A Tale of Two Cataclysmic Earthquakes: 39 and 52 kyr BP, Dead Sea Transform, Israel; a Multi-archive Study

NASA Astrophysics Data System (ADS)

Kagan, E. J.; Stein, M.; Bar-Matthews, M.; Agnon, A.

2007-12-01

We have documented earthquake histories in four lacustrine sites and a cave in the Dead Sea Transform region in central Israel. The lacustrine Lake Lisan (last Glacial paleo-Dead Sea) sites include: Massada Plain (M1b), Perazim (PZ1), Tovlan (NT), and Tamar (TM). They are up to 110 kms apart, along the Dead Sea Basin. These lacustrine sites have a variety of deformed marls (e.g. brecciated, homogenated, folded, and/or faulted). Except for the more fluvial NT site, where there is only one breccia layer, the sites show numerous (up to 29) earthquake events. Brecciated marls have been shown to be valuable earthquake markers by correlation with historical earthquakes and by their relationship to intraformational fault scarps (Agnon et al., 2006). The Soreq Cave, a carbonate cave richly decorated with speleothems, is 40 km west of the Dead Sea Basin, near the town Bet Shemesh. Earthquake damage in the cave includes collapsed stalactites and ceilings and severed stalagmites. During the last Glacial time period the cave, more distant from the Transform than the lake sites, experienced ~7 damaging events, documented by tens of dated collapses. The Soreq cave collapses have been shown to be viable earthquake markers by correlation to lacustrine documented seismic events and by absence of potential non-seismic sources of damage in the cave (Kagan et al., 2005). All the earthquake evidence, speleological and lacustrine, was rigorously dated by high resolution mass spectrometry by MC-ICP-MS at the Geological Survey of Israel. Both the Soreq cave and the Lisan sediments have been studied intensely for paleo- climate purposes in other studies. From these different and distant paleoseismic sites two events stand out. At ~39±1 ka and ~52±2 ka there is paleoseismic evidence at 5 and 3 sites, respectively. The later event, ~39±1 ka, has left evidence of brecciated marls at all four Lisan sites (with extremely thick seismites at the PZ1 site and the only breccia at the NT site) as well as five well-constrained collapses in different areas of the Soreq cave. The ~52±2 ka seismic event has left evidence at M1b (a closely spaced doublet of seismites), at PZ1 (followed by a period with numerous (8) and very thick (up to 48 cm) seismites) and at the cave site (3 collapses). We suggest that these seismic events are large-earthquakes, sufficiently strong to cause cave collapses and lake bottom brecciation in numerous and distant sites in very different kinds of sediments. We suggest that these large events are representatives of the largest magnitude earthquakes in the Dead Sea region. We extrapolate the frequency-size statistics from the instrumental data using a power-law (Gutenberg-Richter) to estimate ranges of magnitude for these cataclysmic events.

The DESIRE Airborne gravity project in the Dead Sea Basin and 3D numerical gravity modeling

NASA Astrophysics Data System (ADS)

Choi, Sungchan; Götze, Hans-Jürgen; Meyer, Uwe; Desire-Group

2010-05-01

This geo-scientific research focuses on the geological setting of the Dead Sea Transform (DST) and the Dead Sea Basin (DSB) and its resulting pull-apart basins. Since the late 1970s, crustal scale geophysical experiments have been carried out in this region. However, the nature of the crust underlying the eastern and western shoulders of the DSB and underneath the DST itself is still a hotly debated topic among researchers. To address one of the central questions of plate tectonics - How do large transform systems work and what are their typical features? - An international geoscientific Dead Sea Integrated Research project (DESIRE) is being conducted by colleagues from Germany, Israel, Palestine, and Jordan. In order to provide a high resolution gravity database that support 3D numerical modeling and hence a more comprehensive understanding of the nature and segmentation of the DST, an airborne gravity survey as a part of the DESIRE project has been carried out from February to March 2007. The airborne gravity survey covered the DST from Elat/Aqaba in the South to the northern rim of the Dead Sea. The low speed and terrain-following helicopter gravity flights were performed to acquire the highest possible data quality. In total, 32 north-south profiles and 16 west-east profiles crossing the DST have been measured. Most of the profiles concentrated in areas that lacked terrestrial gravity data coverage, e. g. over the shoulders of the DSB. The airborne gravity data are merged with existing conventional (terrestrial) data sets to provide a seamless gravity map of the area of interest. The results of the 3D gravity modelling based the GPS analysis, magnetic field characters, seismic researches and analysis of earthquake data allow us to propose that (1) the DSB is divided into two tectonic blocks by the region between the Lisan peninsula and the southern margin of the northern DSB and (2) the tectonic system in the DSB is defined as a counter-clockwise rotating pull apart basin due to the ‘Riedel flaking', by which the northern DSB is rotated counter-clockwise from the region and the southern DSB to the opposite direction. The salt diapir below the Dead Sea is suspected to be migrated from the Lisan peninsula to present region by the rotation of the northern DSB, while the Sedom diapir is extended to the SE direction. The Almacik flake along the North Anatolian fault, Turkey is probably another example of such basin.

Scientific evidence of the therapeutic effects of dead sea treatments: a systematic review.

PubMed

Katz, Uriel; Shoenfeld, Yehuda; Zakin, Varda; Sherer, Yaniv; Sukenik, Shaul

2012-10-01

The Dead Sea, the deepest and most saline lake on earth, has been known from biblical times for its healing properties. The aim of this systematic review was to present critically the level of evidence for the claims of therapeutic effects of Dead Sea treatments in several rheumatologic diseases and psoriasis as well as to review these treatments' safety. All articles cited in MEDLINE under the query, "Dead Sea," were reviewed. We found bona fide evidence that Dead Sea treatments are especially effective in psoriasis due to both the special characteristics of solar ultraviolet radiation in the Dead Sea and the Dead Sea water balneotherapy. Dead Sea mud and Dead Sea balneotherapy have been found to be beneficial in rheumatologic diseases, including rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, and knee osteoarthritis. In the safety analysis, we found no evidence for an increase in skin neoplasia, although skin actinic damage seems to be increased in patients treated in the Dead Sea. Dead Sea treatments do not lead to worsening of blood pressure. Substantial ingestion of Dead Sea water (generally in unusual near-drowning cases) is toxic and can result in cardiac rhythm disturbances because of electrolyte concentration abnormalities. Laboratory analysis of Dead Sea mud did not reveal mineral concentrations that could represent a health concern for their intended use. Dead Sea treatments are beneficial in several rheumatologic diseases and psoriasis and have a good safety profile. Copyright © 2012 Elsevier Inc. All rights reserved.

Gravity field over the Sea of Galilee: Evidence for a composite basin along a transform fault

USGS Publications Warehouse

Ben-Avraham, Z.; ten Brink, Uri S.; Bell, R.; Reznikov, M.

1996-01-01

The Sea of Galilee (Lake Kinneret) is located at the northern portion of the Kinneret-Bet Shean basin, in the northern Dead Sea transform. Three hundred kilometers of continuous marine gravity data were collected in the lake and integrated with land gravity data to a distance of more than 20 km around the lake. Analyses of the gravity data resulted in a free-air anomaly map, a variable density Bouguer anomaly map, and a horizontal first derivative map of the Bouguer anomaly. These maps, together with gravity models of profiles across the lake and the area south of it, were used to infer the geometry of the basins in this region and the main faults of the transform system. The Sea of Galilee can be divided into two units. The southern half is a pull-apart that extends to the Kinarot Valley, south of the lake, whereas the northern half was formed by rotational opening and transverse normal faults. The deepest part of the basinal area is located well south of the deepest bathymetric depression. This implies that the northeastern part of the lake, where the bathymetry is the deepest, is a young feature that is actively subsiding now. The pull-apart basin is almost symmetrical in the southern part of the lake and in the Kinarot Valley south of the lake. This suggests that the basin here is bounded by strike-slip faults on both sides. The eastern boundary fault extends to the northern part of the lake, while the western fault does not cross the northern part. The main factor controlling the structural complexity of this area is the interaction of the Dead Sea transform with a subperpendicular fault system and rotated blocks.

77 FR 64373 - Culturally Significant Objects Imported for Exhibition Determinations: “The Dead Sea Scrolls...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-19

... Determinations: ``The Dead Sea Scrolls: Life and Faith in Ancient Times,'' Formerly Titled ``The Dead Sea Scrolls... the Department of State pertaining to the exhibition ``The Dead Sea Scrolls: Life and Faith in Biblical Times.'' The referenced notice is corrected here to change the exhibition name to ``The Dead Sea...

78 FR 62354 - Culturally Significant Objects Imported for Exhibition Determinations: “The Dead Sea Scrolls...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-18

... Determinations: ``The Dead Sea Scrolls: Life and Faith in Ancient Times'' Formerly Titled ``The Dead Sea Scrolls... Department of State pertaining to the exhibition ``The Dead Sea Scrolls: Life and Faith in Biblical Times... of the Federal Register (volume 77, number 203) to change the exhibition name to ``The Dead Sea...

78 FR 24462 - Culturally Significant Objects Imported for Exhibition; Determinations: “The Dead Sea Scrolls...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-25

...; Determinations: ``The Dead Sea Scrolls: Life and Faith in Ancient Times'' Formerly Titled ``The Dead Sea Scrolls... Department of State pertaining to the exhibition ``The Dead Sea Scrolls: Life and Faith in Biblical Times... of the Federal Register (volume 77, number 203) to change the exhibition name to ``The Dead Sea...

78 FR 16565 - Culturally Significant Objects Imported for Exhibition Determinations: “The Dead Sea Scrolls...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-15

... Determinations: ``The Dead Sea Scrolls: Life and Faith in Ancient Times'' Formerly Titled ``The Dead Sea Scrolls... Department of State pertaining to the exhibition ``The Dead Sea Scrolls: Life and Faith in Biblical Times... of the Federal Register (volume 77, number 203) to change the exhibition name to ``The Dead Sea...

Raising the Dead without a Red Sea-Dead Sea Canal? A hydro-economic-institutional analysis

NASA Astrophysics Data System (ADS)

Rosenberg, D. E.

2010-12-01

Presently, just 100 million cubic meters per year (MCM/year) of the 1,000+ MCM/year that historically flowed in the lower Jordan River reach the Dead Sea. Israeli, Jordanian, and Syrian dam and extraction projects built over seven decades have principally caused the reduced flow, associated falling Dead Sea level, shrinking surface area, sink holes, salinity, and other catastrophic problems. These problems will be magnified in the face of up to 20% reductions in precipitation expected with climate change. The fix proposed by Jordan, Israel, and Palestine—and now under study by the World Bank—envisions building a $US 5 billion multipurpose canal from the Red Sea to the Dead Sea that would also generate hydropower and desalinated water. Yet alternatives to raise the Dead Sea level that could take advantage of hydrologic variability remain unstudied. Here we show system-wide hydrologic and economic impacts of and discusses institutional management for alternatives to raise the Dead Sea level. Hydro-economic model results for the inter-tied Israel-Jordan-Palestinian water systems show the desalination component of the Red Sea-Dead Sea project is economically unviable. Further, many decentralized new supply, wastewater reuse, conveyance, conservation, and leak reduction projects and programs in each country together increase economic benefits and can reliably deliver up to 900 MCM/year to the Dead Sea. In all cases, results show that net benefits fall and water scarcity rises as the flow volume delivered to the Dead Sea increases. These findings suggest that (i) each country has little individual incentive to allow water to flow to the Dead Sea, and (ii) outside institutions—such as the World Bank—that seek to raise the Dead should instead offer the countries direct incentives to deliver water rather than build them new infrastructure. The work expands the set of viable options to raise the Dead Sea level and can help the World Bank and others recommend whether to move forward with the Red Sea-Dead Sea project.

The major tectonic boundaries of the Northern Red Sea rift, Egypt derived from geophysical data analysis

NASA Astrophysics Data System (ADS)

Saleh, Salah; Pamukçu, Oya; Brimich, Ladislav

2017-09-01

In the present study, we have attempted to map the plate boundary between Arabia and Africa at the Northern Red Sea rift region including the Suez rift, Gulf of Aqaba-Dead Sea transform and southeastern Mediterranean region by using gravity data analysis. In the boundary analysis method which was used; low-pass filtered gravity anomalies of the Northern Red Sea rift region were computed. Different crustal types and thicknesses, sediment thicknesses and different heat flow anomalies were evaluated. According to the results, there are six subzones (crustal blocks) separated from each other by tectonic plate boundaries and/or lineaments. It seems that these tectonic boundaries reveal complex structural lineaments, which are mostly influenced by a predominant set of NNW-SSE to NW-SE trending lineaments bordering the Red Sea and Suez rift regions. On the other side, the E-W and N-S to NNE-SSW trended lineaments bordering the South-eastern Mediterranean, Northern Sinai and Aqaba-Dead Sea transform regions, respectively. The analysis of the low pass filtered Bouguer anomaly maps reveals that the positive regional anomaly over both the Red Sea rift and South-eastern Mediterranean basin subzones are considered to be caused by the high density of the oceanic crust and/or the anomalous upper mantle structures beneath these regions whereas, the broad medium anomalies along the western half of Central Sinai with the Suez rift and the Eastern Desert subzones are attributed to low-density sediments of the Suez rift and/or the thick upper continental crustal thickness below these zones. There are observable negative anomalies over the Northern Arabia subzone, particularly in the areas covered by Cenozoic volcanics. These negative anomalies may be attributed to both the low densities of the surface volcanics and/or to a very thick upper continental crust. On the contrary, the negative anomaly which belongs to the Gulf of Aqaba-Dead Sea transform zone is due to crustal thickening (with limited heat flow values) below this region. Additionally in this study, the crustal thinning was investigated with heat flow, magnetic and free air gravity anomalies in the Northern Red Sea rift region. In fact, the crustal thinning of the study area was also proportional to the regions of observable high heat flow values. Finally, our results were found to be well correlated with the topography, free air, aeromagnetic and heat flow dataset profiles crossing most of the study area.

Aeromagnetic evidence for a major strike-slip fault zone along the boundary between the Weddell Sea Rift and East Antarctica

NASA Astrophysics Data System (ADS)

Jordan, T. A.; Ferraccioli, F.; Ross, N.; Siegert, M. J.; Corr, H.; Leat, P. T.; Bingham, R. G.; Rippin, D. M.; le Brocq, A.

