the fault in between the area of 1999 İzmit and Düzce mainshock ruptures. With the help of this new and extensive data set, our main objective is to provide new insights on the most recent micro-seismic activity and the velocity structure beneath the region. Out of 2437 events contaminated by the explosions, we extracted 1344 well located earthquakes with a total of 31595 P and 18512 S phase readings which lead to an avarage Vp/Vs ratio of ~1.82 extracted from the wadati diagram. The enhanced station coverage decreased the magnitude threshold to 0.1 where the horizontal and vertical location errors did not exceed 0.5 km and 2.0 km, respectively. Average RMS values were calculated within the range of 0.05-0.4 seconds. We observed significant seismic activity along both branches of the fault where the depth of the seismogenic zone was confined to 15 km. Focal parameters of 41 earthquakes with magnitudes greater than 1.8 were also determined using both Regional Moment Tensor Inversion and P first arrival time methods. Focal mechanism solutions confirm that Sakarya and its vicinity could be defined by a compressional regime showing a primarily oblique-slip motion character. Furthermore, we selected the earthquakes recorded by at least 8 stations with azimuthal gaps less than 200° for the ongoing tomographic inversion that would enable us to accurately map the complex upper crustal velocity structure with high resolution beneath this segment of the NAFZ.

Around Marshall

NASA Image and Video Library

1979-08-13

Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. And construction methods had to be efficient due to limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. Included in the plans for the space station was a space telescope. This telescope would be attached to the space station and directed towards outerspace. Astronomers hoped that the space telescope would provide a look at space that is impossible to see from Earth because of Earth's atmosphere and other man made influences. In an effort to make replacement and repairs easier on astronauts the space telescope was designed to be modular. Practice makes perfect as demonstrated in this photo: an astronaut practices moving modular pieces of the space telescope in the Neutral Buoyancy Simulator (NBS) at MSFC. The space telescope was later deployed in April 1990 as the Hubble Space Telescope.

M-Split: A Graphical User Interface to Analyze Multilayered Anisotropy from Shear Wave Splitting

NASA Astrophysics Data System (ADS)

Abgarmi, Bizhan; Ozacar, A. Arda

2017-04-01

Shear wave splitting analysis are commonly used to infer deep anisotropic structure. For simple cases, obtained delay times and fast-axis orientations are averaged from reliable results to define anisotropy beneath recording seismic stations. However, splitting parameters show systematic variations with back azimuth in the presence of complex anisotropy and cannot be represented by average time delay and fast axis orientation. Previous researchers had identified anisotropic complexities at different tectonic settings and applied various approaches to model them. Most commonly, such complexities are modeled by using multiple anisotropic layers with priori constraints from geologic data. In this study, a graphical user interface called M-Split is developed to easily process and model multilayered anisotropy with capabilities to properly address the inherited non-uniqueness. M-Split program runs user defined grid searches through the model parameter space for two-layer anisotropy using formulation of Silver and Savage (1994) and creates sensitivity contour plots to locate local maximas and analyze all possible models with parameter tradeoffs. In order to minimize model ambiguity and identify the robust model parameters, various misfit calculation procedures are also developed and embedded to M-Split which can be used depending on the quality of the observations and their back-azimuthal coverage. Case studies carried out to evaluate the reliability of the program using real noisy data and for this purpose stations from two different networks are utilized. First seismic network is the Kandilli Observatory and Earthquake research institute (KOERI) which includes long term running permanent stations and second network comprises seismic stations deployed temporary as part of the "Continental Dynamics-Central Anatolian Tectonics (CD-CAT)" project funded by NSF. It is also worth to note that M-Split is designed as open source program which can be modified by users for additional capabilities or for other applications.

Ambient Noise Tomography of the East African Rift System in Mozambique

NASA Astrophysics Data System (ADS)

Domingues, Ana; Custódio, Susana; Chamussa, José; Silveira, Graça; Chang, Sung-Joon; Lebedev, Sergei; Ferreira, Ana; Fonseca, João

2014-05-01

Project MOZART - MOZAmbique Rift Tomography (funded by FCT, Lisbon) deployed a total of 30 temporary broadband seismic stations from the SEIS-UK Pool in central and south Mozambique and in NE South Africa. The purpose of this project is the study of the East African Rift System (EARS) in Mozambique. We estimated preliminary locations with the data recorded from April 2011 to July 2012. A total of 307 earthquakes were located, with ML magnitudes ranging from 0.9 to 3.9. We observe a linear northeast-southwest distribution of the seismicity that seems associated to the Inhaminga fault. The seismicity in the northeast sector correlates well with the topography, tracing the Urema rift valley. The seismicity extends to ~300km, reaching the M7 2006 Machaze earthquake area. In order to obtain an initial velocity model of the region, we applied the ambient noise method to the MOZART data and two additional stations from AfricaARRAY. Cross-correlations were computed between all pairs of stations, and we obtained Rayleigh wave group velocity dispersion curves for all interstation paths, in the period range from 3 to 50 seconds. The geographical distribution of the group velocity anomalies is in good agreement with the geology map of Mozambique, having lower group velocities in sedimentary basins areas and higher velocities in cratonic regions. We also observe two main regions with different velocities that may indicate a structure not proposed in previous studies. We perform a three-dimensional inversion to obtain the S-wave velocity of the crust and upper mantle, and in order to extend the investigation to longer periods we apply a recent implementation of the surface-wave two-station method (teleseismic interferometry), while augmenting our dataset with Rayleigh wave phase velocities curves in broad period ranges. In this way we expect to be able to look into the lithosphere-asthenosphere depth range.

The crustal structure along the 1999 Izmit/Düzce rupture of the North-Anatolian Fault

NASA Astrophysics Data System (ADS)

Sebastian, Rost; David, Cornwell; David, Thompson; Greg, Houseman; Metin, Kahraman; Ugur, Teoman; Selda, Altuncu-Poyraz; Niyazi, Turkelli; Andrew, Frederiksen; Stephane, Rondenay; Tim, Wright

2015-04-01

Deformation along continental strike-slip faults is localized onto narrow fault zones at the surface, which may slip suddenly and catastrophically in earthquakes. On the other hand, strain in the upper mantle is more broadly distributed and is thought to occur by continuous ductile creep. The transition between these two states is poorly understood although it controls the behaviour of the fault zone during the earthquake loading cycle. To understand the structure of and strain distribution across the North-Anatolian Fault Zone (NAFZ) we deployed temporary seismic stations in the region of the 1999 Izmit (M7.5) and Düzce (M7.2) earthquakes. The rectangular array consisted of 66 seismic stations with a nominal station spacing of 7 km and seven additional stations forming a semi-circular ring towards the east (Dense Array for Northern Anatolia - DANA). Using this very dense seismic dataset and a combination of established (e.g. H-k stacking and common conversion point migration) and novel (scattering migration and scattering inversion) seismic processing techniques allows unprecedented resolution of the crustal structure in this region. This study resolves sharp changes in crustal structure across and along the surface expression of the two branches of the NAFZ at scale lengths less than 10 km at mid to lower-crustal depths. The results indicate that the northern NAFZ branch depth extent varies from the mid-crust to the upper mantle and it is likely to be less than 5 km wide throughout the crust. We furthermore resolve a high velocity lower crust and a region of crustal underthrusting that might add strength to a heterogeneous crust and may play a role in dictating the variation in faulting style and postseismic deformation in this region of the NAFZ. The results are consistent with a narrow fault zone accommodating postseismic deformation in the lower crust, as opposed to a broad ductile region below the seismogenic region of the fault.

Concept for a lunar array for very low frequency radio astronomy

NASA Technical Reports Server (NTRS)

Marsh, Kenneth A.; Mahoney, Michael J.; Kuiper, Thomas B. H.; Jones, Dayton L.

1992-01-01

We discuss the design considerations relevant to a very low frequency array, to be deployed on the lunar near side during an early expedition. Such an array would operate in the frequency range 1-10 MHz, and would consist nominally of 20 antennas distributed over a region approximately 40 km in extent. Each antenna station would consist of a crossed-dipole antenna, together with a receiver, digitizer, solar cells, and batteries. In addition, the station will contain a UHF transmitter for relaying the digitized signal to a central station where it will be transmitted to Earth for subsequent processing, including cross-correlation with signals from other antennas. Each antenna station (including the central station) would be deployed as a self-contained unit, mounted on a miniature robotic vehicle. No fixed structures are required for the array.

Large Deployable Reflector (LDR) Requirements for Space Station Accommodations

NASA Technical Reports Server (NTRS)

Crowe, D. A.; Clayton, M. J.; Runge, F. C.

1985-01-01

Top level requirements for assembly and integration of the Large Deployable Reflector (LDR) Observatory at the Space Station are examined. Concepts are currently under study for LDR which will provide a sequel to the Infrared Astronomy Satellite and the Space Infrared Telescope Facility. LDR will provide a spectacular capability over a very broad spectral range. The Space Station will provide an essential facility for the initial assembly and check out of LDR, as well as a necessary base for refurbishment, repair and modification. By providing a manned platform, the Space Station will remove the time constraint on assembly associated with use of the Shuttle alone. Personnel safety during necessary EVA is enhanced by the presence of the manned facility.

Large Deployable Reflector (LDR) requirements for space station accommodations

NASA Astrophysics Data System (ADS)

Crowe, D. A.; Clayton, M. J.; Runge, F. C.

1985-04-01

Top level requirements for assembly and integration of the Large Deployable Reflector (LDR) Observatory at the Space Station are examined. Concepts are currently under study for LDR which will provide a sequel to the Infrared Astronomy Satellite and the Space Infrared Telescope Facility. LDR will provide a spectacular capability over a very broad spectral range. The Space Station will provide an essential facility for the initial assembly and check out of LDR, as well as a necessary base for refurbishment, repair and modification. By providing a manned platform, the Space Station will remove the time constraint on assembly associated with use of the Shuttle alone. Personnel safety during necessary EVA is enhanced by the presence of the manned facility.

Optimal Base Station Density of Dense Network: From the Viewpoint of Interference and Load.

PubMed

Feng, Jianyuan; Feng, Zhiyong

2017-09-11

Network densification is attracting increasing attention recently due to its ability to improve network capacity by spatial reuse and relieve congestion by offloading. However, excessive densification and aggressive offloading can also cause the degradation of network performance due to problems of interference and load. In this paper, with consideration of load issues, we study the optimal base station density that maximizes the throughput of the network. The expected link rate and the utilization ratio of the contention-based channel are derived as the functions of base station density using the Poisson Point Process (PPP) and Markov Chain. They reveal the rules of deployment. Based on these results, we obtain the throughput of the network and indicate the optimal deployment density under different network conditions. Extensive simulations are conducted to validate our analysis and show the substantial performance gain obtained by the proposed deployment scheme. These results can provide guidance for the network densification.

System definition study of deployable, non-metallic space structures

NASA Technical Reports Server (NTRS)

Stimler, F. J.

1984-01-01

The state of the art for nonmetallic materials and fabrication techniques suitable for future space structures are summarized. Typical subsystems and systems of interest to the space community that are reviewed include: (1) inflatable/rigidized space hangar; (2) flexible/storable acoustic barrier; (3) deployable fabric bulkhead in a space habitat; (4) extendible tunnel for soft docking; (5) deployable space recovery/re-entry systems for personnel or materials; (6) a manned habitat for a space station; (7) storage enclosures external to the space station habitat; (8) attachable work stations; and (9) safe haven structures. Performance parameters examined include micrometeoroid protection; leakage rate prediction and control; rigidization of flexible structures in the space environment; flammability and offgassing; lifetime for nonmetallic materials; crack propagation prevention; and the effects of atomic oxygen and space debris. An expandable airlock for shuttle flight experiments and potential tethered experiments from shuttle are discussed.

Moho geometry along a north-south passive seismic transect through Central Australia

NASA Astrophysics Data System (ADS)

Sippl, Christian

2016-04-01

Receiver functions from a temporary deployment of 25 broadband stations along a north-south transect through Central Australia are used to retrieve crustal and uppermost mantle structural constraints from a combination of different methods. Using H-K stacking as well as receiver function inversion, overall thick crust with significant thickness variation along the profile (40 to ≥ 55 km) is found. Bulk crustal vp/vs values are largely in the felsic to intermediate range, with the southernmost stations on the Gawler Craton exhibiting higher values in excess of 1.8. A common conversion point (CCP) stacking profile shows three major discontinuities of the crust-mantle boundary: (1) a two-sided Moho downwarp beneath the Musgrave Province, which has previously been associated with the Neoproterozoic to early Cambrian Petermann Orogeny, (2) a Moho offset along the Redbank Shear Zone further north attributed to the Middle to Late Paleozoic Alice Springs Orogeny, and (3) another Moho offset further north, located at the boundary between the Davenport and Warramunga Provinces, which has not been imaged before. In all cases, the difference in crustal thickness between the two sides of the offset is > 8-10 km. Unlike the two southern Moho offsets, the northernmost one does not coincide with a prominent gravity anomaly. Its location and the absence of known reactivation events in the region make it likely that it belongs to a Proterozoic suture zone that marks a previously unknown block boundary within the North Australian Craton.

TEDESE project: preliminary results

NASA Astrophysics Data System (ADS)

Buforn, E.; Martín Dávila, J.; Bock, G.; Pazos, A.; Udías, A.; Hanka, H.; Gárate, J.; Perez Peña, A.

2003-04-01

The TEDESE (Terremotos y Deformación Cortical en el Sur de España) project is a joint project of the Universidad Complutense de Madrid (UCM) and Real Instituto y Observatorio de la Armada de San Fernando, Cádiz (ROA) supported by the Spanish Ministerio de Ciencia y Tecnología with the participation of the GeoforschungZentrum, Potsdam (GFZ). The project started on January 2001 and it will extend till December 2003. As part of this project a temporal network of 10 broad-band seismological stations, which will complete those already existing in the zone, have been installed for a period of 20 months (October 01-June 03) in southern Spain and northern Africa. This temporary net has recorded, till November 2002, more than 760 regional earthquakes, with magnitudes between 1.7 and 5.1. We have studied in detail two shallow events occurred in Gergal (Almería, SE Spain, 04-02- 02, M=5.0) and Bullas (Murcia, SE Span, 06-08-02, M=4.8), its aftershocks series and two intermediate depth (h=90km) earthquakes located in Málaga (Spain, M=4.5). GPS time series, from permanent GPS stations deployed at the region by ROA and other institutions, have been produced and velocity vectors have been derived. GPS data coming from previous periodic field campaigns carried out in the region by ROA since 1996 are being reprocessed, and a new GPS campaing is planned for June 2003.

Definition of satellite servicing technology development missions for early space stations. Volume 2: Technical

NASA Technical Reports Server (NTRS)

1983-01-01

Early space station accommodation, build-up of space station manipulator capability, on-orbit spacecraft assembly test and launch, large antenna structure deployment, service/refurbish satellite, and servicing of free-flying materials processing platform are discussed.

Improving Station Performance by Building Isolation Walls in the Tunnel

NASA Astrophysics Data System (ADS)

Jia, Yan; Horn, Nikolaus; Leohardt, Roman

2014-05-01

Conrad Observatory is situated far away from roads and industrial areas on the Trafelberg in Lower Austria. At the end of the seismic tunnel, the main seismic instrument of the Observatory with a station code CONA is located. This station is one of the most important seismic stations in the Austrian Seismic Network (network code OE). The seismic observatory consists of a 145m long gallery and an underground laboratory building with several working areas. About 25 meters away from the station CONA, six temporary seismic stations were implemented for research purposes. Two of them were installed with the same equipment as CONA, while the remaining four stations were set up with digitizers having lower noise and higher resolution (Q330HR) and sensors with the same type (STS-2). In order to prevent possible disturbances by air pressure and temperature fluctuation, three walls were built inside of the tunnel. The first wall is located ca 63 meters from the tunnel entrance, while a set of double walls with a distance of 1.5 meters is placed about 53 meters from the first isolation wall but between the station CONA and the six temporary stations. To assess impact of the isolation walls on noise reduction and detection performance, investigations are conducted in two steps. The first study is carried out by comparing the noise level and detection performance between the station CONA behind the double walls and the stations in front of the double walls for verifying the noise isolation by the double walls. To evaluate the effect of the single wall, station noise level and detection performance were studied by comparing the results before and after the installation of the wall. Results and discussions will be presented. Additional experiment is conducted by filling insulation material inside of the aluminium boxes of the sensors (above and around the sensors). This should help us to determine an optimal insulation of the sensors with respect to pressure and temperature fluctuations.

Space Acceleration Measurement System-II: Microgravity Instrumentation for the International Space Station Research Community

NASA Technical Reports Server (NTRS)

Sutliff, Thomas J.

1999-01-01

The International Space Station opens for business in the year 2000, and with the opening, science investigations will take advantage of the unique conditions it provides as an on-orbit laboratory for research. With initiation of scientific studies comes a need to understand the environment present during research. The Space Acceleration Measurement System-II provides researchers a consistent means to understand the vibratory conditions present during experimentation on the International Space Station. The Space Acceleration Measurement System-II, or SAMS-II, detects vibrations present while the space station is operating. SAMS-II on-orbit hardware is comprised of two basic building block elements: a centralized control unit and multiple Remote Triaxial Sensors deployed to measure the acceleration environment at the point of scientific research, generally within a research rack. Ground Operations Equipment is deployed to complete the command, control and data telemetry elements of the SAMS-II implementation. Initially, operations consist of user requirements development, measurement sensor deployment and use, and data recovery on the ground. Future system enhancements will provide additional user functionality and support more simultaneous users.

Broadband seismic noise attenuation versus depth at the Albuquerque Seismological Laboratory

USGS Publications Warehouse

Hutt, Charles R.; Ringler, Adam; Gee, Lind

2017-01-01

Seismic noise induced by atmospheric processes such as wind and pressure changes can be a major contributor to the background noise observed in many seismograph stations, especially those installed at or near the surface. Cultural noise such as vehicle traffic or nearby buildings with air handling equipment also contributes to seismic background noise. Such noise sources fundamentally limit our ability to resolve earthquake‐generated signals. Many previous seismic noise versus depth studies focused separately on either high‐frequency (>1  Hz">>1  Hz) or low‐frequency (<0.05  Hz"><0.05  Hz) bands. In this study, we use modern high‐quality broadband (BB) and very broadband (VBB) seismometers installed at depths ranging from 1.5 to 188 m at the Albuquerque Seismological Laboratory to evaluate noise attenuation as a function of depth over a broad range of frequencies (0.002–50 Hz). Many modern seismometer deployments use BB or VBB seismometers installed at various depths, depending on the application. These depths range from one‐half meter or less in aftershock study deployments, to one or two meters in the Incorporated Research Institutions for Seismology Transportable Array (TA), to a few meters (shallow surface vaults) up to 100 m or more (boreholes) in the permanent observatories of the Global Seismographic Network (GSN). It is important for managers and planners of these and similar arrays and networks of seismograph stations to understand the attenuation of surface‐generated noise versus depth so that they can achieve desired performance goals within their budgets as well as their frequency band of focus. The results of this study will assist in decisions regarding BB and VBB seismometer installation depths. In general, we find that greater installation depths are better and seismometer emplacement in hard rock is better than in soil. Attenuation for any given depth varies with frequency. More specifically, we find that the dependence of depth will be application dependent based on the frequency band and sensitive axes of interest. For quick deployments (like aftershock studies), 1 m may be deep enough to produce good data, especially when the focus is on vertical data where temperature stability fundamentally limits the low‐frequency noise levels and little low‐frequency data will be used. For temporary (medium‐term) deployments (e.g., TA) where low cost can be very important, 2–3 m should be sufficient, but such shallow installations will limit the ability to resolve low‐frequency signals, especially on horizontal components. Of course, one should try for maximum burial depth within the budget when there is interest in using the data for low‐frequency applications. For long‐term deployments like the permanent observatories of the GSN and similar networks, 100–200 m depth in hard rock is desirable to achieve lowest noise, although 30–60 m may be acceptable.

Imaging the lithosphere-asthenosphere boundary across the transition from Phanerozoic Europe to the East-European Craton with S-receiver functions

NASA Astrophysics Data System (ADS)

Knapmeyer-Endrun, Brigitte; Krüger, Frank

2013-04-01

Cratons are characterized by their thick lithospheric roots. In the case of the Eastern European Craton, high seismic velocities have been imaged tomographically to more than 200 km depth. However, the exact depth extent of the cratonic lithosphere and especially the properties of the transition to a much thinner lithosphere beneath Phanerozoic central Europe still remain under discussion. Whereas a number of recent seismic campaigns has significantly increased the knowledge about crustal structure and Moho topography in central Europe, comparably detailed, 3-D information on upper mantle structure, e.g. the lithosphere-asthenosphere boundary (LAB), is yet missing. The international PASSEQ experiment, which was conducted from 2006 to 2008, strived to fill this gap with the deployment of 196 seismological stations, roughly a quarter of which were equipped with broad-band sensors, between eastern Germany and Lithuania. With a mean inter-station distance of 60 km, reduced to about 20 km along the central profile, PASSEQ offers the densest coverage for a passive experiment in this region yet. Here, we present first S-receiver function results for this data set, complemented by additional data from national and regional networks and other temporary deployments. This increases the number of available broad-band stations to almost 300, though mostly located to the west of the Trans-European Suture Zone (TESZ). Besides, we also process data from short-period (1 s and 5 s) sensors. The visibility of mantle-transition zone phases, even in single-station data, provides confidence in the quality of the obtained S-receiver functions. Moho conversions can be confidently identified for all stations. In case of a low-velocity sedimentary cover, as found for example in the Polish Basin, the S-receiver functions even provide clearer information on Moho depth than the P-receiver functions, which are heavily disturbed by shallow reverberations. For stations west of the TESZ, a clear negative conversion, indicative of a velocity decrease with depth and identified as the LAB, is detected from an average depth of 90 km. This is in good agreement with estimates of the lithospheric thickness beneath Phanerozoic Europe from surface waves. Highest amplitudes of this conversion are obtained when the data are low-passed around 3 s. This indicates that the corresponding interface is less sharp than the Moho, which shows highest amplitudes for a 1 s-lowpass, but still limited in width to about 15 km. For stations located on the East European Craton, we likewise observe a negative conversion caused by a velocity reduction at about 100 km depth. However, in this case, the cause cannot be the tomographically imaged LAB. We rather explain the observation as mid-lithospheric discontinuity, which has also been found in S-receiver functions from other cratonic areas worldwide. At some of the cratonic stations, we observe a negative conversion of similar size that could be related to a velocity decrease at 190 km to 230 km depth, in agreement with depth estimates for the cratonic LAB. The lack of this observation for the other cratonic stations might imply spatial variations in the sharpness of the corresponding velocity change.

Sensor Emplacement Techniques and Seismic Noise Analysis for USArray Transportable Array Seismic Stations

NASA Astrophysics Data System (ADS)

Busby, Robert; Frassetto, Andy; Hafner, Katrin; Woodward, Robert; Sauter, Allan

2013-04-01

In preparation for deployment of EarthScope's USArray Transportable Array (TA) in Alaska beginning in 2014, the National Science Foundation (NSF) is supporting exploratory work on seismic station design, sensor emplacement and communication concepts appropriate for the challenging high-latitude environment that is proposed for deployment. IRIS has installed several experimental stations to evaluate different sensor emplacement schemes both in Alaska and the lower-48 U.S. The goal of these tests is to maintain or enhance a station's noise performance while minimizing its footprint and the equipment, materials, and overall expense required for its construction. Motivating this approach are recent developments in posthole broadband seismometer design and the unique conditions for operating in Alaska, where there are few roads, cellular communications are scarce, most areas are only accessible by small plane or helicopter, and permafrost underlies much of the northern tundra. In this study we review our methods used for directly emplacing of broadband seismometers in comparison to the current methods used to deploy TA stations. These primarily focus on using an auger to drill three to five meters, beneath the active layer of the permafrost, or coring directly into surface bedrock to one meter depth using a portable drill. Both methods have proven logistically effective in trials. Subsequent station performance can be quantitatively assessed using probability density functions summed from power spectral density estimates. These are calculated for the continuous time series of seismic data recorded for each channel of the seismometer. There are five test stations currently operating in Alaska. One was deployed in August 2011 and the remaining four in October 2012. Our results show that the performance of seismometers in Alaska with auger-hole or core-hole installations equals or exceeds that of the quietest TA stations in the lower-48, particularly at long periods, and in exceptional cases approaches the performance of the GSN low noise model. The station at Poker Flat Research Range, Alaska co-locates a sensor in a 5 meter deep auger hole with a 2 meter deep TA tank installation typical of the lower-48. The augered seismometer is currently over 20 dB quieter at periods over 40 seconds than the TA tank installation. Similar performance has been observed at other TA stations, which also compare favorably to co-located permanent stations.

New seismic instrumentation packaged for all terrestrial environments (including the quietest observatories!).

NASA Astrophysics Data System (ADS)

Parker, Tim; Devanney, Peter; Bainbridge, Geoff; Townsend, Bruce

2017-04-01

The march to make every type of seismometer, weak to strong motion, reliable and economically deployable in any terrestrial environment continues with the availability of three new sensors and seismic systems including ones with over 200dB of dynamic range. Until recently there were probably 100 pier type broadband sensors for every observatory type pier, not the types of deployments geoscientists are needing to advance science and monitoring capability. Deeper boreholes are now the recognized quieter environments for best observatory class instruments and these same instruments can now be deployed in direct burial environments which is unprecedented. The experiences of facilities in large deployments of broadband seismometers in continental scale rolling arrays proves the utility of packaging new sensors in corrosion resistant casings and designing in the robustness needed to work reliably in temporary deployments. Integrating digitizers and other sensors decreases deployment complexity, decreases acquisition and deployment costs, increases reliability and utility. We'll discuss the informed evolution of broadband pier instruments into the modern integrated field tools that enable economic densification of monitoring arrays along with supporting new ways to approach geoscience research in a field environment.

Seismic monitoring of the bedload transport in La Réunion Island rivers during tropical cyclones

NASA Astrophysics Data System (ADS)

Gonzalez, Alicia; Fontaine, Fabrice. R.; Burtin, Arnaud; Barruol, Guilhem; Recking, Alain; Join, Jean-Lambert; Delcher, Eric

2017-04-01

La Réunion Island, located in the western Indian Ocean, undergoes heavy annual precipitations during the rainy season (Dec to Apr) and particularly during tropical depressions and cyclones. Large rainfalls that affect this volcanic island modify the stream dynamic and control the sediment transport and the very active erosion. However, in situ characterization of sediment transport is difficult during high water stage, requiring indirect observation such as seismic noise. In order to monitor spatial and temporal variations of the river's bed-load during tropical cyclones from the high-frequency seismic noise in La Réunion, we deployed a temporary seismic network of 9 three-component broadband seismometers along two rivers: Rivière des Pluies and Rivière du Mât, both located on the northern side of the island. Seismic data are supplemented by meteorological and hydrological stations installed in these experimental watersheds. They provide valuable data such as precipitations, water discharge and water level. We also characterized the stream morphology and the bed surface grain size distribution to set the current characteristics and we aim to repeat this analyze after each flood event in order to quantify the effect of the flood episode on the sediment transport. We present the results of the signature of the cyclone Bejisa which passed close to the island in January 2014 recorded at three broadband seismic stations, among which two are located near instrumented streams: station SALA installed close to the Rivière du Mât and the permanent GEOSCOPE seismic station RER installed in a 4.7 km long tunnel close to the Rivière de l'Est. The third station MAID is used as a reference station since it is located on a summit (2.190 km altitude) and far from any active river. We observe a significant increase of the precipitation as the cyclone eye was at 300 km to the island and the associated increase of the water discharge clearly generates a sudden increase of the seismic signal power spectral density above 1 Hz. Comparison between the high-frequency seismic signals measured at the three stations and the hydrological and meteorological data allow us identifying the characteristics of the river bedload.

Aftershocks of the India Republic Day Earthquake: the MAEC/ISTAR Temporary Seismograph Network

NASA Astrophysics Data System (ADS)

Bodin, P.; Horton, S.; Johnston, A.; Patterson, G.; Bollwerk, J.; Rydelek, P.; Steiner, G.; McGoldrick, C.; Budhbhatti, K. P.; Shah, R.; Macwan, N.

2001-05-01

The MW=7.7 Republic Day (26 January, 2001) earthquake on the Kachchh in western India initiated a strong sequence of small aftershocks. Seventeen days following the mainshock, we deployed a network of portable digital event recorders as a cooperative project of the Mid America Earthquake Center in the US and the Institute for Scientific and Technological Advanced Research. Our network consisted of 8 event-triggered Kinemetrics K2 seismographs with 6 data channels (3 accelerometer, 3 Mark L-28/3d seismometer) sampled at 200 Hz, and one continuously-recording Guralp CMG40TD broad-band seismometer sampled at 220 Hz. This network was in place for 18 days. Underlying our network deployment was the notion that because of its tectonic and geologic setting the Republic Day earthquake and its aftershocks might have source and/or propagation characteristics common to earthquakes in stable continental plate-interiors rather than those on plate boundaries or within continental mobile belts. Thus, our goals were to provide data that could be used to compare the Republic Day earthquake with other earthquakes. In particular, the objectives of our network deployment were: (1) to characterize the spatial distribution and occurrence rates of aftershocks, (2) to examine source characteristics of the aftershocks (stress-drops, focal mechanisms), (3) to study the effect of deep unconsolidated sediment on wave propagation, and (4) to determine if other faults (notably the Allah Bundh) were simultaneously active. Most of our sites were on Jurassic bedrock, and all were either free-field, or on the floor of light structures built on rock or with a thin soil cover. However, one of our stations was on a section of unconsolidated sediments hundreds of meters thick adjacent to a site that was subjected to shaking-induced sediment liquefaction during the mainshock. The largest aftershock reported by global networks was an MW=5.9 event on January 28, prior to our deployment. The largest aftershock we recorded was MW=5.3. Our network recorded signals from nearly 2000 earthquakes, all on-scale.

Air-dropped sensor network for real-time high-fidelity volcano monitoring

USGS Publications Warehouse

Song, W.-Z.; Huang, R.; Xu, M.; Ma, A.; Shirazi, B.; LaHusen, R.

2009-01-01

This paper presents the design and deployment experience of an air-dropped wireless sensor network for volcano hazard monitoring. The deployment of five stations into the rugged crater of Mount St. Helens only took one hour with a helicopter. The stations communicate with each other through an amplified 802.15.4 radio and establish a self-forming and self-healing multi-hop wireless network. The distance between stations is up to 2 km. Each sensor station collects and delivers real-time continuous seismic, infrasonic, lightning, GPS raw data to a gateway. The main contribution of this paper is the design and evaluation of a robust sensor network to replace data loggers and provide real-time long-term volcano monitoring. The system supports UTC-time synchronized data acquisition with 1ms accuracy, and is online configurable. It has been tested in the lab environment, the outdoor campus and the volcano crater. Despite the heavy rain, snow, and ice as well as gusts exceeding 120 miles per hour, the sensor network has achieved a remarkable packet delivery ratio above 99% with an overall system uptime of about 93.8% over the 1.5 months evaluation period after deployment. Our initial deployment experiences with the system have alleviated the doubts of domain scientists and prove to them that a low-cost sensor network system can support real-time monitoring in extremely harsh environments. Copyright 2009 ACM.

Ground Node

DTIC Science & Technology

2009-09-30

Node deployment. Original plans were to deploy directly to Fort Jefferson on Dry Tortugas (near Key West, FL). Current plans are to initially deploy...to the USCG Station on Ismoralda Key for training operations; then deploy at a to-be- determined date to Fort Jefferson on Dry Tortugas . During FY09...Dry Tortugas . NRL expects to deliver the Ground Node to Ismoralda Key in October 2009. FY09 continued the third year of providing Ground

Centaur operations at the space station

NASA Technical Reports Server (NTRS)

Porter, J.; Thompson, W.; Bennett, F.; Holdridge, J.

1987-01-01

A study was conducted on the feasibility of using a Centaur vehicle as a testbed to demonstrate critical OTV technologies at the Space Station. Two Technology Demonstration Missions (TDMs) were identified: (1) Accommodations, and (2) Operations. The Accommodations TDM contained: (1) berthing, (2) checkout, maintenance and safing, and (3) payload integration missions. The Operations TDM contained: (1) a cryogenic propellant resupply mission, and (2) Centaur deployment activities. A modified Space Station Co-Orbiting Platform (COP) was selected as the optimum refueling and launch node due to safety and operational considerations. After completion of the TDMs, the fueled Centaur would carry out a mission to actually test deployment and help offset TDM costs. From the Station, the Centaur could carry a single payload in excess of 20,000 pounds to geosynchronous orbit or multiple payloads.

Body Wave and Ambient Noise Tomography of Makushin Volcano, Alaska

NASA Astrophysics Data System (ADS)

Lanza, F.; Thurber, C. H.; Syracuse, E. M.; Ghosh, A.; LI, B.; Power, J. A.

2017-12-01

Located in the eastern portion of the Alaska-Aleutian subduction zone, Makushin Volcano is among the most active volcanoes in the United States and has been classified as high threat based on eruptive history and proximity to the City of Unalaska and international air routes. In 2015, five individual seismic stations and three mini seismic arrays of 15 stations each were deployed on Unalaska island to supplement the Alaska Volcano Observatory (AVO) permanent seismic network. This temporary array was operational for one year. Taking advantage of the increased azimuthal coverage and the array's increased earthquake detection capability, we developed body-wave Vp and Vp/Vs seismic images of the velocity structure beneath the volcano. Body-wave tomography results show a complex structure with the upper 5 km of the crust dominated by both positive and negative Vp anomalies. The shallow high-Vp features possibly delineate remnant magma pathways or conduits. Low-Vp regions are found east of the caldera at approximately 6-9 km depth. This is in agreement with previous tomographic work and geodetic models, obtained using InSAR data, which had identified this region as a possible long-term source of magma. We also observe a high Vp/Vs feature extending between 7 and 12 km depth below the caldera, possibly indicating partial melting, although the resolution is diminished at these depths. The distributed stations allow us to further complement body-wave tomography with ambient noise imaging and to obtain higher quality of Vs images. Our data processing includes single station data preparation and station-pair cross-correlation steps (Bensen et al., 2007), and the use of the phase weighted stacking method (Schimmel and Gallart, 2007) to improve the signal-to-noise ratio of the cross-correlations. We will show surface-wave dispersion curves, group velocity maps, and ultimately a 3D Vs image. By performing both body wave and ambient noise tomography, we provide a high-resolution tomographic image of Makushin Volcano as well as better-constrained earthquake locations, thus enhancing AVO's monitoring and forecasting efforts.

Mantle structure beneath eastern Africa: Evidence for a through going-mantle anomaly and its implications for the origin of Cenozoic tectonism in eastern Africa

NASA Astrophysics Data System (ADS)

Mulibo, G.; Tugume, F.; Julia, J.

2012-12-01

In this study, teleseismic earthquakes recorded on over 60 temporary AfricaArray seismic stations deployed in Uganda, Kenya, Tanzania and Zambia between 2007 and 2011 are used to invert P and S travel time residuals, together with travel time residuals from previous deployments, for a 3D image of mantle wave speeds and for examining relief on transition zone discontinuities using receiver function stacks. Tomographic images reveal a low wave speed anomaly (LWA) that dips to the SW beneath northern Zambia, extending to a depth of at least 900 km. The anomaly appears to be continuous across the transition zone, extending into the lower mantle. Receiver function stacks reveal an average transition zone thickness (TZT) across a wide region extending from central Zambia to the NE through Tanzania and into Kenya, which is ~30-40 km thinner than the global average. These results are not easily explained by models for the origin of the Cenozoic tectonism in eastern Africa that invoke a plume head or small scale convection either by edge flow or passive stretching of the lithosphere. However, the depth extent of the LWA coincident with a thin transition zone is consistent with a model invoking a through-going mantle anomaly beneath eastern Africa that links anomalous upper mantle to the African Superplume anomaly in the lower mantle beneath southern Africa. This finding indicates that geodynamic processes deep in the lower mantle are influencing surface dynamics across the Afro-Arabian rift system.

The ESA-NASA CHOICE Study: Winterover at Concordia Station, Interior Antarctica, A Potential Analog for Spaceflight-Associated Immune Dysregulation

NASA Technical Reports Server (NTRS)

Crucian, B. E.; Stowe, R. P.; Mehta, S. K.; Quiriarte, H.; Pierson, D L.; Sams, C. F.

2010-01-01

For ground-based space physiological research, the choice of terrestrial analog must carefully match the system of interest. Antarctica winter-over at the European Concordia Station is potentially a superior ground-analog for spaceflight-associated immune dysregulation (SAID). Concordia missions consist of prolonged durations in an extreme/dangerous environment, station-based habitation, isolation, disrupted circadian rhythms and international crews. The ESA-NASA CHOICE study assesses innate and adaptive immunity, viral reactivation and stress factors during Concordia winterover deployment. Initial data obtained from the first study deployment (2009 mission; 'n' of 6) will be presented, and logistical challenges regarding analog usage for biological studies will also be discussed. The total WBC increased, and alterations in some peripheral leukocyte populations were observed during winterover at Concordia Station. Percentages of lymphocytes and monocytes increased, and levels of senescent CD8+ T cells were increased during deployment. Transient increases in constitutively activated T cell subsets were observed, at mission time points associated with endemic disease outbreaks. T cell function (early blastogenesis response) was increased near the entry/exit deployment phases, and production of most measured cytokines increased during deployment. Salivary cortisol demonstrated high variability during winterover, but was generally increased. A 2-point circadian rhythm of cortisol measurement (morning/evening) was unaltered during winterover. Perceived stress was mildly elevated during winterover. Other measures, including in-vitro DTH assessment, viral specific T cell number/function and latent herpesvirus reactivation have not yet been completed for the 2009 winterover subjects. Based on the preliminary data, alterations in immune cell distribution and function appear to persist during Antarctic winterover at Concordia Station. Some of these changes are similar to those observed in Astronauts, either during or immediately following spaceflight. Based on the initial immune data and environmental conditions, Concordia winterover may be an appropriate analog for some flight-associated immune changes.

A Dense Small-Scale Seismic Network in the Ngorongoro Conservation Area (Northern Tanzania)

NASA Astrophysics Data System (ADS)

Parisi, L.; Lombardo, L.; Rodriguez-Mustafa, M.; Mai, P. M.

2017-12-01

A temporary deployment consisting of sixteen broadband seismic stations is conducted for the first time in the Ngorongoro Conservation Area (NCA, Northern Tanzania), located at the boundary between the Tanzanian Craton and East African Rift. A deep knowledge of the faulting systems and tectonics of the area is needed to better understand the contribution of the synsedimentary faults to the deposition of the Olduvai and surrounding basins affecting the landscapes of the Homo Habilis first settlements. Complex fault systems have been mapped in the field but their connection, especially at depth, is not well known. A first batch of ten instruments was installed in June 2016. In June 2017 two stations were dismissed and a second batch of six stations was installed in new locations. The current network of fourteen stations will record until May 2018. Stations are equipped with Nanometrics Trillium Compact Posthole 120 s sensor and Centaur digitiser recording continuously at 200 Hz. The whole network covers 1400 km2 and station interspace ranges from 8 to 15 km. We analyse probabilistic power spectra densities of the seismic noise to obtain insights of its origin and test the performances of the stations. Although factories do not exist in the area and most of the stations are far from roads, ambient noise in the range 0.01 - 1 s is relatively high (between -120 dB and -100dB at 0.1 s) probably because of the abundance of livestock living in the NCA. Ambient noise in the period range 1 - 10 s (secondary microseisms) decreases from east to west. Although the main source of the microseisms is located in the Indian Ocean (east of the study area), a contribution from the low period tremors coming from the nearby active volcano Ol Doinyo Lengai (north-east of the study area) is expected. Whereas the longer period noise (10 - 100 s) is very low in the vertical component seismograms, it is higher than the high noise model in the horizontal components for most of the stations. Although this can be due to sensor insulation issues, we find a strong variability even for sensors installed in the same conditions. We also present the first seismicity map of the NCA by using the first year of data. We detect events with ML ranging between 0.7 and 3.0, mostly located south where major fault systems have not been mapped at the surface yet.

The 2010-2011 Microearthquake Swarm in Krýsuvík, SW Iceland: Was it Triggered by Crustal Magma Injection?

NASA Astrophysics Data System (ADS)

Liu, J.; Michael, F.; Hager, B. H.

2013-12-01

Iceland, the on-land continuation of the Mid-Atlantic Ridge, is the result of the interaction between the Mid-Atlantic Ridge and the North-Atlantic mantle plume. The superposition and relative motion of the spreading plate boundary over the mantle plume are manifested by the volcanism and seismicity in Iceland. The Krýsuvík geothermal field is one of the most active geothermal fields in southwest Iceland. In 2010, Massachusetts Institute of Technology, Reykjanes University, Uppsala University, and the Iceland Geosurvey (ISOR) deployed 38 temporary seismic stations on the Reykjanes Peninsula. Using data from 18 of the temporary seismic stations and from 5 stations of the South Iceland Lowland network around Krýsuvík, we captured an earthquake swarm that occurred between November, 2010 and February, 2011. We applied double difference tomography to relocate the events and determine the velocity structure in the region. Activity is clustered around the center of the Krýsuvík volcano system. Our seismic tomography result indicates a low velocity zone at a depth of about 6 km, right under the earthquake swarm. We consider that this low velocity zone contains some crustal magma that may be the thermal source for the geothermal field. At the same time, our relocated events delineate faults above and around this magma chamber. The system is within the stress field of a combination of left-lateral shear and extension; the majority of the strike-slip faults are right-lateral and most dip-slip faults are normal faults. Published geodetic measurements for the time period between 2009 and 2012 show a few centimeters uplift and extension in the area of the seismic swarm. We modeled the observed deformation using the Coulomb 3.3 software (U.S. Geological Survey). Our result indicates that a Mogi source of about 20×10^6 m^3 at a depth of about 6 km, consistent with the location and size of the tomography result, can explain the main deformation. The normal and the right-lateral strike-slip faults that are delineated by the earthquake relocations, consistent with the local stress induced by magma intrusion and the regional stress field caused by the interaction of the spreading plate boundary and mantle plume, explain the observed second order deformation. Our results are consistent with the hypothesis that seismicity in the Krýsuvík area in 2010-2011 might be triggered by magmatic activity.

KSC-98pc1660

NASA Image and Video Library

1998-11-06

Workers in the Space Station Processing Facility watch the Passive Common Berthing Mechanism (PCBM) lifted high to move it over to the Z1 integrated truss structure at right. It will be mated to the Z1 truss, a component of the International Space Station (ISS). The Z1 truss will be used for the temporary installation of the P6 truss segment to the Unity connecting module. The P6 truss segment contains the solar arrays and batteries which will provide early station power. The truss is scheduled to be launched aboard STS-92 in late 1999

Characterization of the 2015 M4.0 Venus, Texas, Earthquake Sequence Using Locally Recorded Seismic Data

NASA Astrophysics Data System (ADS)

Scales, M. M.; DeShon, H. R.; Hayward, C.; Magnani, M. B.; Walter, J. I.; Pratt, T. L.

2015-12-01

We present high-resolution relative earthquake relocations derived using differential time data from waveform cross-correlation and first motion fault plane solutions to characterize the 2015 M4.0 Venus, TX, earthquake sequence. On 7 May 2015, a M4.0 earthquake occurred in Johnson County, TX, south of the Dallas-Fort Worth metroplex. It is the largest event recorded to date in the Fort Worth (Barnett Shale) Basin, which is an active shale gas production area that has been associated with induced earthquakes. The USGS moment tensor indicated normal faulting along NE-SW trending faults and two additional felt aftershocks were reported in the National Earthquake Information Center catalog. Beginning on 11 May 2015, a temporary seismic network was deployed. Over the first week, SMU deployed 13 vertical-component RT125s and 3 USGS NetQuakes instruments. The RT125s were replaced with 7 short-period 3-component instruments provided by IRIS and 4 broadband stations deployed throughout Johnson County by the University of Texas. To date, we have located over 100 events that define a 5 km long normal fault striking 35°NE and dipping ~70°. Events occur in the Precambrian granitic basement at depths of 4-6km. These locations are near the bottom of the Ellenburger Group (~3.5km in depth), which is an Ordovician carbonate platform overlying the basement and is often used for wastewater disposal. Five large volume injection wells operate within 10km of the earthquake sequence and inject very near, if not through, the Ellenburger-basement contact. These wells were temporarily shut down by the Texas Railroad Commission for testing but were reported at the time to have no causal effect on the earthquake activity. We explore temporal and spatial correlations between seismicity, wastewater injection data and subsurface fault data to better understand the cause of the Venus sequence.

Nanoracks CUBESAT launcher operations

NASA Image and Video Library

2014-08-20

ISS040-E-103340 (20 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer (upper right) releases a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at center. A blue and white part of Earth and the blackness of space provide the backdrop for the scene.

Payload Bay of Endeavour

NASA Image and Video Library

2008-11-26

S126-E-11974 (26 Nov. 2008) --- Backdropped against white clouds, the aft section of Endeavour's cargo bay, now holding the multipurpose logistics module Leonardo, is featured in this digital still photo, framed through a window on the International Space Station. Endeavour and the orbital outpost have been docked for almost two weeks while their crews have joined efforts in home improvement on the station and other work. Astronauts Donald Pettit and Shane Kimbrough, operating the space station's robot arm from inside the Destiny laboratory module, detached the Leonardo cargo canister from its temporary parking place on the station a few hours earlier and re-berthed it in the cargo bay.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044887 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044889 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044890 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it deploys a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

Development, deployment, and evaluation of a remote monitoring system and a virtual weigh station : final report.

DOT National Transportation Integrated Search

2005-11-01

In order to extend commercial vehicle enforcement coverage to routes that are not monitored by fixed weigh stations, Kentucky has developed and implemented a Remote Monitoring System (RMS) and a Virtual Weight Station (VWS). The RMS captures images o...

Improving highway advisory radio predictability and performance

DOT National Transportation Integrated Search

2011-01-01

Highway Advisory Radio (HAR) stations, sometimes referred to as Travelers Information Stations (TIS), : allow highway agencies to broadcast important messages about traffic, weather and roadway conditions to : motorists. Caltrans has deployed HAR ...

41 CFR 302-6.305 - What factors should we consider in determining whether quarters are temporary?

Code of Federal Regulations, 2011 CFR

2011-07-01

... Property Management Federal Travel Regulation System RELOCATION ALLOWANCES PERMANENT CHANGE OF STATION (PCS..., the employee's expressions of intent, attempts to secure a permanent dwelling, and the length of time...

41 CFR 302-6.307 - What factors should we consider in determining whether quarters are temporary?

Code of Federal Regulations, 2014 CFR

2014-07-01

... Property Management Federal Travel Regulation System RELOCATION ALLOWANCES PERMANENT CHANGE OF STATION (PCS..., the employee's expressions of intent, attempts to secure a permanent dwelling, and the length of time...

41 CFR 302-6.307 - What factors should we consider in determining whether quarters are temporary?

Code of Federal Regulations, 2012 CFR

2012-07-01

... Property Management Federal Travel Regulation System RELOCATION ALLOWANCES PERMANENT CHANGE OF STATION (PCS..., the employee's expressions of intent, attempts to secure a permanent dwelling, and the length of time...

41 CFR 302-6.307 - What factors should we consider in determining whether quarters are temporary?

Code of Federal Regulations, 2013 CFR

2013-07-01

... Property Management Federal Travel Regulation System RELOCATION ALLOWANCES PERMANENT CHANGE OF STATION (PCS..., the employee's expressions of intent, attempts to secure a permanent dwelling, and the length of time...

41 CFR 302-6.305 - What factors should we consider in determining whether quarters are temporary?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Property Management Federal Travel Regulation System RELOCATION ALLOWANCES PERMANENT CHANGE OF STATION (PCS..., the employee's expressions of intent, attempts to secure a permanent dwelling, and the length of time...

Close-up view of Sunflower Seeds

NASA Image and Video Library

2013-11-04

ISS037-E-026274 (4 Nov. 2013) --- A two-day old sunflower sprout is being closely monitored in its temporary home inside a plastic bag by the Expedition 37 crew members onboard the Earth-orbiting International Space Station.

A study of space station needs, attributes and architectural options

NASA Technical Reports Server (NTRS)

1983-01-01

The mission requirements, economic benefits, and time table of deployment of the space station are discussed. It is concluded that: (1) mission requirements overwhelmingly support the need for a space station; (2) a single space station is the way to begin; (3) the space station must evolve its capability; (4) the orbit transfer vehicle aspect of the space station will provide significant economic benefit; and (5) an early, affordable, effective way to start the space station program is needed.

Update on Progress of Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS) - Cyclops

NASA Technical Reports Server (NTRS)

Newswander, Daniel; Smith, James P.; Lamb, Craig R.; Ballard, Perry G.

2014-01-01

The Space Station Integrated Kinetic Launcher for Orbital Payload Systems (SSIKLOPS), known as "Cyclops" to the International Space Station (ISS) community, was introduced last August (2013) during Technical Session V: From Earth to Orbit of the 27th Annual AIAA/USU Conference on Small Satellites. Cyclops is a collaboration between the NASA ISS Program, NASA Johnson Space Center Engineering, and Department of Defense (DoD) Space Test Program (STP) communities to develop a dedicated 50-100 kg class ISS small satellite deployment system. This paper will address the progress of Cyclops through its fabrication, assembly, flight certification, and on-orbit demonstration phases. It will also go into more detail regarding its anatomy, its satellite deployment concept of operations, and its satellite interfaces and requirements. Cyclops is manifested to fly on Space-X 4 which is currently scheduled in July 2014 with its initial satellite deployment demonstration of DoD STP's SpinSat and UT/TAMU's Lonestar satellites being late summer or fall of 2014.

Scientific tradeoffs in pinhole/occulter facility accommodation

NASA Technical Reports Server (NTRS)

Hudson, Hugh S.

1988-01-01

The Pinhole/Occulter Facility (P/OF) consists of state-of-the-art instruments for the study of particle acceleration in the solar corona, and uses a large structure to obtain very high angular resolution. P/OF has been studied in the past as an attached payload for the Space Shuttle, and has been the subject of study by a NASA Science Working Group (P/OFSWG). Appendix A lists various technical studies and reports carried out under the auspices of P/OFSWG and the Program Development Office of NASA Marshall Space Flight Center. Under the rationalization of NASA flight opportunities following the Challenger disaster, and the beginning of the Space Station Freedom program, the sortie-mode deployment of P/OF seemed less efficient and desirable. Thus, NASA decided to reconsider P/OF for deployment on the Space Station Freedom. The technical studies for this deployment continue at the present and will evolve as our knowledge of Space Station architecture and capabilities increase. MSFC contracted with Teledyne Brown Engineering for these technical studies.

International Space Station (ISS)

NASA Image and Video Library

1994-04-20

An artist's concept of a fully deployed International Space Station (ISS) Alpha. The ISS-A is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experiments.

Peace and war: trajectories of posttraumatic stress disorder symptoms before, during, and after military deployment in Afghanistan.

PubMed

Berntsen, Dorthe; Johannessen, Kim B; Thomsen, Yvonne D; Bertelsen, Mette; Hoyle, Rick H; Rubin, David C

2012-12-01

In the study reported here, we examined posttraumatic stress disorder (PTSD) symptoms in 746 Danish soldiers measured on five occasions before, during, and after deployment to Afghanistan. Using latent class growth analysis, we identified six trajectories of change in PTSD symptoms. Two resilient trajectories had low levels across all five times, and a new-onset trajectory started low and showed a marked increase of PTSD symptoms. Three temporary-benefit trajectories, not previously described in the literature, showed decreases in PTSD symptoms during (or immediately after) deployment, followed by increases after return from deployment. Predeployment emotional problems and predeployment traumas, especially childhood adversities, were predictors for inclusion in the nonresilient trajectories, whereas deployment-related stress was not. These findings challenge standard views of PTSD in two ways. First, they show that factors other than immediately preceding stressors are critical for PTSD development, with childhood adversities being central. Second, they demonstrate that the development of PTSD symptoms shows heterogeneity, which indicates the need for multiple measurements to understand PTSD and identify people in need of treatment.

Analyzing mobile WiMAX base station deployment under different frequency planning strategies

NASA Astrophysics Data System (ADS)

Salman, M. K.; Ahmad, R. B.; Ali, Ziad G.; Aldhaibani, Jaafar A.; Fayadh, Rashid A.

2015-05-01

The frequency spectrum is a precious resource and scarce in the communication markets. Therefore, different techniques are adopted to utilize the available spectrum in deploying WiMAX base stations (BS) in cellular networks. In this paper several types of frequency planning techniques are illustrated, and a comprehensive comparative study between conventional frequency reuse of 1 (FR of 1) and fractional frequency reuse (FFR) is presented. These techniques are widely used in network deployment, because they employ universal frequency (using all the available bandwidth) in their base station installation/configuration within network system. This paper presents a network model of 19 base stations in order to be employed in the comparison of the aforesaid frequency planning techniques. Users are randomly distributed within base stations, users' resource mapping and their burst profile selection are based on the measured signal to interference plus-noise ratio (SINR). Simulation results reveal that the FFR has advantages over the conventional FR of 1 in various metrics. 98 % of downlink resources (slots) are exploited when FFR is applied, whilst it is 81 % at FR of 1. Data rate of FFR has been increased to 10.6 Mbps, while it is 7.98 Mbps at FR of 1. The spectral efficiency is better enhanced (1.072 bps/Hz) at FR of 1 than FFR (0.808 bps/Hz), since FR of 1 exploits all the Bandwidth. The subcarrier efficiency shows how many data bits that can be carried by subcarriers under different frequency planning techniques, the system can carry more data bits under FFR (2.40 bit/subcarrier) than FR of 1 (1.998 bit/subcarrier). This study confirms that FFR can perform better than conventional frequency planning (FR of 1) which made it a strong candidate for WiMAX BS deployment in cellular networks.

Multi-parameter observations in the Ibero-Moghrebian region: the Western Mediterranean seismic network (WM) and ROA GPS geodynamic network

NASA Astrophysics Data System (ADS)

Pazos, Antonio; Martín Davila, José; Buforn, Elisa; Gárate Pasquín, Jorge; Catalán Morollón, Manuel; Hanka, Winfried; Udías, Agustín.; Benzzeghoud, Mourad; Harnafi, Mimoun

2010-05-01

The plate boundary between Eurasia and Africa plates crosses the called "Ibero-Maghrebian" region from the San Vicente Cape (SW Portugal) to Tunisia including the South of Iberia, Alboran Sea, and northern Morocco and Algeria. In this area, the convergence, with a low rate, is accommodated over a wide and diffuse deformation zone, characterized by a significant and widespread moderate seismic activity [Buforn et al., 1995], and the occurrence of large earthquakes is separated by long time intervals. Since more than hundred years ago San Fernando Naval Observatory (ROA), in collaboration with other Institutes, has deployed different geophysical and geodetic equipment in the Southern Spain - North-western Africa area in order to study this broad deformation zone. Currently a Broad Band seismic net (Western Mediterranean, WM net) is deployed, in collaboration with other institutions, around the Gulf of Cádiz and the Alboran sea, with stations in the South of Iberia and in North Africa (at Spanish places and Morocco), together with the seismic stations a permanent geodetic GPS net is co-installed at the same sites. Also, other geophysical instruments have been installed: a Satellite Laser Ranging (SLR) station at San Fernando Observatory Headquarter, a Geomagnetic Observatory in Cádiz bay area and some meteorological stations. These networks have been recently improved with the deployment of a new submarine and on-land geophysical observatory in the Alboran island (ALBO Observatory), where a permanent GPS, a meteorological station were installed on land and a permanent submarine observatory in 50 meters depth was also deploy in last October (with a broad band seismic sensor, a 3 C accelerometer and a DPG). This work shows the present status and the future plans of these networks and some results.

Spatial and temporal trends in water quality in a Mediterranean temporary river impacted by sewage effluents.

PubMed

David, Arthur; Tournoud, Marie-George; Perrin, Jean-Louis; Rosain, David; Rodier, Claire; Salles, Christian; Bancon-Montigny, Chrystelle; Picot, Bernadette

2013-03-01

This paper analyzes how changes in hydrological conditions can affect the water quality of a temporary river that receives direct inputs of sewage effluents. Data from 12 spatial surveys of the Vène river were examined. Physico-chemical parameters, major ion, and nutrient concentrations were measured. Analyses of variance (ANOVA) and multivariate analyses were performed. ANOVA revealed significant spatial differences for conductivity and major ion but no significant spatial differences for nutrient concentrations even if higher average concentrations were observed at stations located downstream from sewage effluent discharge points. Significant temporal differences were observed among all the parameters. Karstic springs had a marked dilution effect on the direct disposal of sewage effluents. During high-flow periods, nutrient concentrations were high to moderate whereas nutrient concentrations ranged from moderate to bad at stations located downstream from the direct inputs of sewage effluents during low-flow periods. Principal component analysis showed that water quality parameters that explained the water quality of the Vène river were highly dependent on hydrological conditions. Cluster analysis showed that when the karstic springs were flowing, water quality was homogeneous all along the river, whereas when karstic springs were dry, water quality at the monitoring stations was more fragmented. These results underline the importance of considering hydrological conditions when monitoring the water quality of temporary rivers. In view of the pollution observed in the Vène river, "good water chemical status" can probably only be achieved by improving the management of sewage effluents during low-flow periods.

EarthScope's Transportable Array in Alaska and Western Canada

NASA Astrophysics Data System (ADS)

Enders, M.; Miner, J.; Bierma, R. M.; Busby, R.

2015-12-01

EarthScope's Transportable Array (TA) in Alaska and Canada is an ongoing deployment of 261 high quality broadband seismographs. The Alaska TA is the continuation of the rolling TA/USArray deployment of 400 broadband seismographs in the lower 48 contiguous states and builds on the success of the TA project there. The TA in Alaska and Canada is operated by the IRIS Consortium on behalf of the National Science Foundation as part of the EarthScope program. By Sept 2015, it is anticipated that the TA network in Alaska and Canada will be operating 105 stations. During the summer 2015, TA field crews comprised of IRIS and HTSI station specialists, as well as representatives from our partner agencies the Alaska Earthquake Center and the Alaska Volcano Observatory and engineers from the UNAVCO Plate Boundary Observatory will have completed a total of 36 new station installations. Additionally, we will have completed upgrades at 9 existing Alaska Earthquake Center stations with borehole seismometers and the adoption of an additional 35 existing stations. As the array doubles in Alaska, IRIS continues to collaborate closely with other network operators, universities and research consortia in Alaska and Canada including the Alaska Earthquake Center (AEC), the Alaska Volcano Observatory (AVO), the UNAVCO Plate Boundary Observatory (PBO), the National Tsunami Warning Center (NTWC), Natural Resources Canada (NRCAN), Canadian Hazard Information Service (CHIS), the Yukon Geologic Survey (YGS), the Pacific Geoscience Center of the Geologic Survey, Yukon College and others. During FY14 and FY15 the TA has completed upgrade work at 20 Alaska Earthquake Center stations and 2 AVO stations, TA has co-located borehole seismometers at 5 existing PBO GPS stations to augment the EarthScope observatory. We present an overview of deployment plan and the status through 2015. The performance of new Alaska TA stations including improvements to existing stations is described.

NASA Global GNSS Network (GGN) Status and Plans

NASA Astrophysics Data System (ADS)

Doelger, S.; Sklar, J.; Blume, F.; Meertens, C. M.; Mattioli, G. S.

2015-12-01

UNAVCO, in conjunction with JPL, is responsible for monitoring the 62 GNSS permanent stations, which include 88 GPS receivers, which comprise the NASA Global GNSS Network (GGN). These sites represent approximately 16% of the ~400 International GNSS Service (IGS) stations, and they provide a globally distributed GNSS network to support NASA operations and its commitments to GGOS. UNAVCO provides data flow monitoring, trouble-shooting, station installation, maintenance, as well as engineering services to improve the capabilities and performance of station infrastructure. Activities this past year include the installation of a geodetic quality wellhead monument for the new SEY2 station to replace SEY1, which is mounted on a UCSD seismic station in the Seychelles Islands. SEY1 will be removed soon to accommodate planned maintenance and upgrades by UCSD. Data from both SEY1 and SEY2 are being collected concurrently until maintenance begins. MRTG (Multi Router Traffic Grapher), a tool to aid in characterizing bandwidth usage and to identify communications problems, is now being used to monitor data throughput at 7 stations where VSAT or radio telemetry are used, including: ABPO; AREQ; FALK; GUAM; HARV; ISPA; QUIN; and STHL. Aging computers are being replaced with new hardware running Linux CentOS. These are semi-ruggedized low power solid-state systems built to endure challenging environments. With the aid of on-site collaborators, systems are now deployed at: FALK; CUSV; KELY; STHL; SANT; and ZAMB. Last, 4 new GPS stations were deployed for NASA's Space Geodesy Project (SGP); three of which (KOKF, KOKG, and KOKR) are located at Koke'e Park Geophysical Observatory on Kauai, Hawai'i, and HAL1 at the Haleakala observatory complex on Maui, Hawai'i. A campaign system was set up at Koke'e in order to sample data quality to determine if an additional station would be viable. Planning is ongoing for deployment of several new stations next year at McDonald Observatory (TX).

Seismic and thermal structure of the crust and uppermost mantle beneath Antarctica from inversion of multiple seismic datasets

NASA Astrophysics Data System (ADS)

Wiens, D.; Shen, W.; Anandakrishnan, S.; Aster, R. C.; Gerstoft, P.; Bromirski, P. D.; Dalziel, I.; Hansen, S. E.; Heeszel, D.; Huerta, A. D.; Nyblade, A.; Stephen, R. A.; Wilson, T. J.; Winberry, J. P.; Stern, T. A.