2012-04-01

The >500 km wide Weddell Sea Rift was a major focus for Jurassic extension and magmatism during the early stages of Gondwana break-up, and underlies the Weddell Sea Embayment, which separates East Antarctica from a collage of crustal blocks in West Antarctica. Here we present new aeromagnetic data combined with airborne radar and gravity data collected during the 2010-11 field season over the Institute and Moeller ice stream in West Antarctica. Our interpretations identify the major tectonic boundaries between the Weddell Sea Rift, the Ellsworth-Whitmore Mountains block and East Antarctica. Digitally enhanced aeromagnetic data and gravity anomalies indicate the extent of Proterozoic basement, Middle Cambrian rift-related volcanic rocks, Jurassic granites, and post Jurassic sedimentary infill. Two new joint magnetic and gravity models were constructed, constrained by 2D and 3D magnetic depth-to-source estimates to assess the extent of Proterozoic basement and the thickness of major Jurassic intrusions and post-Jurassic sedimentary infill. The Jurassic granites are modelled as 5-8 km thick and emplaced at the transition between the thicker crust of the Ellsworth-Whitmore Mountains block and the thinner crust of the Weddell Sea Rift, and within the Pagano Fault Zone, a newly identified ~75 km wide left-lateral strike-slip fault system that we interpret as a major tectonic boundary between East and West Antarctica. We also suggest a possible analogy between the Pagano Fault Zone and the Dead Sea transform. In this scenario the Jurassic Pagano Fault Zone is the kinematic link between extension in the Weddell Sea Rift and convergence across the Pacific margin of West Antarctica, as the Dead Sea transform links Red Sea extension to compression within the Zagros Mountains.

Deciphering The Fall And Rise Of The Dead Sea In Relation To Solar Forcing

NASA Astrophysics Data System (ADS)

Yousef, Shahinaz M.

2005-03-01

Solar Forcing on closed seas and Lakes is space time dependent. The Cipher of the Dead Sea level variation since 1200 BC is solved in the context of millenium and Wolf-Gleissberg solar cycles time scales. It is found that the pattern of Dead Sea level variation follows the pattern of major millenium solar cycles. The 70 m rise of Dead Sea around 1AD is due to the forcing of the maximum millenium major solar cycle. Although the pattern of the Dead Sea level variation is almost identical to major solar cycles pattern between 1100 and 1980 AD, there is a dating problem of the Dead Sea time series around 1100-1300 AD that time. A discrepancy that should be corrected for the solar and Dead Sea series to fit. Detailed level variations of the Dead Sea level for the past 200 years are solved in terms of the 80-120 years solar Wolf-Gliessberg magnetic cycles. Solar induced climate changes do happen at the turning points of those cycles. Those end-start and maximum turning points are coincident with the change in the solar rotation rate due to the presence of weak solar cycles. Such weak cycles occur in series of few cycles between the end and start of those Wolf-Gleissberg cycles. Another one or two weak r solar cycle occur following the maximum of those Wolf-Gleissberg cycles. Weak cycles induce drop in the energy budget emitted from the sun and reaching the Earth thus causing solar induced climate change. An 8 meter sudden rise of Dead Sea occur prior 1900 AD due to positive solar forcing of the second cycle of the weak cycles series on the Dead Sea. The same second weak cycle induced negative solar forcing on Lake Chad. The first weak solar cycle forced Lake Victoria to rise abruptly in 1878. The maximum turning point of the solar Wolf-Gleissberg cycle induced negative forcing on both the Aral Sea and the Dead Sea causing their shrinkage to an alarming reduced area ever since. On the other hand, few years delayed positive forcing caused Lake Chad and the Equatorial African lakes to rise abruptly by several meters. Since the present solar cycle number 23 is the first weak cycle of a series, and since it caused 1.6 m sharp rise in Lake Victoria in 1997, then there is a high probability that the Dead Sea will rise by the beginning of the second weak cycle in few years time. And since both the Aral Sea and the Dead Sea are very much in coherence since the late 1950s, then it is rather likely that the Aral Sea will rise with God's wish in the near future. However it is also demanded that Israel should allow more water of the Jordan River to feed the Dead Sea before its real death. Plans for joining the Dead sea to the Red and or to the Mediterranean Seas should be cancelled owing the damaging harm it will cause the Dead Sea as a perfect indicator of solar induced climate change on one hand. On the other hand, the Dead Sea time series always show abrupt changes that can be as high as 70 m; if we add to this a planned artificial rise of the Dead Sea to its level of the thirties, then a damaging flooding effect will ruin the establishments and environment greatly.

A step forward in understanding step-overs: the case of the Dead Sea Fault in northern Israel

NASA Astrophysics Data System (ADS)

Dembo, Neta; Granot, Roi; Hamiel, Yariv

2017-04-01

The rotational deformation field around step-overs between segments of strike-slip faults is poorly resolved. Vertical-axis paleomagnetic rotations can be used to characterize the deformation field, and together with mechanical modeling, can provide constraints on the characteristics of the adjacent fault segments. The northern Dead Sea Fault, a major segmented sinistral transform fault that straddles the boundary between the Arabian Plate and Sinai Subplate, offers an appropriate tectonic setting for our detailed mechanical and paleomagnetic investigation. We examine the paleomagnetic vertical-axis rotations of Neogene-Pleistocene basalt outcrops surrounding a right step-over between two prominent segments of the fault: the Jordan Gorge section and the Hula East Boundary Fault. Results from 20 new paleomagnetic sites reveal significant (>20˚) counterclockwise rotations within the step-over and small clockwise rotations in the vicinity. Sites located further (>2.5 km) away from the step-over generally experience negligible to minor rotations. Finally, we construct a mechanical model guided by the observed rotational field that allows us to characterize the structural, mechanical and kinematic behavior of the Dead Sea Fault in northern Israel.

Synoptic conditions of fine-particle transport to the last interglacial Red Sea-Dead Sea from Nd-Sr compositions of sediment cores

NASA Astrophysics Data System (ADS)

Palchan, Daniel; Stein, Mordechai; Goldstein, Steven L.; Almogi-Labin, Ahuva; Tirosh, Ofir; Erel, Yigal

2018-01-01

The sediments deposited at the depocenter of the Dead Sea comprise high-resolution archive of hydrological changes in the lake's watershed and record the desert dust transport to the region. This paper reconstructs the dust transport to the region during the termination of glacial Marine Isotope Stage 6 (MIS 6; ∼135-129 ka) and the last interglacial peak period (MIS5e, ∼129-116 ka). We use chemical and Nd and Sr isotope compositions of fine detritus material recovered from sediment core drilled at the deepest floor of the Dead Sea. The data is integrated with data achieved from cores drilled at the floor of the Red Sea, thus, forming a Red Sea-Dead Sea transect extending from the desert belt to the Mediterranean climate zone. The Dead Sea accumulated flood sediments derived from three regional surface cover types: settled desert dust, mountain loess-soils and loess-soils filling valleys in the Dead Sea watershed termed here "Valley Loess". The Valley Loess shows a distinct 87Sr/86Sr ratio of 0.7081 ± 1, inherited from dissolved detrital calcites that originate from dried waterbodies in the Sahara and are transported with the dust to the entire transect. Our hydro-climate and synoptic conditions reconstruction illustrates the following history: During glacial period MIS6, Mediterranean cyclones governed the transport of Saharan dust and rains to the Dead Sea watershed, driving the development of both mountain soils and Valley Loess. Then, at Heinrich event 11, dry western winds blew Saharan dust over the entire Red Sea - Dead Sea transect marking latitudinal expansion of the desert belt. Later, when global sea-level rose, the Dead Sea watershed went through extreme aridity, the lake retreated, depositing salt and accumulating fine detritus of the Valley Loess. During peak interglacial MIS 5e, enhanced flooding activity flushed the mountain soils and fine detritus from all around the Dead Sea and Red Sea, marking a significant "contraction" of the desert belt. At the end of MIS 5e the effect of the regional precipitation diminished and the Dead Sea and Red Sea areas re-entered sever arid conditions with extensive salt deposition at the Dead Sea.

Safety evaluation of traces of nickel and chrome in cosmetics: The case of Dead Sea mud.

PubMed

Ma'or, Ze'evi; Halicz, Ludwik; Portugal-Cohen, Meital; Russo, Matteo Zanotti; Robino, Federica; Vanhaecke, Tamara; Rogiers, Vera

2015-12-01

Metal impurities such as nickel and chrome are present in natural ingredients-containing cosmetic products. These traces are unavoidable due to the ubiquitous nature of these elements. Dead Sea mud is a popular natural ingredient of cosmetic products in which nickel and chrome residues are likely to occur. To analyze the potential systemic and local toxicity of Dead Sea mud taking into consideration Dead Sea muds' natural content of nickel and chrome. The following endpoints were evaluated: (Regulation No. 1223/20, 21/12/2009) systemic and (SCCS's Notes of Guidance) local toxicity of topical application of Dead Sea mud; health reports during the last five years of commercial marketing of Dead Sea mud. Following exposure to Dead Sea mud, MoS (margin of safety) calculations for nickel and chrome indicate no toxicological concern for systemic toxicity. Skin sensitization is also not to be expected by exposure of normal healthy skin to Dead Sea mud. Topical application, however, is not recommended for already nickel-or chrome-sensitized persons. As risk assessment of impurities present in cosmetics may be a difficult exercise, the case of Dead Sea mud is taken here as an example of a natural material that may contain traces of unavoidable metals. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Shallow lithological structure across the Dead Sea Transform derived from geophysical experiments

USGS Publications Warehouse

Stankiewicz, J.; Munoz, G.; Ritter, O.; Bedrosian, P.A.; Ryberg, T.; Weckmann, U.; Weber, M.

2011-01-01

In the framework of the DEad SEa Rift Transect (DESERT) project a 150 km magnetotelluric profile consisting of 154 sites was carried out across the Dead Sea Transform. The resistivity model presented shows conductive structures in the western section of the study area terminating abruptly at the Arava Fault. For a more detailed analysis we performed a joint interpretation of the resistivity model with a P wave velocity model from a partially coincident seismic experiment. The technique used is a statistical correlation of resistivity and velocity values in parameter space. Regions of high probability of a coexisting pair of values for the two parameters are mapped back into the spatial domain, illustrating the geographical location of lithological classes. In this study, four regions of enhanced probability have been identified, and are remapped as four lithological classes. This technique confirms the Arava Fault marks the boundary of a highly conductive lithological class down to a depth of ???3 km. That the fault acts as an impermeable barrier to fluid flow is unusual for large fault zone, which often exhibit a fault zone characterized by high conductivity and low seismic velocity. At greater depths it is possible to resolve the Precambrian basement into two classes characterized by vastly different resistivity values but similar seismic velocities. The boundary between these classes is approximately coincident with the Al Quweira Fault, with higher resistivities observed east of the fault. This is interpreted as evidence for the original deformation along the DST originally taking place at the Al Quweira Fault, before being shifted to the Arava Fault. 

75 FR 47825 - Emergency Exemption; Issuance of Emergency Permit to Rehabilitate Sea Turtles Affected by the...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-09

... tag live sea turtles; transport live and dead sea turtles to rehabilitation facilities, satellite transmitter attachment sites, and necropsy sites and necropsy dead sea turtles and collect samples; examine gut contents from dead sea turtles; attach satellite transmitters to nesting Kemp's ridley turtles...

Natural Oxidation of Bromide to Bromine in Evaporated Dead Sea Brines

NASA Astrophysics Data System (ADS)

Gavrieli, Ittai; Golan, Rotem; Lazar, Boaz; Baer, Gidi; Zakon, Yevgeni; Ganor, Jiwchar

2016-04-01

Highly evaporated Dead Sea brines are found in isolated sinkholes along the Dead Sea. Many of these brines reach densities of over 1.3 kg/L and pH<5 and are the product of evaporation of Dead Sea brine that drain into the sinkholes. The low pH and the reddish to brownish hue of these brines were an enigma until recently. Despite the rather high total alkalinity (TA) of the Dead Sea (3.826 mmol/kg) the pH of the Dead Sea brine is known to be slightly acidic with a value of ~6.3. In comparison, seawater with the same alkalinity would have a pH value well above 8.3, meaning that H+ activity is 100 fold lower than that of Dead Sea brine. In the present work we assess the apparent dissociation constant value of boric acid (K`B) for the Dead Sea brine and use it to explain the brine's low pH value. We then show that pH decreases further as the brine evaporates and salinity increases. Finally we explain the reddish hue of the hypersaline brines in the sinkholes as due to the presence of dissolved bromine. The latter is the product of oxidation of dissolved bromide, a process that is enabled by the low pH of the hypersaline brines and their high bromide concentration.

Regional seismic wave propagation (Lg and Sn) and Pn attenuation in the Arabian Plate and surrounding regions

NASA Astrophysics Data System (ADS)

Al-Damegh, Khaled; Sandvol, Eric; Al-Lazki, Ali; Barazangi, Muawia

2004-05-01

Continuous recordings of 17 broadband and short-period digital seismic stations from a newly established seismological network in Saudi Arabia, along with digital recordings from the broadband stations of the GSN, MEDNET, GEOFON, a temporary array in Saudi Arabia, and temporary short period stations in Oman, were analysed to study the lithospheric structure of the Arabian Plate and surrounding regions. The Arabian Plate is surrounded by a variety of types of plate boundaries: continental collision (Zagros Belt and Bitlis Suture), continental transform (Dead Sea fault system), young seafloor spreading (Red Sea and the Gulf of Aden) and oceanic transform (Owen fracture zone). Also, there are many intraplate Cenozoic processes such as volcanic eruptions, faulting and folding that are taking place. We used this massive waveform database of more than 6200 regional seismograms to map zones of blockage, inefficient and efficient propagation of the Lg and Sn phases in the Middle East and East Africa. We observed Lg blockage across the Bitlis Suture and the Zagros fold and thrust belt, corresponding to the boundary between the Arabian and Eurasian plates. This is probably due to a major lateral change in the Lg crustal waveguide. We also observed inefficient Lg propagation along the Oman mountains. Blockage and inefficient Sn propagation is observed along and for a considerable distance to the east of the Dead Sea fault system and in the northern portion of the Arabian Plate (south of the Bitlis Suture). These mapped zones of high Sn attenuation, moreover, closely coincide with extensive Neogene and Quaternary volcanic activity. We have also carefully mapped the boundaries of the Sn blockage within the Turkish and Iranian plateaus. Furthermore, we observed Sn blockage across the Owen fracture zone and across some segments of the Red Sea. These regions of high Sn attenuation most probably have anomalously hot and possibly thin lithospheric mantle (i.e. mantle lid). A surprising result is the efficient propagation of Sn across a segment of the Red Sea, an indication that active seafloor spreading is not continuous along the axis of the Red Sea. We also investigated the attenuation of Pn phase (QPn) for 1-2 Hz along the Red Sea, the Dead Sea fault system, within the Arabian Shield and in the Arabian Platform. Consistent with the Sn attenuation, we observed low QPn values of 22 and 15 along the western coast of the Arabian Plate and along the Dead Sea fault system, respectively, for a frequency of 1.5 Hz. Higher QPn values of the order of 400 were observed within the Arabian Shield and Platform for the same frequency. Our results based on Sn and Pn observations along the western and northern portions of the Arabian Plate imply the presence of a major anomalously hot and thinned lithosphere in these regions that may be caused by the extensive upper mantle anomaly that appears to span most of East Africa and western Arabia.