2017-12-01

Since the last decade of the 20th century, over 200 broadband seismic stations have been deployed across Antarctica (e.g., temporary networks such as TAMSEIS, AGAP/GAMSEIS, POLENET/ANET, TAMNNET and RIS/DRIS by U.S. geoscientists as well as stations deployed by Japan, Britain, China, Norway, and other countries). In this presentation, we discuss our recent efforts to build reference crustal and uppermost mantle shear velocity (Vs) and thermal models for continental Antarctica based on those seismic arrays. By combing the high resolution Rayleigh wave dispersion maps derived from both ambient noise and teleseismic earthquakes, together with P receiver function waveforms, we develop a 3-D Vs model for the crust and uppermost mantle beneath Central and West Antarctica to a depth of 200 km. Additionally, using this 3-D seismic model to constrain the crustal structure, we re-invert for the upper mantle thermal structure using the surface wave data within a thermodynamic framework and construct a 3-D thermal model for the Antarctic lithosphere. The final product, a high resolution thermal model together with associated uncertainty estimates from the Monte Carlo inversion, allows us to derive lithospheric thickness and surface heat flux maps for much of the continent. West Antarctica shows a much thinner lithosphere ( 50-90 km) than East Antarctica ( 130-230 km), with a sharp transition along the Transantarctic Mountains (TAM). A variety of geological features, including a slower/hotter but highly heterogeneous West Antarctica and a much faster/colder East Antarctic craton, are present in the 3-D seismic/thermal models. Notably, slow seismic velocities observed in the uppermost mantle beneath the southern TAM are interpreted as a signature of lithospheric foundering and replacement with hot asthenosphere. The high resolution image of these features from the 3-D models helps further investigation of the dynamic state of Antarctica's lithosphere and underlying asthenosphere and provides key constraints on the interaction between the solid Earth and the West Antarctic Ice Sheet.

Induced Seismicity in the Bakken: Much Ado about Almost Nothing

NASA Astrophysics Data System (ADS)

Frohlich, C.; Walter, J. I.; Gale, J.

2014-12-01

This study investigates possible links between seismicity and wastewater injection in the Williston Basin and Bakken Formation in North Dakota and Montana. To identify Bakken earthquakes we analyzed seismic records collected by the EarthScope USArray temporary network of seismograph stations, deployed on a grid with 70-km spacing. During the September 2008 - May 2011 study period we identified only nine earthquakes; of these only three were near injection wells. Thus, possibly triggered earthquakes are rarer near injection wells in the Bakken than in the Barnett Shale of Texas, or in central Oklahoma. The reason why Bakken earthquakes are so scarce is unclear. In many respects the Bakken/Williston region is similar to the Barnett Shale/Fort Worth Basin of Texas. In both regions injection volumes increased significantly in late 2007, and both areas have low levels of natural seismicity. Yet, in Johnson and Tarrant counties in the Barnett, earthquakes near injection wells were numerous; in the Bakken and elsewhere in the Barnett, earthquakes near wells were scarce. An important result of these surveys is that the relationship between seismicity and injection/production activities varies considerably in different geographic areas. In the Bakken and western counties of Texas' Barnett Shale, there is almost no seismic activity near injection wells. In Oklahoma, Arkansas, parts of the Barnett, and near Timpson in east Texas, there are earthquakes associated with high-volume injection wells. In the Eagle Ford of Texas earthquakes are associated primarily with production (not injection). And near Snyder, TX, recent earthquakes are associated with CO2injection. This variability in response to injection complicates efforts to craft uniform policies or regulations to mitigate potential seismic hazards associated with injection practices. At a minimum it suggests that within particular geographic regions it is important to survey the relationship between seismicity and injection before considering possible policy responses or regulations. For these regional surveys, the records collected during the two-year deployment of USArray stations are valuable, although these may need to be augmented by continuing coverage. Figure: Earthquakes, explosions, injection wells, and coal mines in the Bakken (shaded area).

Hidden Rift Structure Beneath a Thick Sedimentary Basin in the Niigata Region, Japan

NASA Astrophysics Data System (ADS)

Takeda, T.; Enescu, B.; Asano, Y.; Obara, K.; Sekiguchi, S.

2010-12-01

Niigata region is located in a high-strain-rate zone, along the easternmost margin of the back-arc basin of the Sea of Japan (Sagiya et al., 2000, Okamura et al., 1995). In this region, two M6.8 inland earthquakes with reverse fault type focal mechanism, having NW-SE compression, occurred in 2004 and 2007. The reverse fault system may indicate present reactivation of the rift structure formed as a result of normal faulting when the Sea of Japan opened in the Miocene (Sato, 1994). Therefore, imaging the spatial extent of the rift structure is important to reveal the seismotectonics and occurrence mechanism of inland earthquakes. To resolve the fine structure beneath the Niigata region, we have installed a dense temporary network of 300 seismic stations and performed a regional tomography analysis. The temporary seismic network was designed with a multi-scale station spacing of 3 to 5 km in and around the aftershock areas of the two large earthquakes, and of ~10 km for the surrounding region. The 3D velocity tomography analysis and relocation of earthquakes were performed using the tomoDD software (Zhang and Thurber, 2003). We used 777 events that occurred after the installation of the temporary network and 703 events that were recorded only by the permanent seismic network (Hi-net) before the temporary network deployment. The initial 3D velocity model was constructed by using the 3D shallow velocity structure provided by the “Japan Seismic Hazard Information Station” (J-SHIS; Fujiwara et al., 2009) of NIED. The horizontal and vertical grid spacing were of 5 ~ 10 km and 2 ~ 4 km, respectively. The tomography analysis enabled us to delineate the fine subsurface structure. The high and low velocity pattern corresponds well to the Bouguer gravity anomalies mapped in the region. The velocity model shows a wide and relatively low velocity (< 5 km/sec for the P-wave velocity) band extending in a NE-SW direction. The band widens and narrows along its extent. The thickness of the low-velocity region varies from place to place and exceeds 7 km in some parts. The surface of the basement rock below the low velocity band is fairly undulated, showing in some places a stair-like structure. Most of the earthquakes occurred in the basement rocks. The aftershocks of the 2004 and 2007 Niigata earthquakes occurred on the flanks of the lower velocity band. Kato et al. (2009) suggested that in the two aftershock areas the undulation of the basement rock surface was formed from multiple rift structures. According to our tomography results, the undulation structure is extensively found below the low-velocity band, which indicates that ancient, hidden rift structures are widely distributed. Some of these structures show micro-earthquake activity, however they do not correspond to the recognized active fault traces. The reactivation of deep rift structures covered with thick sediments may have not been fully detected. Therefore, mapping of the hidden rift structure helps mitigating the earthquake hazards in this high strain-rate and high seismic activity region.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009334 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009458 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044883 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station as it begins the deployment of a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

NanoRacks CubeSat Deployment

NASA Image and Video Library

2014-02-11

ISS038-E-044994 (11 Feb. 2014) --- The Small Satellite Orbital Deployer (SSOD), in the grasp of the Kibo laboratory robotic arm, is photographed by an Expedition 38 crew member on the International Space Station prior to the deployment of a set of NanoRacks CubeSats. The CubeSats program contains a variety of experiments such as Earth observations and advanced electronics testing.

Analytical investigation of the dynamics of tethered constellations in Earth orbit (phase 2)

NASA Technical Reports Server (NTRS)

Lorenzini, E.; Arnold, D. A.; Grossi, M. D.; Gullahorn, G. E.

1985-01-01

The deployment maneuver of three axis vertical constellations with elastic tethers is analyzed. The deployment strategy devised previously was improved. Dampers were added to the system. Effective algorithms for damping out the fundamental vibrational modes of the system were implemented. Simulations of a complete deployment and a subsequent station keeping phase of a three mass constellation is shown.

Small Cube Satellite Deploy

NASA Image and Video Library

2013-11-19

ISS038-E-003874 (19 Nov. 2013) --- Three nanosatellites, known as Cubesats, are deployed from a Small Satellite Orbital Deployer (SSOD) attached to the Kibo laboratory's robotic arm at 7:10 a.m. (EST) on Nov. 19, 2013. Japan Aerospace Exploration Agency astronaut Koichi Wakata, Expedition 38 flight engineer, monitored the satellite deployment while operating the Japanese robotic arm from inside Kibo. The Cubesats were delivered to the International Space Station Aug. 9, aboard Japan's fourth H-II Transfer Vehicle, Kounotori-4.

­The Carnegie Quick Deploy Box (QDB) for use with broadband and intermediate period sensors

NASA Astrophysics Data System (ADS)

Wagner, L. S.; Roman, D.; Bartholomew, T.; Golden, S.; Schleigh, B.

2017-12-01

Recent data processing advances have increased the call for dense recordings of teleseismic data. However, traditional broadband field installations typically comprise 1) a sensor vault 2) a field box to hold the recording and power systems, and 3) a solar panel mount. The construction of these installations is time consuming and requires bulky construction materials, limiting the number of stations that can be installed from a single vehicle without repeated trips to a storage facility. Depending on the deployment location, watertight containers for both vault and field box can be difficult to find, resulting in a loss of data due to flooding. Recent technological improvements have made possible the direct burial of sensors (no vault required) and a reduction in the size of the solar panels needed to run a station. With support from the Brinson Foundation, we take advantage of these advances to create a field box/shipping container that will greatly simplify these types of seismic deployments. The goal of the Carnegie Quick Deploy Box (QDB) is to have everything needed for an intermediate period station install (except battery and shovel) contained in a single box for shipment, and to be able to leave everything (except the shovel) in that box when the station is deployed. The box is small enough ( 13"x13"x21") and lightweight enough (< 35 lbs) to be checked as airline luggage. The solar panel mount can be attached securely to the top of the box, but it can also be pole mounted with U-bolts or hose clamps. The sensor can be direct-buried. The sensor cable and solar panel cable plug into watertight bulkhead-fitted plugs on the outside of the box that are in turn plugged into the digitizer and power regulator inside the box. Our prototype boxes (Pelican Cases) have proved watertight when submerged for days. This equipment has been tested in Alaska in winter and Nicaragua in summer without failure due to flooding or power. The cost for parts for a single box (not including sensor cable, sensor, or digitizer) is $500. The setup is simple, and can be completed in a matter of minutes once the sensor is installed. QDBs such as ours will make possible a dramatic increase in the number of stations that can be installed, while also significantly decreasing the cost of deployment per station by reducing vehicle time, fuel, personnel time, and shipping costs.

Parametric analysis and temperature effect of deployable hinged shells using shape memory polymers

NASA Astrophysics Data System (ADS)

Tao, Ran; Yang, Qing-Sheng; He, Xiao-Qiao; Liew, Kim-Meow

2016-11-01

Shape memory polymers (SMPs) are a class of intelligent materials, which are defined by their capacity to store a temporary shape and recover an original shape. In this work, the shape memory effect of SMP deployable hinged shell is simulated by using compiled user defined material subroutine (UMAT) subroutine of ABAQUS. Variations of bending moment and strain energy of the hinged shells with different temperatures and structural parameters in the loading process are given. The effects of the parameters and temperature on the nonlinear deformation process are emphasized. The entire thermodynamic cycle of SMP deployable hinged shell includes loading at high temperature, load carrying with cooling, unloading at low temperature and recovering the original shape with heating. The results show that the complicated thermo-mechanical deformation and shape memory effect of SMP deployable hinge are influenced by the structural parameters and temperature. The design ability of SMP smart hinged structures in practical application is prospected.

Crustal Structure Beneath the Gulf of ST. Lawrence, Atlantic Canada, from Ambient Seismic Noise Tomography

NASA Astrophysics Data System (ADS)

Kuponiyi, A.; Kao, H.; Cassidy, J. F.; Spence, G.

2013-12-01

The Gulf of St. Lawrence (GSL), located north of the southwest-northeast trending Appalachian mountain in eastern Canada, is a major sedimentary basin with huge potentials for hydrocarbon accumulation. Important questions about the geometry and evolution of the crustal and basin structure beneath the gulf are yet to be answered. To address these issues, the Geological Survey of Canada (GSC) with support from the Portable Observatories for Lithospheric Analysis and Research Investigating Seismicity (POLARIS) deployed a temporary array of broadband seismic stations in the GSL region between October 2005 and October 2008. Combined with the permanent stations of the Canadian National Seismograph Network (CNSN) in the region, the station density is sufficient for detailed seismic tomography inversion. In this study, we investigate the upper crustal structure beneath the gulf using 3 years of continuous ambient noise waveforms recorded at 25 (POLARIS and CNSN) stations around the GSL. Cross-correlation functions of the vertical component of the ambient noise wavefield for simultaneously recording station pairs (corresponding to inter-station Green's functions) are computed and analyzed using the frequency-time analysis method. Dispersion curves are measured and Rayleigh wave group velocities are subsequently extracted for periods between 2 and 20s, which are periods sensitive to the upper crustal structures. Preliminary results from the dispersion measurements indicate that mean group velocities in the region range from 2.8 to 3.2 km/s across the range of period specified. 2-D group velocity distribution for each period is determined by linearized inversion of the dispersion data. Our tomography results show prominent lateral velocity variation. Low velocity anomalies are observed at shorter periods (up to ~10 s) which correspond to the sedimentary structures at shallow depths (between 5-10 km), whereas the characteristics of upper crustal structures are shown by velocity anomalies at longer periods. Our results show striking similarities with the tomographic images obtained in the previous Canada-wide ambient noise analysis for areas where both studies overlap and are also consistent with results from receiver function and active seismic profiling studies previously done in the region. A detailed inversion of the 3-D shear velocity structure will be conducted to appropriately delineate the thickness and seismic velocity of the composite geologic units.

Shear Wave Velocity Structure beneath the African-Anatolian Subduction Zone in Southwestern Turkey from Inversions of Rayleigh Waves

NASA Astrophysics Data System (ADS)

Teoman, U. M.; Sandvol, E. A.; Kahraman, M.; Sahin, S.; Turkelli, N.

2011-12-01

The ongoing subduction of the African Plate under western Anatolia results in a highly complex tectonic structure especially beneath Isparta Angle (IA) and the surroundings where the Hellenic and Cyprian slabs with different subduction geometries intersect. The primary objective is to accurately image the lithospheric structure at this convergent plate boundary and further understand the reasons responsible for the active deformation. Data was gathered from a temporary seismic network consisting of 10 broadband stations that was installed in August 2006 with the support from University of Missouri and nine more stations deployed in March 2007 with the support from Bogazici Research Fund (project ID:07T203). In addition, 21 permanent stations of Kandilli Observatory and Earthquake Research Institute (KOERI) and two from Süleyman Demirel University (SDU) together with five stations from IRIS/Geofon Network were also included to extend the station coverage. We used earthquakes in a distance range of 30-120 degrees with body wave magnitudes larger than 5.5. Depending on the signal to noise ratio, azimuthal coverage of events, and coherence from station, 81 events provided high-quality data for our analysis. The distribution of events shows a good azimuthal coverage, which is important for resolving both lateral heterogeneity and azimuthal anisotropy. We adopted a two-plane-wave inversion technique of Forsyth and Li (2003) to simultaneously solve for the incoming wave field and phase velocity. This relatively simpler representation of a more complex wavefield provided quite stable patterns of amplitude variations in many cases. To begin with, an average phase velocity dispersion curve was obtained and used as an input for tomographic inversions. Two-dimensional tomographic maps of isotropic and azimuthally anisotropic phase velocity variations were generated. Phase velocities can only tell us integrated information about the upper mantle. Furthermore, we inverted phase velocities for shear wave velocities (Saito,1988) in order to obtain direct information at a depth range of 30-300 km that can be interpreted in terms of major tectonic processes such as extension, slab detachment/tearing, STEP faults, volcanism, temperature anomalies, the presence of melt or dissolved water, etc. Resulting tomograms along horizontal and vertical depth sections provided valuable insights on the crustal and upper mantle structure beneath Southwestern Turkey down to almost 300 km.

41 CFR 301-50.4 - May I be granted an exception to the required use of TMS or ETS once my agency has fully deployed...

Code of Federal Regulations, 2010 CFR

2010-07-01

... an unreasonable burden on mission accomplishment (e.g., emergency travel is involved and TMS/ETS is... Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES ARRANGING FOR TRAVEL SERVICES, PAYING TRAVEL EXPENSES, AND CLAIMING REIMBURSEMENT 50-ARRANGING FOR...

41 CFR 301-50.4 - May I be granted an exception to the required use of TMS or ETS once my agency has fully deployed...

Code of Federal Regulations, 2011 CFR

2011-07-01

... an unreasonable burden on mission accomplishment (e.g., emergency travel is involved and TMS/ETS is... Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES ARRANGING FOR TRAVEL SERVICES, PAYING TRAVEL EXPENSES, AND CLAIMING REIMBURSEMENT 50-ARRANGING FOR...

41 CFR 301-73.102 - May we grant a traveler an exception from required use of TMS or ETS once we have fully deployed...

Code of Federal Regulations, 2010 CFR

2010-07-01

...: (1) Such use would result in an unreasonable burden on mission accomplishment (e.g., emergency travel...-73.102 Section 301-73.102 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES AGENCY RESPONSIBILITIES 73-TRAVEL PROGRAMS eTravel Service and Travel...

41 CFR 301-73.102 - May we grant a traveler an exception from required use of TMS or ETS once we have fully deployed...

Code of Federal Regulations, 2011 CFR

2011-07-01

...: (1) Such use would result in an unreasonable burden on mission accomplishment (e.g., emergency travel...-73.102 Section 301-73.102 Public Contracts and Property Management Federal Travel Regulation System TEMPORARY DUTY (TDY) TRAVEL ALLOWANCES AGENCY RESPONSIBILITIES 73-TRAVEL PROGRAMS eTravel Service and Travel...

Global Precipitation Measurement (GPM) and International Space Station (ISS) Coordination for Cubesat Deployments

NASA Technical Reports Server (NTRS)

Pawloski, James H.; Aviles, Jorge; Myers, Ralph; Parris, Joshua; Corley, Bryan; Hehn, Garrett; Pascucci, Joseph

2016-01-01

This paper describes the specific problem of collision threat to GPM and risk to ISS CubeSat deployment and the process that was implemented to keep both missions safe from collision and maximize their project goals.

Autonomous Adaptive Low-Power Instrument Platform (AAL-PIP) for remote high latitude geospace data collection

NASA Astrophysics Data System (ADS)

Clauer, C. R.; Kim, H.; Deshpande, K.; Xu, Z.; Weimer, D.; Musko, S.; Crowley, G.; Fish, C.; Nealy, R.; Humphreys, T. E.; Bhatti, J. A.; Ridley, A. J.

2014-06-01

We present the development considerations and design for ground based instrumentation that is being deployed on the East Antarctic Plateau along a 40° magnetic meridian chain to investigate interhemispheric magnetically conjugate geomagnetic coupling and other space weather related phenomena. The stations are magnetically conjugate to geomagnetic stations along the west coast of Greenland. The autonomous adaptive low-power instrument platforms being deployed in the Antarctic are designed to operate unattended in remote locations for at least 5 years. They utilize solar power and AGM storage batteries for power, two-way Iridium satellite communication for data acquisition and program/operation modification, support fluxgate and induction magnetometers as well as dual-frequency gps receiver and an HF radio experiment. Size and weight considerations are considered to enable deployment by a small team using small aircraft. Considerable experience has been gained in the development and deployment of remote polar instrumentation that is reflected in the present generation of instrumentation discussed here. We conclude with the lessons learned from our experience in the design, deployment and operation of remote polar instrumentation.

An autonomous adaptive low-power instrument platform (AAL-PIP) for remote high-latitude geospace data collection

NASA Astrophysics Data System (ADS)

Clauer, C. R.; Kim, H.; Deshpande, K.; Xu, Z.; Weimer, D.; Musko, S.; Crowley, G.; Fish, C.; Nealy, R.; Humphreys, T. E.; Bhatti, J. A.; Ridley, A. J.

2014-10-01

We present the development considerations and design for ground-based instrumentation that is being deployed on the East Antarctic Plateau along a 40° magnetic meridian chain to investigate interhemispheric magnetically conjugate geomagnetic coupling and other space-weather-related phenomena. The stations are magnetically conjugate to geomagnetic stations along the west coast of Greenland. The autonomous adaptive low-power instrument platforms being deployed in the Antarctic are designed to operate unattended in remote locations for at least 5 years. They utilize solar power and AGM storage batteries for power, two-way Iridium satellite communication for data acquisition and program/operation modification, support fluxgate and induction magnetometers as well as a dual-frequency GPS receiver and a high-frequency (HF) radio experiment. Size and weight considerations are considered to enable deployment by a small team using small aircraft. Considerable experience has been gained in the development and deployment of remote polar instrumentation that is reflected in the present generation of instrumentation discussed here. We conclude with the lessons learned from our experience in the design, deployment and operation of remote polar instrumentation.

Design and Commissioning of a Transportable Laser Ranging Station STAR-C

NASA Astrophysics Data System (ADS)

Humbert, L.; Hasenohr, T.; Hampf, D.; Riede, W.

An increasing number of space debris and the rise of mega constellations as well as the deployment of small cost efficient satellites are a growing concern for space faring nations and their missions. Hence, a tight network of worldwide stations to support maintenance of catalogues for various tasks such as space surveillance tracking and space traffic management will significantly increase the reliability and availability of the collected data and therefore the safety of missions. A promising concept are transportable laser ranging stations in order to increase the number of observing stations and hence the coverage of the sky. Built and tested on a building test site they can be deployed to a desired site for operation. High energy laser with short pulses provide accurate ranging data to objects in space both cooperative and uncooperative, e.g. objects with a retroreflector and without one. This work introduces the progress of a transportable laser ranging station, of a Surveillance, Tracking and Ranging Container (STAR-C), built into a 20ft ISO container.

H2USA: Siting Refueling Stations in the Northeast

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

Melaina, Marc W; Muratori, Matteo; Zuboy, Jarett

2017-11-01

To achieve cost-effective deployment of both fuel cell electric vehicles (FCEVs) and hydrogen stations, the number of vehicles and public stations must grow together in areas of highest demand. This fact sheet introduces two advanced modeling tools and presents preliminary analysis of the hydrogen refueling station locations needed to support early consumer demand for FCEVs in the Northeast United States. United States.

Nanoracks CUBESAT launcher operations

NASA Image and Video Library

2014-08-20

ISS040-E-103327 (20 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer (upper right) is about to release a pair of NanoRacks CubeSat miniature satellites. The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at center. A blue and white part of Earth and the blackness of space provide the backdrop for the scene.

Nanoracks CUBESAT launcher operations

NASA Image and Video Library

2014-08-19

ISS040-E-103545 (19 Aug. 2014) --- In the grasp of the Japanese robotic arm, the CubeSat deployer (mostly out of frame, upper right) releases a pair of NanoRacks CubeSat miniature satellites (center). The Planet Labs Dove satellites that were carried to the International Space Station aboard the Orbital Sciences Cygnus commercial cargo craft are being deployed between Aug. 19 and Aug. 25. A section of the station solar array wings is at top right. A blue and white part of Earth and the blackness of space provide the backdrop for the scene.

sl2-x7-615

NASA Image and Video Library

2013-09-10

SL2-X7-615 (22 June 1973) --- An overhead view of the Skylab 1 space station cluster in Earth orbit photographed from the Skylab 2 Command/Service Module during the final ?fly around? inspection by the CSM. The space station is sharply contrasted against a black sky background. Note the deployed parasol solar shield which shades the Orbital Workshop where the micrometeoroid shield is missing. The one remaining OWS solar array system wing has been fully deployed successfully. The OWS solar panel on the opposite side is missing completely. Photo credit: NASA

A simple method to reduce discharge of sewage microorganisms from an Antarctic research station.

PubMed

Hughes, Kevin A; Blenkharn, Nigel

2003-03-01

The majority of coastal Antarctic stations release untreated sewage into the near-shore marine environment. This study examined bacterial reproduction within the temporary sewage-holding tanks of Rothera Research Station (Adelaide Island, Antarctic Peninsula) and monitored sewage pollution in the local marine environment. By continuously flushing the sewage-holding tanks with cold seawater we inhibited microbial reproduction and decreased the numbers of bacteria subsequently released into the sea by >90%. The widespread use of this simple method could significantly reduce the numbers of faecal coliform and other non-native microorganisms introduced into the Antarctic marine environment.

Broadband Seismic Array Observation along a ~2000-km-long Linear Profile in South China

NASA Astrophysics Data System (ADS)

Ai, Y.; Zhao, L.; Chen, L.; Zheng, T.; He, Y.; Jiang, M.

2010-12-01

In order to study the interior structure and geodynamic evolution of South China, we have started implementation of a linear seismic array observation in this region since December 2009. The linear array extends for ~2000 km from the northwestern continental interior all the way to the southeastern coastal area, across major tectonic units of South China including the Songpan-Ganze Orogenic Belt (SGOB) in the northwest, the Yangtze Craton (YzC) in the middle, and the Huanan Orogenic Belt (HOB) in the southeast. We plan to deploy a total of 200 broadband stations in the time period from December 2009 to June 2012. All the stations will be equipped with Guralp CMG-3ESP sensors and Ref-tek 130-1 or Ref-tek 72-A digitizers. The entire array observation includes three stages. In the time period from December 2009 to March 2011, 64 stations were deployed with a spatial interval of ~25 km from Chengdu city in Sichuan province in the west to Quanzhou city in Fujian province in the southeast of China. In the second stage, about 70 stations with a spatial interval of ~10 km will be deployed from Gonghe city in Qinghai province in the northwest to Chengdu city in the southeast in the time period from October 2010 to November 2011. In the last stage from April 2011 to June 2012, 66 stations with a spatial interval of ~25 km will be deployed to densify the station coverage along the Chengdu - Quanzhou segment of the profile. We have already analyzed the seismic data collected at the 64 stations using receiver function methods. Our preliminary results show an obvious W-E variation in the crustal thickness of the region. In particular, from inland to offshore of the Fujian Province the crustal thickness decreases, whereas the Poisson's ratio increases. These may indicate decreasing SiO2 and increasing calc-alkaline contents in the crust. The receiver function data also reveal a coherent structure of the 410-km and 660-km discontinuities along the observation profile. ACKNOWLEDGMENTS We acknowledge the financial support of SinoProbe under Grant SinoProbe-02-03

VP Structure of Mount St. Helens, Washington, USA, imaged with local earthquake tomography

USGS Publications Warehouse

Waite, G.P.; Moran, S.C.

2009-01-01

We present a new P-wave velocity model for Mount St. Helens using local earthquake data recorded by the Pacific Northwest Seismograph Stations and Cascades Volcano Observatory since the 18 May 1980 eruption. These data were augmented with records from a dense array of 19 temporary stations deployed during the second half of 2005. Because the distribution of earthquakes in the study area is concentrated beneath the volcano and within two nearly linear trends, we used a graded inversion scheme to compute a coarse-grid model that focused on the regional structure, followed by a fine-grid inversion to improve spatial resolution directly beneath the volcanic edifice. The coarse-grid model results are largely consistent with earlier geophysical studies of the area; we find high-velocity anomalies NW and NE of the edifice that correspond with igneous intrusions and a prominent low-velocity zone NNW of the edifice that corresponds with the linear zone of high seismicity known as the St. Helens Seismic Zone. This low-velocity zone may continue past Mount St. Helens to the south at depths below 5??km. Directly beneath the edifice, the fine-grid model images a low-velocity zone between about 2 and 3.5??km below sea level that may correspond to a shallow magma storage zone. And although the model resolution is poor below about 6??km, we found low velocities that correspond with the aseismic zone between about 5.5 and 8??km that has previously been modeled as the location of a large magma storage volume. ?? 2009 Elsevier B.V.

Broadband seismic effects from train vibrations

NASA Astrophysics Data System (ADS)

Fuchs, Florian; Bokelmann, Götz

2017-04-01

Seismologists rarely study train induced vibrations which are mainly regarded an unwanted source of noise for classical seismological applications such as earthquake monitoring. A few seismological studies try to utilize train vibrations however as active sources, e.g. for subsurface imaging, but they do not focus on the characteristics of the train signal itself. Most available studies on train induced vibrations take an engineering approach and aim at better understanding the generation and short-distance propagation of train induced vibrations, mainly for mitigation and construction purposes. They mostly rely on numerical simulations and/or short-period or accelerometer recordings obtained directly on the train track or up to few hundred meters away and almost no studies exist with seismic recordings further away from the track. In some of these previous studies sharp and equidistant peaks are present in the vibration spectrum of heavy freight trains, but they do not attempt to explain them. Here we show and analyze various train vibration signals obtained from a set of seismic broadband stations installed in the context of the temporary, large-scale regional seismic network AlpArray. The geometrical restrictions of this seismic network combined with budget and safety considerations resulted in a number of broad-band instruments deployed in the vicinity of busy railway lines. On these stations we observe very characteristic seismic signals associated with different types of trains, typically showing pronounced equidistant spectral lines over a wide frequency range. In this study we analyze the nature of such signals and discuss if they are generated by a source effect or by wave propagation effects in near-surface soil layers.

International Space Station (ISS)

NASA Image and Video Library

2007-08-13

As the construction continued on the International Space Station (ISS), STS-118 astronaut and mission specialist Rick Mastracchio participated in the second session of Extra Vehicular Activity (EVA) for the mission. Assisting Mastracchio was Canadian Space Agency representative Dave Williams (out of frame). During the 6 hour, 28 minute space walk, the two removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the Z1 truss. The failed CMG will remain in its temporary stowage location on the exterior of the station until it is returned to Earth on a later Shuttle mission. The new gyroscope is one of four CMGs that are used to control the orbital attitude of the station.

Shuttle-launch triangular space station

NASA Technical Reports Server (NTRS)

Schneider, W. C. (Inventor); Berka, R. B. (Inventor); Kavanaugh, C. (Inventor); Nagy, K. (Inventor); Parish, R. C. (Inventor); Schliesing, J. A. (Inventor); Smith, P. D. (Inventor); Stebbins, F. J. (Inventor); Wesselski, C. J. (Inventor)

1986-01-01

A triangular space station deployable in orbit is described. The framework is comprized of three trusses, formed of a pair of generally planar faces consistine of foldable struts. The struts expand and lock into rigid structural engagement forming a repetition of equilater triangles and nonfolding diagonal struts interconnecting the two faces. The struts are joined together by node fittings. The framework can be packaged into a size and configuration transportable by a space shuttle. When deployed, the framework provides a large work/construction area and ample planar surface area for solar panels and thermal radiators. A plurity of modules are secured to the framework and then joined by tunnels to make an interconnected modular display. Thruster units for the space station orientation and altitude maintenance are provided.

A study of the earth's free core nutation using international deployment of accelerometers gravity data

NASA Technical Reports Server (NTRS)

Cummins, Phil R.; Wahr, John M.

1993-01-01

In this study we consider the influence of the earth's free core nutation (FCN) on diurnal tidal admittance estimates for 11 stations of the globally distributed International Deployment of Accelerometers network. The FCN causes a resonant enhancement of the diurnal admittances which can be used to estimate some properties of the FCN. Estimations of the parameters describing the FCN (period, Q, and resonance strength) are made using data from individual stations and many stations simultaneously. These yield a result for the period of 423-452 sidereal days, which is shorter than theory predicts but is in agreement with many previous studies and suggests that the dynamical ellipticity of the core may be greater than its hydrostatic value.

Small Cube Satellite Deploy

NASA Image and Video Library

2013-11-19

ISS038-E-003870 (19 Nov. 2013) --- Three nanosatellites, known as Cubesats, are deployed from a Small Satellite Orbital Deployer (SSOD) attached to the Kibo laboratory’s robotic arm at 7:10 a.m. (EST) on Nov. 19, 2013. Japan Aerospace Exploration Agency astronaut Koichi Wakata, Expedition 38 flight engineer, monitored the satellite deployment while operating the Japanese robotic arm from inside Kibo. The Cubesats were delivered to the International Space Station Aug. 9, aboard Japan’s fourth H-II Transfer Vehicle, Kounotori-4.