Present-Day Kinematics of the Dead Sea Transform and Internal Deformation within the Sinai and Arabian Plates

NASA Astrophysics Data System (ADS)

Gomez, F. G.; Yassminh, R.; Cochran, W. J.; Reilinger, R. E.; Barazangi, M.

2015-12-01

An updated GPS velocity field along the Dead Sea Fault (DSF) provides a basis for assessing off-transform strain within the Sinai and Arabian plates along entire length of this left-lateral, continental transform. As one of the main tectonic elements in the eastern Mediterranean region, an improved kinematic view of the DSF elucidates the broader understanding of the regional tectonic framework, as well as contributes to refining the earthquake hazard assessment. Reconciling short-term (geodetic) measurements of crustal strain with neotectonic data on fault movements can yield insight into the mechanical and rheological properties of crustal deformation associated with transform tectonics. In addition to regional continuous GPS stations, this study assembles results from campaign GPS networks in Syria, Lebanon, and Jordan spanning more than a decade. 1-sigma uncertainties on velocities range from less than 0.4 mm/yr (continuous stations and older GPS survey sites) to about 1.0 mm/yr (newer survey sites). Analyses using elastic block models suggest slip rates of 4.0 - 5.0 mm/yr along the southern and central DSF and slip rates of 2.0 - 3.0 mm/yr along the northern DSF, and fault locking depths also vary along strike of the transform. Furthermore, the spatial distribution of GPS observations permits analyzing residual strains within the adjacent plates, after plate boundary strain is removed. A key observation is horizontal stretching within the Sinai plate, which may be related to pull by the subducted slab of the Sinai plate. Within the Arabian plate, areas of horizontal stretching generally correlate with locations of Quaternary volcanism.

Quantifying surface water runoff from Wadi Arogut towards the Dead Sea

NASA Astrophysics Data System (ADS)

Geyer, Stefan; Khayat, Saed; Marei, Amer

2015-04-01

The surrounded area of the Dead Sea, especially the west side suffers from many hydrological problems. While the Dead Sea level drop considered a major problem that affect the quality of the surrounded freshwater resources, a lot of the surface water flood from the adjacent Wadi are lost through direct run off without any exploitation. Therefore, it is necessary to maintain a type of balance between surface water exploitation through the Wadi and at the same time allow a sufficient amount of flow to the Dead Sea to ensure its sustainability. In this study, we choose one of the larger tributaries in the western side of the Dead Sea basin. The stream was modelled for runoff response to different rainfall amount and climate conditions (dry, normal, and wet seasons) which were chosen from the rainy seasons in the previous 30 years. Finally, the amount of surface water contribution from each of the three seasons of the Dead Sea was quantified. The outcome of the model shows the results from the normal rainy season, which is frequently reoccurs and common in the region. The model data show that such events normally contribute with about 18-22 MCM annually to the Dead Sea. The problem is with the recurrence of dry season such as 2005/2006, by which the amount of the surface water decrease and consequently has adverse effect on the Dead Sea. However, the presence of less frequent thunder storm season such as that one in 1991/1992 has also a positive effect on the Dead Sea level. In the rainy season 1991/1992 there was a higher amount of rainfall over the study area that reaches around 155 MCM. Despite the presence of this high amount most of the recharge lost to the ground as groundwater recharge. The high amount of rain increases the amount of inundated surface water out of the Wadi banks and covers more surfaces all over the study area, which in role promote more water loss to the ground. That is why the total loss (rather than surface runoff) was much higher (77%). Moreover, 50% less precipitation in 2006 decrease the Dead Sea five metres within five years, and 60% 1992 increase of precipitation raise the water level two metre only for two to three next years. How can we balance the groundwater needs and the Dead Sea survival with those 40% surface water? By no mean: preventing the Dead Sea decline by increasing runoff will not only preventing the fresh water deterioration, but also it will be in the account of groundwater recharge in the surrounding aquifers of the Dead Sea. These conclusions suggest strongly the need of an integrated groundwater model, in order to quantify all scenarios.

50 CFR 222.310 - Permit authority for designated agents and employees of specified Federal and state agencies.

Code of Federal Regulations, 2010 CFR

2010-10-01

... stranded endangered sea turtles, and to salvage, collect data from, and dispose of, dead carcasses of... member of any endangered species of sea turtle is found stranded or dead in the marine environment, any... taking is necessary to aid a stranded sea turtle, or dispose of or salvage a dead sea turtle, or collect...

50 CFR 222.310 - Permit authority for designated agents and employees of specified Federal and state agencies.

Code of Federal Regulations, 2011 CFR

2011-10-01

... stranded endangered sea turtles, and to salvage, collect data from, and dispose of, dead carcasses of... member of any endangered species of sea turtle is found stranded or dead in the marine environment, any... taking is necessary to aid a stranded sea turtle, or dispose of or salvage a dead sea turtle, or collect...

Assessment of sea lamprey (Petromyzon marinus) predation by recovery of dead lake trout (Salvelinus namaycush) from Lake Ontario, 1982-85

USGS Publications Warehouse

Bergstedt, Roger A.; Schneider, Clifford P.

1988-01-01

During 1982-85, 89 dead lake trout (Salvelinus namaycush) were recovered with bottom trawls in U.S. waters of Lake Ontario: 28 incidentally during four annual fish-stock assessment surveys and 61 during fall surveys for dead fish. During the assessment surveys, no dead lake trout were recovered in April-June, one was recovered in August, and 27 were recovered in October or November, implying that most mortality from causes other than fishing occurred in the fall. The estimated numbers of dead lake trout between the 30- and 100-m depth contours in U.S. waters ranged from 16 000 (0.08 carcass/ha) in 1983 to 94 000 (0.46 carcass/ha) in 1982. Of 76 carcasses fresh enough to enable recognition of sea lamprey (Petromyzon marinus) wounds, 75 bore fresh wounds. Assuming that sea lamprey wounding rates on dead fish were the same as on live ones of the same length range (430-740 mm), the probability of 75 of the 76 dead lake trout bearing sea lamprey wounds was 3.5 x 10-63 if death was independent of sea lamprey attack, thus strongly implicating sea lampreys as the primary cause of death of fish in the sample. The recovery of only one unwounded dead lake trout also suggested that natural mortality from causes other than sea lamprey attactks is negligible.

77 FR 36329 - Culturally Significant Objects Imported for Exhibition Determinations: “Dead Sea Scrolls & The...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-18

... DEPARTMENT OF STATE [Public Notice 7923] Culturally Significant Objects Imported for Exhibition Determinations: ``Dead Sea Scrolls & The Bible Ancient Artifacts-- Timeless Treasures'' SUMMARY: Notice is hereby... objects to be included in the exhibition ``Dead Sea Scrolls & The Bible Ancient Artifacts--Timeless...

Fracture patterns of the drainage basin of Wadi Dahab in relation to tectonic-landscape evolution of the Gulf of Aqaba - Dead Sea transform fault

NASA Astrophysics Data System (ADS)

Shalaby, Ahmed

2017-10-01

Crustal rifting of the Arabian-Nubian Shield and formation of the Afro-Arabian rifts since the Miocene resulted in uplifting and subsequent terrain evolution of Sinai landscapes; including drainage systems and fault scarps. Geomorphic evolution of these landscapes in relation to tectonic evolution of the Afro-Arabian rifts is the prime target of this study. The fracture patterns and landscape evolution of the Wadi Dahab drainage basin (WDDB), in which its landscape is modeled by the tectonic evolution of the Gulf of Aqaba-Dead Sea transform fault, are investigated as a case study of landscape modifications of tectonically-controlled drainage systems. The early developed drainage system of the WDDB was achieved when the Sinai terrain subaerially emerged in post Eocene and initiation of the Afro-Arabian rifts in the Oligo-Miocene. Conjugate shear fractures, parallel to trends of the Afro-Arabian rifts, are synthesized with tensional fracture arrays to adapt some of inland basins, which represent the early destination of the Sinai drainage systems as paleolakes trapping alluvial sediments. Once the Gulf of Aqaba rift basin attains its deeps through sinistral movements on the Gulf of Aqaba-Dead Sea transform fault in the Pleistocene and the consequent rise of the Southern Sinai mountainous peaks, relief potential energy is significantly maintained through time so that it forced the Pleistocene runoffs to flow via drainage systems externally into the Gulf of Aqaba. Hence the older alluvial sediments are (1) carved within the paleolakes by a new generation of drainage systems; followed up through an erosional surface by sandy- to silty-based younger alluvium; and (2) brought on footslopes of fault scarps reviving the early developed scarps and inselbergs. These features argue for crustal uplifting of Sinai landscapes syn-rifting of the Gulf of Aqaba rift basin. Oblique orientation of the Red Sea-Gulf of Suez rift relative to the WNW-trending Precambrian Najd faults; and extrusion of volcanic rocks in directions parallel to the rift boundaries geometrically suggest rifting on tensional fractures that mutually bridge the Najd fault-related shear fractures. These aspects might envisage reactivation of the preexisting Precambrian fracture patterns in the Arabian-Nubian shield by the Oligo-Miocene to Pleistocene rift-controlled stress field.

50 CFR 222.310 - Permit authority for designated agents and employees of specified Federal and state agencies.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., to aid stranded endangered sea turtles, and to salvage, collect data from, and dispose of, dead.... (b) If any member of any endangered species of sea turtle is found stranded or dead in the marine... such taking is necessary to aid a stranded sea turtle, or dispose of or salvage a dead sea turtle, or...

50 CFR 222.310 - Permit authority for designated agents and employees of specified Federal and state agencies.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., to aid stranded endangered sea turtles, and to salvage, collect data from, and dispose of, dead.... (b) If any member of any endangered species of sea turtle is found stranded or dead in the marine... such taking is necessary to aid a stranded sea turtle, or dispose of or salvage a dead sea turtle, or...

50 CFR 222.310 - Permit authority for designated agents and employees of specified Federal and state agencies.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., to aid stranded endangered sea turtles, and to salvage, collect data from, and dispose of, dead.... (b) If any member of any endangered species of sea turtle is found stranded or dead in the marine... such taking is necessary to aid a stranded sea turtle, or dispose of or salvage a dead sea turtle, or...

Spatio-temporal development of sinkholes on the eastern shore of the Dead Sea

NASA Astrophysics Data System (ADS)

Holohan, Eoghan; Saberi, Leila; Al-Halbouni, Djamil; Sawarieh, Ali; Closson, Damien; Alrshdan, Hussam; Walter, Thomas; Dahm, Torsten

2017-04-01

The ongoing, largely anthropogenically-forced decline of the Dead Sea is associated with the most prolific development of sinkholes worldwide. The fall in hydrological base level since the 1960s is thought to enable relatively fresh ground waters to dissolve underground salt deposits that were previously in equilibrium with hypersaline Dead Sea brine. Sinkhole development in response to this dissolution began in the 1980s and is still ongoing; it represents a significant geohazard in the Dead Sea region. We present new research undertaken within the Dead Sea Research Venue (DESERVE) on the spatio-temporal evolution of the main sinkhole-affected site on the Eastern shore of the Dead Sea, at Ghor Al-Haditha in Jordan. Our data set includes optical satellite imagery, aerial survey photographs and drone-based photogrammetric surveys with high spatial (< 1 m2 - 0.05 m per pixel) and temporal (decadal from 1970-2010, annual from 2004-2016) resolution. These enable new quantitative insights into this, the largest of all the Dead Sea sinkhole sites. Our analysis shows that there are now over 800 sinkholes at Ghor al-Haditha. Sinkholes initiated as spatially distinct clusters in the late 1980's to early 1990s. While some clusters have since become inactive, most have expanded and merged with time. New clusters have also developed, mainly in the more recently exposed north of the area. With the retreat of the Dead Sea, the roughly coastline-parallel zone of sinkhole formation has expanded unevenly but systematically seawards. Such a seaward migration of sinkhole formation is predicted from hydrogeological theory, but as yet not consistently observed elsewhere at the Dead Sea. The rate of sinkhole formation at Ghor Haditha accelerated markedly during the late 2000s to a peak of about 100 per year in 2009. Similar accelerations are observed on the western shore, but differ in timing. The rate of sinkhole formation on the Eastern shore has since declined to about 50 per year. Such differences in the overall spatio-temporal evolution of sinkholes on the eastern and western shores of the Dead Sea likely highlights the important role of local hydrogeological conditions and processes in governing sinkhole development.

The Northern end of the Dead Sea Basin: Geometry from reflection seismic evidence

USGS Publications Warehouse

Al-Zoubi, A. S.; Heinrichs, T.; Qabbani, I.; ten Brink, Uri S.

2007-01-01

Recently released reflection seismic lines from the Eastern side of the Jordan River north of the Dead Sea were interpreted by using borehole data and incorporated with the previously published seismic lines of the eastern side of the Jordan River. For the first time, the lines from the eastern side of the Jordan River were combined with the published reflection seismic lines from the western side of the Jordan River. In the complete cross sections, the inner deep basin is strongly asymmetric toward the Jericho Fault supporting the interpretation of this segment of the fault as the long-lived and presently active part of the Dead Sea Transform. There is no indication for a shift of the depocenter toward a hypothetical eastern major fault with time, as recently suggested. Rather, the north-eastern margin of the deep basin takes the form of a large flexure, modestly faulted. In the N-S-section along its depocenter, the floor of the basin at its northern end appears to deepen continuously by roughly 0.5??km over 10??km distance, without evidence of a transverse fault. The asymmetric and gently-dipping shape of the basin can be explained by models in which the basin is located outside the area of overlap between en-echelon strike-slip faults. ?? 2007 Elsevier B.V. All rights reserved.

Foehn-induced effects on local dust pollution, frontal clouds and solar radiation in the Dead Sea valley

NASA Astrophysics Data System (ADS)

Kishcha, Pavel; Starobinets, Boris; Savir, Amit; Alpert, Pinhas; Kaplan, Michael

2018-06-01

Despite the long history of investigation of foehn phenomena, there are few studies of the influence of foehn winds on air pollution and none in the Dead Sea valley. For the first time the foehn phenomenon and its effects on local dust pollution, frontal cloudiness and surface solar radiation were analyzed in the Dead Sea valley, as it occurred on 22 March 2013. This was carried out using both numerical simulations and observations. The foehn winds intensified local dust emissions, while the foehn-induced temperature inversion trapped dust particles beneath this inversion. These two factors caused extreme surface dust concentration in the western Dead Sea valley. The dust pollution was transported by west winds eastward, to the central Dead Sea valley, where the speed of these winds sharply decreased. The transported dust was captured by the ascending airflow contributing to the maximum aerosol optical depth (AOD) over the central Dead Sea valley. On the day under study, the maximum surface dust concentration did not coincide with the maximum AOD: this being one of the specific effects of the foehn phenomenon on dust pollution in the Dead Sea valley. Radar data showed a passage of frontal cloudiness through the area of the Dead Sea valley leading to a sharp drop in noon solar radiation. The descending airflow over the downwind side of the Judean Mountains led to the formation of a cloud-free band followed by only the partial recovery of solar radiation because of the extreme dust pollution caused by foehn winds.

Dead sea asphalts: historical aspects

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

Nissenbaum, A.

1978-05-01

Asphalts are present in the Dead Sea basin in three forms: (1) huge blocks, up to 100 tons in weight, composed of extremely pure (>99.99%) solid asphalt occasionally found floating on the lake, (2) veins, seepages, and cavity and fissure fillings in Lower Cretaceous to Holocene rocks, and (3) ozocerite veins on the eastern shore of the lake. Dead Sea asphalts probably have been documented over a longer period of time than any other hydrocarbon deposit--from antiquity to the 19th century. Major uses of asphalt from the Dead Sea have been as an ingredient in the embalming process, for medicinalmore » purposes, for fumigation, and for agriculture. The first known war for control of a hydrocarbon deposit was in the Dead Sea area in 312 B.C. between the Seleucid Syrians and the Nabatean Arabs who lived around the lake. Surface manifestations of asphalt are linked closely to tectonic activity. In the lake itself, the asphalt is associated with diapirs During certain historic periods, tectonic and diapiric activity caused frequent liberation to the Dead Sea surface of semiliquid asphalt associated with large amounts of hydrogen sulfide gas. When the tectonic activity was attenuated, as in the 19th and 20th centuries, the rate of asphalt seepage to the bottom sediments of the Dead Sea was much slower and the asphalt solidified on the lake bottom. The release of asphalt to the surface became much more sporadic, and may have resulted in part from earthquakes. Thus, future asphalt prospecting in the Dead Sea area should be conducted along the boundaries of diapirs or their associated faults.« less

76 FR 63341 - Culturally Significant Objects Imported for Exhibition Determinations: “The Dead Sea Scrolls...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-12

... DEPARTMENT OF STATE [Public Notice 7644] Culturally Significant Objects Imported for Exhibition Determinations: ``The Dead Sea Scrolls: Life and Faith in Biblical Times'' SUMMARY: Notice is hereby given of the... exhibition ``The Dead Sea Scrolls: Life and Faith in Biblical Times'' imported from abroad for temporary...

75 FR 7536 - Culturally Significant Objects Imported for Exhibition Determinations: “The Dead Sea Scrolls...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-19

... DEPARTMENT OF STATE [Public Notice 6898] Culturally Significant Objects Imported for Exhibition Determinations: ``The Dead Sea Scrolls: Words That Changed the World'' Summary: Notice is hereby given of the... included in the exhibition ``The Dead Sea Scrolls: Words That Changed the World,'' imported from abroad for...

The Dead Sea Mud and Salt: A Review of Its Characterization, Contaminants, and Beneficial Effects

NASA Astrophysics Data System (ADS)

Bawab, Abeer Al; Bozeya, Ayat; Abu-Mallouh, Saida; Abu Irmaileh, Basha'er; Daqour, Ismail; Abu-Zurayk, Rund A.

2018-02-01

The Dead Sea has been known for its therapeutic and cosmetic properties. The unique climatic conditions in the Dead Sea area make it a renowned site worldwide for the field of climatotherapy, which is a natural approach for the provision of medications for many human diseases including unusual exclusive salt composition of the water, a special natural mud, thermal mineral springs, solar irradiation, oxygen-rich and bromine-rich haze. This review focuses on the physical, chemical, and biological characteristics of the Dead Sea mud and salts, in addition to their contaminants, allowing this review to serve as a guide to interested researchers to their risks and the importance of treatment. Beneficial effects of Dead Sea mud and salts are discussed in terms of therapy and cosmetics. Additional benefits of both Dead Sea mud and salts are also discussed, such as antimicrobial action of the mud in relation to its therapeutic properties, and the potency of mud and salts to be a good medium for the growth of a halophilic unicellular algae, used for the commercial production of β-carotene Dunaliella.

Crustal structure of the southern Dead Sea basin derived from project DESIRE wide-angle seismic data

NASA Astrophysics Data System (ADS)

Mechie, J.; Abu-Ayyash, K.; Ben-Avraham, Z.; El-Kelani, R.; Qabbani, I.; Weber, M.

2009-07-01

As part of the DEad Sea Integrated REsearch project (DESIRE) a 235 km long seismic wide-angle reflection/refraction (WRR) profile was completed in spring 2006 across the Dead Sea Transform (DST) in the region of the southern Dead Sea basin (DSB). The DST with a total of about 107 km multi-stage left-lateral shear since about 18 Ma ago, accommodates the movement between the Arabian and African plates. It connects the spreading centre in the Red Sea with the Taurus collision zone in Turkey over a length of about 1100 km. With a sedimentary infill of about 10 km in places, the southern DSB is the largest pull-apart basin along the DST and one of the largest pull-apart basins on Earth. The WRR measurements comprised 11 shots recorded by 200 three-component and 400 one-component instruments spaced 300 m to 1.2 km apart along the whole length of the E-W trending profile. Models of the P-wave velocity structure derived from the WRR data show that the sedimentary infill associated with the formation of the southern DSB is about 8.5 km thick beneath the profile. With around an additional 2 km of older sediments, the depth to the seismic basement beneath the southern DSB is about 11 km below sea level beneath the profile. Seismic refraction data from an earlier experiment suggest that the seismic basement continues to deepen to a maximum depth of about 14 km, about 10 km south of the DESIRE profile. In contrast, the interfaces below about 20 km depth, including the top of the lower crust and the Moho, probably show less than 3 km variation in depth beneath the profile as it crosses the southern DSB. Thus the Dead Sea pull-apart basin may be essentially an upper crustal feature with upper crustal extension associated with the left-lateral motion along the DST. The boundary between the upper and lower crust at about 20 km depth might act as a decoupling zone. Below this boundary the two plates move past each other in what is essentially a shearing motion. Thermo-mechanical modelling of the DSB supports such a scenario. As the DESIRE seismic profile crosses the DST about 100 km north of where the DESERT seismic profile crosses the DST, it has been possible to construct a crustal cross-section of the region before the 107 km left-lateral shear on the DST occurred.

Foehn-induced effects on dust pollution, frontal clouds and solar radiation in the Dead Sea valley

NASA Astrophysics Data System (ADS)

Kishcha, Pavel; Starobinets, Boris; Alpert, Pinhas; Kaplan, Michael

2017-04-01

The significant drying up of the Dead Sea over the past 40 years has led to an increase in an exposed area contributing to local dust pollution. Measurements show that, sometimes, in the Dead Sea valley, dust pollution can reach extreme concentrations up to several thousands of micrograms per cubic meters. Our analysis of a meteorological situation shows that a foehn phenomenon can be a causal factor for the aforementioned extreme local dust concentration. This foehn phenomenon creates strong warm and dry winds, which are accompanied by air turbulence and temperature inversion. In our study, foehn-induced effects on dust pollution, frontal clouds and solar radiation were analyzed over the Judean Mountains ( 1000 m) and over the Dead Sea valley (-420 m), using high-resolution numerical simulations and in-situ observations at meteorological stations located across the mountain ridge. An extreme dust episode occurring on March 22, 2013, was analyzed, which was characterized by measured surface dust concentrations of up to 7000 µg m-3 in the Dead Sea valley. We simulated this foehn phenomenon with the 3-km resolution COSMO-ART model. Our analysis has shown that the foehn phenomenon could be observed even over the relatively low Judean Mountains. This analysis was based on various meteorological, pyranometer, radar, and aerosol measurements together with high-resolution model data. In the Dead Sea valley, the maximum aerosol optical depth (AOD) did not coincide with the maximum surface dust concentration. This lack of coincidence indicates difficulties in using satellite-based AOD for initializing dust concentration within numerical forecast systems over this region with complex terrain. In the western Dead Sea valley, strong foehn winds of over 20 m/s were accompanied by maximal air turbulence leading to maximal local dust emissions. Thus, the model showed that, by creating significant turbulence, the foehn phenomenon intensified the saltation (bombardment) mechanism of local dust generation in the western Dead Sea valley. In addition, the foehn-induced pronounced temperature inversion trapped dust particles beneath this inversion. These two factors caused the measured extreme surface dust concentration in the Dead Sea valley on the specified day. Radar data on March 22 showed a passage of multi-layer frontal cloudiness through the area of the Dead Sea valley leading to a sharp drop in noon solar radiation. The strong descending airflow over the downwind side of the Judean Mountains significantly influenced the frontal cloudiness leading to the formation of a cloud-free band over the Dead Sea valley.

Active Thrusting Offshore Mount Lebanon: Source of the Tsunamigenic A.D. 551 Beirut-Tripoli Earthquake

NASA Astrophysics Data System (ADS)

Tapponnier, P.; Elias, A.; Singh, S.; King, G.; Briais, A.; Daeron, M.; Carton, H.; Sursock, A.; Jacques, E.; Jomaa, R.; Klinger, Y.

2007-12-01

On July 9, AD 551, a large earthquake, followed by a tsunami destroyed most of the coastal cities of Phoenicia (modern-day Lebanon). This was arguably one of the most devastating historical submarine earthquakes in the eastern Mediterranean. Geophysical data from the Shalimar survey unveils the source of this Mw=7.5 event: rupture of the offshore, hitherto unknown, 100?150 km-long, active, east-dipping Mount Lebanon Thrust (MLT). Deep-towed sonar swaths along the base of prominent bathymetric escarpments reveal fresh, west facing seismic scarps that cut the sediment-smoothed seafloor. The MLT trace comes closest (~ 8 km) to the coast between Beirut and Enfeh, where as 13 radiocarbon-calibrated ages indicate, a shoreline-fringing Vermetid bench suddenly emerged by ~ 80 cm in the 6th century AD. At Tabarja, the regular vertical separation (~ 1 m) of higher fossil benches, suggests uplift by 3 more comparable-size earthquakes since the Holocene sea-level reached a maximum ca. 7-6 ka, implying a 1500?1750 yr recurrence time. Unabated thrusting on the MLT likely orchestrated the growth of Mt. Lebanon since the late Miocene. The newly discovered MLT has been the missing piece in the Dead Sea Transform and eastern Mediterranean tectonic scheme. Identifying the source of the AD 551 event thus ends a complete reassessment of the sources of the major historical earthquakes on the various faults of the Lebanese Restraining Bend of the Levant Fault System (or Dead Sea Transform).

Active Thrusting Offshore Mount Lebanon: Source of the Tsunamigenic A.D. 551 Beirut-Tripoli Earthquake

NASA Astrophysics Data System (ADS)

Tapponnier, P.; Elias, A.; Singh, S.; King, G.; Briais, A.; Daeron, M.; Carton, H.; Sursock, A.; Jacques, E.; Jomaa, R.; Klinger, Y.

2004-12-01

On July 9, AD 551, a large earthquake, followed by a tsunami destroyed most of the coastal cities of Phoenicia (modern-day Lebanon). This was arguably one of the most devastating historical submarine earthquakes in the eastern Mediterranean. Geophysical data from the Shalimar survey unveils the source of this Mw=7.5 event: rupture of the offshore, hitherto unknown, 100?150 km-long, active, east-dipping Mount Lebanon Thrust (MLT). Deep-towed sonar swaths along the base of prominent bathymetric escarpments reveal fresh, west facing seismic scarps that cut the sediment-smoothed seafloor. The MLT trace comes closest (~ 8 km) to the coast between Beirut and Enfeh, where as 13 radiocarbon-calibrated ages indicate, a shoreline-fringing Vermetid bench suddenly emerged by ~ 80 cm in the 6th century AD. At Tabarja, the regular vertical separation (~ 1 m) of higher fossil benches, suggests uplift by 3 more comparable-size earthquakes since the Holocene sea-level reached a maximum ca. 7-6 ka, implying a 1500?1750 yr recurrence time. Unabated thrusting on the MLT likely orchestrated the growth of Mt. Lebanon since the late Miocene. The newly discovered MLT has been the missing piece in the Dead Sea Transform and eastern Mediterranean tectonic scheme. Identifying the source of the AD 551 event thus ends a complete reassessment of the sources of the major historical earthquakes on the various faults of the Lebanese Restraining Bend of the Levant Fault System (or Dead Sea Transform).