Small Cube Satellite Deploy

NASA Image and Video Library

2013-11-19

ISS038-E-003869 (19 Nov. 2013) --- Three nanosatellites, known as Cubesats, are deployed from a Small Satellite Orbital Deployer (SSOD) attached to the Kibo laboratory’s robotic arm at 7:10 a.m. (EST) on Nov. 19, 2013. Japan Aerospace Exploration Agency astronaut Koichi Wakata, Expedition 38 flight engineer, monitored the satellite deployment while operating the Japanese robotic arm from inside Kibo. The Cubesats were delivered to the International Space Station Aug. 9, aboard Japan’s fourth H-II Transfer Vehicle, Kounotori-4.

Small Cube Satellite Deploy

NASA Image and Video Library

2013-11-19

ISS038-E-003871 (19 Nov. 2013) --- Three nanosatellites, known as Cubesats, are deployed from a Small Satellite Orbital Deployer (SSOD) attached to the Kibo laboratory’s robotic arm at 7:10 a.m. (EST) on Nov. 19, 2013. Japan Aerospace Exploration Agency astronaut Koichi Wakata, Expedition 38 flight engineer, monitored the satellite deployment while operating the Japanese robotic arm from inside Kibo. The Cubesats were delivered to the International Space Station Aug. 9, aboard Japan’s fourth H-II Transfer Vehicle, Kounotori-4.

Small Cube Satellite Deploy

NASA Image and Video Library

2013-11-19

ISS038-E-003872 (19 Nov. 2013) --- Three nanosatellites, known as Cubesats, are deployed from a Small Satellite Orbital Deployer (SSOD) attached to the Kibo laboratory’s robotic arm at 7:10 a.m. (EST) on Nov. 19, 2013. Japan Aerospace Exploration Agency astronaut Koichi Wakata, Expedition 38 flight engineer, monitored the satellite deployment while operating the Japanese robotic arm from inside Kibo. The Cubesats were delivered to the International Space Station Aug. 9, aboard Japan’s fourth H-II Transfer Vehicle, Kounotori-4.

Deployment of Autonomous GPS Stations in Marie Byrd Land, Antartica

NASA Technical Reports Server (NTRS)

Donnellan, A.; Luyendyk, B.; Smith, M.; Dace, G.

1999-01-01

During the 1998-1999 Antarctic field season, we installed three autonomous GPS stations in Marie Byrd Land, West Antarctica to measure glacio-isostatic rebound and rates of spreading across the West Antartic Rift System.

Hazardous Waste Cleanup: Safety-Kleen Corporation in Southampton Township, New Jersey

EPA Pesticide Factsheets

The site has been reportedly in operation since 1976 and is currently an active transfer station for distribution of fresh solvent products and the collection and temporary storage of used solvent wastes (prior to subsequent transportation and recycling

Preliminary Results from the North Anatolian Fault Passive Seismic Experiment: Seismicity and Anisotropy

NASA Astrophysics Data System (ADS)

Biryol, C. B.; Ozacar, A.; Beck, S. L.; Zandt, G.

2006-12-01

The North Anatolian Fault (NAF) is one of the world's largest continental strike-slip faults. Despite much geological work at the surface, the deep structure of the NAF is relatively unknown. The North Anatolian Fault Passive Seismic Experiment is mainly focused on the lithospheric structure of this newly coalescing continental transform plate boundary. In the summer of 2005, we deployed 5 broadband seismic stations near the fault to gain more insight on the background seismicity, and in June 2006 we deployed 34 additional broadband stations along multiple transects crossing the main strand of the NAF and its splays. In the region, local seismicity is not limited to a narrow band near the NAF but distributed widely suggesting widespread continental deformation especially in the southern block. We relocated two of the largest events (M>4) that occurred close to our stations. Both events are 40-50km south of the NAF in the upper crust (6-9 km) along a normal fault with a strike-slip component that previously ruptured during the June 6, 2000 Orta-Cankiri earthquake (M=6.0). Preliminary analysis of SKS splitting for 4 stations deployed in 2005 indicates seismic anisotropy with delay times exceeding 1 sec. The fast polarization directions for these stations are primarily in NE-SW orientation, which remains uniform across the NAF. This direction is at a high angle to the surface trace of the fault and crustal velocity field, suggesting decoupling of lithosphere and mantle flow. Our SKS splitting observations are also similar to that observed from GSN station ANTO in central Turkey and stations across the Anatolian Plateau in eastern Turkey indicating relatively uniform mantle anisotropy throughout the region.

Seismic Structure of Perth Basin (Australia) and surroundings from Passive Seismic Deployments

NASA Astrophysics Data System (ADS)

Issa, N.; Saygin, E.; Lumley, D. E.; Hoskin, T. E.

2016-12-01

We image the subsurface structure of Perth Basin, Western Australia and surroundings by using ambient seismic noise data from 14 seismic stations recently deployed by University of Western Australia (UWA) and other available permanent stations from Geoscience Australia seismic network and the Australian Seismometers in Schools program. Each of these 14 UWA seismic stations comprises a broadband sensor and a high fidelity 3-component 10 Hz geophone, recording in tandem at 250 Hz and 1000 Hz. The other stations used in this study are equipped with short period and broadband sensors. In addition, one shallow borehole station is operated with eight 3 component geophones at depths of between 2 and 44 m. The network is deployed to characterize natural seismicity in the basin and to try and identify any microseismic activity across Darling Fault Zone (DFZ), bounding the basin to the east. The DFZ stretches to approximately 1000 km north-south in Western Australia, and is one of the longest fault zones on the earth with a limited number of detected earthquakes. We use seismic noise cross- and auto-correlation methods to map seismic velocity perturbations across the basin and the transition from DFZ to the basin. Retrieved Green's functions are stable and show clear dispersed waveforms. Travel times of the surface wave Green's functions from noise cross-correlations are inverted with a two-step probabilistic framework to map the absolute shear wave velocities as a function of depth. The single station auto-correlations from the seismic noise yields P wave reflectivity under each station, marking the major discontinuities. Resulting images show the shear velocity perturbations across the region. We also quantify the variation of ambient seismic noise at different depths in the near surface using the geophones in the shallow borehole array.

Validating alternative methodologies to estimate the hydrological regime of temporary streams when flow data are unavailable

NASA Astrophysics Data System (ADS)

Llorens, Pilar; Gallart, Francesc; Latron, Jérôme; Cid, Núria; Rieradevall, Maria; Prat, Narcís

2016-04-01

Aquatic life in temporary streams is strongly conditioned by the temporal variability of the hydrological conditions that control the occurrence and connectivity of diverse mesohabitats. In this context, the software TREHS (Temporary Rivers' Ecological and Hydrological Status) has been developed, in the framework of the LIFE Trivers project, to help managers for adequately implement the Water Framework Directive in this type of water bodies. TREHS, using the methodology described in Gallart et al (2012), defines six temporal 'aquatic states', based on the hydrological conditions representing different mesohabitats, for a given reach at a particular moment. Nevertheless, hydrological data for assessing the regime of temporary streams are often non-existent or scarce. The scarcity of flow data makes frequently impossible the characterization of temporary streams hydrological regimes and, as a consequence, the selection of the correct periods and methods to determine their ecological status. Because of its qualitative nature, the TREHS approach allows the use of alternative methodologies to assess the regime of temporary streams in the lack of observed flow data. However, to adapt the TREHS to this qualitative data both the temporal scheme (from monthly to seasonal) as well as the number of aquatic states (from 6 to 3) have been modified. Two alternatives complementary methodologies were tested within the TREHS framework to assess the regime of temporary streams: interviews and aerial photographs. All the gauging stations (13) belonging to the Catalan Internal Catchments (NE, Spain) with recurrent zero flows periods were selected to validate both methodologies. On one hand, non-structured interviews were carried out to inhabitants of villages and small towns near the gauging stations. Flow permanence metrics for input into TREHS were drawn from the notes taken during the interviews. On the other hand, the historical series of available aerial photographs (typically 10) were examined. In this case, flow permanence metrics were estimated as the proportion of photographs presenting stream flow. Results indicate that for streams being more than 25% of the time dry, interviews systematically underestimated flow, but the qualitative information given by inhabitants was of great interest to understand river dynamics. On the other hand, the use of aerial photographs gave a good estimation of flow permanence, but the seasonality was conditioned to the capture date of the aerial photographs. For these reasons, we recommend to use both methodologies together.

Overview of the Development of the Temporary Sleep Station Hygiene Liner Aboard the International Space Station

NASA Technical Reports Server (NTRS)

Reid, Ethan A.

2010-01-01

Since the beginning of manned operations aboard the International Space Station (ISS), the crew had performed hygiene activities within the aisle way (the habitable volume, not including the sleep areas) of the ISS. The Crew used wet towels, re-hydrated body soap, and "no-rinse" shampoo to cleanse themselves amongst the stowage and systems hardware, referred to as "racks", even without a designated area to dry the wet items. Performing hygiene in this manner became an accepted method; no isolated location was available to the Crew. After several years of hygiene operations, some of the fabric-covered racks began to grow biological material (generically described as mold) and soon became a Crew health concern. Hygiene has one of the strongest impacts on Crew morale, and mandating changes to the Crew routine would have been met with strong resistance. The answer to the conundrum was to develop a liner to be placed within the Temporary Sleep Station (TeSS), one of the Crew s sleeping racks. This liner provided the Crew a means to perform hygiene activities within a private, enclosed area that also significantly decreased the potential to grow mold. This paper will describe the development of the TeSS Hygiene Liner, its impacts on the ISS and Crew, as well as its contribution to hygiene activities used in space today.

Developing a novel approach to analyse the regimes of temporary streams and their controls on aquatic biota

NASA Astrophysics Data System (ADS)

Gallart, F.; Prat, N.; García-Roger, E. M.; Latron, J.; Rieradevall, M.; Llorens, P.; Barberá, G. G.; Brito, D.; de Girolamo, A. M.; Lo Porto, A.; Neves, R.; Nikolaidis, N. P.; Perrin, J. L.; Querner, E. P.; Quiñonero, J. M.; Tournoud, M. G.; Tzoraki, O.; Froebrich, J.

2011-10-01

Temporary streams are those water courses that undergo the recurrent cessation of flow or the complete drying of their channel. The biological communities in temporary stream reaches are strongly dependent on the temporal changes of the aquatic habitats determined by the hydrological conditions. The use of the aquatic fauna structural and functional characteristics to assess the ecological quality of a temporary stream reach can not therefore be made without taking into account the controls imposed by the hydrological regime. This paper develops some methods for analysing temporary streams' aquatic regimes, based on the definition of six aquatic states that summarize the sets of mesohabitats occurring on a given reach at a particular moment, depending on the hydrological conditions: flood, riffles, connected, pools, dry and arid. We used the water discharge records from gauging stations or simulations using rainfall-runoff models to infer the temporal patterns of occurrence of these states using the developed aquatic states frequency graph. The visual analysis of this graph is complemented by the development of two metrics based on the permanence of flow and the seasonal predictability of zero flow periods. Finally, a classification of the aquatic regimes of temporary streams in terms of their influence over the development of aquatic life is put forward, defining Permanent, Temporary-pools, Temporary-dry and Episodic regime types. All these methods were tested with data from eight temporary streams around the Mediterranean from MIRAGE project and its application was a precondition to assess the ecological quality of these streams using the current methods prescribed in the European Water Framework Directive for macroinvertebrate communities.

The Seismic Broad Band Western Mediterranean (wm) Network and the Obs Fomar Pool: Current state and Obs activities.

NASA Astrophysics Data System (ADS)

Pazos, Antonio; Davila, Jose Martin; Buforn, Elisa; Bezzeghoud, Mourad; Harnafi, Mimoun; Mattesini, Mauricio; Caldeira, Bento; Hanka, Winfried; El Moudnib, Lahcen; Strollo, Angelo; Roca, Antoni; Lopez de Mesa, Mireya; Dahm, Torsten; Cabieces, Roberto

2016-04-01

The Western Mediterranean (WM) seismic network started in 1996 as an initiative of the Royal Spanish Navy Observatory (ROA) and the Universidad Complutense de Madrid (UCM), with the collaboration of the GeoForschungsZentrum (GFZ) of Potsdam. A first broad band seismic station (SFUC) was installed close to Cádiz (South Spain). Since then, additional stations have been installed in the Ibero-Moghrebian region. In 2005, the "WM" code was assigned by the FDSN and new partners were jointed: Evora University (UEVO, Portugal), the Scientifique Institute of Rabat (ISRABAT, Morocco), and GFZ. Now days, the WM network is composed by 15 BB stations, all of them with Streckaisen STS-2 or STS-2.5 sensors, Quanterra or Earthdata digitizers and SeiscomP. Most them have co-installed a permanent geodetic GPS stations, and some them also have an accelerometer. There are 10 stations deployed in Spanish territory (5 in the Iberian peninsula, 1 in Balearic islands and 4 in North Africa Spanish places) with VSAT or Internet communications, 2 in Portugal (one of them without real time), and 3 in Morocco (2 VSAT and 1 ADSL). Additionally, 2 more stations (one in South Spain and one in Morocco) will be installed along this year. Additionally ROA has deployed a permanent real time VBB (CMG-3T: 360s) station at the Alboran Island. Due to the fact that part of the seismic activity is located at marine areas, and also because of the poor geographic azimuthal coverage at some zones provided by the land stations (specially in the SW of the San Vicente Cape area), ROA and UCM have acquired six broad band "LOBSTERN" OBS, manufactured by KUM (Kiel, Germany), conforming the OBS FOMAR pool. Three of them with CMG-40T sensor and the other with Trillium 120. These OBS were deployed along the Gibraltar strait since January to November 2014 to study the microseismicity in the Gibraltar strait area. In September 2015 FOMAR network has been deployed in SW of the San Vicente Cape for 8 months as a part of ALERTES-RIM project. In this work the current state and future plans of the WM network, the results of the Gibraltar strait campaign and San Vicente Cape OBS experiment are shown.

Multidisciplinary Observations of Subduction (MOOS) Experiment in South-Central Alaska

NASA Astrophysics Data System (ADS)

Christensen, D.; Abers, G.; Freymueller, J.

2008-12-01

Seismic and geodetic data are being collected in the Kenai Peninsula and surrounding area of south central Alaska as part of the PASSCAL experiment MOOS. A total of 34 broadband seismic stations were deployed between the summers of 2007 and 2008. Seventeen of these stations continue to operate for an additional year and are scheduled to be removed in the summer of 2009. Numerous GPS campaign sites have and will be visited during the same time period. The MOOS seismic deployment provides coverage across the interplate coupled zone and adjacent transition zone in the shallow parts of the Alaskan subduction zone. It is a southern extension of an earlier broadband deployment BEAAR (Broadband Experiment Across the Alaska Range) to the north. When integrated with the previous BEAAR experiment, these data will allow high-resolution broadband imaging along a 600 km long transect over the Alaska subduction zone, at 10-15 km station spacing. The MOOS deployment allows us to test several hypotheses relating to the postulated subduction of the Yakutat Block and the nature of the coupled zone which ruptured in the great 1964 earthquake. The seismic and geodetic stations cover an area that includes part of the 1964 main asperity and the adjacent, less coupled, region to the southwest. Data gathered from this experiment will shed light on the nature of this boundary from both a geodetic and seismic (or earth structure) perspective. Shallow seismicity recorded by this network greatly improves the catalog of events in this area and helps to delineate active features in the subduction complex. Preliminary results from this project will be presented.

A Dramatic Increase in Seismic Observations in the Central and Eastern US

NASA Astrophysics Data System (ADS)

Woodward, R.; Busby, R.; Simpson, D.; Alvarez, M.; Vernon, F.

2009-05-01

The USArray Transportable Array (TA) is a network of 400 seismograph stations that is systematically moving west-to-east across the contiguous United States. The TA is part of the National Science Foundation's multi- disciplinary EarthScope program. The TA has already occupied over 700 stations in the western US, and is continuing its multi-year migration towards the Atlantic coast before heading for Alaska. The stations use a grid-like deployment with 70 km separation between stations. At any given time there are approximately 400 stations operational, occupying a nominal 800 km by 2000 km "footprint." Each station is operated for two years. TA stations consist of three component broadband seismometers, with a few sites in the westernmost United States also including three component strong motion instruments. The instruments are installed about two meters below the surface, in thermally stable vaults. All stations transmit continuous data in near-real-time, and the data are freely distributed through the IRIS Data Management Center. TA stations can be upgraded to incorporate high frequency or strong motion instrument. Organizations can also "adopt" stations after installation by reimbursing the cost of the hardware, so that the stations become permanent. The TA is presently operating in the swath of the country extending from Texas to Montana. From 2010 to 2013 the TA will occupy ~800 sites in the central and eastern US. The array will be centered on the New Madrid, MO region during the bicentennial of the 1811-1812 earthquakes. During the TA deployment every existing or planned nuclear plant in the eastern US will be within 70 km of at least four new seismic stations. Thus, this station deployment in the eastern half of the US presents an unprecedented opportunity for improving source characterization, modeling the regional velocity and attenuation structure, and mapping seismic zones down to low magnitude thresholds. We will provide an overview of TA installation plans, instrumentation, and data so that scientists and decision makers are better prepared to capitalize on the unique opportunity presented by the TA moving through the central and eastern US. We will provide examples of TA station performance, as well as examples of data quality and seismic detection thresholds observed in the western US.

The universal scissor component: Optimization of a reconfigurable component for deployable scissor structures

NASA Astrophysics Data System (ADS)

Alegria Mira, Lara; Thrall, Ashley P.; De Temmerman, Niels

2016-02-01

Deployable scissor structures are well equipped for temporary and mobile applications since they are able to change their form and functionality. They are structural mechanisms that transform from a compact state to an expanded, fully deployed configuration. A barrier to the current design and reuse of scissor structures, however, is that they are traditionally designed for a single purpose. Alternatively, a universal scissor component (USC)-a generalized element which can achieve all traditional scissor types-introduces an opportunity for reuse in which the same component can be utilized for different configurations and spans. In this article, the USC is optimized for structural performance. First, an optimized length for the USC is determined based on a trade-off between component weight and structural performance (measured by deflections). Then, topology optimization, using the simulated annealing algorithm, is implemented to determine a minimum weight layout of beams within a single USC component.

2011 Army Strategic Planning Guidance

DTIC Science & Technology

2011-03-25

TESI ) of 22,000 Soldiers, the Army’s total force by the end of the mid-term period is programmed to be 520K (AC). We will achieve a more...dwell ratios, extending TESI authority to adequately man deploying units and sustain the All-Volunteer Force, right-sizing the generating force, and... TESI Temporary End-Strength Increase WMD Weapons of Mass Destruction 2011 ARMY STRATEGIC PLANNING GUIDANCE Page 19 2011

Study of selected tether applications in space, phase 3, volume 2

NASA Technical Reports Server (NTRS)

1986-01-01

The results of a Phase 3 study of two Selected Tether Applications in Space (STAIS); deorbit of a Shuttle and launch of an Orbital Transfer Vehicle (OTV), both from the space station using a tether were examined. The study objectives were to: perform a preliminary engineering design, define operational scenarios, develop a common cost model, perform cost benefits analyses, and develop a Work Breakdown Structure (WBS). Key features of the performance analysis were to identify the net increases in effective Shuttle cargo capability if tethers are used to assist in the deorbit of Shuttles and the launching of the OTVs from the space station and to define deployer system designs required to accomplish these tasks. Deployer concepts were designed and discussed. Operational scenarios, including timelines, for both tethered and nontethered Shuttle and OTV operations at the space station were evaluated. A summary discussion of the Selected Tether Applications Cost Model (STACOM) and the results of the cost benefits analysis are presented. Several critical technologies needed to implement tether assisted deployment of payloads are also discussed. Conclusions and recommendations are presented.

Magnetotelluric Investigation of Melt Storage Beneath Okmok Caldera, Alaska

NASA Astrophysics Data System (ADS)

Bennington, N. L.; Bedrosian, P.; Key, K.; Zelenak, G.

2015-12-01

Alaska accounts for nearly 99% of the seismic moment release within the US. Much of this is associated with the Aleutian volcanic arc, the most tectonically active region in North America, and an ideal location for studying arc magmatism. Okmok is an active volcano located in the central Aleutian arc, defined by a pair of nested, 10 km diameter calderas. The subdued topography of Okmok, relative to other Aleutian volcanoes, improves access and permits dense sampling within the caldera closer to the underlying magmatic system. Okmok volcano was selected as the site of study for this project due to frequent volcanic activity and the presence of a crustal magma reservoir as inferred from previous coarse resolution seismic studies. In June-July 2015, we carried out an amphibious geophysical field deployment at Okmok. Onshore work in and around the volcano included collection of an array of magnetotelluric (MT) stations and installation of a temporary, year-long seismic array. A ring of 3D offshore MT deployments made around the island augments the onshore array. An additional 2D tectonic-scale profile spans the trench, volcanic arc, and backarc. This new geophysical data will be used to gain a greater understanding of Aleutian arc melt generation, migration, and storage beneath an active caldera. We present results from the analysis of the newly collected amphibious 3D MT data. This data will be used to model the distribution and migration of melt within Okmok's crustal magma reservoir. Initial processing of the data shows strong MT signal levels, in particular from a geomagnetic storm that occurred from June 21-23, 2015. A companion abstract discussing the 2D tectonic scale MT profile, which constrains the mantle and deep crust beneath Okmok volcano, is discussed by Zelenak et al.

Experimental Infrasound Studies in Nevada

NASA Astrophysics Data System (ADS)

Herrin, E. T.; Negraru, P. T.; Golden, P.; Williams, A.

2009-12-01

An experimental propagation study was carried out in Nevada in June 2009 on Julian days 173-177. During this field experiment we deployed 16 single channel digital infrasound recorders to monitor the munitions disposal activities near Hawthorne, NV. The sensors were deployed in a single line and placed approximately 12 km apart at distances ranging from 2 to 177 km. A four element semi-permanent infrasound array named FNIAR was installed approximately 154 km north of the detonation site in line with the individual temporary recorders. Tropospheric arrivals were observed during all days of the experiment, but during day 176 the observed arrivals had very large amplitudes. A large signal was observed at 58 km from the detonation site with amplitude as large as 4 Pascals, while at 94 km no signal was observed. At FNIAR the amplitude of the tropospheric arrival was 1 Pascal. During this day meteorological data acquired in the propagation path showed a strong jet stream to the north. On day 177 we were not able to identify tropospheric arrivals beyond 34 km, but at stations beyond 152 km we observed stratospheric arrivals. Continuous monitoring of these signals at FNIAR shows that stratospheric arrivals are the most numerous. In a two month period, from 06/15/2009 to 08/15/2009 there were 35 operational days at the Hawthorne disposal facility resulting in 212 explosions with known origin times. Based on the celerity values there were 115 explosions that have only stratospheric arrivals (celerities of 300-275 m/s), 72 explosions with both tropospheric (celerities above 330 m/s) and stratospheric arrivals, 20 explosions that were not detected and five explosions that have only tropospheric arrivals.

On the Viability of Using Autonomous Three-Component Nodal Geophones to Calculate Teleseismic Ps Receiver Functions with an Application to the Old Faithful Hydrothermal System and the Cascadia Subduction Zone

NASA Astrophysics Data System (ADS)

Ward, K. M.; Lin, F. C.

2017-12-01

Recent advances in seismic data-acquisition technology paired with an increasing interest from the academic passive source seismological community have opened up new scientific targets and imaging possibilities, often referred to as Large-N experiments (large number of instruments). The success of these and other deployments has motivated individual researchers, as well as the larger seismological community, to invest in the next generation of nodal geophones. Although the new instruments have battery life and bandwidth limitations compared to broadband instruments, the relatively low deployment and procurement cost of these new nodal geophones provides an additional novel tool for researchers. Here, we explore the viability of using autonomous three-component nodal geophones to calculate teleseismic Ps receiver functions by comparison of co-located broadband stations and highlight some potential advantages with a dense nodal array deployed around the Upper Geyser basin in Yellowstone National Park. Two key findings from this example include (1) very dense nodal arrays can be used to image small-scale features in the shallow crust that typical broadband station spacing would alias, and (2) nodal arrays with a larger footprint could be used to image deeper features with greater or equal detail as typical broadband deployments but at a reduced deployment cost. The success of the previous example has motivated a larger 2-D line across the Cascadia subduction zone. In the summer of 2017, we deployed 174 nodal geophones with an average site spacing of 750 m. Synthetic tests with dense station spacing ( 1 km) reveal subtler features of the system that is consistent with our preliminary receiver function results from our Cascadia deployment. With the increasing availability of nodal geophones to individual researchers and the successful demonstration that nodal geophones are a viable instrument for receiver function studies, numerous scientific targets can be investigated at reduced costs or in expanded detail.

Tethered Satellite System (TSS-1R)-Post Flight (STS-75) Engineering Performance Report

NASA Technical Reports Server (NTRS)

Lavoie, Anthony R.

1996-01-01

The first mission of the Tethered Satellite deployer was flown onboard Atlantis in 1992 during the Space Transportation System (STS) flight STS-46. Due to a mechanical interference with the level wind mechanism the satellite was only Deployed to 256 m rather than the planned 20,000 m. Other problems were also experienced during the STS-46 flight and several modifications were made to the Deployer and Satellite. STS-75 was a reflight of the Tethered Satellite System 1 (TSS-1) designated as Tethered Satellite System 1 Reflight (TSS-1 R) onboard Columbia. As on STS-46, the TSS payload consisted of the Deployer, the Satellite, 3 cargo bay mounted experiments: Shuttle Electrodynamic Tether System (SETS), Shuttle Potential and Return Electron Experiment (SPREE), Deployer Core Equipment (DCORE) 4 Satellite mounted experiments: Research on Electrodynamics Tether Effects (RETE), Research on Orbital Plasma Electrodynamics (ROPE), Satellite Core Instruments (SCORE), Tether Magnetic Field Experiment (TEMAG) and an aft flight deck camera: Tether Optical Phenomena Experiment (TOP). Following successful pre-launch, launch and pre-deployment orbital operations, the Deployer deployed the Tethered Satellite to 19,695 m at which point the tether broke within the Satellite Deployment Boom (SDB). The planned length for On-Station I (OST1) was 20,700 m The Satellite flew away from the Orbiter with the tether attached. The satellite was "safed" and placed in a limited power mode via the RF link. The Satellite was contacted periodically during overflights of ground stations. Cargo bay science activities continued for the period of time allocated to TSS-1 R operations.

Observations and modeling of seismic background noise

USGS Publications Warehouse

Peterson, Jon R.

1993-01-01

The preparation of this report had two purposes. One was to present a catalog of seismic background noise spectra obtained from a worldwide network of seismograph stations. The other purpose was to refine and document models of seismic background noise that have been in use for several years. The second objective was, in fact, the principal reason that this study was initiated and influenced the procedures used in collecting and processing the data.With a single exception, all of the data used in this study were extracted from the digital data archive at the U.S. Geological Survey's Albuquerque Seismological Laboratory (ASL). This archive dates from 1972 when ASL first began deploying digital seismograph systems and collecting and distributing digital data under the sponsorship of the Defense Advanced Research Projects Agency (DARPA). There have been many changes and additions to the global seismograph networks during the past twenty years, but perhaps none as significant as the current deployment of very broadband seismographs by the U.S. Geological Survey (USGS) and the University of California San Diego (UCSD) under the scientific direction of the IRIS consortium. The new data acquisition systems have extended the bandwidth and resolution of seismic recording, and they utilize high-density recording media that permit the continuous recording of broadband data. The data improvements and continuous recording greatly benefit and simplify surveys of seismic background noise.Although there are many other sources of digital data, the ASL archive data were used almost exclusively because of accessibility and because the data systems and their calibration are well documented for the most part. Fortunately, the ASL archive contains high-quality data from other stations in addition to those deployed by the USGS. Included are data from UCSD IRIS/IDA stations, the Regional Seismic Test Network (RSTN) deployed by Sandia National Laboratories (SNL), and the TERRAscope network deployed by the California Institute of Technology in cooperation with other institutions.A map showing the approximate locations of the stations used in this study is provided in Figure 1. One might hope for a better distribution of stations in the southern hemisphere, especially Africa and South America, in order to look for regional variations in seismic noise (apart from the major differences between continental, coastal and island sites). Unfortunately, anyone looking for subtle regional variations in seismic noise is probably going to be disappointed by the spectral data presented in this report because much of the station data appear to be dominated by local disturbances caused by instrumental, environmental, cultural, or surf noise. Better instruments and better instrument siting, or a well-funded field program, will be needed before a global isoseismal noise map can be produced. However, by assembling a composite of background noise from a large network of stations, many of the local station variables are masked, and it is possible to create generalized spectral plots of Earth noise for hypothetical quiet and noisy station sites.

Thermoelectric generator installation at Divide Road Weather Information Systems (RWIS).

DOT National Transportation Integrated Search

2016-04-13

The Department of Transportation and Public Facilities (DOT&PF) has a network of Road Weather Information System (RWIS) environmental sensor stations (ESS) deployed along the road network. Six of the stations do not have access to commercial power an...

Deployment of sustainable fueling/charging systems at California highway safety roadside rest areas.

DOT National Transportation Integrated Search

2016-12-01

The transportation and electricity sectors are facing the challenges of shifting toward a sustainable future. Building hydrogen : fueling stations for fuel cell vehicles and fast charging stations for electric vehicles (EV), and installing grid-level...

Understanding the Effect of Stratification on Vertical and Temporal Heterogenieties of Cyanobacteria Blooms in Lakes Using a Long Term in-situ Monitoring Station

NASA Astrophysics Data System (ADS)

Wilkinson, A.; Guala, M.; Hondzo, M.

2017-12-01

Harmful Algal Blooms (HAB) are made up of potentially toxic freshwater microorganisms called cyanobacteria, because of this they are a ecological and public health hazard. The occurrences of toxic HAB are unpredictable and highly spatially and temporary variable in freshwater ecosystems. To study the abiotic drivers for toxic HAB, a floating research station has been deployed in a hyper-eutrophic lake in Madison Lake, Minnesota, from June-October 2016. This research station provides full depth water quality (hourly) and meteorological monitoring (5 minutes). Water quality monitoring is performed by an autonomously traversed water quality sonde that provides chemical, physical and biological measurements; including phycocyanin, a photosynthetic pigment distinct to cyanobacteria. A bloom of cyanobacteria recorded in the epiliminion in mid-July was driven by prolonged strong thermal stratification in the water column, high surface water temperatures and high phosphate concentrations in the epiliminion. The high biovolume (BV) persisted until late September and was sustained below the surface after stratification weakened, when the thermocline did not confine cyanobacteria-rich layers any more, and cyanobacteria vertical heterogeneities decayed in the water column. High correlations among BV stratification, surface water temperature, and stratification stability informed the development of a quantitative relationship to determine how BV heterogeneities vary with thermal structure in the water column. The BV heterogeneity decreased with thermal stratification stability and surface water temperature, and the dynamic lake stability described by the Lake Number. Finally the location of maximum BV accumulation showed diurnal patterns ie. BV peaks were observed at 1 m depth during the day and deeper layers during the night, which followed patterns in light penetration and thermocline depth. These findings capture cyanobacteria vertical and temporal heterogeneities on a on full depth, seasonal scale and quantify BV distribution throughout the water column under different stratification conditions, which can be important for mitigating risks of contamination of drinking water and recreational exposure.

Observations of Near-Field Rotational Motions from Oklahoma Seismicity using Applied Technology Associate Sensors

NASA Astrophysics Data System (ADS)

Ringler, A. T.; Anthony, R. E.; Holland, A. A.; Wilson, D. C.