Microbial and Chemical Characterization of Underwater Fresh Water Springs in the Dead Sea

PubMed Central

Ionescu, Danny; Siebert, Christian; Polerecky, Lubos; Munwes, Yaniv Y.; Lott, Christian; Häusler, Stefan; Bižić-Ionescu, Mina; Quast, Christian; Peplies, Jörg; Glöckner, Frank Oliver; Ramette, Alban; Rödiger, Tino; Dittmar, Thorsten; Oren, Aharon; Geyer, Stefan; Stärk, Hans-Joachim; Sauter, Martin; Licha, Tobias; Laronne, Jonathan B.; de Beer, Dirk

2012-01-01

Due to its extreme salinity and high Mg concentration the Dead Sea is characterized by a very low density of cells most of which are Archaea. We discovered several underwater fresh to brackish water springs in the Dead Sea harboring dense microbial communities. We provide the first characterization of these communities, discuss their possible origin, hydrochemical environment, energetic resources and the putative biogeochemical pathways they are mediating. Pyrosequencing of the 16S rRNA gene and community fingerprinting methods showed that the spring community originates from the Dead Sea sediments and not from the aquifer. Furthermore, it suggested that there is a dense Archaeal community in the shoreline pore water of the lake. Sequences of bacterial sulfate reducers, nitrifiers iron oxidizers and iron reducers were identified as well. Analysis of white and green biofilms suggested that sulfide oxidation through chemolitotrophy and phototrophy is highly significant. Hyperspectral analysis showed a tight association between abundant green sulfur bacteria and cyanobacteria in the green biofilms. Together, our findings show that the Dead Sea floor harbors diverse microbial communities, part of which is not known from other hypersaline environments. Analysis of the water’s chemistry shows evidence of microbial activity along the path and suggests that the springs supply nitrogen, phosphorus and organic matter to the microbial communities in the Dead Sea. The underwater springs are a newly recognized water source for the Dead Sea. Their input of microorganisms and nutrients needs to be considered in the assessment of possible impact of dilution events of the lake surface waters, such as those that will occur in the future due to the intended establishment of the Red Sea−Dead Sea water conduit. PMID:22679498

Diurnal Course of Evaporation From the Dead Sea in Summer: A Distinct Double Peak Induced by Solar Radiation and Night Sea Breeze

NASA Astrophysics Data System (ADS)

Lensky, N. G.; Lensky, I. M.; Peretz, A.; Gertman, I.; Tanny, J.; Assouline, S.

2018-01-01

Partitioning between the relative effects of the radiative and aerodynamic components of the atmospheric forcing on evaporation is challenging since diurnal distributions of wind speed and solar radiation typically overlap. The Dead Sea is located about a 100 km off the Eastern Mediterranean coast, where and the Mediterranean Sea breeze front reaches it after sunset. Therefore, in the Dead Sea the peaks of solar radiation and wind speed diurnal cycles in the Dead Sea are distinctly separated in time, offering a unique opportunity to distinguish between their relative impacts on evaporation. We present mid-summer eddy covariance and meteorological measurements of evaporation rate and surface energy fluxes over the Dead Sea. The evaporation rate is characterized by a clear diurnal cycle with a daytime peak, few hours after solar radiation peak, and a nighttime peak coincident with wind speed peak. Evaporation rate is minimum during sunrise and sunset. Measurements of evaporation rate from two other water bodies that are closer to the Mediterranean coast, Eshkol Reservoir, and Lake Kinneret, present a single afternoon peak, synchronous with the sea breeze. The inland diurnal evaporation rate cycle varies with the distance from the Mediterranean coast, following the propagation of sea breeze front: near the coast, wind speed, and radiation peaks are close and consequently a single daily evaporation peak appears in the afternoon; at the Dead Sea, about a 100 km inland, the sea breeze front arrives at sunset, resulting in a diurnal evaporation cycle characterized by a distinct double peak.

The Dead Sea, The Lake and Its Setting

NASA Astrophysics Data System (ADS)

Brink, Uri ten

I cannot think of a subject more befitting the description of interdisciplinary research with societal relevance than the study of the Dead Sea, a terminal lake of the Jordan River in Israel and Jordan. The scientific study of the Dead Sea is intimately connected with politics, religion, archeology, economic development, tourism, and environmental change.The Dead Sea is a relatively closed geologic and limnologic system with drastic physical changes often occurring on human timescales and with a long human history to observe these changes. Research in this unique area covers diverse aspects such as active subsidence and deformation along strike-slip faults; vertical stratification and stability of the water column; physical properties of extremely saline and dense (1234 kg/m3) water; spontaneous precipitation of minerals in an oversaturated environment; origin of the unusual chemical composition of the brine; existence of life in extreme environments; use of lake level fluctuations as a paleoclimatic indicator; and effects on the environment of human intervention versus natural climatic variability. Although the Dead Sea covers a small area on a global scale, it is nevertheless one of the largest natural laboratories for these types of research on Earth. These reasons make the Dead Sea a fascinating topic for the curious mind.

Simulation of the Aerosol-Atmosphere Interaction in the Dead Sea Area with COSMO-ART

NASA Astrophysics Data System (ADS)

Vogel, Bernhard; Bangert, Max; Kottmeier, Christoph; Rieger, Daniel; Schad, Tobias; Vogel, Heike

2014-05-01

The Dead Sea is a unique environment located in the Dead Sea Rift Valley. The fault system of the Dead Sea Rift Valley marks the political borders between Israel, Jordan, and Palestine. The Dead Sea region and the ambient Eastern Mediterranean coastal zone provide a natural laboratory for studying atmospheric processes ranging from the smallest scale of cloud processes to regional weather and climate. The virtual institute DESERVE is designed as a cross-disciplinary and cooperative international project of the Helmholtz Centers KIT, GFZ, and UFZ with well-established partners in Israel, Jordan and Palestine. One main focus of one of the work packages is the role of aerosols in modifying clouds and precipitation and in developing the Dead Sea haze layer as one of the most intriguing questions. The haze influences visibility, solar radiation, and evaporation and may even affect economy and health. We applied the online coupled model system COSMO-ART, which is able to treat the feedback processes between aerosol, radiation, and cloud formation, for a case study above the Dead Sea and adjacent regions. Natural aerosol like mineral dust and sea salt as well as anthropogenic primary and secondary aerosol is taken into account. Some of the observed features like the vertical double structure of the haze layer are already covered by the simulation. We found that absorbing aerosol like mineral dust causes a temperature increase in parts of the model domain. In other areas a decrease in temperature due to cirrus clouds modified by elevated dust layers is simulated.

The ICDP Dead Sea deep drill cores: records of climate change and tectonics in the Levant

NASA Astrophysics Data System (ADS)

Goldstein, S. L.; Stein, M.; Ben-Avraham, Z.; Agnon, A.; Ariztegui, D.; Brauer, A.; Haug, G. H.; Ito, E.; Kitagawa, H.; Torfstein, A.

2012-12-01

The Dead Sea drainage basin sits at the boundary of the Mediterranean and the Saharan climate zones, and the basin is formed by the Dead Sea transform fault. The ICDP-funded Dead Sea Deep Drilling Project recovered the longest and most complete paleo-environmental and paleo-seismic record in the Middle East, drilling holes of ~450 and ~350 meters in deep (~300 m below the lake level) and shallow sites (~3 m), respectively, and. The sediments record the evolving environmental conditions (e.g. droughts, rains, floods, dust-storms), as well as tectonics (earthquake layers). The core can be dated using 14C on organic materials, U-Th on inorganic aragonite, stable isotopes, and layer counting. They were opened, described, and XRF-scanned during June to November 2011, the first sampling party took place in July 2012, and study is now underway. Some important conclusions can already be drawn. The stratigraphy reflects the climate conditions. During wet climate intervals the lithology is typically varve-like laminated aragonite and detritus (aad), reflecting summer and winter seasons, respectively, and sequences of mud. Gypsum layers reflect more arid climate, and salt (halite) indicates extreme aridity. The Dead Sea expands during glacials, and the portion of the core that corresponds to the last glacial Lisan Formation above the shoreline is easily recognized in the core based on the common lithological sequence, and this allows us to infer a broad scale age model. Interglacials show all the lithologic facies (aad, mud, gypsum, salt), reflecting extreme climate variability, while glacials contain the aad, mud, and gypsum but lack salt layers. Thus we estimate that the deep site hole extends into MIS 7 (to ~200,000 years). Thin (up to several cm thick) seismic layers occur throughout the core, but thick (up to several meters) landslide deposits only occur during glacial intervals. The most dramatic discovery is evidence of an extreme dry interval during MIS 5 at the deep site. There is a ~40 cm thick interval of partly rounded pebbles in the core at ~235 m below the lake floor. It is the only clean pebbly unit in the core, and resembles a beach deposit. Below the layer there is ~45 meters of mainly salt. These observations indicate a severe dry interval during MIS 5. This observation has implications for the Middle East today, where the Dead Sea level is dropping at rates >1m/year, as all the countries in the area are using all the runoff. GCM models indicate a more arid future in the region. The core shows that the runoff nearly stopped during the last interglacial without human intervention. Dating is underway to constrain the timing of the extreme drydown.

Quality of life at the Dead Sea region: the lower the better? An observational study.

PubMed

Avriel, Avital; Fuchs, Lior; Plakht, Ygal; Cicurel, Assi; Apfelbaum, Armando; Satran, Robert; Friger, Michael; Dartava, Dimitry; Sukenik, Shaul

2011-05-27

The Dead Sea region, the lowest in the world at 410 meters below sea level, is considered a potent climatotherapy center for the treatment of different chronic diseases. To assess the prevalence of chronic diseases and the quality of life of residents of the Dead Sea region compared with residents of the Ramat Negev region, which has a similar climate, but is situated 600 meters above sea level. An observational study based on a self-administered questionnaire. Data were collected from kibbutz (communal settlement) members in both regions. Residents of the Dead Sea were the study group and of Ramat Negev were the control group. We compared demographic characteristics, the prevalence of different chronic diseases and health-related quality of life (HRQOL) using the SF-36 questionnaire. There was a higher prevalence of skin nevi and non-inflammatory rheumatic diseases (NIRD) among Dead Sea residents, but they had significantly higher HRQOL mean scores in general health (68.7 ± 21 vs. 64.4 ± 22, p = 0.023) and vitality (64.7 ± 17.9 vs. 59.6 ± 17.3, p = 0.001), as well as significantly higher summary scores: physical component score (80.7 ± 18.2 vs. 78 ± 18.6, p = 0.042), and mental component score (79 ± 16.4 vs. 77.2 ± 15, p = 0.02). These results did not change after adjusting for social-demographic characteristics, health-related habits, and chronic diseases. No significant difference between the groups was found in the prevalence of most chronic diseases, except for higher rates of skin nevi and NIRD among Dead Sea residents. HRQOL was significantly higher among Dead Sea residents, both healthy or with chronic disease.

Seismotectonics and crustal stress across the northern Arabian plate

NASA Astrophysics Data System (ADS)

yassminh, R.; Gomez, F. G.; Sandvol, E. A.; Ghalib, H. A.; Daoud, M.

2013-12-01

The region encompassing the collision of northern Arabia with Eurasia is a tectonically heterogeneous region of distributed deformation. The northern Arabia plate is bounded to the west by the subducting Sinai plate and the left-lateral Dead Sea transform. This complexity suggests that there are, multiple competing processes that may influence regional tectonics in northern Arabia and adjacent areas. Earthquake mechanisms provide insight into crustal kinematics and stress; however, reliable determination of earthquake source parameters can be challenging in a complex geological region, such as the continental collision zone between the Arabian and Eurasian plates. The goal of this study is to investigate spatial patterns of the crustal stress in the northern Arabian plate and surrounding area. The focal mechanisms used in this study are based on (1) first-motion polarities for earthquakes recorded by Syrian earthquake center during 2000-2011, and (2) regional moment tensors from broadband seismic data, from Turkey and Iraq. First motion focal mechanisms were assigned quality classifications based on the variation of both nodal planes. Regional moment tensor analysis can be significantly influenced by seismic velocity structure; thus, we have divided the study area into regions based on tectonic units. For each region, a specific velocity model is defined using waveform-modeling technique prior to the regional moment tensor inversion. The resulting focal mechanisms, combined with other previously published focal mechanisms for the study area, provide a basis for stress inversion analysis. The resulting deviatoric stress tensors show the spatial distribution of the maximum horizontal stress varies from NW-SE along the Dead Sea Fault to the N-S toward the east. We interpret this to reflect the eastward change from the transform to collision processes in northern Arabia. Along the Dead Sea Fault, transposition of the sigma-1 and sigma-2 to vertical and horizontal, respectively, may relate to influences from the subducted part of the Sinai plate. This change in regional stress is also consistent with extensional strains observed from GPS velocities.

Present-Day Strain and Rotation in the Lebanese Restraining Bend of the Dead Sea Fault System Based on Analysis of GPS Velocities

NASA Astrophysics Data System (ADS)

Gomez, F.; Jaafar, R.; Abdallah, C.; Karam, G.

2012-12-01

The Lebanese Restraining Bend (LRB) is a ~200-km-long bend in the central part of the Dead Sea Fault system (DSFS). As with other large restraining bends, this part of the transform is characterized by more complicated structure than other parts. Additionally, results from recent GPS studies have documented slower velocities north of the LRB than are observed along the southern DSFS to the south. In an effort to understand how strain is transferred through the LRB, this study analyzes improved GPS velocities within the central DSFS based on new data and additional stations. Despite relatively modest rates of seismicity, the Dead Sea Fault system (DSFS) has a historically documented record of producing large and devastating earthquakes. Hence, geodetic measurements of crustal deformation may provide key constraints on processes of strain accumulation that may not be evident in instrumentally recorded seismicity. Within the LRB, the transform splays into two prominent strike-slip faults: The through-going Yammouneh fault and the Serghaya fault. The latter appears to terminate in the Anti-Lebanon Mountains. Additionally, some oblique plate motion is accommodated by thrusting along the coast of Lebanon. This study used GPS observations from survey-mode GPS sites, as well as continuous GPS stations in the region. In total, 22 GPS survey sites have been measured in Lebanon between 2002 and 2010, along with GPS data from the adjacent area. Elastic models are used for initial assessment of fault slip rates. Incorporating two major strike-slip faults, as well as an offshore thrust fault, this modeling suggests left-lateral slip rates of 3.8 mm/yr and 1.1 mm/yr for the Yammouneh and Serghaya faults, respectively. The GPS survey network has sufficient density for analyzing velocity gradients in an effort to quantify tectonic strains and rotations. The velocity gradients suggest that differential rotations play a role in accommodating some plate motion.

Challenges to estimate surface- and groundwater flow in arid regions: the Dead Sea catchment.