2017-12-01

Characterizing rotational motions from moderate-sized earthquakes in the near-field has the potential to improve earthquake engineering and seismic gradiometry by better characterizing the rotational component of the seismic wavefield, but has remained challenging due to the limited development of portable, low-noise rotational sensors. Here, we test Applied Technology Associate (ATA) Proto-Seismic Magnetohydrodynamic (SMHD) three-component rotational rate sensors at Albuquerque Seismological Laboratory (ASL) for self-noise and sensitivity before deploying them at U.S. Geological Survey (USGS) temporary aftershock station OK38 in Waynoka, Oklahoma. The sensors have low self-noise levels below 2 Hz, making them ideal to record local rotations. From April 11, 2017 to June 6, 2017 we recorded the translational and rotational motions of over 155 earthquakes of ML≥2.0 within 2 degrees of the station. Using the recorded events we compare Peak Ground Velocity (PGV) with Peak Ground Rotation Rate (PG). For example, we measured a maximal PG of 0.00211 radians/s and 0.00186 radians/s for the horizontal components of the two rotational sensors during the Mwr=4.2 event on May 13, 2017 which was 0.5 km from that station. Similarly, our PG for the vertical rotational components were 0.00112 radians/s and 0.00085 radians/s. We also measured Peak Ground Rotations (PGω) as a function of seismic moment, as well as mean vertical Power Spectral Density (PSD) with mean horizontal PSD power levels. We compute apparent phase velocity directly from the rotational data, which may have may improve estimates of local site effects. Finally, by comparing various rotational and translational components we look at potential implications for estimating local event source parameters, which may help in identifying phenomena such as repeating earthquakes by using differences in the rotational components correlation.

Lithospheric Structure of Arabia from the Joint Inversion of P- and S-wave Receiver Functions and Dispersion Velocities

NASA Astrophysics Data System (ADS)

Julia, Jordi; Al-Amri, Abdullah; Pasyanos, Michael; Rodgers, Arthur; Matzel, Eric; Nyblade, Andrew

2013-04-01

Seismic imaging of the lithosphere under the Arabian shield and platform is critical to help answer important geologic questions of regional and global interest. The Arabian Shield can be regarded as an amalgamation of several arcs and microplates of Proterozoic age that culminated in the accretion of the Arabian portion of Gondwana during the Pan-African event at ~550 Ma and the role of important geologic features observed on the surface - such as the lineaments and shear zones separating the Proterozoic terrains in the shield - is not completely understood. Also, current models of Precambrian crustal evolution predict that Proterozoic terranes are underlain by fertile (FeO-rich) cratonic roots that should promote the production of mafic magmas and underplating of the Arabian shield terranes, and the shield contains Tertiary and Quaternary volcanic rocks related to the early stages of the Red Sea formation that might also be related to plume-related lithospheric "erosion". In order to better understand these relationships, we are developing new velocity models of litospheric structure for the Arabian shield and platform from the joint inversion of up to four seismic data sets: P-wave receiver functions, S-wave receiver functions, dispersion velocities from surface-waves, and dispersion velocities from ambient-noise cross-correlations. The joint inversion combines constraints on crustal thickness from P-wave receiver functions, constraints on lithospheric thickness from S-wave receiver functions and constraints on S-velocity and S-velocity gradients from dispersion velocities to produce detailed S-velocity profiles under single recording stations. We will present S-velocity profiles for a number of permanent stations operated by the Saudi Geological Survey and the King ing Abdulaziz Center for Science and Technology as well as stations from past temporary deployments and discuss the implications of the velocity models regarding composition and tectonics of the Arabian shield and platform.

Crustal anisotropy from Moho converted Ps wave splitting and geodynamic implications in Northeastern margin of Tibetan Plateau

NASA Astrophysics Data System (ADS)

Xie, Z.; Wu, Q.; Zhang, R.

2017-12-01

Collision between Indian and Eurasian result in intense deformation and crustal shortening in the Tibetan Plateau. NE margin of Tibetan Plateau experienced complex deformation between Qilian orogen and its adjacent blocks, Alxa Block in the north and Ordos Block in the east. We focus on if there any evidences exist in the NE margin of Tibetan Plateau, which can support crustal channel flow model. China Earthquake Administration had deployed temporary seismic array which is called ChinaArray Phase Ⅱ, dense seismic stations covered NE margin of Tibetan Plateau. Seismic data recorded by 81 seismic stations is applied in this research. We calculated receiver functions with time-domain deconvolution. We selected RFs which have clear Ps phase both in radial and transverse components to measure Ps splitting owing to crustal anisotropy, and 130 pairs of anisotropy parameters of 51 seismic stations were obtained. We would like to discuss about dynamic mechanism of this area using crustal anisotropy associated with the result of SKS-splitting and surface constrains like GPS velocity. The result can be summarized as follows. The large scale of delay time imply that the crustal anisotropy mainly derives from middle to lower crust rather than upper crust. In the southeastern part of the research area, crustal anisotropy is well agree with the result computed form SKS-splitting and GPS velocity directions trending NWW-SEE or E-W direction. This result imply a vertically coherent deformation in the area as the directions of crustal anisotropy trend to be perpendicular to the direction of normal stress. In the middle and north part of the research area, the fast polarization direction of crustal anisotropy is NEE-SWW or E-W direction, parallels with direction of GPS velocity, but differ to the direction of the result of SKS-splitting. This result may imply that decoupled deformation in this area associated with middle to lower crustal flow.

Seismic Structure of the Antarctic Upper Mantle and Transition Zone Unearthed by Full Waveform Adjoint Tomography

NASA Astrophysics Data System (ADS)

Lloyd, A. J.; Wiens, D.; Zhu, H.; Tromp, J.; Nyblade, A.; Anandakrishnan, S.; Aster, R. C.; Huerta, A. D.; Winberry, J. P.; Wilson, T. J.; Dalziel, I. W. D.; Hansen, S. E.; Shore, P.

2017-12-01

The upper mantle and transition zone beneath Antarctica and the surrounding ocean are among the poorest seismically imaged regions of the Earth's interior. Over the last 1.5 decades researchers have deployed several large temporary broadband seismic arrays focusing on major tectonic features in the Antarctic. The broader international community has also facilitated further instrumentation of the continent, often operating stations in additional regions. As of 2016, waveforms are available from almost 300 unique station locations. Using these stations along with 26 southern mid-latitude seismic stations we have imaged the seismic structure of the upper mantle and transition zone using full waveform adjoint techniques. The full waveform adjoint inversion assimilates phase observations from 3-component seismograms containing P, S, Rayleigh, and Love waves, including reflections and overtones, from 270 earthquakes (5.5 ≤ Mw ≤ 7.0) that occurred between 2001-2003 and 2007-2016. We present the major results of the full waveform adjoint inversion following 20 iterations, resulting in a continental-scale seismic model (ANT_20) with regional-scale resolution. Within East Antarctica, ANT_20 reveals internal seismic heterogeneity and differences in lithospheric thickness. For example, fast seismic velocities extending to 200-300 km depth are imaged beneath both Wilkes Land and the Gamburtsev Subglacial Mountains, whereas fast velocities only extend to 100-200 km depth beneath the Lambert Graben and Enderby Land. Furthermore, fast velocities are not found beneath portions of Dronning Maud Land, suggesting old cratonic lithosphere may be absent. Beneath West Antarctica slow upper mantle seismic velocities are imaged extending from the Balleny Island southward along the Transantarctic Mountains front, and broaden beneath the southern and northern portion of the mountain range. In addition, slow upper mantle velocities are imaged beneath the West Antarctic coast extending from Marie Byrd Land to the Antarctic Peninsula. This region of slow velocity only extends to 150-200 km depth beneath the Antarctic Peninsula, while elsewhere it extends to deeper upper mantle depths and possibly into the transition zone as well as offshore, suggesting two different geodynamic processes are at play.

View of MS Mastracchio participating in EVA 2 during STS-118/Expedition 15 Joint Operations

NASA Image and Video Library

2007-08-13

S118-E-06969 (13 Aug. 2007) --- Astronaut Rick Mastracchio, STS-118 mission specialist, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk, Mastracchio and astronaut Dave Williams (out of frame), mission specialist representing the Canadian Space Agency, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

View of MS Williams installing the new CMG during Expedition 15/STS-118 EVA 2

NASA Image and Video Library

2007-08-13

ISS015-E-22358 (13 Aug. 2007) --- Astronaut Dave Williams, STS-118 mission specialist representing the Canadian Space Agency, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk Williams and astronaut Rick Mastracchio (out of frame), mission specialist, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

View of MS Mastracchio participating in EVA 2 during STS-118/Expedition 15 Joint Operations

NASA Image and Video Library

2007-08-13

S118-E-06968 (13 Aug. 2007) --- Astronaut Rick Mastracchio, STS-118 mission specialist, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk, Mastracchio and astronaut Dave Williams (out of frame), mission specialist representing the Canadian Space Agency, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

View of MS Williams installing the new CMG during Expedition 15/STS-118 EVA 2

NASA Image and Video Library

2007-08-13

ISS015-E-22371 (13 Aug. 2007) --- Astronaut Dave Williams, STS-118 mission specialist representing the Canadian Space Agency, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk, Williams and astronaut Rick Mastracchio (out of frame), mission specialist, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

View of MS Williams installing the new CMG during Expedition 15/STS-118 EVA 2

NASA Image and Video Library

2007-08-13

ISS015-E-22355 (13 Aug. 2007) --- Astronaut Dave Williams, STS-118 mission specialist representing the Canadian Space Agency, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk Williams and astronaut Rick Mastracchio (out of frame), mission specialist, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

View of MS Williams installing the new CMG during Expedition 15/STS-118 EVA 2

NASA Image and Video Library

2007-08-13

ISS015-E-22364 (13 Aug. 2007) --- Astronaut Dave Williams, STS-118 mission specialist representing the Canadian Space Agency, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk, Williams and astronaut Rick Mastracchio (out of frame), mission specialist, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

View of MS Mastracchio as he makes his way to the ESP2 during EVA 2

NASA Image and Video Library

2007-08-13

S118-E-07019 (13 Aug. 2007) --- Astronaut Rick Mastracchio, STS-118 mission specialist, participates in the mission's second planned session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the 6-hour, 28-minute spacewalk, Mastracchio and astronaut Dave Williams (out of frame), mission specialist representing the Canadian Space Agency, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior until it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

International Space Station (ISS)

NASA Image and Video Library

2007-08-13

As the construction continued on the International Space Station (ISS), STS-118 astronaut and mission specialist, Dave Williams, representing the Canadian Space Agency, was anchored on the foot restraint of the Canadarm2 as he participated in the second session of Extra Vehicular Activity (EVA) for the mission. Assisting Williams was Rick Mastracchio (out of frame). During the 6 hour, 28 minute space walk, the two removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the Z1 truss. The failed CMG will remain in its temporary stowage location on the exterior of the station until it is returned to Earth on a later Shuttle mission. The new gyroscope is one of four CMGs that are used to control the orbital attitude of the station.

SSOD on JEM RMS

NASA Image and Video Library

2012-10-04

ISS033-E-009269 (4 Oct. 2012) --- A Small Satellite Orbital Deployer (SSOD) attached to the Japanese module’s robotic arm is featured in this image photographed by an Expedition 33 crew member on the International Space Station. Several tiny satellites were released outside the Kibo laboratory using the SSOD on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment.

Next Generation Polar Seismic Instrumentation Challenges

NASA Astrophysics Data System (ADS)

Parker, T.; Beaudoin, B. C.; Gridley, J.; Anderson, K. R.

2011-12-01

Polar region logistics are the limiting factor for deploying deep field seismic arrays. The IRIS PASSCAL Instrument Center, in collaboration with UNAVCO, designed and deployed several systems that address some of the logistical constraints of polar deployments. However, continued logistics' pressures coupled with increasingly ambitious science projects require further reducing the logistics required for deploying both summer and over winter stations. Our focus is to reduce station power requirements and bulk, thereby minimizing the time and effort required to deploy these arrays. We will reduce the weight of the battery bank by incorporating the most applicable new high energy-density battery technology. Using these batteries will require a completely new power management system along with an appropriate smart enclosure. The other aspect will be to integrate the digitizing system with the sensor. Both of these technologies should reduce the install time and shipping volume plus weight while reducing some instrument costs. We will also continue work on an effective Iridium telemetry solution for automated data return. The costs and limitations of polar deep-field science easily justifies a specialized development effort but pays off doubly in that we will continue to leverage the advancements in reduced logistics and increased performance for the benefit of low-latitude seismic research.

KSC-98pc1661

NASA Image and Video Library

1998-11-06

Still suspended by a crane and cables in the Space Station Processing Facility, yet hidden by the top of the Z1 integrated truss structure, the Passive Common Berthing Mechanism (PCBM) is lowered onto the truss for attachment. Workers at the top of a workstand guide it into place. A component of the International Space Station (ISS), the Z1 truss will be used for the temporary installation of the P6 truss segment to the Unity connecting module. The P6 truss segment contains the solar arrays and batteries which will provide early station power. The truss is scheduled to be launched aboard STS-92 in late 1999

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51263 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51264 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51265 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm (out of frame) grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth.

The NSF Earthscope USArray Instrumentation Network

NASA Astrophysics Data System (ADS)

Davis, G. A.; Vernon, F.

2012-12-01

Since 2004, the Transportable Array component of the USArray Instrumentation Network has collected high resolution seismic data in near real-time from over 400 geographically distributed seismic stations. The deployed footprint of the array has steadily migrated across the continental United States, starting on the west coast and gradually moving eastward. As the network footprint shifts, stations from various regional seismic networks have been incorporated into the dataset. In 2009, an infrasound and barometric sensor component was added to existing core stations and to all new deployments. The ongoing success of the project can be attributed to a number of factors, including reliable communications to each site, on-site data buffering, largely homogenous data logging hardware, and a common phase-locked time reference between all stations. Continuous data quality is ensured by thorough human and automated review of data from the primary sensors and over 24 state-of-health parameters from each station. The staff at the Array Network Facility have developed a number of tools to visualize data and troubleshoot problematic stations remotely. In the event of an emergency or maintenance on the server hardware, data acquisition can be shifted to alternate data centers through the use of virtualization technologies.

International Space Station (ISS)

NASA Image and Video Library

1994-07-20

An artist's conception of what the final configuration of the International Space Station (ISS) will look like when it is fully built and deployed. The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experimentation.

Outdoor field experience with autonomous RPC based stations

NASA Astrophysics Data System (ADS)

Lopes, L.; Assis, P.; Blanco, A.; Carolino, N.; Cerda, M. A.; Conceição, R.; Cunha, O.; Ferreira, M.; Fonte, P.; Luz, R.; Mendes, L.; Pereira, A.; Pimenta, M.; Sarmento, R.; Tomé, B.

2016-09-01

In the last two decades Resistive Plate Chambers were employed in the Cosmic Ray Experiments COVER-PLASTEX and ARGO/YBJ. In both experiments the detectors were housed indoors, likely owing to gas distribution requirements and the need to control environment variables that directly affect RPCs operational stability. But in experiments where Extended Air Shower (EAS) sampling is necessary, large area arrays composed by dispersed stations are deployed, rendering this kind of approach impossible. In this situation, it would be mandatory to have detectors that could be deployed in small standalone stations, with very rare opportunities for maintenance, and with good resilience to environmental conditions. Aiming to meet these requirements, we started some years ago the development of RPCs for Autonomous Stations. The results from indoor tests and measurements were very promising, both concerning performance and stability under very low gas flow rate, which is the main requirement for Autonomous Stations. In this work we update the indoor results and show the first ones concerning outdoor stable operation. In particular, a dynamic adjustment of the high voltage is applied to keep gas gain constant.

Quantifying the Benefits of Shallow Posthole Installation for the Future French Permanent Broadband Stations

NASA Astrophysics Data System (ADS)

Vergne, J.; Charade, O.; Bonaime, S.; Louis-Xavier, T.; Arnold, B.

2015-12-01

In the framework of the RESIF (réseau sismologique et géodésique français) infrastructure, more than one hundred new permanent broadband stations have to be deployed in metropolitan France within the forthcoming years. This requires a standardized installation method able to provide good noise level performance at a reasonable cost, especially for the 60 percent of stations that we expect to be settled in open environments. During the last two years we tested various types of sensor's hosting infrastructures with a strong focus on recently released posthole sensors that can be deployed at the bottom of shallow boreholes. Tests were performed at 3 different sites (two GEOSCOPE stations and a dedicated open-field prototype site) with geological conditions spanning from hard rocks to very soft soils. On each site, posthole sensors were deployed at different depths, from the surface to a maximum of 20m deep, and in different types of casing. Moreover, a reference sensor, either installed in a tunnel, a cellar or a seismic vault, has been operated continuously. We present a comprehensive comparison of the seismic noise level measured in the different hosting infrastructures and for several frequency bands corresponding to various sources of noise. At high and low frequencies, seismic noise level in some boreholes equals or outperforms the one obtained for the reference sensors. Between 0.005 and 0.05Hz, we observe a strong decrease of seismic noise level on the horizontal components in the deepest boreholes compared to near surface installations. This improvement can reach up to 30dB and is mostly due to a reduction in tilt noise induced by wind or local pressure variations. However, the absolute noise level that can be achieved clearly depends on the local geology. All these tests, together with estimated installation costs, point toward the deployment of sensors in shallow boreholes at the future French broadband stations located in open environments.

Measuring Evapotranspiration in Urban Irrigated Lawns in Two Kansas Cities

NASA Astrophysics Data System (ADS)

Shonkwiler, K. B.; Bremer, D.; Ham, J. M.

2011-12-01

Conservation of water is becoming increasingly critical in many metropolitan areas. The use of automated irrigation systems for the maintenance of lawns and landscapes is rising and these systems are typically maladjusted to apply more water than necessary, resulting in water wastage. Provision of accurate estimates of actual lawn water use may assist urbanites in conserving water through better adjustment of automatic irrigation systems. Micrometeorological methods may help determine actual lawn water use by measuring evapotranspiration (ET) from urban lawns. From April - August of 2011, four small tripod-mounted weather stations (tripods, five total) were deployed in twelve residential landscapes in the Kansas cities of Manhattan (MHK) and Wichita (ICT) in the USA (six properties in each city). Each tripod was instrumented to estimate reference crop evapotranspiration (ETo) via the FAO-56 method. During tripod deployment in residential lawns, actual evapotranspiration (ETactual) was measured nearby using a stationary, trailer-mounted eddy covariance (EC) station. The EC station sampled well-watered turf at the K-State Rocky Ford Turfgrass Center within 5 km of the study properties in MHK, and was also deployed at a commercial sod farm 15 - 40 km from the study residences in the greater ICT metro area. The fifth tripod was deployed in the source area of the EC station to estimate ETo in conjunction with tripods in the lawns (i.e., to serve as a reference). Data from EC allowed for computation of a so-called lawn coefficient (Kc) by determining the ratio of ETo from the tripods in residential lawns to ETo from the EC station (ETo,EC); hence, Kc = ETo,tripod / ETo,EC. Using this method, ETactual can be estimated for individual tripods within a lawn. Data suggests that it may be more accurate to quantify ET within individual lawns by microclimate (i.e., determine coefficients for "shaded" and "open/unshaded" portions of a lawn). By finding microclimate coefficients, estimates of ETactual for individual lawns can be tailored to the specific characteristics of each property.

Three small deployed satellites

NASA Image and Video Library

2012-10-04

ISS033-E-009282 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. Earth’s horizon and the blackness of space provide the backdrop for the scene.

JEMRMS Small Satellite Deployment Observation

NASA Image and Video Library

2012-10-04

ISS033-E-009315 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A blue and white part of Earth provides the backdrop for the scene.

Imaging shallow magma chambers at Alaskan volcanoes with ambient seismic noise

NASA Astrophysics Data System (ADS)

Haney, M. M.; Prejean, S. G.

2009-05-01

Ambient noise tomography/inversion (ANT) is an emerging technique in seismology with the ability to provide 3D images of subsurface volcanic structure using relatively sparse seismic networks. The method relies on the principle that the cross-correlation of noise recordings at two different seismic stations reproduces an experiment in which one of the stations acts as an active source. Ambient seismic noise in the frequency band from 0.1 to 1 Hz is mostly composed of fundamental mode surface waves, of both Love and Rayleigh type. As a result, noise cross-correlations are sensitive to shear-wave structure and complement compressional-wave images computed from phase arrivals of local earthquakes. At Okmok volcano in the Aleutian islands, a 3D image constructed from 40 days of noise recordings in 2005 on a 12 station network clearly shows two low velocity zones (LVZs) centered about the 10-km-wide caldera: a shallow zone in the upper 1-2 km and a deeper zone between 4-4.5 km. The shallow LVZ is interpreted to be weak, poorly-consolidated material within the caldera; the deeper LVZ is indicative of the shallow magma chamber at Okmok. That the chamber is imaged as an LVZ in 2005 points to it remaining in a molten state throughout the time period between the 1997 and 2008 eruptions. The existence of a shallow chamber at Okmok is consistent with independent studies based on GPS, InSAR, and petrologic data. A 3D image has also been determined for the Katmai group of volcanoes along the Alaska peninsula from 60 days of continuous recordings in 2005 and 2006. An LVZ at Katmai Pass, previously known from local earthquake tomography (LET), is evident in the 3D shear-wave velocity model at depths down to 2 km BSL. That the LVZ exists in compressional-wave velocity models suggests it is a shallow magma storage area for Trident volcano. In contrast, low shear-wave velocity under Martin volcano is likely fluid-related, given the lack of low compressional-wave velocities in images derived from LET. Interestingly, a deep (> 5 km), subtle LVZ imaged between Trident and Mount Katmai may represent remnants of the magmatic conduit system from the cataclysmic 1912 eruption of Novarupta. A deployment of 11 temporary broadband seismometers are currently in place around Katmai Pass and should provide more constraints on the structure of the deep LVZ. The availability of many three-component seismometers within the Katmai permanent/temporary network makes it possible to additionally invert Love waves and the ratio of the horizontal-to-vertical motion of Rayleigh waves, the HV ratio, to further delineate volcanic structure from the ambient seismic field.

Modelling a reliable wind/PV/storage power system for remote radio base station sites without utility power

NASA Astrophysics Data System (ADS)

Bitterlin, Ian F.

The development of photovoltaic (PV) cells has made steady progress from the early days, when only the USA space program could afford to deploy them, to now, seeing them applied to roadside applications even in our Northern European climes. The manufacturing cost per watt has fallen and the daylight-to-power conversion efficiency increased. At the same time, the perception that the sun has to be directly shining on it for a PV array to work has faded. On some of those roadside applications, particularly for remote emergency telephones or for temporary roadwork signage where a utility electrical power connection is not practical, the keen observer will spot, usually in addition to a PV array, a small wind-turbine and an electrical cabinet quite obviously (by virtue of its volume) containing a storage battery. In the UK, we have the lions share (>40%) of Europe's entire wind power resource although, despite press coverage of the "anti-wind" lobby to the contrary, we have hardly started to harvest this clean and free energy source. Taking this (established and proven) roadside solution one step further, we will consider higher power applications. A cellular phone system is one where a multitude of remote radio base stations (RBS) are required to provide geographical coverage. With networks developing into the so called "3G" technologies the need for base stations has tripled, as each 3G cell covers only 1/3 the geographical area of its "2G" counterpart. To cover >90% of the UK's topology (>97% population coverage) with 3G cellular technology will requires in excess of 12,000 radio base stations per operator network. In 2001, there were around 25,000 established sites and, with an anticipated degree of collocation by necessity, that figure is forecast to rise to >47,000. Of course, the vast majority of these sites have a convenient grid connection. However, it is easy to see that the combination of wind and PV power generation and an energy storage system may be an interesting solution for the more rural and remote applications - particularly those where an electrical supply is not available or practical - and this paper attempts to explore the current practicalities of such a power generation solution for those cellular phone base stations.

Crustal and mantle structure beneath the Terre Adélie Craton, East Antarctica: insights from receiver function and seismic anisotropy measurements

NASA Astrophysics Data System (ADS)

Lamarque, Gaëlle; Barruol, Guilhem; Fontaine, Fabrice R.; Bascou, Jérôme; Ménot, René-Pierre

2015-02-01

The Terre Adélie and George V Land (East Antarctica) represent key areas for understanding tectonic relationships between terranes forming the Neoarchean-Palaeoproterozoic Terre Adélie Craton (TAC) and the neighbouring lithospheric blocks, together with the nature of its boundary. This region that represents the eastern border of the TAC is limited on its eastern side by the Mertz shear zone (MSZ) separating more recent Palaeozoic units from the craton. The MSZ, that recorded dextral strike-slip movement at 1.7 and 1.5 Ga, is likely correlated with the Kalinjala or Coorong shear zone in South Australia, east of the Gawler Craton and may therefore represent a frozen lithospheric-scale structure. In order to investigate the lithospheric structure of the TAC and the MSZ, we deployed from 2009 October to 2011 October four temporary seismic stations, which sampled the various lithospheric units of the TAC and of the neighbouring Palaeozoic block, together with the MSZ. We used receiver function method to deduce Moho depths and seismic anisotropy technique to infer the upper mantle deformation. Results from receiver functions analysis reveal Moho at 40-44 km depth beneath the TAC, at 36 km under the MSZ and at 28 km beneath the eastern Palaeozoic domain. The MSZ therefore delimits two crustal blocks of different thicknesses with a vertical offset of the Moho of 12 km. Seismic anisotropy deduced from SKS splitting at stations on the TAC shows fast polarisation directions (Φ) trending E-W, that is, parallel to the continental margin, and delay times (δt) ranging from 0.8 to 1.6 s. These results are similar to the splitting parameters observed at the permanent GEOSCOPE Dumont D'Urville station (DRV: Φ 95°N, δt 1.1 s) located in the Palaeoproterozoic domain of TAC. On the MSZ, the small number of good quality measurements limits the investigation of the deep signature of the shear zone. However, the station in the Palaeozoic domain shows Φ trending N60°E, which is significantly different to the Φ trending measurements from stations on the TAC, suggesting that the MSZ may also represent a major frontier between the Neoarchean-Palaeoproterozoic and Palaeozoic terranes.

Phase-Change Thermoplastic Elastomer Blends for Tunable Shape Memory by Physical Design

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

Mineart, Kenneth P.; Tallury, Syamal S.; Li, Tao

Shape-memory polymers (SMPs) change shape upon exposure to an environmental stimulus.1-3 They are of considerable importance in the ongoing development of stimuli-responsive biomedical4,5 and deployable6 devices, and their function depends on the presence of two components.7 The first provides mechanical rigidity to ensure retention of one or more temporary strain states and also serves as a switch capable of releasing a temporary strain state. The second, a network-forming component, is required to restore the polymer to a prior strain state upon stimulation. In thermally-activated SMPs, the switching element typically relies on a melting or glass transition temperature,1-3,7 and broad ormore » multiple switches permit several temporary strain states.8-10 Chemical integration of network-forming and switching species endows SMPs with specific properties.8,10,11 Here, we demonstrate that phase-change materials incorporated into network-forming macromolecules yield shape-memory polymer blends (SMPBs) with physically tunable switching temperatures and recovery kinetics for use in multi-responsive laminates and shape-change electronics.« less

iss050e037283

NASA Image and Video Library

2017-01-31

iss050e037283 (01/31/2017) --- NASA astronaut Peggy Whitson removes the Multi-Purpose Experiment Platform (MPEP) from inside the Kibo airlock aboard the International Space Station. The airlock is used to deploy a number of scientific payloads from inside the station out into the vacuum of space.

Two-tier tube-trailer pressure consolidation operation method for hydrogen refueling station cost reduction

DOE PAGES

Reddi, Krishna; Elgowainy, Amgad; Rustagi, Neha; ...

2018-01-10

An operation strategy known as two-tier “pressure consolidation” of delivered tube-trailers (or equivalent supply storage) has been developed to maximize the throughput at gaseous hydrogen refueling stations (HRSs) for fuel cell electric vehicles (FCEVs). The high capital costs of HRSs and the consequent high investment risk are deterring growth of the infrastructure needed to promote the deployment of FCEVs. Stations supplied by gaseous hydrogen will be necessary for FCEV deployment in both the near and long term. Here, the two-tier pressure consolidation method enhances gaseous HRSs in the following ways: (1) reduces the capital cost compared with conventional stations, asmore » well as those operating according to the original pressure consolidation approach described by Elgowainy et al. (2014) [1], (2) minimizes pressure cycling of HRS supply storage relative to the original pressure consolidation approach; and (3) increases use of the station’s supply storage (or delivered tube-trailers) while maintaining higher state-of-charge vehicle fills.« less

Impact of public electric vehicle charging infrastructure

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

Levinson, Rebecca S.; West, Todd H.

Our work uses market analysis and simulation to explore the potential of public charging infrastructure to spur US battery electric vehicle (BEV) sales, increase national electrified mileage, and lower greenhouse gas (GHG) emissions. By employing both scenario and parametric analysis for policy driven injection of public charging stations we find the following: (1) For large deployments of public chargers, DC fast chargers are more effective than level 2 chargers at increasing BEV sales, increasing electrified mileage, and lowering GHG emissions, even if only one DC fast charging station can be built for every ten level 2 charging stations. (2) Amore » national initiative to build DC fast charging infrastructure will see diminishing returns on investment at approximately 30,000 stations. (3) Some infrastructure deployment costs can be defrayed by passing them back to electric vehicle consumers, but once those costs to the consumer reach the equivalent of approximately 12¢/kWh for all miles driven, almost all gains to BEV sales and GHG emissions reductions from infrastructure construction are lost.« less

Two-tier tube-trailer pressure consolidation operation method for hydrogen refueling station cost reduction

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

Reddi, Krishna; Elgowainy, Amgad; Rustagi, Neha

An operation strategy known as two-tier “pressure consolidation” of delivered tube-trailers (or equivalent supply storage) has been developed to maximize the throughput at gaseous hydrogen refueling stations (HRSs) for fuel cell electric vehicles (FCEVs). The high capital costs of HRSs and the consequent high investment risk are deterring growth of the infrastructure needed to promote the deployment of FCEVs. Stations supplied by gaseous hydrogen will be necessary for FCEV deployment in both the near and long term. Here, the two-tier pressure consolidation method enhances gaseous HRSs in the following ways: (1) reduces the capital cost compared with conventional stations, asmore » well as those operating according to the original pressure consolidation approach described by Elgowainy et al. (2014) [1], (2) minimizes pressure cycling of HRS supply storage relative to the original pressure consolidation approach; and (3) increases use of the station’s supply storage (or delivered tube-trailers) while maintaining higher state-of-charge vehicle fills.« less

Impact of public electric vehicle charging infrastructure

DOE PAGES

Levinson, Rebecca S.; West, Todd H.

2017-10-16

Our work uses market analysis and simulation to explore the potential of public charging infrastructure to spur US battery electric vehicle (BEV) sales, increase national electrified mileage, and lower greenhouse gas (GHG) emissions. By employing both scenario and parametric analysis for policy driven injection of public charging stations we find the following: (1) For large deployments of public chargers, DC fast chargers are more effective than level 2 chargers at increasing BEV sales, increasing electrified mileage, and lowering GHG emissions, even if only one DC fast charging station can be built for every ten level 2 charging stations. (2) Amore » national initiative to build DC fast charging infrastructure will see diminishing returns on investment at approximately 30,000 stations. (3) Some infrastructure deployment costs can be defrayed by passing them back to electric vehicle consumers, but once those costs to the consumer reach the equivalent of approximately 12¢/kWh for all miles driven, almost all gains to BEV sales and GHG emissions reductions from infrastructure construction are lost.« less

Scaling an in situ network for high resolution modeling during SMAPVEX15

NASA Astrophysics Data System (ADS)

Coopersmith, E. J.; Cosh, M. H.; Jacobs, J. M.; Jackson, T. J.; Crow, W. T.; Holifield Collins, C.; Goodrich, D. C.; Colliander, A.

2015-12-01

Among the greatest challenges within the field of soil moisture estimation is that of scaling sparse point measurements within a network to produce higher resolution map products. Large-scale field experiments present an ideal opportunity to develop methodologies for this scaling, by coupling in situ networks, temporary networks, and aerial mapping of soil moisture. During the Soil Moisture Active Passive Validation Experiments in 2015 (SMAPVEX15) in and around the USDA-ARS Walnut Gulch Experimental Watershed and LTAR site in southeastern Arizona, USA, a high density network of soil moisture stations was deployed across a sparse, permanent in situ network in coordination with intensive soil moisture sampling and an aircraft campaign. This watershed is also densely instrumented with precipitation gages (one gauge/0.57 km2) to monitor the North American Monsoon System, which dominates the hydrologic cycle during the summer months in this region. Using the precipitation and soil moisture time series values provided, a physically-based model is calibrated that will provide estimates at the 3km, 9km, and 36km scales. The results from this model will be compared with the point-scale gravimetric samples, aircraft-based sensor, and the satellite-based products retrieved from NASA's Soil Moisture Active Passive mission.

Upper mantle anisotropic attenuation of the Sierra Nevada and surroundings

NASA Astrophysics Data System (ADS)

Bernardino, M. J.; Jones, C. H.; Monsalve, G.

2016-12-01

We investigate the contribution of anelasticity in the generation of seismic velocity variations within the upper mantle of the Sierra Nevada and surrounding regions through teleseismic shear-wave attenuation. Given that anelastic effects are most sensitive to temperature and hydration and less to composition and small degrees of partial melt, we aim constrain the thermal structure beneath this region and identify locations where elevated upper mantle temperatures dominate. We also investigate the dependence of shear-wave attenuation on direction by accounting for seismic anisotropy in our measurements. S-wave t* values are determined from teleseismic S- and SKS- phases recorded on permanent and temporary deployments within the California region with particular focus on the Sierra Nevada Earthscope Project (SNEP) and the Sierran Paradox Experiment (SPE) stations. S-waveforms are rotated into the Sierran SFast, N75°E, and SSlow, N15°W, components. Following the method of Stachnik et al., (2004), S-wave spectra for each event are jointly inverted for a single seismic moment, M0k, and corner frequency, fck, for each event, and separate t* for each ray path. The resulting t*Fast and t*Slow measurements are then inverted for three-dimensional variations in (1/QFast) and (1/QSlow). Results are compared with previous magnetotelluric, surface heat flow, and body-wave velocity inversion studies.

Properties of Repetitive Long-Period Seismicity at Villarrica Volcano, Chile

NASA Astrophysics Data System (ADS)

Richardson, J.; Waite, G. P.; Palma, J.; Johnson, J. B.

2011-12-01

Villarrica Volcano, Chile hosts a persistent lava lake and is characterized by degassing and long-period seismicity. In order to better understand the relationship between outgassing and seismicity, we recorded broadband seismic and acoustic data along with high-rate SO2 emission data. We used both a densely-spaced linear array deployed on the northern flank of Villarrica, during the austral summer of 2011, and a wider aperture array of stations distributed around the volcano that was active in the austral summer of 2010. Both deployments consisted of three-component broadband stations and were augmented with broadband infrasound sensors. Of particular interests are repetitive, ~1 Hz seismic and coincident infrasound signals that occurred approximately every 2 minutes. Because these events are typically very low amplitude, we used a matched filter approach to identify them. We windowed several high-amplitude records of these events from broadband seismic stations near the vent. The record section of each event served as a template to compare with the entire dataset by cross-correlation. This approach identified ~20,000 nearly identical events during the ~7 day deployment of the linear array, which were otherwise difficult to identify in the raw records. Assuming that all of the events that we identified have identical source mechanisms and depths, we stack the large suite of events to produce low-noise records and particle motions at receivers farther than 5 km from the vent. We find that the records from stations near the edifice are dominated by tangential particle motion, suggesting the influence of near-field components. Correlation of these data with broadband acoustic data collected at the summit suggest that these repeatable seismic processes are linked to acoustic emissions, probably due to gas bubbles bursting at the magma free surface, as no eruptive products besides gas were being emitted by the volcano during the instrument deployment. The acoustic signals affiliated with the repetitive seismic signals do not seem directly related to the continuous, well-correlated acoustic tremor observed both at the vent and at roughly 6 km away from small-aperture acoustic arrays (also reported by other groups in 2009, 2010). We also correlate the acoustic and repetitive seismic signals with high time resolution (~1 Hz sampling rate), sulfur dioxide emissions measured with an ultraviolet camera. Because a subset of stations operated during both 2010 and 2011, we could tie events from both deployments to generate a single stacked event at all 17 stations. We will present results of finite-difference modeling of this event stack using a simple homogeneous velocity structure.

The Askaryan Radio Array: Overview and Recent Results

NASA Astrophysics Data System (ADS)

Pfendner, Carl; Askaryan Radio Array (ARA) Collaboration

2017-01-01

The Askaryan Radio Array (ARA) is radio frequency observatory under construction at the South Pole that is searching for ultrahigh energy neutrinos via the Askaryan effect. By instrumenting several gigatons of Antarctic glacial ice, the experiment aims to detect a flux of neutrinos above 10 PeV in energy. The measurement of this expected flux of neutrinos would provide information about the highest energy processes in the universe with no local horizon. The full detector consisting of 37 stations is being constructed in a phased deployment with 3 stations already in place and two more planned for deployment in the 2017-2018 season. Recent results from an analysis of data from two stations and a search for neutrinos correlated with gamma ray bursts are presented here. Funding provided by NSF CAREER Award 1255557, NSF ARA Grant 1404266, BigData Grant 1250720.

Art Concepts- Skylab (Sun Shade)

NASA Image and Video Library

1973-05-18

S73-26127 (1973) --- An artist's concept of the Skylab space station cluster in Earth orbit illustrating the deployment of the twin pole thermal shield to shade the Orbital Workshop (OWS) from the sun. This is one of the sunshade possibilities considered to solve the problem of the overheated OWS. Here the two Skylab 2 astronauts have completely deployed the sunshade. Note the evidence of another Skylab problem - the solar panels on the OWS are not deployed as required. Photo credit: NASA

Newberry Seismic Deployment Fieldwork Report

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

Wang, J; Templeton, D C

2012-03-21

This report summarizes the seismic deployment of Lawrence Livermore National Laboratory (LLNL) Geotech GS-13 short-period seismometers at the Newberry Enhanced Geothermal System (EGS) Demonstration site located in Central Oregon. This Department of Energy (DOE) demonstration project is managed by AltaRock Energy Inc. AltaRock Energy had previously deployed Geospace GS-11D geophones at the Newberry EGS Demonstration site, however the quality of the seismic data was somewhat low. The purpose of the LLNL deployment was to install more sensitive sensors which would record higher quality seismic data for use in future seismic studies, such as ambient noise correlation, matched field processing earthquakemore » detection studies, and general EGS microearthquake studies. For the LLNL deployment, seven three-component seismic stations were installed around the proposed AltaRock Energy stimulation well. The LLNL seismic sensors were connected to AltaRock Energy Gueralp CMG-DM24 digitizers, which are powered by AltaRock Energy solar panels and batteries. The deployment took four days in two phases. In phase I, the sites were identified, a cavity approximately 3 feet deep was dug and a flat concrete pad oriented to true North was made for each site. In phase II, we installed three single component GS-13 seismometers at each site, quality controlled the data to ensure that each station was recording data properly, and filled in each cavity with native soil.« less

Solar Weather Ice Monitoring Station (SWIMS). A low cost, extreme/harsh environment, solar powered, autonomous sensor data gathering and transmission system

NASA Astrophysics Data System (ADS)

Chetty, S.; Field, L. A.

2013-12-01

The Arctic ocean's continuing decrease of summer-time ice is related to rapidly diminishing multi-year ice due to the effects of climate change. Ice911 Research aims to develop environmentally respectful materials that when deployed will increase the albedo, enhancing the formation and/preservation of multi-year ice. Small scale deployments using various materials have been done in Canada, California's Sierra Nevada Mountains and a pond in Minnesota to test the albedo performance and environmental characteristics of these materials. SWIMS is a sophisticated autonomous sensor system being developed to measure the albedo, weather, water temperature and other environmental parameters. The system (SWIMS) employs low cost, high accuracy/precision sensors, high resolution cameras, and an extreme environment command and data handling computer system using satellite and terrestrial wireless communication. The entire system is solar powered with redundant battery backup on a floating buoy platform engineered for low temperature (-40C) and high wind conditions. The system also incorporates tilt sensors, sonar based ice thickness sensors and a weather station. To keep the costs low, each SWIMS unit measures incoming and reflected radiation from the four quadrants around the buoy. This allows data from four sets of sensors, cameras, weather station, water temperature probe to be collected and transmitted by a single on-board solar powered computer. This presentation covers the technical, logistical and cost challenges in designing, developing and deploying these stations in remote, extreme environments. Image captured by camera #3 of setting sun on the SWIMS station One of the images captured by SWIMS Camera #4

Deployment of sustainable fueling/charging systems at California highway safety roadside rest areas : a research report from the National Center for Sustainable Transportation.

DOT National Transportation Integrated Search

2016-12-01

The objectives of this research were to study the feasibility of the deployment of renewable hydrogen fueling/DC fast charging stations at California Safety Roadside Rest Areas (SRRAs), not at service areas with commercial activity, and the integrati...

Microspacecraft and Earth observation: Electrical field (ELF) measurement project

NASA Technical Reports Server (NTRS)

Olsen, Tanya; Elkington, Scot; Parker, Scott; Smith, Grover; Shumway, Andrew; Christensen, Craig; Parsa, Mehrdad; Larsen, Layne; Martinez, Ranae; Powell, George

1990-01-01

The Utah State University space system design project for 1989 to 1990 focuses on the design of a global electrical field sensing system to be deployed in a constellation of microspacecraft. The design includes the selection of the sensor and the design of the spacecraft, the sensor support subsystems, the launch vehicle interface structure, on board data storage and communications subsystems, and associated ground receiving stations. Optimization of satellite orbits and spacecraft attitude are critical to the overall mapping of the electrical field and, thus, are also included in the project. The spacecraft design incorporates a deployable sensor array (5 m booms) into a spinning oblate platform. Data is taken every 0.1 seconds by the electrical field sensors and stored on-board. An omni-directional antenna communicates with a ground station twice per day to down link the stored data. Wrap-around solar cells cover the exterior of the spacecraft to generate power. Nine Pegasus launches may be used to deploy fifty such satellites to orbits with inclinations greater than 45 deg. Piggyback deployment from other launch vehicles such as the DELTA 2 is also examined.

KENNEDY SPACE CENTER, FLA. - STS-115 Mission Specialist Heidemarie Stefanyshyn-Piper talks to workers in the Space Station Processing Facility. She and other crew members are at KSC for hardware familiarization. The mission will deliver the second port truss segment, the P3/P4 Truss, to attach to the first port truss segment, the P1 Truss, as well as deploy solar array sets 2A and 4A.. The crew is scheduled to activate and check out the Solar Alpha Rotary Joint (SARJ) and deploy the P4 Truss radiator.

NASA Image and Video Library

2003-07-18

KENNEDY SPACE CENTER, FLA. - STS-115 Mission Specialist Heidemarie Stefanyshyn-Piper talks to workers in the Space Station Processing Facility. She and other crew members are at KSC for hardware familiarization. The mission will deliver the second port truss segment, the P3/P4 Truss, to attach to the first port truss segment, the P1 Truss, as well as deploy solar array sets 2A and 4A.. The crew is scheduled to activate and check out the Solar Alpha Rotary Joint (SARJ) and deploy the P4 Truss radiator.

78 FR 20128 - Extension of the Designation of Nicaragua for Temporary Protected Status

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-03

... Nicaragua's roads are paved. Hurricane Mitch damaged potable water, sewage treatment systems, water uptake systems, wells, water pump stations, and pipes in Nicaragua. The storm floods and runoff polluted water... education facilities, water supply and sanitation facilities, and the agricultural sector. Living conditions...

41 CFR 105-53.132 - Civilian Board of Contract Appeals.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Force, the U.S. National Aeronautics and Space Administration, the U.S. Postal Service, the Postal Rate.... Department of Agriculture's Risk Management Agency (RMA) involving actions of the Federal Crop Insurance... official temporary duty travel, and expenses incurred in connection with relocation to a new duty station...

41 CFR 105-53.132 - Civilian Board of Contract Appeals.

Code of Federal Regulations, 2014 CFR

2014-01-01

... Force, the U.S. National Aeronautics and Space Administration, the U.S. Postal Service, the Postal Rate.... Department of Agriculture's Risk Management Agency (RMA) involving actions of the Federal Crop Insurance... official temporary duty travel, and expenses incurred in connection with relocation to a new duty station...

47 CFR 73.1680 - Emergency antennas.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Emergency antennas. 73.1680 Section 73.1680... Rules Applicable to All Broadcast Stations § 73.1680 Emergency antennas. (a) An emergency antenna is one that is erected for temporary use after the authorized main and auxiliary antennas are damaged and...

47 CFR 73.1680 - Emergency antennas.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 4 2013-10-01 2013-10-01 false Emergency antennas. 73.1680 Section 73.1680... Rules Applicable to All Broadcast Stations § 73.1680 Emergency antennas. (a) An emergency antenna is one that is erected for temporary use after the authorized main and auxiliary antennas are damaged and...

47 CFR 73.1680 - Emergency antennas.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false Emergency antennas. 73.1680 Section 73.1680... Rules Applicable to All Broadcast Stations § 73.1680 Emergency antennas. (a) An emergency antenna is one that is erected for temporary use after the authorized main and auxiliary antennas are damaged and...

47 CFR 73.1680 - Emergency antennas.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 4 2012-10-01 2012-10-01 false Emergency antennas. 73.1680 Section 73.1680... Rules Applicable to All Broadcast Stations § 73.1680 Emergency antennas. (a) An emergency antenna is one that is erected for temporary use after the authorized main and auxiliary antennas are damaged and...

47 CFR 73.1680 - Emergency antennas.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Emergency antennas. 73.1680 Section 73.1680... Rules Applicable to All Broadcast Stations § 73.1680 Emergency antennas. (a) An emergency antenna is one that is erected for temporary use after the authorized main and auxiliary antennas are damaged and...

78 FR 782 - Energy Northwest; Columbia Generating Station; Exemption

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-04

... health or safety, and are consistent with the common defense and security; and (2) when special... temporary relief from the applicable regulation and the licensee or applicant has made good faith efforts to... Common Defense and Security The proposed exemption would extend the time interval between the 2011 and...

Comparison and Analysis of Energy Performance of Baseline and Enhanced Temporary Army Shelters

DTIC Science & Technology

2015-09-01

modeling .................................................................................................... 37 4.4 Predicted vs. field- measured data...with remote access capability ......................... 35 4-2 Direct normal solar radiation measured at weather station and estimated with the... Measured global horizontal radiation and EnergyPlus calculated incident solar radiation on a horizontal surface

International Space Station (ISS)

NASA Image and Video Library

1994-12-16

Artist's concept of the International Space Station (ISS) Alpha deployed and operational. This figure also includes the docking procedures for the Space Shuttle (shown with cargo bay open). The ISS is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experimentation.

Space Station Freedom solar array containment box mechanisms

NASA Technical Reports Server (NTRS)

Johnson, Mark E.; Haugen, Bert; Anderson, Grant

1994-01-01

Space Station Freedom will feature six large solar arrays, called solar array wings, built by Lockheed Missiles & Space Company under contract to Rockwell International, Rocketdyne Division. Solar cells are mounted on flexible substrate panels which are hinged together to form a 'blanket.' Each wing is comprised of two blankets supported by a central mast, producing approximately 32 kW of power at beginning-of-life. During launch, the blankets are fan-folded and compressed to 1.5 percent of their deployed length into containment boxes. This paper describes the main containment box mechanisms designed to protect, deploy, and retract the solar array blankets: the latch, blanket restraint, tension, and guidewire mechanisms.

View taken during berthing of MPLM

NASA Image and Video Library

2005-08-05

ISS011-E-11517 (5 August 2005) --- Canadarm2 or the Space Station Remote Manipulator System arm grasps the Italian-built Multi-Purpose Logistics Module Raffaello to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the U.S. Lab, Destiny, on the international space station, Astronauts James M. Kelly, pilot, and Wendy B. Lawrence, mission specialist, were in control of the transfer. The MPLM was being moved from its temporary parking place on the Station's Unity node to the payload bay of Discovery for the return trip to Earth. The Discovery astronauts arrived nine days ago with tons of fresh supplies for the Station, and with much effort, replaced that space on Raffaello with unneeded materials from the orbital outpost.

Assessment of eruption intensity using infrasound waveform inversion at Mt. Etna, Italy.

NASA Astrophysics Data System (ADS)

Diaz Moreno, A.; Iezzi, A. M.; Lamb, O. D.; Zuccarello, L.; Fee, D.; De Angelis, S.

2017-12-01

Mt. Etna, Italy, a 3,330 m stratovolcano, is one of the most active volcanoes in the world. It is topped by five craters: Voragine, Bocca Nuova, the North-East, South-East, and New South-East Crater. Its activity during the past decade can be separated into two main types: i) nearly-continuous degassing interspersed by mild-to-vigorous Strombolian activity within the summit craters, and ii) effusive flank eruptions. In June 2017, we deployed a large temporary network of 14 infrasound sensors (Chaparral UHP60) and 12 broadband seismometers (Guralp EX-120s). We also recorded Thermal Infrared (TIR) and Unmanned Aerial Vehicle images of activity at the summit vents. Our primary objective is to quantify the intensity and mechanisms of infrasound sources at Mt. Etna, and use these results to improve models of volcanic plumes. From June 2017 until the time of writing, the infrasound network detected signals associated with nearly-continuous degassing and discrete small-to-moderate explosions originating at two distinct locations within the Voragine Crater and the New South-East Crater, respectively. During periods of increased explosive activity, we recorded 20-30 discrete events/day with infrasonic amplitudes of up to 7.5 Pa at 1 km distance from the active vent. The explosions exhibited sinusoidal acoustic waveforms, often with similar characteristics, durations of 1-3 s, and a 2 Hz peak frequency. Due to the relatively dense station coverage and the azimuthal distribution of the network, our deployment offers an opportunity to characterize, with unprecedented resolution, infrasound sources at Mt. Etna. Here we present preliminary results of 3D acoustic wave-field simulations, using a Finite Difference Time Domain modelling scheme, and a preliminary assessment of volumetric eruption rates through acoustic waveform inversion. We investigate the effects of local topography and atmospheric winds on the propagation of the acoustic wavefield, and discuss the implications for infrasound-based assessments of eruption intensity. Our network will be deployed through August 2017, with the hopes of catching larger and more diverse eruptions as well.

Three small deployed satellites

NASA Image and Video Library

2012-10-04

ISS033-E-009286 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A portion of the station’s solar array panels and a blue and white part of Earth provide the backdrop for the scene.

Three small deployed satellites

NASA Image and Video Library

2012-10-04

ISS033-E-009285 (4 Oct. 2012) --- Several tiny satellites are featured in this image photographed by an Expedition 33 crew member on the International Space Station. The satellites were released outside the Kibo laboratory using a Small Satellite Orbital Deployer attached to the Japanese module’s robotic arm on Oct. 4, 2012. Japan Aerospace Exploration Agency astronaut Aki Hoshide, flight engineer, set up the satellite deployment gear inside the lab and placed it in the Kibo airlock. The Japanese robotic arm then grappled the deployment system and its satellites from the airlock for deployment. A portion of the station’s solar array panels and a blue and white part of Earth provide the backdrop for the scene.

Transfer of the MPLM Leonardo from the ISS to the Orbiter Discovery Payload Bay

NASA Image and Video Library

2006-07-14

ISS013-E-51269 (14 July 2006) --- Canadarm2 or the Space Station Remote Manipulator System (SSRMS) arm (out of frame) grasps the Italian-built Multi-Purpose Logistics Module Leonardo to place it back in Discovery's cargo bay. On the other end of the arm, inside the shirt sleeve environment of the Destiny laboratory on the International Space Station, astronauts Stephanie D. Wilson and Lisa M. Nowak, STS-121 mission specialists, were in control of the transfer. The MPLM was being moved from its temporary parking place on the station's Unity node to the payload bay of Discovery for the return trip to Earth. Discovery's vertical stabilizer is at left.

CDR Cockrell in U.S. Laboratory /Destiny rack

NASA Image and Video Library

2001-02-11

STS98-E-5149 (11 February 2001) --- Astronaut Kenneth D. Cockrell, STS-98 commander, emerges from behind temporary covering in the newly attached Destiny laboratory onboard the International Space Station (ISS). After the Destiny hatch was opened early in the day, members of both crews went to work quickly inside the new module, activating air systems, fire extinguishers, alarm systems, computers and internal communications. The crews also took some photos and continued equipment transfers from the shuttle to the station. The scene was taken with a digital still camera.

Comparison of Temporary Open Arterial Revascularization Using Stent Grafts vs. Standard Vascular Shunts in a Porcine (Sus scrofa) Model

DTIC Science & Technology

2017-01-24

Objectives: Open surgical reconstruction using expanded polytetrafluoroethylene stent grafts to create a sutureless anastomosis is an alternative to...French Argyle shunt was inserted into one randomly assigned artery, with a self-expanding ePTFE stent deployed in the other. Arterial flow measurements...for histopathology were obtained during the terminal procedure. Results: Angiography revealed no difference in patency at 72 hours. The stent grafts

Improved earthquake monitoring in the central and eastern United States in support of seismic assessments for critical facilities

USGS Publications Warehouse

Leith, William S.; Benz, Harley M.; Herrmann, Robert B.

2011-01-01

Evaluation of seismic monitoring capabilities in the central and eastern United States for critical facilities - including nuclear powerplants - focused on specific improvements to understand better the seismic hazards in the region. The report is not an assessment of seismic safety at nuclear plants. To accomplish the evaluation and to provide suggestions for improvements using funding from the American Recovery and Reinvestment Act of 2009, the U.S. Geological Survey examined addition of new strong-motion seismic stations in areas of seismic activity and addition of new seismic stations near nuclear power-plant locations, along with integration of data from the Transportable Array of some 400 mobile seismic stations. Some 38 and 68 stations, respectively, were suggested for addition in active seismic zones and near-power-plant locations. Expansion of databases for strong-motion and other earthquake source-characterization data also was evaluated. Recognizing pragmatic limitations of station deployment, augmentation of existing deployments provides improvements in source characterization by quantification of near-source attenuation in regions where larger earthquakes are expected. That augmentation also supports systematic data collection from existing networks. The report further utilizes the application of modeling procedures and processing algorithms, with the additional stations and the improved seismic databases, to leverage the capabilities of existing and expanded seismic arrays.

Catheter Ablation of Focal Atrial Tachycardia Using Remote Magnetic Navigation.

PubMed

Webster, Mark; Pasupati, Sanjeevan; Lever, Nigel; Stiles, Martin

2018-05-01

This first-in-human study evaluated the safety and technical feasibility of the Tempo temporary cardiac pacing lead (BioTrace Medical), which includes a novel fixation mechanism and soft tip. Complications of temporary pacing leads include dislodgment, arrhythmias, and ventricular perforation. Temporary pacing applications have increased with transcatheter aortic valve replacement (TAVR) growth, for rapid pacing during balloon valvuloplasty (BAV) and valve deployment, and for periprocedural bradyarrhythmia support. Eligible patients required temporary pacing for TAVR, BAV, or electrophysiology (EP) procedures. Transthoracic echocardiograms were obtained at baseline and 24 hours after lead removal. Safety was defined as freedom from pericardial effusion requiring intervention or evidence of tamponade. Technical feasibility involved successful intracardiac delivery and pace capture. Additional evaluations included pacing threshold (PCT), rapid pacing, dislodgment, or sustained ventricular arrhythmias. Follow-up was to 30 days. Twenty-five patients (60% female; mean age, 64 ± 19 years) underwent 13 TAVRs (7 Sapien 3 valves [Edwards Lifesciences], 4 CoreValves [Medtronic], and 2 Lotus valves [Boston Scientific]), 11 EP procedures, and 1 BAV at two New Zealand centers from January 2016 to June 2016. Safety was met in all patients, with no device-related adverse events. Technical feasibility was achieved in 23 cases (92%); 2 patients had unsuitable anatomy. No patient had lead dislodgment or sustained ventricular arrhythmias, and the final procedural PCT was 0.7 ± 0.5 mA. Rapid pacing was successful in all cases. Five patients had successful postprocedural use up to 5 days. This first-in-human study demonstrates the safety and technical feasibility of the Tempo lead, providing stable periprocedural temporary pacing support.

Mir Cooperative Solar Array

NASA Technical Reports Server (NTRS)

Skor, Mike; Hoffman, Dave J.

1997-01-01

The Mir Cooperative Solar Array (MCSA), produced jointly by the United States and Russia, was deployed on the Mir Russian space station on May 25, 1996. The MCSA is a photovoltaic electrical power system that can generate up to 6 kW. The power from the MCSA is needed to extend Mir's lifetime and to support experiments conducted there by visiting U.S. astronauts. The MCSA was brought to Mir via the Space Shuttle Atlantis on the STS-74 mission, launched November 12, 1995. This cooperative venture combined the best technology of both countries: the United States provided high-efficiency, lightweight photovoltaic panel modules, whereas Russia provided the array structure and deployment mechanism. Technology developed in the Space Station Freedom Program, and now being used in the International Space Station, was used to develop MCSA's photovoltaic panel. Performance data obtained from MCSA operation on Mir will help engineers better understand the performance of the photovoltaic panel modules in orbit. This information will be used to more accurately predict the performance of the International Space Station solar arrays. Managed by the NASA Lewis Research Center for NASA's International Space Station Program Office in Houston, Texas, the MCSA Project was completed on time and under budget despite a very aggressive schedule.

Skylab 3,Skylab as the CM moves in for docking

NASA Image and Video Library

1973-07-28

SL3-114-1683 (28 July 1973) --- A close-up view of the Skylab space station photographed against an Earth background from the Skylab 3 Command and Service Modules (CSM) during station-keeping maneuvers prior to docking. Aboard the Command Module (CM) were astronauts Alan L. Bean, Owen K. Garriott and Jack R. Lousma, who remained with the Skylab Space Station in Earth orbit for 59 days. This picture was taken with a hand-held 70mm Hasselblad camera using a 100mm lens and SO-368 medium speed Ektachrome film. Note the one solar array system wing on the Orbital Workshop (OWS) which was successfully deployed during extravehicular activity (EVA) on the first manned Skylab flight. The parasol solar shield which was deployed by the Skylab 2 crew can be seen through the support struts of the Apollo Telescope Mount (ATM). Photo credit: NASA

Launch Deployment Assembly Human Engineering Analysis

NASA Technical Reports Server (NTRS)

Loughead, T.

1996-01-01

This report documents the human engineering analysis performed by the Systems Branch in support of the 6A cargo element design. The human engineering analysis is limited to the extra vehicular activities (EVA) which are involved in removal of various cargo items from the LDA and specific activities concerning deployment of the Space Station Remote Manipulator System (SSRMS).

s73-26128

NASA Image and Video Library

2013-10-23

S73-26128 (1973) --- An artist's concept of the Skylab space station cluster in Earth orbit illustrating the deployment of the twin pole thermal shield to shade the Orbital Workshop (OWS) from the sun. This is one of the sunshade possibilities considered to solve the problem of the overheated OWS. In this view the Skylab astronauts have partially deployed the sunshade. Photo credit: NASA

International postseismic response after the Mw=7.8 April 16, 2016 Pedernales Earthquake in Ecuador

NASA Astrophysics Data System (ADS)

Font, Y.; Ruiz, M. C.; Alvarado, A. P.; Mercerat, D.; Beck, S. L.; Leon Rios, S.; Meltzer, A.; Charvis, P.; Regnier, M. M.; Jarrin, P.; Rietbrock, A.; Vasconez, F.; Dionicio, V.; Calvache, M. L.; Singaucho, J. C.; Pazmino, A.; Rolandone, F.; Mothes, P. A.; Nocquet, J. M.; Martin, X.; Viracucha, C.; Audin, L.; Saillard, M.; Laurendeau, A.; Perrault, M.; Garth, T.; Pernoud, M.; Barros, J. G.; Yates, B.; Malengros, D.; Oregioni, D.; Villegas Lanza, J. C.; Cisneros, D.; Gomez, J.; Montes, L.; Beauval, C. M.; Bertrand, E.; Delouis, B.; Ruiz Paspuel, A. G.; Freymueller, J. T.; Williams, K.; La Femina, P.; Fuenzalida, A.; Mariniere, J.; Cheze, J.; Gueguen, P.; Maron, C.; Michaud, F.; Yepes, H. A.; Palacios, P.; Vallee, M.; Deschamps, A.; Gabriela, P.; Ambrois, D.; Ramos, C.; Courboulex, F.

2016-12-01

The Pedernales earthquake is a large Mw7.8 subduction earthquake caused by the relative convergence between the Nazca and South American plates. It occured north of the city of Pedernales, at 21 km depth and struck the coastal and densely populated Manabi Province, causing many casualties, structural damages and widespread surficial deformation. The 2016 epicenter was located near the Mw 7.8 1942 epicenter. Both events are similar in size and probably ruptured the same segment, which also corresponds to the southern part of the 1906 Mw8.8 Ecuador-Colombia megathrust rupture zone. Immediately after the earthquake, an international team from Ecuador, France, Colombia, the United Kingdom, Peru and the United States coordinated a scientific response with the respective financial support of EPN, IRD and CNRS, SGC, NERC and NSF. Equipment was provided by IGEPN, IRD, CEREMA, SGC, LIVERPOOL, IRIS PASSCAL and UNAVCO. Within a 1.5 month, the team progressively deployed a temporary seismic network of about 70 accelerometer and seismic stations, and 17 continuous GPS stations, complementing the permanent seismic, accelerometer and geodetic network of the IG-EPN. The dense network covers the 300 x 150 km wide area affected by the earthquake, including a trench-parallel line of 10 ocean bottom seismometers deployed by the R/V Orion of INOCAR for 6 months, assuring a minimized azimuthal gap. Intense seismicity is observed up to 150 km N- and S-ward from the rupture zone aligning mainly along 3 seismic strips roughly perpendicular to the trench and also near the rupture area. Peak ground and spectral accelerations are compared with existing ground-motion prediction equations (GMPEs) developed for interface earthquakes. Different soil investigations were realized to highlight soil characteristics in cities. The geodetic observations captured the immediate afterslip and will help determining the time history of afterslip and viscoelastic relaxation in response to this earthquake. A field survey was conducted on-land to describe the coseismic tectonic deformations and damages to buildings. At sea, a multibeam bathymetry survey of the margin over the rupture zone was conducted by the R/V Orion, making it possible to tentatively estimate and quantify sea-floor deformation after and before the earthquake.