PubMed

Siebert, Christian; Rödiger, Tino; Mallast, Ulf; Gräbe, Agnes; Guttman, Joseph; Laronne, Jonathan B; Storz-Peretz, Yael; Greenman, Anat; Salameh, Elias; Al-Raggad, Marwan; Vachtman, Dina; Zvi, Arie Ben; Ionescu, Danny; Brenner, Asher; Merz, Ralf; Geyer, Stefan

2014-07-01

The overall aim of the this study, which was conducted within the framework of the multilateral IWRM project SUMAR, was to expand the scientific basement to quantify surface- and groundwater fluxes towards the hypersaline Dead Sea. The flux significance for the arid vicinity around the Dead Sea is decisive not only for a sustainable management in terms of water availability for future generations but also for the resilience of the unique ecosystems along its coast. Coping with different challenges interdisciplinary methods like (i) hydrogeochemical fingerprinting, (ii) satellite and airborne-based thermal remote sensing, (iii) direct measurement with gauging station in ephemeral wadis and a first multilateral gauging station at the river Jordan, (iv) hydro-bio-geochemical approach at submarine and shore springs along the Dead Sea and (v) hydro(geo)logical modelling contributed to the overall aim. As primary results, we deduce that the following: (i) Within the drainage basins of the Dead Sea, the total mean annual precipitation amounts to 300 mm a(−1) west and to 179 mm a(−1) east of the lake, respectively. (ii) The total mean annual runoff volumes from side wadis (except the Jordan River) entering the Dead Sea is approximately 58–66 × 10(6) m(3) a(−1) (western wadis: 7–15 × 10(6) m(3) a(−1); eastern wadis: 51 × 10(6) m(3) a(−1)). (iii) The modelled groundwater discharge from the upper Cretaceous aquifers in both flanks of the Dead Sea towards the lake amounts to 177 × 10(6) m(3) a(−1). (iv) An unexpected abundance of life in submarine springs exists, which in turn explains microbial moderated geo-bio-chemical processes in the Dead Sea sediments, affecting the highly variable chemical composition of on- and offshore spring waters.The results of this work show a promising enhancement of describing and modelling the Dead Sea basin as a whole. Copyright © 2014 Elsevier B.V. All rights reserved.

Last Glacial vegetation and climate change in the southern Levant

NASA Astrophysics Data System (ADS)

Miebach, Andrea; Chen, Chunzhu; Litt, Thomas

2015-04-01

Reconstructing past climatic and environmental conditions is a key task for understanding the history of modern mankind. The interaction between environmental change and migration processes of the modern Homo sapiens from its source area in Africa into Europe is still poorly understood. The principal corridor of the first human dispersal into Europe and also later migration dynamics crossed the Middle East. Therefore, the southern Levant is a key area to investigate the paleoenvironment during times of human migration. In this sense, the Last Glacial (MIS 4-2) is particularly interesting to investigate for two reasons. Firstly, secondary expansions of the modern Homo sapiens are expected to occur during this period. Secondly, there are ongoing discussions on the environmental conditions causing the prominent lake level high stand of Lake Lisan, the precursor of the Dead Sea. This high stand even culminated in the merging of Lake Lisan and Lake Kinneret (Sea of Galilee). To provide an independent proxy for paleoenvironmental reconstructions in the southern Levant during the Last Glacial, we investigated pollen assemblages of the Dead Sea/Lake Lisan and Lake Kinneret. Located at the Dead Sea Transform, the freshwater Lake Kinneret is nowadays connected via the Jordan with the hypersaline Dead Sea, which occupies Earth's lowest elevation on land. The southern Levant is a transition area of three different vegetation types. Therefore, also small changes in the climate conditions effect the vegetation and can be registered in the pollen assemblage. In contrast to the Holocene, our preliminary results suggest another vegetation pattern during the Last Glacial. The vegetation belt of the fragile Mediterranean biome did no longer exist in the vicinity of Lake Kinneret. Moreover, the vegetation was rather similar in the whole study area. A steppe vegetation with dwarf shrubs, herbs, and grasses predominated. Thermophilous elements like oaks occurred in limited amounts. The limiting factor for tree growth was precipitation. Consequently, the precipitation gradient was not as strong as today, and semiarid conditions prevailed in the southern Levant during the Last Glacial. Our study will contribute to the overall aim to reconstruct the way of modern humans to Europe and to understand the complex connection between climate and vegetation change in the Eastern Mediterranean.

Monitoring the Dead Sea Region by Multi-Parameter Stations

NASA Astrophysics Data System (ADS)

Mohsen, A.; Weber, M. H.; Kottmeier, C.; Asch, G.

2015-12-01

The Dead Sea Region is an exceptional ecosystem whose seismic activity has influenced all facets of the development, from ground water availability to human evolution. Israelis, Palestinians and Jordanians living in the Dead Sea region are exposed to severe earthquake hazard. Repeatedly large earthquakes (e.g. 1927, magnitude 6.0; (Ambraseys, 2009)) shook the whole Dead Sea region proving that earthquake hazard knows no borders and damaging seismic events can strike anytime. Combined with the high vulnerability of cities in the region and with the enormous concentration of historical values this natural hazard results in an extreme earthquake risk. Thus, an integration of earthquake parameters at all scales (size and time) and their combination with data of infrastructure are needed with the specific aim of providing a state-of-the-art seismic hazard assessment for the Dead Sea region as well as a first quantitative estimate of vulnerability and risk. A strong motivation for our research is the lack of reliable multi-parameter ground-based geophysical information on earthquakes in the Dead Sea region. The proposed set up of a number of observatories with on-line data access will enable to derive the present-day seismicity and deformation pattern in the Dead Sea region. The first multi-parameter stations were installed in Jordan, Israel and Palestine for long-time monitoring. All partners will jointly use these locations. All stations will have an open data policy, with the Deutsches GeoForschungsZentrum (GFZ, Potsdam, Germany) providing the hard and software for real-time data transmission via satellite to Germany, where all partners can access the data via standard data protocols.

Extreme Dead Sea drying event during the last interglacial from the ICDP Dead Sea Deep Drill Core

NASA Astrophysics Data System (ADS)

Goldstein, S.; Stein, M.; Ben-Avraham, Z.; Agnon, A.; Ariztegui, D.; Brauer, A.; Haug, G.; Ito, E.; Kitagawa, H.; Torfstein, A.; Yasuda, Y.

2012-04-01

The ICDP funded Dead Sea Deep Drilling Project (DSDDP) recovered the longest and most complete paleo-environmental record in the Middle East, drilling holes in a deep and a shallow site extending to ~450 meters. The Dead Sea expands during the glacials and contracts during interglacials, and the sediments are an archive of the evolving climatic conditions. During glacials the sediments comprise intervals of marl (aragonite, gypsum and detritus) and during interglacials they are salts and marls. We estimate that the deep site core spans ~200 kyr (to early MIS 7). A dramatic discovery is a ~40 cm interval of rounded pebbles at ~235 m below the lake floor, the only clean pebbly unit in the entire core. It appears to be a beach layer, near the deepest part of the Dead Sea, lying above ~35 meters of mainly salt. If it is a beach layer, it implies an almost complete dry-down of the paleo-Dead Sea. The pebble layer lies within the last interglacial interval. Our initial attempt to estimate the age of the possible dry down shows an intriguing correlation between the salt-mud stratigraphy of the Dead Sea core and the oxygen isotope record of Soreq Cave, whereby excursions to light oxygen in the speleothems correspond to periods of salt deposition. Through this comparison, we estimate that the dry down occurred during MIS 5e. The occurrence of ~35 meters of mainly salt along with the pebble layer demonstrates a severe dry interval during MIS 5. This observation has implications for the Middle East today, where the Dead Sea level is dropping as all the countries in the area use the runoff. GCM models indicate a more arid future in the region. The core shows that the runoff nearly stopped during a past warm period without human intervention.

Synoptic conditions of fine-particle transport to the last interglacial Red Sea -Dead Sea from Nd-Sr compositions of sediment cores

NASA Astrophysics Data System (ADS)

Stein, M.; Palchan, D.; Goldstein, S. L.; Almogi-Labin, A.; Tirosh, O.; Erel, Y.

2017-12-01

The last interglacial peak, Marine Isotope Stage 5e (MIS 5e), was associated with stronger northern hemisphere insolation, higher global sea levels and higher average global temperatures compared to the Holocene, and is considered as an analogue for a future warming world. In this perspective the present-day areas of the Sahara - Arabia deserts (the "desert belt") are of special interest since their margins are densely inhabited and global climate models predict enhanced aridity in these regions due to future warming. The Red Sea situated at the midst of the desert belt and the Dead Sea at the northern fringe of the desert belt comprise sensitive monitors for past hydroclimate changes in the Red Sea-Levant regions as global climate shifted from glacial to interglacial conditions. Here, we reconstruct the synoptic conditions that controlled desert dust transport to the Red Sea and the Dead Sea during MIS5e. The reconstruction is based on Nd-Sr isotopes and chemical composition of carbonate-free detritus recovered from sediment cores drilled at the deep floors of these water-bodies combined with data of contemporaneous dust storms transporting dust to the lake and sea floors. During Termination 2 ( 134-130 ka) the Sahara, Nile River desiccated and the Dead Sea watershed were under extreme dry conditions manifested by lake level drop, deposition of salt and enhanced transport of Sahara dusts to the entire studied transect. At the peak of the interglacial MIS 5e ( 130-120 ka), enhanced flooding activity mobilized local fine detritus from the surroundings of the Red Sea and the Dead Sea watershed into the water-bodies. This interval coincided with the Sapropel event S5 in the Mediterranean that responded to enhanced monsoon rains at the heads of the Blue Nile River. At the end of MIS 5e ( 120-116 ka) the effect of the regional floods faded and the Dead Sea and Red Sea areas re-entered sever arid conditions with salt deposition at the Dead Sea. Overall, the desert margins were under turbulent climate regime during the last interglacial period, fluctuating between contraction and expansions manifested with extreme enhanced flooding and extreme arid spells.

Bouguer gravity and crustal structure of the Dead Sea transform fault and adjacent mountain belts in Lebanon

NASA Astrophysics Data System (ADS)

Kamal; Khawlie, Mohamad; Haddad, Fuad; Barazangi, Muawia; Seber, Dogan; Chaimov, Thomas

1993-08-01

The northern extension of the Dead Sea transform fault in southern Lebanon bifurcates into several faults that cross Lebanon from south to north. The main strand, the Yammouneh fault, marks the boundary between the Levantine (eastern Mediterranean) and Arabian plates and separates the western mountain range (Mount Lebanon) from the eastern mountain range (Anti-Lebanon). Bouguer gravity contours in Lebanon approximately follow topographic contours; i.e., positive Bouguer anomalies are associated with the Mount Lebanon and Anti-Lebanon ranges. This suggests that the region is not in simple isostatic compensation. Gravity observations based on 2.5-dimensional modeling and other available geological and geophysical information have produced the following interpretations. (1) The crust of Lebanon thins from ˜35 km beneath the Anti-Lebanon range, near the Syrian border, to ˜27 km beneath the Lebanese coast. No crustal roots exist beneath the Lebanese ranges. (2) The depth to basement is ˜3.5-6 km below sea level under the ranges and is ˜8-10 km beneath the Bekaa depression. (3) The Yammouneh fault bifurcates northward into two branches; one passes beneath the Yammouneh Lake through the eastern part of Mount Lebanon and another bisects the northern part of the Bekaa Valley (i.e., Mid-Bekaa fault). The Lebanese mountain ranges and the Bekaa depression were formed as a result of transtension and later transpression associated with the relative motion of a few crustal blocks in response to the northward movement of the Arabian plate relative to the Levantine plate.

Comprehensive Measurements of Wind Systems at the Dead Sea

NASA Astrophysics Data System (ADS)

Metzger, Jutta; Corsmeier, Ulrich; Kalthoff, Norbert; Wieser, Andreas; Alpert, Pinhas; Lati, Joseph

2016-04-01

The Dead Sea is a unique place on earth. It is located at the lowest point of the Jordan Rift valley and its water level is currently at -429 m above mean sea level (amsl). To the West the Judean Mountains (up to 1000 m amsl) and to the East the Moab mountains (up to 1300 m amsl) confine the north-south oriented valley. The whole region is located in a transition zone of semi-arid to arid climate conditions and together with the steep orography, this forms a quite complex and unique environment. The Virtual Institute DEad SEa Research Venue (DESERVE) is an international project funded by the German Helmholtz Association and was established to study coupled atmospheric, hydrological, and lithospheric processes in the changing environment of the Dead Sea. Previous studies showed that the valley's atmosphere is often governed by periodic wind systems (Bitan, 1974), but most of the studies were limited to ground measurements and could therefore not resolve the three dimensional development and evolution of these wind systems. Performed airborne measurements found three distinct layers above the Dead Sea (Levin, 2005). Two layers are directly affected by the Dead Sea and the third is the commonly observed marine boundary layer over Israel. In the framework of DESERVE a field campaign with the mobile observatory KITcube was conducted to study the three dimensional structure of atmospheric processes at the Dead Sea in 2014. The combination of several in-situ and remote sensing instruments allows temporally and spatially high-resolution measurements in an atmospheric volume of about 10x10x10 km3. With this data set, the development and evolution of typical local wind systems, as well as the impact of regional scale wind conditions on the valley's atmosphere could be analyzed. The frequent development of a nocturnal drainage flow with wind velocities of over 10 m s-1, the typical lake breeze during the day, its onset and vertical extension as well as strong downslope winds in the afternoon, which are often intensified by regional scale wind systems like the Mediterranean Sea Breeze and the coupling of the synoptic flow, will be presented. Bitan, A. (1974). The wind regime in the north-west section of the Dead-Sea. Archiv für Meteorologie, Geophysik und Bioklimatologie, Serie B, 22(4), 313-335. Levin, Z., Gershon, H., & Ganor, E. (2005). Vertical distribution of physical and chemical properties of haze particles in the Dead Sea valley. Atmospheric Environment, 39(27), 4937-4945.

77 FR 14347 - Proposed Information Collection; Comment Request; Reporting of Sea Turtle Incidental Take in...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-09

... interactions with endangered and threatened sea turtles, found both live and dead, in their pound net operations. When a live or dead sea turtle is discovered during a pound net trip, the Virginia pound net...