Foraging Distance of the Argentine Ant in California Vineyards.

PubMed

Hogg, Brian N; Nelson, Erik H; Hagler, James R; Daane, Kent M

2018-04-02

Argentine ants, Linepithema humile (Mayr) (Hymenoptera: Formicidae), form mutualisms with hemipteran pests in crop systems. In vineyards, they feed on honeydew produced by mealybugs and soft scales, which they tend and protect from natural enemies. Few options for controlling Argentine ants are available; one of the more effective approaches is to use liquid baits containing a low dose of an insecticide. Knowledge of ant foraging patterns is required to estimate how many bait stations to deploy per unit area. To measure how far ants move liquid bait in vineyards, we placed bait stations containing sugar water and a protein marker in plots for 6 d, and then collected ants along transects extending away from bait stations. The ants moved an average of 16.08 m and 12.21 m from bait stations in the first and second years of the study, respectively. Marked ants were found up to 63 m from bait stations; however, proportions of marked ants decreased exponentially as distance from the bait station increased. Results indicate that Argentine ants generally forage at distances <36 m in California vineyards, thus suggesting that insecticide bait stations must be deployed at intervals of 36 m or less to control ants. We found no effect of insecticide on distances that ants moved the liquid bait, but this may have been because bait station densities were too low to affect the high numbers of Argentine ants that were present at the study sites.

Using Earthquake Location and Coda Attenuation Analysis to Explore Shallow Structures Above the Socorro Magma Body, New Mexico

NASA Astrophysics Data System (ADS)

Schmidt, J. P.; Bilek, S. L.; Worthington, L. L.; Schmandt, B.; Aster, R. C.

2017-12-01

The Socorro Magma Body (SMB) is a thin, sill-like intrusion with a top at 19 km depth covering approximately 3400 km2 within the Rio Grande Rift. InSAR studies show crustal uplift patterns linked to SMB inflation with deformation rates of 2.5 mm/yr in the area of maximum uplift with some peripheral subsidence. Our understanding of the emplacement history and shallow structure above the SMB is limited. We use a large seismic deployment to explore seismicity and crustal attenuation in the SMB region, focusing on the area of highest observed uplift to investigate the possible existence of fluid/magma in the upper crust. We would expect to see shallower earthquakes and/or higher attenuation if high heat flow, fluid or magma is present in the upper crust. Over 800 short period vertical component geophones situated above the northern portion of the SMB were deployed for two weeks in 2015. This data is combined with other broadband and short period seismic stations to detect and locate earthquakes as well as to estimate seismic attenuation. We use phase arrivals from the full dataset to relocate a set of 33 local/regional earthquakes recorded during the deployment. We also measure amplitude decay after the S-wave arrival to estimate coda attenuation caused by scattering of seismic waves and anelastic processes. Coda attenuation is estimated using the single backscatter method described by Aki and Chouet (1975), filtering the seismograms at 6, 9 and 12 Hz center frequencies. Earthquakes occurred at 2-13 km depth during the deployment, but no spatial patterns linked with the high uplift region were observed over this short duration. Attenuation results for this deployment suggest Q ranging in values of 130 to 2000, averaging around Q of 290, comparable to Q estimates of other studies of the western US. With our dense station coverage, we explore attenuation over smaller scales, and find higher attenuation for stations in the area of maximum uplift relative to stations outside of the maximum uplift, which could indicate upper crustal heterogeneities with shallow process above the magma body in this area.

Photograph of Apollo 17 Lunar Roving Vehicle traverses

NASA Image and Video Library

1972-10-01

S72-03145 (October 1972) --- A vertical view of the Apollo 17 Taurus-Littrow site with an overlay to illustrate the three planned Apollo 17 traverses using the Lunar Roving Vehicle (LRV). The EVA-1 traverse has a single station (1); the EVA-2 traverse has four stations (2,3,4,5); and the EVA-3 traverse has five stations (6,7,8,9,10). Stations 10-A and 10-B are alternate locations for Station 10. In addition to the major stations mentioned above, brief stops are planned for sampling between stations using the LRV sampler tool (note diamond-shaped figures), and for deploying explosive charges associated with the Lunar Seismic Profiling Experiment (LSPE - note black x-marks).

Space Station - An integrated approach to operational logistics support

NASA Technical Reports Server (NTRS)

Hosmer, G. J.

1986-01-01

Development of an efficient and cost effective operational logistics system for the Space Station will require logistics planning early in the program's design and development phase. This paper will focus on Integrated Logistics Support (ILS) Program techniques and their application to the Space Station program design, production and deployment phases to assure the development of an effective and cost efficient operational logistics system. The paper will provide the methodology and time-phased programmatic steps required to establish a Space Station ILS Program that will provide an operational logistics system based on planned Space Station program logistics support.

Fifth anniversary of the first element of the International Spac

NASA Image and Video Library

2003-12-03

In the Space Station Processing Facility (SSPF), Charles J. Precourt, deputy manager of NASA's International Space Station Program, is interviewed by a reporter from a local television station. Representatives from the media were invited to commemorate the fifth anniversary of the launch of the first element of the Station with a tour of the facility and had the opportunity to see Space Station hardware that is being processed for deployment once the Space Shuttles return to flight. NASA and Boeing mission managers were on hand to talk about the various hardware elements currently being processed for flight.

SEISMIC ANISOTROPY ANALYSIS IN THE VICTORIA LAND REGION (ANTARCTICA)

NASA Astrophysics Data System (ADS)

Salimbeni, S.; Pondrelli, S.; Danesi, S.; Morelli, A.

2009-12-01

We present here shear wave splitting results obtained from analysis of core refracted teleseismic phases in the Victoria Land region (Antarctica). We used data belonging to permanent and temporary stations in the area. The temporary stations are located around the David Glaciers and installation is part of two expeditions inside the Italian National Antarctic program (PNRA, Programma Nazionale di Ricerche in Antartide). The network was composed by 8 seismic stations, located on rocky outcrops around the glacier, and has been active from November 2003 to February 2004, and from November 2005 to February 2006. One of this (STAR) became permanent on 2004 and data until 2007 are analyzed. We use eigenvalue technique of Silver and Chan (1991) to linearize the rotated and shifted shear wave particle motions and determine the best splitting parameters. Scattered distribution of single shear-wave measurements is obtained. Null measurements follow the same distribution. Average measurements show clearly that the main anisotropy direction is NE-SW, accordingly with previous measurements obtained around this zone. Only two stations, OHG and STAR, have a different orientation and a N-S and NNW-SSE main directions are obtained respectively. The distribution of single shear-wave splitting measurements evidenced periodicity respect the back-azimuth of the events analyzed, therefore a possible two layers anisotropic structures could be supposed. To test this hypothesis we used the Menke and Levin (2003) code that allow to model waveforms using a cross convolution technique in one and two layer's cases. Significant improvements of the misfit in the double layer case allow choosing this more complex model. The one layer structure is the best for permanent stations TNV and VNDA with directions and delay time accordingly with average measurements. The double layer models fit better the data on stations STAR, located near the coast, and OHG located inland, and show in both cases the same contribution of the anisotropy.

78 FR 42010 - Drawbridge Operation Regulation; Isle of Wight (Sinepuxent) Bay, Ocean City, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-15

... Station Ocean City reveals that, in the past, vessel traffic for that time of year is very limited with... INFORMATION CONTACT: If you have questions on this temporary deviation, call or email Kashanda Booker, Bridge... . If you have questions on viewing the docket, call Barbara Hairston, Program Manager, Docket...

75 FR 30708 - Safety Zone; Red Bull Air Race, Detroit River, Detroit, MI

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-02

... each day of its effective period. Additionally, prior to the event, local sailing and yacht clubs will... local sailing and yacht clubs. In the event this temporary safety zone affects shipping, commercial... and yacht clubs will be provided with information by Coast Guard Station Belle Isle on what to expect...

50 CFR 32.43 - Mississippi.

Code of Federal Regulations, 2010 CFR

2010-10-01

... complete the reverse side of the card and deposit it at one of the hunter information stations. Include all... nontoxic shotgun shot (see § 32.2(k)) and .22 caliber rifles. We prohibit all handguns. 4. All hunters or.... You must only use portable or temporary blinds. 3. You may only possess approved nontoxic shot (see...

Trip Report United Arab Emirates

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

Nakanishi, K; Rodgers, A

2004-10-06

Keith Nakanishi and Arthur Rodgers traveled to the United Arab Emirates in February, 2004 to continue an on-going technical collaboration with UAE University and to service the two temporary LLNL seismic stations. Nakanishi and Rodgers then participated in the Gulf Seismic Forum, which was organized by LLNL and sponsored by the University of Sharjah.

The Global Seismographic Network (GSN): Deployment of Next Generation VBB Borehole Sensors and Improving Overall Network Noise Performance

NASA Astrophysics Data System (ADS)

Hafner, K.; Davis, P.; Wilson, D.; Sumy, D.

2017-12-01

The Global Seismographic Network (GSN) recently received delivery of the next generation Very Broadband (VBB) borehole sensors purchased through funding from the DOE. Deployment of these sensors will be underway during the end of summer and fall of 2017 and they will eventually replace the aging KS54000 sensors at approximately one-third of the GSN network stations. We will present the latest methods of deploying these sensors in the existing deep boreholes. To achieve lower noise performance at some sites, emplacement in shallow boreholes might result in lower noise performance for the existing site conditions. In some cases shallow borehole installations may be adapted to vault stations (which make up two thirds of the network), as a means of reducing tilt-induced signals on the horizontal components. The GSN is creating a prioritized list of equipment upgrades at selected stations with the ultimate goal of optimizing overall network data availability and noise performance. For an overview of the performance of the current GSN relative to selected set of metrics, we are utilizing data quality metrics and Probability Density Functions (PDFs)) generated by the IRIS Data Management Centers' (DMC) MUSTANG (Modular Utility for Statistical Knowledge Gathering) and LASSO (Latest Assessment of Seismic Station Observations) tools. We will present our metric analysis of GSN performance in 2016, and show the improvements at GSN sites resulting from recent instrumentation and infrastructure upgrades.

CentNet—A deployable 100-station network for surface exchange research

NASA Astrophysics Data System (ADS)

Oncley, S.; Horst, T. W.; Semmer, S.; Militzer, J.; Maclean, G.; Knudson, K.

2014-12-01

Climate, air quality, atmospheric composition, surface hydrology, and ecological processes are directly affected by the Earth's surface. Complexity of this surface exists at multiple spatial scales, which complicates the understanding of these processes. NCAR/EOL currently provides a facility to the research community to make direct eddy-covariance flux observations to quantify surface-atmosphere interactions. However, just as model resolution has continued to increase, there is a need to increase the spatial density of flux measurements to capture the wide variety of scales that contribute to exchange processes close to the surface. NCAR/EOL now has developed the CentNet facility, that is envisioned to have on the order of 100 surface flux stations deployable for periods of months to years. Each station would measure standard meteorological variables, all components of the surface energy balance (including turbulence fluxes and radiation), atmospheric composition, and other quantities to characterize the surface. Thus, CentNet can support observational research in the biogeosciences, hydrology, urban meteorology, basic meteorology, and turbulence. CentNet has been designed to be adaptable to a wide variety of research problems while keeping operations manageable. Tower infrastructure has been designed to be lightweight, easily deployed, and with a minimal set-up footprint. CentNet uses sensor networks to increase spatial sampling at each station. The data system saves every sample on site to retain flexibility in data analysis. We welcome guidance on development and funding priorities as we build CentNet.

Analysis of the Seismicity Associated to the Subduction of the Rivera Plate using OBS and Onland Stations.

NASA Astrophysics Data System (ADS)

Nuñez-Cornu, F. J.; Barba, D. C., Sr.; Danobeitia, J.; Bandy, W. L.; Zamora-Camacho, A.; Marquez-Ramirez, V. H.; Ambros, M.; Gomez, A.; Sandoval, J. M.; Mortera-Gutierrez, C. A.

2016-12-01

The second stage of TsuJal Project includes the study of passive seismic activity in the region of the plate Rivera and Jalisco block by anchoring OBS and densifying the network of seismic stations on land for at least four months. This stage began in April 2016 with the deployment of 25 Obsidian stations with sensor Le-3D MkIII from the northern part of Nayarit state to the south of Colima state, including the Marias Islands. This temporal seismic network complements the Jalisco Seismic Network (RESAJ) for a total of 50 stations. Offshore, ten OBS type LCHEAPO 2000 with 4 channel (3 seismic short period and 1 pressure) were deployed, in the period from 19 to 30 April 2016 using the BO El Puma from UNAM. The OBS were deployed in an array from the Marias Islands to offcoast of the border of Colima and Michoacan states. On May 4, an earthquake with Ml = 4.2 took place in the contact area of the Rivera Plate, Cocos Plate and the Middle America Trench, subsequently occurred a seismic swarm with over 200 earthquakes until May 16, including an earthquake with Ml = 5.0 on May 7. A second swarm took place between May 28 and Jun 4 including an earthquake with Ml = 4.8 on Jun 1. An analysis of the quality of different location methods is presented: automatic preliminary RESAJ location using Antelope; location with revised RESAJ phases in Antelope; relocation of RESAJ data with hypo and a regional velocity model; relocation of RESAJ data with hypo adding data from the temporal seismic network stations; and finally the relocation adding the data from the OBS network. Moreover, the tectonic implications of these earthquakes are discussed.

Lively Earthquake Activity in North-Eastern Greenland

NASA Astrophysics Data System (ADS)

Larsen, Tine B.; Dahl-Jensen, Trine; Voss, Peter H.

2016-04-01

The seismograph at the Danish military outpost, Station Nord (NOR) in North East Greenland, records many regional/local earthquakes every day. Most of these events originate at the Arctic plate boundary between the Eurasian and the North American plates. The plate boundary has a particularly active segment approximately 200 km from the seismograph. Additionally we find a seismically very active region 20-30 km from NOR on the Kronprins Christian Land peninsula. The BB seismograph at NOR was installed in 2002 and later upgraded with real-time telemetry as part of the GLISN-project. Since late 2013 data from NOR have been included in routine processing at GEUS. Phase readings on some of the older data, primarily 2002-2003, have been carried out previously in connection with other projects. As a result, phase readings for more than 6000 local events, recorded exclusively at NOR, were found in the GEUS data base. During the years 2004 to 2007 four locations were occupied by temporary BB seismographs on the North coast of Greenland as part of the Law of the Sea preparatory work. Data from these stations have not previously been analyzed for local and regional events. In this study we combine the recordings from NOR with phase readings from the temporary seismographs in Northern Greenland. The local events on Kronprins Christian Land range in magnitude from less than 2 to a 4.8 event widely recorded in the region and felt by the personnel at Station Nord on August 30, 2005. Station Nord is located in the seismically most active region of Greenland.

Development of a Comprehensive Blast-Related Auditory Injury Database (BRAID)

DTIC Science & Technology

2016-05-01

these, may result in temporary or persistent noise-induced hear- ing loss (NIHL) and tinnitus . NIHL and tinnitus present a problematic public...uals deployed to battle zones are increasingly at risk for NIHL, tinnitus , and other otologic injuries [4]. The effects of blast exposure on the...primary interest because it may be permanent and cause persistent symptoms of tinnitus [18–20] and hear- ing loss [6,17,21–23]. Blast-related middle

Logistics Handbook for Strategic Mobility Planning

DTIC Science & Technology

1994-04-01

tion 83 E. Flatrack Characteristics 85 F. Seashed Characteristics 88 G. Equipment Deployment and Storage Systems (EDSS) 88 H. Palletized Load...Equipment Deployment and Storage Systems (EDSS) 94 41 Containerizable Unit Equipment 97 42 Mobilization Station to Inland Waterway Dock Mileage 101...passengers worldwide, and the DOD Worldwide Personal Property Movement and Storage Program. 15 MTMC also provides interface between military shippers

Different adaptations of Chinese winter-over expeditioners during prolonged Antarctic and sub-Antarctic residence.

PubMed

Chen, Nan; Wu, Quan; Li, Hao; Zhang, Tao; Xu, Chengli

2016-05-01

Prolonged residence in Antarctica is characterized by exposure to isolated, confined, and extreme (ICE) environment. Winter-over expeditioners at research stations often exhibit a complex of psychophysiological symptoms, which varied by stations and sociocultural backgrounds. To understand the different patterns of psychophysiological responses provoked by environmental stress, we conducted a longitudinal assessment of mood and endocrine function in two groups of Chinese expeditioners who were deployed to sub-Antarctic (Great Wall Station, 62°S, N = 12) and Antarctic (Zhongshan Station, 66°S, N = 16) from December 2003 to 2005. Measures of mood, thyroid function, the levels of plasma catecholamine, and circulating interleukins were obtained at departure from China, mid-winter (Antarctica), end of winter (Antarctica), and return to China, respectively. The Zhongshan Station crew experienced significant increases in fatigue, anger, tension, confusion, and decrease in free thyroxine (FT4), norepinephrine (NE), and epinephrine (E) during the winter, increase in thyrotropin (TSH) and total triiodothyronine (TT3) when returning, whereas their counterparts at Great Wall Station only experienced increased TT3 after deployment. Moreover, compared with the Great Wall Station crew, the Zhongshan Station crew exhibited greater increase in anger, greater decrease in FT4, total thyroxine (TT4), NE and E over the winter, and greater increase in TSH when returning. Chinese expeditioners who lived and worked at the Antarctic station and the sub-Antarctic station for over a year showed different change patterns in mood and endocrine hormones. Negative mood and endocrine dysfunction were positively associated with the severity of environment. The study is a supplement to scientific knowledge on psychophysiological variation under ICE environment, which has certain applied value for the development of preventive countermeasures or interventions.

Different adaptations of Chinese winter-over expeditioners during prolonged Antarctic and sub-Antarctic residence

NASA Astrophysics Data System (ADS)

Chen, Nan; Wu, Quan; Li, Hao; Zhang, Tao; Xu, Chengli

2016-05-01

Prolonged residence in Antarctica is characterized by exposure to isolated, confined, and extreme (ICE) environment. Winter-over expeditioners at research stations often exhibit a complex of psychophysiological symptoms, which varied by stations and sociocultural backgrounds. To understand the different patterns of psychophysiological responses provoked by environmental stress, we conducted a longitudinal assessment of mood and endocrine function in two groups of Chinese expeditioners who were deployed to sub-Antarctic (Great Wall Station, 62°S, N = 12) and Antarctic (Zhongshan Station, 66°S, N = 16) from December 2003 to 2005. Measures of mood, thyroid function, the levels of plasma catecholamine, and circulating interleukins were obtained at departure from China, mid-winter (Antarctica), end of winter (Antarctica), and return to China, respectively. The Zhongshan Station crew experienced significant increases in fatigue, anger, tension, confusion, and decrease in free thyroxine (FT4), norepinephrine (NE), and epinephrine (E) during the winter, increase in thyrotropin (TSH) and total triiodothyronine (TT3) when returning, whereas their counterparts at Great Wall Station only experienced increased TT3 after deployment. Moreover, compared with the Great Wall Station crew, the Zhongshan Station crew exhibited greater increase in anger, greater decrease in FT4, total thyroxine (TT4), NE and E over the winter, and greater increase in TSH when returning. Chinese expeditioners who lived and worked at the Antarctic station and the sub-Antarctic station for over a year showed different change patterns in mood and endocrine hormones. Negative mood and endocrine dysfunction were positively associated with the severity of environment. The study is a supplement to scientific knowledge on psychophysiological variation under ICE environment, which has certain applied value for the development of preventive countermeasures or interventions.

Global Precipitation Measurement (GPM) and International Space Station (ISS) Coordination for CubeSat Deployments to Minimize Collision Risk

NASA Technical Reports Server (NTRS)

Pawloski, James H.; Aviles, Jorge; Myers, Ralph; Parris, Joshua; Corley, Bryan; Hehn, Garrett; Pascucci, Joseph

2016-01-01

The Global Precipitation Measurement Mission (GPM) is a joint U.S. and Japan mission to observe global precipitation, extending the Tropical Rainfall Measuring Mission (TRMM), which was launched by H-IIA from Tanegashima in Japan on February 28TH, 2014 directly into its 407km operational orbit. The International Space Station (ISS) is an international human research facility operated jointly by Russia and the USA from NASA's Johnson Space Center (JSC) in Houston Texas. Mission priorities lowered the operating altitude of ISS from 415km to 400km in early 2105, effectively placing both vehicles into the same orbital regime. The ISS has begun a program of deployments of cost effective CubeSats from the ISS that allow testing and validation of new technologies. With a major new asset flying at the same effective altitude as the ISS, CubeSat deployments became a serious threat to GPM and therefore a significant indirect threat to the ISS. This paper describes the specific problem of collision threat to GPM and risk to ISS CubeSat deployment and the process that was implemented to keep both missions safe from collision and maximize their project goals.

View of the new CMG during Expedition 15/STS-118 EVA 2

NASA Image and Video Library

2007-08-13

ISS015-E-22366 (13 Aug. 2007) --- A close-up view of the new control moment gyroscope (CMG) photographed by a crewmember during the mission's second planned session of extravehicular activity (EVA). During the spacewalk, Canadian Space Agency's astronaut Dave Williams (out of frame) and astronaut Rick Mastracchio (out of frame), both STS-118 mission specialists, removed a faulty control moment gyroscope (CMG-3) and installed a new CMG into the station's Z1 truss. The failed CMG will remain at its temporary stowage location on the station's exterior before it is returned to Earth on a later shuttle mission. The new gyroscope is one of four CMGs that are used to control the station's attitude in orbit.

Brown at aft controls during PAMS STU deploy

NASA Image and Video Library

1996-05-22

S77-E-5066 (22 May 1996) --- Astronaut Curtis L. Brown, Jr., pilot, is seen on the starboard side of the Space Shuttle Endeavour's aft flight deck just prior to the deployment of the Satellite Test Unit (STU), part of the Passive Aerodynamically Stabilized Magnetically Damped Satellite (PAMS). Brown's image was captured with an Electronic Still Camera (ESC). Minutes later the camera was being used to document the deployment of PAMS-STU. The six-member crew will continue operations (tracking, rendezvousing and station-keeping) with PAMS-STU periodically throughout the remainder of the mission.

Using a new device to prevent pulmonary embolisms during pharmacomechanical thrombectomy.

PubMed

Calleja, E; Ciampi, J J; Puche, J J; Lanciego, C

2018-04-20

We have used a new device to prevent pulmonary embolism during pharmacomechanical thrombectomy in a 25-year-old postpartum woman. The Angel® catheter (BiO2 Medical Inc., Golden, CO, USA) is a temporary device that combines the functions of a vena cava filter (VCF) with those of a triple-lumen central venous catheter. Normally, a VCF is implanted to prevent pulmonary embolism during pharmacomechanical thrombectomy. However, the complications associated with VCFs increase with time, not all of the filter can always be retrieved, and there can be iatrogenic effects both during implantation and retrieval. In our experience, this new device is much simpler to deploy and to retrieve. As is shown in this case, this temporary device can be an interesting alternative to a VCF for preventing pulmonary embolisms during pharmacomechanical thrombectomy. Copyright © 2018 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Analytical investigation of the dynamics of tethered constellations in Earth orbit, phase 2

NASA Technical Reports Server (NTRS)

Lorenzini, Enrico C.; Gullahorn, Gordon E.; Cosmo, Mario L.; Estes, Robert D.; Grossi, Mario D.

1994-01-01

This final report covers nine years of research on future tether applications and on the actual flights of the Small Expendable Deployment System (SEDS). Topics covered include: (1) a description of numerical codes used to simulate the orbital and attitude dynamics of tethered systems during station keeping and deployment maneuvers; (2) a comparison of various tethered system simulators; (3) dynamics analysis, conceptual design, potential applications and propagation of disturbances and isolation from noise of a variable gravity/microgravity laboratory tethered to the Space Station; (4) stability of a tethered space centrifuge; (5) various proposed two-dimensional tethered structures for low Earth orbit for use as planar array antennas; (6) tethered high gain antennas; (7) numerical calculation of the electromagnetic wave field on the Earth's surface on an electrodynamically tethered satellite; (8) reentry of tethered capsules; (9) deployment dynamics of SEDS-1; (10) analysis of SEDS-1 flight data; and (11) dynamics and control of SEDS-2.

Sao Paulo Lightning Mapping Array (SP-LMA): Deployment and Plans

NASA Technical Reports Server (NTRS)

Bailey, J. C.; Carey, L. D.; Blakeslee, R. J.; Albrecht, R.; Morales, C. A.; Pinto, O., Jr.

2011-01-01

An 8-10 station Lightning Mapping Array (LMA) network is being deployed in the vicinity of Sao Paulo to create the SP-LMA for total lightning measurements in association with the international CHUVA [Cloud processes of tHe main precipitation systems in Brazil: A contribUtion to cloud resolVing modeling and to the GPM (GlobAl Precipitation Measurement)] field campaign. Besides supporting CHUVA science/mission objectives and the Sao Luz Paraitinga intensive operation period (IOP) in December 2011-January 2012, the SP-LMA will support the generation of unique proxy data for the Geostationary Lightning Mapper (GLM) and Advanced Baseline Imager (ABI), both sensors on the NOAA Geostationary Operational Environmental Satellite-R (GOES-R), presently under development and scheduled for a 2015 launch. The proxy data will be used to develop and validate operational algorithms so that they will be ready for use on "day1" following the launch of GOES-R. A preliminary survey of potential sites in the vicinity of Sao Paulo was conducted in December 2009 and January 2010, followed up by a detailed survey in July 2010, with initial network deployment scheduled for October 2010. However, due to a delay in the Sa Luz Paraitinga IOP, the SP-LMA will now be installed in July 2011 and operated for one year. Spacing between stations is on the order of 15-30 km, with the network "diameter" being on the order of 30-40 km, which provides good 3-D lightning mapping 150 km from the network center. Optionally, 1-3 additional stations may be deployed in the vicinity of Sa Jos dos Campos.

Sao Paulo Lightning Mapping Array (SP-LMA): Deployment, Operation and Initial Data Analysis

NASA Technical Reports Server (NTRS)

Blakeslee, R.; Bailey, J. C.; Carey, L. D.; Rudlosky, S.; Goodman, S. J.; Albrecht, R.; Morales, C. A.; Anseimo, E. M.; Pinto, O.

2012-01-01

An 8-10 station Lightning Mapping Array (LMA) network is being deployed in the vicinity of Sao Paulo to create the SP-LMA for total lightning measurements in association with the international CHUVA [Cloud processes of the main precipitation systems in Brazil: A contribution to cloud resolving modeling and to the GPM (Global Precipitation Measurement)] field campaign. Besides supporting CHUVA science/mission objectives and the Sao Luiz do Paraitinga intensive operation period (IOP) in November-December 2011, the SP-LMA will support the generation of unique proxy data for the Geostationary Lightning Mapper (GLM) and Advanced Baseline Imager (ABI), both sensors on the NOAA Geostationary Operational Environmental Satellite-R (GOES-R), presently under development and scheduled for a 2015 launch. The proxy data will be used to develop and validate operational algorithms so that they will be ready for use on "day1" following the launch of GOES-R. A preliminary survey of potential sites in the vicinity of Sao Paulo was conducted in December 2009 and January 2010, followed up by a detailed survey in July 2010, with initial network deployment scheduled for October 2010. However, due to a delay in the Sao Luiz do Paraitinga IOP, the SP-LMA will now be installed in July 2011 and operated for one year. Spacing between stations is on the order of 15-30 km, with the network "diameter" being on the order of 30-40 km, which provides good 3-D lightning mapping 150 km from the network center. Optionally, 1-3 additional stations may be deployed in the vicinity of Sao Jos dos Campos.

PC-based automation system streamlines operations

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

Bowman, J.

1995-10-01

The continued emergence of PC-based automation systems in the modern compressor station is driving the need for personnel who have the special skills need to support them. However, the dilemma is that operating budget restraints limit the overall number of people available to operate and maintain compressor stations. An ideal solution is to deploy automation systems which can be easily understood and supported by existing compressor station personnel. This paper reviews such a system developed by Waukesha-Pearce Industries, Inc.

STS-49 crew in JSC's FB Shuttle Mission Simulator (SMS) during simulation

NASA Image and Video Library

1992-02-19

S92-29406 (Feb 1992) --- Three mission specialists assigned to the STS-49 flight occupy temporary stations on the "middeck" of a Johnson Space Center (JSC) Shuttle trainer during a rehearsal of Endeavour's launch and entry phases. Left to right are astronauts Thomas D. Akers, Kathryn C. Thornton and Pierre J. Thuot. The three, along with four other NASA astronauts, will be aboard Endeavour in May for a week-long mission during which a satellite will be retrieved and boosted toward a higher orbit and extravehicular activity evaluations for Space Station Freedom assembly techniques will be conducted.

KSC-07pd2026

NASA Image and Video Library

2007-07-19

KENNEDY SPACE CENTER, Fla. -- In the Orbiter Processing Facility bay 3, workers are ready to move a main bus switching unit into Discovery's payload bay. A main bus switching unit is used for power distribution, circuit protection and fault isolation on the space station's power system. The units route power to proper locations in the space station, such as from solar arrays through umbilicals into the U.S. Lab. The unit will be installed on the external stowage platform 2 attached to the Quest airlock for temporary storage. Discovery is targeted to launch mission STS-120 no earlier than Oct. 20. Photo credit: NASA/Jim Grossmann

KSC-07pd2028

NASA Image and Video Library

2007-07-19

KENNEDY SPACE CENTER, Fla. -- In the Orbiter Processing Facility bay 3, workers check the placement of a main bus switching unit in Discovery's payload bay. A main bus switching unit is used for power distribution, circuit protection and fault isolation on the space station's power system. The units route power to proper locations in the space station, such as from solar arrays through umbilicals into the U.S. Lab. The unit will be installed on the external stowage platform 2 attached to the Quest airlock for temporary storage. Discovery is targeted to launch mission STS-120 no earlier than Oct. 20. Photo credit: NASA/Jim Grossmann

KSC-04PD-2309

NASA Technical Reports Server (NTRS)

2004-01-01

KENNEDY SPACE CENTER, FLA. In the Space Station Processing Facility, workers watch the progress of the Multi-Purpose Logistics Module Leonardo as it moves across the building to the Cargo Element Work Stand that Raffaello recently vacated. The payload canister was a temporary location during the switch. At right is the MPLM Raffaello, temporarily occupying the Element Rotation Stand formerly holding Leonardo. Three MPLMs were built by the Italian Space Agency Donatello, Leonardo and Raffaello to serve as a reusable logistics carrier and primary delivery system to resupply and return cargo requiring a pressurized environment to the International Space Station.

International seismological data center: Preparation of an experimental data base

NASA Astrophysics Data System (ADS)

Israelson, H.; Jeppsson, I.; Barkeby, G.

1980-11-01

An experimental data base compiled for a temporary international seismological data center is presented. Data include recording and measurements at 60 globally distributed seismological stations for a one week period. Data for definition, location and magnitude estimation of seismic events are examined. Original digital records from 11 seismological research observatories around the world are also analyzed to provide additional identification data. It is shown that the routine measurement and reporting of data at seismological stations as proposed by the Seismic Experts Group at the UN Committee of Disarmament, is an onerous task that goes far beyond current seismological practices.

Forest research notes, Pacific Northwest Forest Experiment Station, No. 31, November 30, 1940.

Treesearch

P.A. Briegleb; Theodore Kachin; L.A. Isaac; Fremont McComb; T.T. Munger

1940-01-01

The pulp and paper industry in the Pacific Northwest is able to compete successfully in national and world markets primarily bemuse it is favored with dense stands of high-grade pulpwood in its back yard. This natural advantage need not be temporary. Here industry can obtain such stands continuously because it can grow them.

75 FR 53985 - Arizona Public Service Company, et al., Palo Verde Nuclear Generating Station, Unit 3; Temporary...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

... are authorized by law, will not present an undue risk to public health or safety, and are consistent... Public Health and Safety The underlying purpose of 10 CFR 50.46 is to establish acceptance criteria for... (LOCA) and non-LOCA criteria, mechanical design, thermal hydraulics, seismic, core physics, and...

Photocopy of drawing (this photograph is an 8" x 10" ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of drawing (this photograph is an 8" x 10" copy of an 8" x 10" negative; 1871 original architectural drawing located at Building No. 458, NAS Pensacola, Florida) Temporary Officers Quarters Ground plans of kitchens to officers quarters - U.S. Naval Air Station, Senior Officers' Quarters Q-3, Q-3 North Avenue, Pensacola, Escambia County, FL

41 CFR 302-3.404 - Under what circumstances will my agency authorize a TCS?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false Under what circumstances will my agency authorize a TCS? 302-3.404 Section 302-3.404 Public Contracts and Property Management... SPECIFIC TYPE Employee's Temporary Change Of Station § 302-3.404 Under what circumstances will my agency...

Use of Scented Sugar Bait Stations to Track Mosquito-Borne Arbovirus Transmission in California

PubMed Central

LOTHROP, HUGH D.; WHEELER, SARAH S.; FANG, YING; REISEN, WILLIAM K.

2012-01-01

Laboratory and field research was conducted to determine if Culex tarsalis Coquillett expectorated West Nile virus (WNV) during sugar feeding and if a lure or bait station could be developed to exploit this behavior for WNV surveillance. Experimentally infected Cx. tarsalis repeatedly expectorated WNV onto filter paper strips and into vials with wicks containing sucrose that was readily detectable by a quantitative reverse transcriptase-polymerase chain reaction assay. Few females (33%, n = 27) became infected by imbibing sugar solutions spiked with high concentrations (107 plaque forming units/ml) of WNV, indicating sugar feeding stations probably would not be a source of WNV infection. In nature, sugar bait stations scented with the floral attractant phenyl acetaldehyde tracked WNV transmission activity in desert but not urban or agricultural landscapes in California. When deployed in areas of the Coachella Valley with WNV activity during the summer of 2011, 27 of 400 weekly sugar samples (6.8%) tested positive for WNV RNA by reverse transcriptase-polymerase chain reaction. Prevalence of positives varied spatially, but positive sugar stations were detected before concurrent surveillance measures of infection (mosquito pools) or transmission (sentinel chicken seroconversions). In contrast, sugar bait stations deployed in urban settings in Los Angeles or agricultural habits near Bakersfield in Kern County supporting WNV activity produced 1 of 90 and 0 of 60 positive weekly sugar samples, respectively. These results with sugar bait stations will require additional research to enhance bait attractancy and to understand the relationship between positive sugar stations and standard metrics of arbovirus surveillance. PMID:23270177

Deployed P4 Radiator during STS-115 EVA during Joint Operations

NASA Image and Video Library

2006-09-15

S115-E-06143 (15 Sept. 2006) --- Backdropped by a blue and white Earth, the newly installed P3/P4 truss and the Canadarm2 of the International Space Station are featured in this image photographed by a STS-115 crewmember while the Space Shuttle Atlantis was docked with the International Space Station.

Seismological characteristics of the 2011 unrest in Santorini caldera: Implications for observed deformation and volcano-tectonics

NASA Astrophysics Data System (ADS)

Konstantinou, Konstantinos; Evangelidis, Christos; Melis, Nikolaos; Liang, Wen-Tzong

2013-04-01

Santorini caldera has experienced several explosive eruptions in the past, the most well-known of these being the Late Bronze Age (ca. 1628 BC) eruption that may have been responsible for the demise of the Minoan civilization. Since the early 1950's the volcano has been dormant without exhibiting any significant activity except from discharge of low-temperature hydrothermal fluids. In January 2011 both deformation and seismic activity increased considerably signaling a period of unrest which however, did not result in an eruption. One permanent and seven temporary seismic stations equipped with three-component sensors were deployed by the National Observatory of Athens. These were combined with seismic stations from the University of Thessaloniki, seven with only a vertical component and four with three-component sensors and all operated under the Hellenic Unified Seismic Network, thus densely monitoring the Santorini Volcano. These seismic stations have recorded the seismic activity from its start up to now. About 290 micro-earthquakes recorded by at least 5 stations were analyzed for the purpose of obtaining accurate epicentral and hypocentral locations using both catalog and differential travel times from waveform cross-correlation. All of these events exhibit clear P- and S-phases indicating that they resulted from shear failure of rock rather than fluid-flow within volcanic conduits. Results show two well-defined clusters in Palea and Nea Kameni islands within the caldera with hypocentral depths ranging between 5-10 km. Interestingly, one more cluster of events with depths between 15-19 km appears near the area of Cape Coloumbo and developed almost simultaneously with the clusters within the caldera. The Mogi source depth inferred from geodetic observations previously is shallower (~4 km) and does not coincide spatially with the clusters within the caldera. This points to the possibility that seismicity and deformation may be excited by deeper pressure changes. Shear wave splitting measurements have also been performed using all available waveform data in order to understand the nature and spatial variation of the stress field during the unrest. Fast polarization directions exhibit some orientations consistent with the regional NW-SE extension in the area, but also orientations along NE-SW that signify the presence of a local stress field as well.

Using a discrete-event simulation to balance ambulance availability and demand in static deployment systems.

PubMed

Wu, Ching-Han; Hwang, Kevin P

2009-12-01

To improve ambulance response time, matching ambulance availability with the emergency demand is crucial. To maintain the standard of 90% of response times within 9 minutes, the authors introduce a discrete-event simulation method to estimate the threshold for expanding the ambulance fleet when demand increases and to find the optimal dispatching strategies when provisional events create temporary decreases in ambulance availability. The simulation model was developed with information from the literature. Although the development was theoretical, the model was validated on the emergency medical services (EMS) system of Tainan City. The data are divided: one part is for model development, and the other for validation. For increasing demand, the effect was modeled on response time when call arrival rates increased. For temporary availability decreases, the authors simulated all possible alternatives of ambulance deployment in accordance with the number of out-of-routine-duty ambulances and the durations of three types of mass gatherings: marathon races (06:00-10:00 hr), rock concerts (18:00-22:00 hr), and New Year's Eve parties (20:00-01:00 hr). Statistical analysis confirmed that the model reasonably represented the actual Tainan EMS system. The response-time standard could not be reached when the incremental ratio of call arrivals exceeded 56%, which is the threshold for the Tainan EMS system to expand its ambulance fleet. When provisional events created temporary availability decreases, the Tainan EMS system could spare at most two ambulances from the standard configuration, except between 20:00 and 01:00, when it could spare three. The model also demonstrated that the current Tainan EMS has two excess ambulances that could be dropped. The authors suggest dispatching strategies to minimize the response times in routine daily emergencies. Strategies of capacity management based on this model improved response times. The more ambulances that are out of routine duty, the better the performance of the optimal strategies that are based on this model.

A novel approach to analysing the regimes of temporary streams in relation to their controls on the composition and structure of aquatic biota

NASA Astrophysics Data System (ADS)

Gallart, F.; Prat, N.; García-Roger, E. M.; Latron, J.; Rieradevall, M.; Llorens, P.; Barberá, G. G.; Brito, D.; De Girolamo, A. M.; Lo Porto, A.; Buffagni, A.; Erba, S.; Neves, R.; Nikolaidis, N. P.; Perrin, J. L.; Querner, E. P.; Quiñonero, J. M.; Tournoud, M. G.; Tzoraki, O.; Skoulikidis, N.; Gómez, R.; Sánchez-Montoya, M. M.; Froebrich, J.

2012-09-01

Temporary streams are those water courses that undergo the recurrent cessation of flow or the complete drying of their channel. The structure and composition of biological communities in temporary stream reaches are strongly dependent on the temporal changes of the aquatic habitats determined by the hydrological conditions. Therefore, the structural and functional characteristics of aquatic fauna to assess the ecological quality of a temporary stream reach cannot be used without taking into account the controls imposed by the hydrological regime. This paper develops methods for analysing temporary streams' aquatic regimes, based on the definition of six aquatic states that summarize the transient sets of mesohabitats occurring on a given reach at a particular moment, depending on the hydrological conditions: Hyperrheic, Eurheic, Oligorheic, Arheic, Hyporheic and Edaphic. When the hydrological conditions lead to a change in the aquatic state, the structure and composition of the aquatic community changes according to the new set of available habitats. We used the water discharge records from gauging stations or simulations with rainfall-runoff models to infer the temporal patterns of occurrence of these states in the Aquatic States Frequency Graph we developed. The visual analysis of this graph is complemented by the development of two metrics which describe the permanence of flow and the seasonal predictability of zero flow periods. Finally, a classification of temporary streams in four aquatic regimes in terms of their influence over the development of aquatic life is updated from the existing classifications, with stream aquatic regimes defined as Permanent, Temporary-pools, Temporary-dry and Episodic. While aquatic regimes describe the long-term overall variability of the hydrological conditions of the river section and have been used for many years by hydrologists and ecologists, aquatic states describe the availability of mesohabitats in given periods that determine the presence of different biotic assemblages. This novel concept links hydrological and ecological conditions in a unique way. All these methods were implemented with data from eight temporary streams around the Mediterranean within the MIRAGE project. Their application was a precondition to assessing the ecological quality of these streams.

Imaging subsurface hydrothermal structure using a dense geophone array in Yellowstone

NASA Astrophysics Data System (ADS)

Wu, S. M.; Lin, F. C.; Farrell, J.; Smith, R. B.

2016-12-01

The recent development of ambient noise cross-correlation and the availability of large N seismic arrays allow for the study of detailed shallow crustal structure. In this study, we apply multi-component noise cross-correlation to explore shallow hydrothermal structure near Old Faithful geyser in Yellowstone National Park using a temporary geophone array. The array was composed of 133 three-component 5-Hz geophones and was deployed for two weeks during November 2015. The average station spacing is 50 meters and the full aperture of the array is around 1 km with good azimuthal and spatial coverage. The Upper Geyser Basin, where Old Faithful is located, has the largest concentration of geysers in the world. This unique active hydrothermal environment and hence the extremely inhomogeneous noise source distribution makes the construction of empirical Green's functions difficult based on the traditional noise cross-correlation method. In this presentation, we show examples of the constructed cross-correlation functions and demonstrate their spatial and temporal relationships with known hydrothermal activity. We also demonstrate how useful seismic signals can be extracted from these cross-correlation functions and used for subsurface imaging. In particular, we will discuss the existence of a recharge cavity beneath Old Faithful revealed by the noise cross-correlations. In addition, we also investigated the temporal structure variation based on time-lapse noise cross-correlations and these preliminary results will also be discussed.

Deciphering the role of fluids in early stage rifting from full moment tensor inversion of East African earthquakes

NASA Astrophysics Data System (ADS)

Oliva, S. J. C.; Ebinger, C. J.; Keir, D.; Shillington, D. J.; Chindandali, P. R. N.

2016-12-01

The East African Rift splits around the Archaean Tanzania craton into the magmatic Eastern branch and the mostly amagmatic Western branch, which continues south of the craton. Temporary seismic networks recently deployed in three rift sectors allow for comparison and insights into the early stages of rifting, including areas with lower crustal earthquakes. We analyze earthquakes with ML > 3.5 in the area recorded by CRAFTI (northern Tanzania/Kenya), TANGA (Tanganyika rift), and/or SEGMeNT (Malawi rift) networks. For events not well enclosed by these arrays, nearby permanent stations are used to improve azimuthal coverage when possible. We present source mechanisms as well as better-constrained source depth estimates from moment tensor inversion using Dreger and Ford TDMT algorithm (Dreger, 2003; Minson & Dreger, 2008). Data and synthetic waveforms are bandpass filtered between 0.02 to 0.10 Hz, or a narrower frequency band within this range, depending on lake noise, which can interfere strongly on the lower end of this frequency range. Results suggest local stress reorientations as well as significant dilatation components on some events within magmatic rift sectors. The implications of these results for crustal rheology and magmatic modification will be discussed in light of the growing complementary data sets from the three projects to inform our understanding of early rifting as a whole.

Contrasts in lithospheric structure within the Australian craton—insights from surface wave tomography

NASA Astrophysics Data System (ADS)

Fishwick, S.; Kennett, B. L. N.; Reading, A. M.

2005-03-01

Contrasts in the seismic structure of the lithosphere within and between elements of the Australian Craton are imaged using surface wave tomography. New data from the WACRATON and TIGGER experiments are integrated with re-processed data from previous temporary deployments of broad-band seismometers and permanent seismic stations. The much improved path coverage in critical regions allows an interpretation of structures in the west of Australia, and a detailed comparison between different cratonic regions. Improvements to the waveform inversion procedure and a new multi-scale tomographic method increase the reliability of the tomographic images. In the shallowest part of the model (75 km) a region of lowered velocity is imaged beneath central Australia, and confirmed by the delayed arrival times of body waves for short paths. Within the cratonic lithosphere there is clearly structure at scale lengths of a few hundred kilometres; resolution tests indicate that path coverage within the continent is sufficient to reveal features of this size in the upper part of our model. In Western Australia, differences are seen beneath and within the Archaean cratons: at depths greater than 150 km faster velocities are imaged beneath the Yilgarn Craton than beneath the Pilbara Craton. In the complex North Australian Craton a fast wavespeed anomaly continuing to at least 250 km is observed below parts of the craton, suggesting the possibility of Archaean lithosphere underlying areas of dominantly Proterozoic surface geology.

Recent Seismicity in Texas and Research Design and Progress of the TexNet-CISR Collaboration

NASA Astrophysics Data System (ADS)

Hennings, P.; Savvaidis, A.; Rathje, E.; Olson, J. E.; DeShon, H. R.; Datta-Gupta, A.; Eichhubl, P.; Nicot, J. P.; Kahlor, L. A.

2017-12-01

The recent increase in the rate of seismicity in Texas has prompted the establishment of an interdisciplinary, interinstitutional collaboration led by the Texas Bureau of Economic Geology which includes the TexNet Seismic Monitoring and Research project as funded by The State of Texas (roughly 2/3rds of our funding) and the industry-funded Center for Integrated Seismicity Research (CISR) (1/3 of funding). TexNet is monitoring and cataloging seismicity across Texas using a new backbone seismic network, investigating site-specific earthquake sequences by deploying temporary seismic monitoring stations, and conducting reservoir modeling studies. CISR expands TexNet research into the interdisciplinary realm to more thoroughly study the factors that contribute to seismicity, characterize the associated hazard and risk, develop strategies for mitigation and management, and develop methods of effective communication for all stakeholders. The TexNet-CISR research portfolio has 6 themes: seismicity monitoring, seismology, geologic and hydrologic description, geomechanics and reservoir modeling, seismic hazard and risk assessment, and seismic risk social science. Twenty+ specific research projects span and connect these themes. We will provide a synopsis of research progress including recent seismicity trends in Texas; Fort Worth Basin integrated studies including geological modeling and fault characterization, fluid injection data syntheses, and reservoir and geomechanical modeling; regional ground shaking characterization and mapping, infrastructure vulnerability assessment; and social science topics of public perception and information seeking behavior.

Craton Heterogeneity in the South American Lithosphere

NASA Astrophysics Data System (ADS)

Lloyd, S.; Van der Lee, S.; Assumpcao, M.; Feng, M.; Franca, G. S.

2012-04-01

We investigate structure of the lithosphere beneath South America using receiver functions, surface wave dispersion analysis, and seismic tomography. The data used include recordings from 20 temporary broadband seismic stations deployed across eastern Brazil (BLSP02) and from the Chile Ridge Subduction Project seismic array in southern Chile (CRSP). By jointly inverting Moho point constraints, Rayleigh wave group velocities, and regional S and Rayleigh wave forms we obtain a continuous map of Moho depth. The new tomographic Moho map suggests that Moho depth and Moho relief vary slightly with age within the Precambrian crust. Whether or not a correlation between crustal thickness and geologic age can be derived from the pre-interpolation point constraints depends strongly on the selected subset of receiver functions. This implies that using only pre-interpolation point constraints (receiver functions) inadequately samples the spatial variation in geologic age. We also invert for S velocity structure and estimate the depth of the lithosphere-asthenosphere boundary (LAB) in Precambrian South America. The new model reveals a relatively thin lithosphere throughout most of Precambrian South America (< 140 km). Comparing LAB depth with lithospheric age shows they are overall positively correlated, whereby the thickest lithosphere occurs in the relatively small Saõ Francisco craton (200 km). However, within the larger Amazonian craton the younger lithosphere is thicker, indicating that locally even larger cratons are not protected from erosion or reworking of the lithosphere.

Constraining Source Locations of Shallow Subduction Megathrust Earthquakes in 1-D and 3-D Velocity Models - A Case Study of the 2002 Mw=6.4 Osa Earthquake, Costa Rica

NASA Astrophysics Data System (ADS)

Grevemeyer, I.; Arroyo, I. G.

2015-12-01

Earthquake source locations are generally routinely constrained using a global 1-D Earth model. However, the source location might be associated with large uncertainties. This is definitively the case for earthquakes occurring at active continental margins were thin oceanic crust subducts below thick continental crust and hence large lateral changes in crustal thickness occur as a function of distance to the deep-sea trench. Here, we conducted a case study of the 2002 Mw 6.4 Osa thrust earthquake in Costa Rica that was followed by an aftershock sequence. Initial relocations indicated that the main shock occurred fairly trenchward of most large earthquakes along the Middle America Trench off central Costa Rica. The earthquake sequence occurred while a temporary network of ocean-bottom-hydrophones and land stations 80 km to the northwest were deployed. By adding readings from permanent Costa Rican stations, we obtain uncommon P wave coverage of a large subduction zone earthquake. We relocated this catalog using a nonlinear probabilistic approach using a 1-D and two 3-D P-wave velocity models. The 3-D model was either derived from 3-D tomography based on onshore stations and a priori model based on seismic refraction data. All epicentres occurred close to the trench axis, but depth estimates vary by several tens of kilometres. Based on the epicentres and constraints from seismic reflection data the main shock occurred 25 km from the trench and probably along the plate interface at 5-10 km depth. The source location that agreed best with the geology was based on the 3-D velocity model derived from a priori data. Aftershocks propagated downdip to the area of a 1999 Mw 6.9 sequence and partially overlapped it. The results indicate that underthrusting of the young and buoyant Cocos Ridge has created conditions for interpolate seismogenesis shallower and closer to the trench axis than elsewhere along the central Costa Rica margin.

Crustal structure across the lateral edge of the Southern Tyrrhenian slab

NASA Astrophysics Data System (ADS)

Pio Lucente, Francesco; Piana Agostinetti, Nicola; Di Bona, Massimo; Govoni, Aladino; Bianchi, Irene

2015-04-01

In the southeastern corner of the Tyrrhenian basin, in the central Mediterranean Sea, a tight alignment of earthquakes along a well-defined Benioff zone reveals the presence of one of the narrowest active trenches worldwide, where one of the last fragments of the former Tethys ocean is consumed. Seismic tomography furnishes snapshot images of the present-day position and shape of this slab. Through receiver function analysis we investigate the layered structures overlying the slab. We compute receiver functions from the P-coda of teleseismic events at 13 temporary station deployed during the "Messina 1908-2008" research project (Margheriti, 2008), and operating for an average period of 15 months each. The crustal and uppermost mantle structure has been investigated using a trans-dimensional McMC algorithm developed by Piana Agostinetti and Malinverno (2010), obtaining a 1D S-wave velocity profile for each station. At three of the stations, operating for a longer period of time, the number and the azimuthal distribution of teleseisms allowed us to stack the RF data-set with back azimuth and to compute the harmonic expansion. The analysis of the back-azimuthal harmonics gave us insight on the presence of dipping interfaces and anisotropic layers at depth. The strike and the dip of interfaces and the anisotropic parameters have been quantified using the Neighbourhood Algorithm (Sambridge, 1999). Preliminary results highlight: (1) a neat differentiation of the isotropic S-wave velocity structure passing through the slab edge, from the tip of the Calabrian arc to the Peloritani Range, and (2) the presence of crustal complexities, such as dipping interfaces and anisotropic layers, both in the upper and lower crust. Margheriti, L. (2008), Understanding Crust Dynamics and Subduction in Southern Italy, Eos Trans. AGU, 89(25), 225-226, doi:10.1029/2008EO250002. Piana Agostinetti, N. and A. Malinverno (2010) Receiver Function inversion by trans-dimensional Monte Carlo sampling, Geophys. J. Int., 181(2) 858-872, doi: 10.1111/j.1365-246X.2010.04530.x Sambridge, M. (1999), Geophysical inversion with a neighbourhood algorithm-I. Searching a parameter space, Geophys. J. Int., 138, 479-494, doi:10.1046/j.1365-246X.1999.00876.x.

Seismic Interferometry at a Large, Dense Array: Capturing the Wavefield at the Source Physics Experiment

NASA Astrophysics Data System (ADS)

Matzel, E.; Mellors, R. J.; Magana-Zook, S. A.

2016-12-01

Seismic interferometry is based on the observation that the Earth's background wavefield includes coherent energy, which can be recovered by observing over long time periods, allowing the incoherent energy to cancel out. The cross correlation of the energy recorded at a pair of stations results in an estimate of the Green's Function (GF) and is equivalent to the record of a simple source located at one of the stations as recorded by the other. This allows high resolution imagery beneath dense seismic networks even in areas of low seismicity. The power of these inter-station techniques increases rapidly as the number of seismometers in a network increases. For large networks the number of correlations computed can run into the millions and this becomes a "big-data" problem where data-management dominates the efficiency of the computations. In this study, we use several methods of seismic interferometry to obtain highly detailed images at the site of the Source Physics Experiment (SPE). The objective of SPE is to obtain a physics-based understanding of how seismic waves are created at and scattered near the source. In 2015, a temporary deployment of 1,000 closely spaced geophones was added to the main network of instruments at the site. We focus on three interferometric techniques: Shot interferometry (SI) uses the SPE shots as rich sources of high frequency, high signal energy. Coda interferometry (CI) isolates the energy from the scattered wavefield of distant earthquakes. Ambient noise correlation (ANC) uses the energy of the ambient background field. In each case, the data recorded at one seismometer are correlated with the data recorded at another to obtain an estimate of the GF between the two. The large network of mixed geophone and broadband instruments at the SPE allows us to calculate over 500,000 GFs, which we use to characterize the site and measure the localized wavefield. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344

Updated Tomographic Seismic Imaging at Kilauea Volcano, Hawaii

NASA Astrophysics Data System (ADS)

Okubo, P.; Johnson, J.; Felts, E. S.; Flores, N.

2013-12-01

Improved and more detailed geophysical, geological, and geochemical observations and measurements at Kilauea, along with prolonged eruptions at its summit caldera and east rift zone, are encouraging more ambitious interpretation and modeling of volcanic processes over a range of temporal and spatial scales. We are updating three-dimensional models of seismic wave-speed distributions within Kilauea using local earthquake arrival time tomography to support waveform-based modeling of seismic source mechanisms. We start from a tomographic model derived from a combination of permanent seismic stations comprising the Hawaiian Volcano Observatory (HVO) seismographic network and a dense deployment of temporary stations in the Kilauea caldera region in 1996. Using P- and S-wave arrival times measured from the HVO network for local earthquakes from 1997 through 2012, we compute velocity models with the finite difference tomographic seismic imaging technique implemented by Benz and others (1996), and applied to numerous volcanoes including Kilauea. Particular impetus to our current modeling was derived from a focused effort to review seismicity occurring in Kilauea's summit caldera and adjoining regions in 2012. Our results reveal clear P-wave low-velocity features at and slightly below sea level beneath Kilauea's summit caldera, lying between Halemaumau Crater and the north-facing scarps that mark the southern caldera boundary. The results are also suggestive of changes in seismic velocity distributions between 1996 and 2012. One example of such a change is an apparent decrease in the size and southeastward extent, compared to the earlier model, of the low VP feature imaged with the more recent data. However, we recognize the distinct possibility that these changes are reflective of differences in earthquake and seismic station distributions in the respective datasets, and we need to further populate the more recent HVO seismicity catalogs to possibly address this concern. We also look forward to more complete implementation at HVO of seismic imaging techniques that use ambient seismic noise retrieved from continuous seismic recordings, and to using earthquake arrival times and ambient seismic noise jointly to tomographically image Kilauea.

Sources of high frequency seismic noise: insights from a dense network of ~250 stations in northern Alsace (France)

NASA Astrophysics Data System (ADS)

Vergne, Jerome; Blachet, Antoine; Lehujeur, Maximilien

2015-04-01

Monitoring local or regional seismic activity requires stations having a low level of background seismic noise at frequencies higher than few tenths of Hertz. Network operators are well aware that the seismic quality of a site depends on several aspects, among them its geological setting and the proximity of roads, railways, industries or trees. Often, the impact of each noise source is only qualitatively known which precludes estimating the quality of potential future sites before they are tested or installed. Here, we want to take advantage of a very dense temporary network deployed in Northern Alsace (France) to assess the effect of various kinds of potential sources on the level of seismic noise observed in the frequency range 0.2-50 Hz. In September 2014, more than 250 seismic stations (FairfieldNodal@ Zland nodes with 10Hz vertical geophone) have been installed every 1.5 km over a ~25km diameter disc centred on the deep geothermal sites of Soultz-sous-Forêts and Rittershoffen. This region exhibits variable degrees of human imprints from quite remote areas to sectors with high traffic roads and big villages. It also encompasses both the deep sedimentary basin of the Rhine graben and the piedmont of the Vosges massif with exposed bedrock. For each site we processed the continuous data to estimate probability density functions of the power spectral densities. At frequencies higher than 1 Hz most sites show a clear temporal modulation of seismic noise related to human activity with the well-known variations between day and night and between weekdays and weekends. Moreover we observe a clear evolution of the spatial distribution of seismic noise levels with frequency. Basically, between 0.5 and 4 Hz the geological setting modulates the level of seismic noise. At higher frequencies, the amplitude of seismic noise appears mostly related to the distance to nearby roads. Based on road maps and traffic estimation, a forward approach is performed to model the induced seismic noise. Effects of other types of seismic sources, such as industries or wind, are also observed but usually have a more limited spatial extension and a specific signature in the spectrograms.

Temporary Urine and Brine Stowage System (TUBSS) Development

NASA Technical Reports Server (NTRS)

Dries, Kevin; Carrigan, Caitlin

2011-01-01

International Space Station (ISS) crew liquid human waste is treated with chromic and sulfuric acids to maintain stability prior to processing to recover water. This pre-treated urine (PTU) and its processed by-product, brine, are highly toxic fluids that require special containment for on-orbit stowage. The temporary urine and brine stowage syste m (TUBSS) is an assembly used to store and transfer pre-treated urine (PTU) and brine for processing or disposal at a later date. This paper describes the development of the TUBSS, including design for two-fault tolerance and materials selection to maintain a soft, collapsible container. In addition, this paper will provide results of testing as well as lessons learned from the project, culminating in the successful launch of the hardware.

Space vehicle field unit and ground station system

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

Judd, Stephen; Dallmann, Nicholas; Delapp, Jerry

A field unit and ground station may use commercial off-the-shelf (COTS) components and share a common architecture, where differences in functionality are governed by software. The field units and ground stations may be easy to deploy, relatively inexpensive, and be relatively easy to operate. A novel file system may be used where datagrams of a file may be stored across multiple drives and/or devices. The datagrams may be received out of order and reassembled at the receiving device.

Space vehicle field unit and ground station system

DOEpatents

Judd, Stephen; Dallmann, Nicholas; Delapp, Jerry; Proicou, Michael; Seitz, Daniel; Michel, John; Enemark, Donald

2016-10-25

A field unit and ground station may use commercial off-the-shelf (COTS) components and share a common architecture, where differences in functionality are governed by software. The field units and ground stations may be easy to deploy, relatively inexpensive, and be relatively easy to operate. A novel file system may be used where datagrams of a file may be stored across multiple drives and/or devices. The datagrams may be received out of order and reassembled at the receiving device.

Development of an Open Source, Air-Deployable Weather Station

NASA Astrophysics Data System (ADS)

Krejci, A.; Lopez Alcala, J. M.; Nelke, M.; Wagner, J.; Udell, C.; Higgins, C. W.; Selker, J. S.

2017-12-01

We created a packaged weather station intended to be deployed in the air on tethered systems. The device incorporates lightweight sensors and parts and runs for up to 24 hours off of lithium polymer batteries, allowing the entire package to be supported by a thin fiber. As the fiber does not provide a stable platform, additional data (pitch and roll) from typical weather parameters (e.g. temperature, pressure, humidity, wind speed, and wind direction) are determined using an embedded inertial motion unit. All designs are open sourced including electronics, CAD drawings, and descriptions of assembly and can be found on the OPEnS lab website at http://www.open-sensing.org/lowcost-weather-station/. The Openly Published Environmental Sensing Lab (OPEnS: Open-Sensing.org) expands the possibilities of scientific observation of our Earth, transforming the technology, methods, and culture by combining open-source development and cutting-edge technology. New OPEnS labs are now being established in India, France, Switzerland, the Netherlands, and Ghana.

Broadband Ground Motion Observation and Simulation for the 2016 Kumamoto Earthquake

NASA Astrophysics Data System (ADS)

Miyake, H.; Chimoto, K.; Yamanaka, H.; Tsuno, S.; Korenaga, M.; Yamada, N.; Matsushima, T.; Miyakawa, K.

2016-12-01

During the 2016 Kumamoto earthquake, strong motion data were widely recorded by the permanent dense triggered strong motion network of K-NET/KiK-net and seismic intensity meters installed by local government and JMA. Seismic intensities close to the MMI 9-10 are recorded twice at the Mashiki town, and once at the Nishihara village and KiK-net Mashiki (KMMH16 ground surface). Near-fault records indicate extreme ground motion exceeding 400 cm/s in 5% pSv at a period of 1 s for the Mashiki town and 3-4 s for the Nishihara village. Fault parallel velocity components are larger between the Mashiki town and the Nishihara village, on the other hand, fault normal velocity components are larger inside the caldera of the Aso volcano. The former indicates rupture passed through along-strike stations, and the latter stations located at the forward rupture direction (e.g., Miyatake, 1999). In addition to the permanent observation, temporary continuous strong motion stations were installed just after the earthquake in the Kumamoto city, Mashiki town, Nishihara village, Minami-Aso village, and Aso town, (e.g., Chimoto et al., 2016; Tsuno et al., 2016; Yamanaka et al. 2016). This study performs to estimate strong motion generation areas for the 2016 Kumamoto earthquake sequence using the empirical Green's function method, then to simulate broadband ground motions for both the permanent and temporary strong motion stations. Currently the target period range is between 0.1 s to 5-10 s due to the signal-to-noise ratio of element earthquakes used for the empirical Green's functions. We also care fault dimension parameters N within 4 to 10 to avoid spectral sags and artificial periodicity. The simulated seismic intensities as well as fault normal and parallel velocity components will be discussed.