Water input requirements of the rapidly shrinking Dead Sea

NASA Astrophysics Data System (ADS)

Abu Ghazleh, Shahrazad; Hartmann, Jens; Jansen, Nils; Kempe, Stephan

2009-05-01

The deepest point on Earth, the Dead Sea level, has been dropping alarmingly since 1978 by 0.7 m/a on average due to the accelerating water consumption in the Jordan catchment and stood in 2008 at 420 m below sea level. In this study, a terrain model of the surface area and water volume of the Dead Sea was developed from the Shuttle Radar Topography Mission data using ArcGIS. The model shows that the lake shrinks on average by 4 km2/a in area and by 0.47 km3/a in volume, amounting to a cumulative loss of 14 km3 in the last 30 years. The receding level leaves almost annually erosional terraces, recorded here for the first time by Differential Global Positioning System field surveys. The terrace altitudes were correlated among the different profiles and dated to specific years of the lake level regression, illustrating the tight correlation between the morphology of the terrace sequence and the receding lake level. Our volume-level model described here and previous work on groundwater inflow suggest that the projected Dead Sea-Red Sea channel or the Mediterranean-Dead Sea channel must have a carrying capacity of >0.9 km3/a in order to slowly re-fill the lake to its former level and to create a sustainable system of electricity generation and freshwater production by desalinization. Moreover, such a channel will maintain tourism and potash industry on both sides of the Dead Sea and reduce the natural hazard caused by the recession.

Extreme drying event in the Dead Sea basin during MIS5 from the ICDP Dead Sea Deep Drill Core

NASA Astrophysics Data System (ADS)

Goldstein, S. L.; Stein, M.; Ben-Avraham, Z.; Agnon, A.; Ariztegui, D.; Brauer, A.; Haug, G. H.; Ito, E.; Kitagawa, H.; Torfstein, A.; Yasuda, Y.; The Icdp-Dsddp Scientific Party

2011-12-01

The ICDP funded Dead Sea Deep Drilling Project (DSDDP) recovered the longest and most complete paleo-environmental record in the Middle East, drilling holes of ~450 and ~350 meters in length in deep (~300 m below the lake level) and shallow sites (~3 mbll) respectively. The Dead Sea expands during the glacials and contracts during interglacials, and the sediments comprise a geological archive of the evolving environmental conditions (e.g. rains, floods, dust-storms, droughts). Dead Sea sediments include inorganic aragonite, allowing for dating by U-series (e.g. Haase-Schramm et al. GCA 2004). The deep site cores were opened and described in June 2011. The cores are composed mainly of alternating intervals of marl (aragonite, gypsum and detritus) during glacials, and salts and marls during interglacials. From this stratigraphy we estimate that the deep site core spans ~200 kyr (to the boundary of MIS 6 and 7). A dramatic discovery is a ~40 cm thick interval of partly rounded pebbles at ~235 m below the lake floor. This is the only clean pebbly unit in the entire core. It appears to be a beach layer, near the deepest part of the Dead Sea, lying above ~35 meters of mainly salt. If it is a beach layer, it implies an almost complete dry-down of the paleo-Dead Sea. The pebble layer lies within the last interglacial interval. Our initial attempt to more precisely estimate the age of the possible dry down shows an intriguing correlation between the salt-mud stratigraphy of the Dead Sea core and the oxygen isotope record of Soreq Cave, whereby excursions to light oxygen in the speleothems correspond to periods of salt deposition. Through this comparison, we estimate that the possible dry down occurred during MIS 5e. The occurrence of ~35 meters of mainly salt along with the pebble layer demonstrates a severe dry interval during MIS 5. This observation has implications for the Middle East today, where the Dead Sea level is dropping as all the countries in the area use the runoff. GCM models indicate a more arid future in the region. The core shows that the runoff nearly stopped during a past warm period without human intervention.

Discrimination of Seismic Sources Using Israel Seismic Network.

DTIC Science & Technology

1996-07-01

earthquakes, quarry blasts, underwater explosions and 13 ISN stations in the Dead Sea basin and Negev region 4. Seismogram of event ESI on the Jordanian...1.5 Hz)/A 0 (10 Hz) 51 22. Example of recordings from the Negev quarry blast ES6 53 23. Example of recordings from the Dead Sea earthquake QS3 54 24...Discrimination results for the southern dataset: semblance versus 55 energy ratio IV 25. Velogram analysis, Dead Sea/ Negev region - Discrimination

Near bottom temperature anomalies in the Dead Sea

NASA Astrophysics Data System (ADS)

Ben-Avraham, Zvi; Ballard, Robert D.

1984-12-01

A bottom photographic and temperature study was carried out in the Dead Sea using a miniature version of the unmanned camera system ANGUS (mini-ANGUS). Due to the low transparency of the Dead Sea water, the bottom photographs provide very poor results. Only in a very few locations was the floor visible and in those cases it was found to be a white undulating sedimentary surface. The bottom temperature measurements, which were made continuously along the ship track, indicate the presence of a large zone of temperature anomalies. This zone is located in the deep part of the north basin at a water depth of over 330 m. The anomalies occur above a portion of an east-west fault which cuts through the Dead Sea suggesting the presence of hydrothermal activity.

Energy Balance, Evapo-transpiration and Dew deposition in the Dead Sea Valley

NASA Astrophysics Data System (ADS)

Metzger, Jutta; Corsmeier, Ulrich

2016-04-01

The Dead Sea is a unique place on earth. It is a terminal hypersaline lake, located at the lowest point on earth with a lake level of currently -429 m above mean sea level (amsl). It is located in a transition zone of semiarid to arid climate conditions, which makes it highly sensible to climate change (Alpert1997, Smiatek2011). The Virtual Institute DEad SEa Research Venue (DESERVE) is an international project funded by the German Helmholtz Association and was established to study coupled atmospheric hydrological, and lithospheric processes in the changing environment of the Dead Sea. At the moment the most prominent environmental change is the lake level decline of approximately 1 m / year due to anthropogenic interferences (Gertman, 2002). This leads to noticeable changes in the fractions of the existing terrestrial surfaces - water, bare soil and vegetated areas - in the valley. Thus, the partitioning of the net radiation in the valley changes as well. To thoroughly study the atmospheric and hydrological processes in the Dead Sea valley, which are driven by the energy balance components, sound data of the energy fluxes of the different surfaces are necessary. Before DESERVE no long-term monitoring network simultaneously measuring the energy balance components of the different surfaces in the Dead Sea valley was available. Therefore, three energy balance stations were installed at three characteristic sites at the coast-line, over bare soil, and within vegetation, measuring all energy balance components by using the eddy covariance method. The results show, that the partitioning of the energy into sensible and latent heat flux on a diurnal scale is totally different at the three sites. This results in gradients between the sites, which are e.g. responsible for the typical diurnal wind systems at the Dead Sea. Furthermore, driving forces of evapo-transpiration at the sites were identified and a detailed analysis of the daily evaporation and dew deposition rates for a whole annual cycle will be presented. Alpert, P., Shafir, H., & Issahary, D. (1997). Recent changes in the climate at the Dead Sea-a preliminary study. Climatic Change, 37(3), 513-537. Gertman, I., & Hecht, A. (2002). The Dead Sea hydrography from 1992 to 2000. Journal of marine systems, 35(3), 169-181. Smiatek, G., Kunstmann, H., & Heckl, A. (2011). High-resolution climate change simulations for the Jordan River area. Journal of Geophysical Research: Atmospheres (1984-2012), 116(D16).

Intercomparison of global, ultraviolet B and A radiation measurements in the Dead Sea region (Ein Bokek) and Beer Sheva.

PubMed

Kushelevsky, A P; Kudish, A I

1996-07-01

Thousands of patients suffering from psoriasis have been treated successfully in the Dead Sea area by climatological methods, without medication. This high rate of success, measured in terms of partial to complete plaque clearance and reported to exceed 85% after 3-4 weeks of treatment, has been assumed to be associated with a unique ultraviolet (UV) radiation environment present in the Dead Sea region. In order to broaden our knowledge of the UV radiation environment at the Dead Sea, continuous monitoring of UV (both B and A) and global radiation has recently been initiated at two sites--Ein Bokek (located in the vicinity of the Dead Sea 375 m below mean sea level) and Beer Sheva (315 m above mean sea level)--to facilitate an intercomparison of their respective radiation intensities. The results of the first year of a detailed study of the global, UVB and UVA radiation intensities measured at both sites are summarized and reported in terms of the monthly average daily, average midday (11:00-13:00) and the corresponding maximum values. The radiation data for clear days (based upon the absolute magnitude of the global radiation) were also analyzed to perform an intercomparison between Ein Bokek and Beer Sheva for a winter month and a summer month for which all three types of radiation data were available at both sites.

Salt dissolution and sinkhole formation: Results of laboratory experiments

NASA Astrophysics Data System (ADS)

Oz, Imri; Eyal, Shalev; Yoseph, Yechieli; Ittai, Gavrieli; Elad, Levanon; Haim, Gvirtzman

2016-10-01

The accepted mechanism for the formation of thousands of sinkholes along the coast of the Dead Sea suggests that their primary cause is dissolution of a salt layer by groundwater undersaturated with respect to halite. This is related to the drop in the Dead Sea level, which caused a corresponding drop of the freshwater-saltwater interface, resulting in fresher groundwater replacing the brines that were in contact with the salt layer. In this study we used physical laboratory experiments to examine the validity of this mechanism by reproducing the full dynamic natural process and to examine the impact of different hydrogeological characteristics on this process. The experimental results show surface subsidence and sinkhole formation. The stratigraphic configurations of the aquifer, together with the mechanical properties of the salt layer, determine the dynamic patterns of the sinkhole formation (instantaneous versus gradual formation). Laboratory experiments were also used to study the potential impact of future stratification in the Dead Sea, if and when the "Red Sea-Dead Sea Canal" project is carried out, and the Dead Sea level remains stable. The results show that the dissolution rates are slower by 1 order of magnitude in comparison with a nonstratified saltwater body, and therefore, the processes of salt dissolution and sinkhole formation will be relatively restrained under these conditions.

The 11th Century Collapse of Aqaba on the North Coast of the Gulf of Aqaba, Dead Sea Fault System, Jordan

NASA Astrophysics Data System (ADS)

Niemi, Tina; Allison, Alivia; Rucker, John

2010-05-01

The city of Aqaba is situated at the northern end of the Gulf of Aqaba along the southern part of the Dead Sea Transform Fault. Based both on the historical accounts and archaeological excavations, it is clear that earthquakes have played a significant role in the history of the region. The early Islamic city of Ayla was probably founded around 650 A.D., suffered some damage as a result of the 748 A.D. earthquake, and saw extensive reconstruction around the beginning of the Abbasid period (Whitcomb, 1994). Among other evidence of earthquake destruction at the Islamic city of Ayla is the leaning city Sea wall. Stratified pottery collections from our February 2009 excavation of the buttress of the city wall of Ayla strongly suggest a date for revetment construction in the early 11th Century. Based on the fact that the most recent pottery from sealed loci inside the buttress wall is late Abbasid - Fatimid and the absence of handmade pottery often found in the abandonment phases, the buttress was likely constructed after liquefaction damage from the 1033 earthquake. Damage from distant source earthquakes (748 and 1033) in the ancient city was repaired in antiquity. The destruction and loss of life (accounts claim that all but 12 residents who had been out fishing were killed) caused by the 1068 earthquake may account for the relative ease with which Baldwin I of Jerusalem took over when he arrived with a small retinue in 1116 A.D. Paleoseismic trenches in the modern city of Aqaba indicate that at least two earthquakes have occurred after deposits dated to 1045-1278 A.D. A preliminary analysis of the stratigraphy in new trenches in the Taba sabkha north of Aqaba shows at least three separate faulting events, with the most recent event located at a depth of 70 cm below the ground surface. This finding supports the initial ground penetrating radar survey conducted at the southern end of the Taba sabkha by Abueladas (2005). These data document a long period of quiescence since the last phase of intense earthquake activity along the southern Dead Sea Transform and highlight the elevated potential earthquake hazard in the region.

Dead Sea Scrolls

NASA Technical Reports Server (NTRS)

1994-01-01

A consortium of researchers from Jet Propulsion Laboratory and three other organizations used charged coupled devices (CCDs) and other imaging enhancement technology to decipher previously unreadable portions of the Dead Sea Scrolls. The technique has potentially important implications for archeology.

Crustal stress across the northern Arabian plate and the relationship with the plate boundary forces

NASA Astrophysics Data System (ADS)

Yassminh, Rayan

The region encompassing the collision of northern Arabia with Eurasia is a tectonically heterogeneous region of distributed deformation. The northern Arabia plate is bounded to the west by the subducting Sinai plate and the left-lateral Dead Sea transform. This complexity suggests that there are multiple competing processes that may influence regional tectonics in northern Arabia and adjacent areas. Earthquake mechanisms provide insight into crustal kinematics and stress; however, reliable determination of earthquake source parameters can be challenging in a complex geological region, such as the continental collision zone between the Arabian and Eurasian plates. The goal of this study is to investigate spatial patterns of the crustal stress in the northern Arabian plate and surrounding area. The focal mechanisms used in this study are based on (1) first-motion polarities for earthquakes recorded by Syrian earthquake center during 2000-2011, and (2) regional moment tensors from broadband seismic data, from Turkey and Iraq. First motion focal mechanisms were assigned quality classifications based on the variation of both nodal planes. Regional moment tensor analysis can be significantly influenced by seismic velocity structure; thus, we have divided the study area into regions based on tectonic units. For each region, the velocity model is described using a waveform-modeling technique prior to the regional moment tensor inversion. The resulting focal mechanisms, combined with other previously published focal mechanisms for the study area, provide a basis for stress inversion analysis. The resulting deviatoric stress tensors show the spatial distribution of the maximum horizontal stress varies from NW-SE along the Dead Sea Fault to the N-S toward the east. We interpret this to reflect the eastward change from the transform to collision processes in northern Arabia. Along the Dead Sea Fault, transposition of the sigma-1 and sigma-2 to vertical and horizontal, respectively, may relate to influences from the subducted part of the Sinai plate. This change in regional stress is also consistent with extensional strains observed from GPS velocities.

Crustal structure along the DESERT 2000 Transect inferred from 3-D gravity modelling

NASA Astrophysics Data System (ADS)

El-Kelani, R.; Goetze, H.; Rybakov, M.; Hassouneh, M.; Schmidt, S.

2003-12-01

A three-dimensional interpretation of the newly compiled Bouguer anomaly map is part of the DESERT 2000 Transect. That is multi-disciplinary and multinational project studying for first time the Dead Sea Transform (DST) fault system (DST) from the Mediterranean Sea to Saudi Arabia across the international border in the NW-SE direction. The negative Bouguer anomalies (with magnitude reached "C130 mGal), located into transform valley, are caused by the internal sedimentary basins filled by the light density young sediments (­Y10 km). A high-resolution 3-D model constrained with the seismic results reveals a possible crustal thickness and density distribution beneath the DST valley. The inferred zone of intrusion coincides with the maximum gravity anomaly over the eastern flank of the DST. The intrusion is displaced at different sectors along the NW-SE direction. The zone of the maximum crustal thinning (­30 km) is attained in the western sector at the Mediterranean. The southeastern plateau, on the other hand, shows by far the largest crustal thickness in the region (38-42 km). Linked to the left lateral movement of ~ 105 km at the boundary between the African and Arabian plate, and constrained with the DESERT 2000 seismic data, a small asymmetric topography of the Moho beneath the DST was modelled. The thickness and density of the crust suggest that a continental crust underlies the DST. The deep basins, the relatively large nature of the intrusion and the asymmetric topography of the Moho lead to the conclusion that a small-scale asthenospheric upwelling(?) might be responsible for the thinning of the crust and subsequent rifting of the Dead Sea graben during the left lateral movement.

The Dead Sea

NASA Technical Reports Server (NTRS)

2006-01-01

The Dead Sea is the lowest point on Earth at 418 meters below sea level, and also one of the saltiest bodies of water on Earth with a salinity of about 300 parts-per-thousand (nine times greater than ocean salinity). It is located on the border between Jordan and Israel, and is fed by the Jordan River. The Dead Sea is located in the Dead Sea Rift, formed as a result of the Arabian tectonic plate moving northward away from the African Plate. The mineral content of the Dead Sea is significantly different from that of ocean water, consisting of approximately 53% magnesium chloride, 37% potassium chloride and 8% sodium chloride. In the early part of the 20th century, the Dead Sea began to attract interest from chemists who deduced that the Sea was a natural deposit of potash and bromine. From the Dead Sea brine, Israel and Jordan produce 3.8 million tons potash, 200,000 tons elemental bromine, 45,000 tons caustic soda, 25, 000 tons magnesium metal, and sodium chloride. Both countries use extensive salt evaporation pans that have essentially diked the entire southern end of the Dead Sea.

With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet.

ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products.

The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

Size: 18.5 by 48.1 kilometers (11.5 by 29.8 miles) Location: 31.4 degrees North latitude, 35.4 degrees East longitude Orientation: North at top Image Data: ASTER bands 3, 2, and 1 Original Data Resolution: 15 meters (49.2 feet) Dates Acquired: May 3, 2005

77 FR 41967 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-17

... endangered and threatened sea turtles, found both live and dead, in their pound net operations. When a live or dead sea turtle is discovered during a pound net trip, the Virginia pound net fisherman is...

Should the Dead Sea Be Sustainable?: Investigating Environmental Issues Using a Case Study

ERIC Educational Resources Information Center

Saunders, Cheston Andrew

2016-01-01

Many students leave the environmental science classroom with misconceptions centered on the availability of natural resources such as water. This article presents a case study where students assume the roles of various stakeholders and articulate their position on whether or not to pipe water from the Red Sea to the Dead Sea. Additionally,…

Evolution of genomic diversity and sex at extreme environments: Fungal life under hypersaline Dead Sea stress

PubMed Central

Kis-Papo, Tamar; Kirzhner, Valery; Wasser, Solomon P.; Nevo, Eviatar

2003-01-01

We have found that genomic diversity is generally positively correlated with abiotic and biotic stress levels (1–3). However, beyond a high-threshold level of stress, the diversity declines to a few adapted genotypes. The Dead Sea is the harshest planetary hypersaline environment (340 g·liter–1 total dissolved salts, ≈10 times sea water). Hence, the Dead Sea is an excellent natural laboratory for testing the “rise and fall” pattern of genetic diversity with stress proposed in this article. Here, we examined genomic diversity of the ascomycete fungus Aspergillus versicolor from saline, nonsaline, and hypersaline Dead Sea environments. We screened the coding and noncoding genomes of A. versicolor isolates by using >600 AFLP (amplified fragment length polymorphism) markers (equal to loci). Genomic diversity was positively correlated with stress, culminating in the Dead Sea surface but dropped drastically in 50- to 280-m-deep seawater. The genomic diversity pattern paralleled the pattern of sexual reproduction of fungal species across the same southward gradient of increasing stress in Israel. This parallel may suggest that diversity and sex are intertwined intimately according to the rise and fall pattern and adaptively selected by natural selection in fungal genome evolution. Future large-scale verification in micromycetes will define further the trajectories of diversity and sex in the rise and fall pattern. PMID:14645702

Dead Wolves, Dead Birds, and Dead Trees: Catalysts for Transformative Learning in the Making of Scientist-Environmentalists

ERIC Educational Resources Information Center

Walter, Pierre

2013-01-01

This historical study identifies catalysts for transformative learning in the lives of three scientist-environmentalists important to the 20th-century environmental movement: Aldo Leopold, Rachel Carson, and David Suzuki. Following a brief review of theoretical perspectives on transformative learning, the article argues that transformative…

Occurrence of organohalogens at the Dead Sea Basin

NASA Astrophysics Data System (ADS)

Tubbesing, Christoph; Kotte, Karsten; Keppler, Frank; Krause, Torsten; Bahlmann, Enno; Schöler, Heinfried

2013-04-01

Most arid and semi-arid regions are characterized by evaporites, which are assured sources for volatile organohalogens (VOX) [1]. These compounds play an important role in tropospheric and stratospheric chemistry. The Dead Sea between Israel and Jordan is the world's most famous and biggest all-season water covered salt lake. In both countries chemical plants like the Dead Sea Works and the Arab Potash Company are located at the southern part of the Dead Sea and mine various elements such as bromine and magnesium. Conveying sea water through constructed evaporation pans multifarious salts are enriched and precipitated. In contrast, the Northern basin and main part of the Dead Sea has remained almost untouched by industrial salt production. Its fresh water supply from the Jordan River is constantly decreasing, leading to further increased salinity. During a HALOPROC campaign (Natural Halogenation Processes in the Environment) we collected various samples including air, soils, sediments, halophytic plants, ground- and seawater from the Northern and Southern basin of the Israeli side of the Dead Sea. These samples were investigated for the occurrence of halocarbons using different analytical techniques. Most samples were analyzed for volatile organohalogens such as haloalkanes using gas chromatography- mass spectrometry (GC-MS). Interestingly, there is a strong enrichment of trihalomethanes (THM), especially all chlorinated and brominated ones and also the iodinated compound dichloroiodomethane were found in the Southern basin. In addition, volatile organic carbons (VOC) such as ethene and some other alkenes were analyzed by a gas chromatography-flame ionisation detector (GC-FID) to obtain further information about potential precursors of halogenated compounds. Halophytic plants were investigated for their potential to release chloromethane and bromomethane but also for their stable carbon and hydrogen isotope composition. For this purpose, a plant chamber was constructed to encase branches of halophytic plants to estimate their organohalogen emissions using adsorbent tubes or vacuum cans, respectively. Our results show that several halocarbons are ubiquitous at the Dead Sea basin and their formation depends on environmental factors such as salinity and vegetation. [1] Kotte et al., 2012, Biogeosciences, 9, 1225-1235

Lithology of the long sediment record recovered by the ICDP Dead Sea Deep Drilling Project (DSDDP)

NASA Astrophysics Data System (ADS)

Neugebauer, Ina; Brauer, Achim; Schwab, Markus J.; Waldmann, Nicolas D.; Enzel, Yehouda; Kitagawa, Hiroyuki; Torfstein, Adi; Frank, Ute; Dulski, Peter; Agnon, Amotz; Ariztegui, Daniel; Ben-Avraham, Zvi; Goldstein, Steven L.; Stein, Mordechai

2014-10-01

The sedimentary sections that were deposited from the Holocene Dead Sea and its Pleistocene precursors are excellent archives of the climatic, environmental and seismic history of the Levant region. Yet, most of the previous work has been carried out on sequences of lacustrine sediments exposed at the margins of the present-day Dead Sea, which were deposited only when the lake surface level rose above these terraces (e.g. during the Last Glacial period) and typically are discontinuous due to major lake level variations in the past. Continuous sedimentation can only be expected in the deepest part of the basin and, therefore, a deep drilling has been accomplished in the northern basin of the Dead Sea during winter of 2010-2011 within the Dead Sea Deep Drilling Project (DSDDP) in the framework of the ICDP program. Approximately 720 m of sediment cores have been retrieved from two deep and several short boreholes. The longest profile (5017-1), revealed at a water depth of ˜300 m, reaches 455 m below the lake floor (blf, i.e. to ˜1175 m below global mean sea level) and comprises approximately the last 220-240 ka. The record covers the upper part of the Amora (penultimate glacial), the Last Interglacial Samra, the Last Glacial Lisan and the Holocene Ze'elim Formations and, therewith, two entire glacial-interglacial cycles. Thereby, for the first time, consecutive sediments deposited during the MIS 6/5, 5/4 and 2/1 transitions were recovered from the Dead Sea basin, which are not represented in sediments outcropping on the present-day lake shores. In this paper, we present essential lithological data including continuous magnetic susceptibility and geochemical scanning data and the basic stratigraphy including first chronological data of the long profile (5017-1) from the deep basin. The results presented here (a) focus on the correlation of the deep basin deposits with main on-shore stratigraphic units, thus providing a unique comprehensive stratigraphic framework for regional paleoenvironmental reconstruction, and (b) highlight the outstanding potential of the Dead Sea deep sedimentary archive to record hydrological changes during interglacial, glacial and transitional intervals.

Vertical Mixing in the Dead Sea

NASA Astrophysics Data System (ADS)

Gertman, Isaac; Ozer, Tal; Katsenelson, Boris; Lensky, Nadav

2015-04-01

For hundreds of years, the Dead Sea was characterized by a stable haline stratification, supported by runoff. The penetration of the winter convection was limited to an upper mixed layer (UML) of about 30-50 m. Below the UML, a stable halocline prevented the mixing. As a result of the runoff reduction, the UML salinity increased and the gravitational stability diminished. During the winter of 1978-1979, the sea water overturned, ending the long-term stable hydrological regime. Since 1979, the haline stratification structure reoccurred twice after extremely rainy winters, in 1980-82 and 1992-1995. In other years, the sea was entirely mixed by winter thermal convection ( which occurs from November to March ) and had a seasonal pycnocline beneath the UML during summer. Profiles of temperature and quasi-salinity (density anomaly from 1000 kg/m3 for the chosen reference temperature of 32° C) during the last 19 years, show the formation of summer ``overturning halocline'' beneath the UML, and the thermocline that supports the stable stratification. Another warm and saline layer is formed also during the summer period near the bottom. This layer spreads from the southern part of the sea, where end-brine is discharged to the sea from the Israeli and Jordanian salt plants' evaporation ponds. The end-brine has extremely high salinity (˜ 350 g/kg) and, in spite of the high temperatures ( ˜ 45° C), high density (1350 kg/m^3), it therefore spreads as a gravitational current in the Dead Sea deep basin. Estimation of the density ratio (Rρ) for the Dead Sea water (where measurements of water salinity is quite difficult) was done using quasi-salinity (σ32) and potential temperature (θ): Rρ= [α(partialθ/partial z)]/[β(partial σ32/partial z)], where α and β are temperature expansion and quasi-salinity contraction coefficients respectively. The values of α and β for the Dead Sea water were defined from water samples collected during 2008. The Rρ values confirm that the summer Dead Sea thermohaline structure is appropriate for double diffusion mixing. A salt fingers regime beneath the UML (1.3< Rρ

Three-dimensional modeling of pull-apart basins: implications for the tectonics of the Dead Sea Basin

USGS Publications Warehouse

Katzman, Rafael; ten Brink, Uri S.; Lin, Jian

1995-01-01

We model the three-dimensional (3-D) crustal deformation in a deep pull-apart basin as a result of relative plate motion along a transform system and compare the results to the tectonics of the Dead Sea Basin. The brittle upper crust is modeled by a boundary element technique as an elastic block, broken by two en echelon semi-infinite vertical faults. The deformation is caused by a horizontal displacement that is imposed everywhere at the bottom of the block except in a stress-free “shear zone” in the vicinity of the fault zone. The bottom displacement represents the regional relative plate motion. Results show that the basin deformation depends critically on the width of the shear zone and on the amount of overlap between basin-bounding faults. As the width of the shear zone increases, the depth of the basin decreases, the rotation around a vertical axis near the fault tips decreases, and the basin shape (the distribution of subsidence normalized by the maximum subsidence) becomes broader. In contrast, two-dimensional plane stress modeling predicts a basin shape that is independent of the width of the shear zone. Our models also predict full-graben profiles within the overlapped region between bounding faults and half-graben shapes elsewhere. Increasing overlap also decreases uplift near the fault tips and rotation of blocks within the basin. We suggest that the observed structure of the Dead Sea Basin can be described by a 3-D model having a large overlap (more than 30 km) that probably increased as the basin evolved as a result of a stable shear motion that was distributed laterally over 20 to 40 km.

The taxonomic status of "Halobacterium marismortui" from the Dead Sea: a comparison with Halobacterium vallismortis

NASA Technical Reports Server (NTRS)

Oren, A.; Lau, P. P.; Fox, G. E.

1988-01-01

A Halobacterium strain, isolated by Ginzburg et al. from the Dead Sea in the late 1960's, often referred to as "Halobacterium marismortui" or "Halobacterium of the Dead Sea" (deposited in the American Type Culture Collection as ATCC 43049) was compared with Halobacterium (Haloarcula) vallismortis ATCC 29715. The strains appeared to be very closely related, as shown by the near identity of their 5S and 16S ribosomal RNA's, and a large number of other common properties. Distinct differences exist, however, in cell morphology, and in their potency to utilize different sugars and other compounds.

Taxonomic analysis of extremely halophilic archaea isolated from 56-years-old dead sea brine samples.

PubMed

Arahal, D R; Gutiérrez, M C; Volcani, B E; Ventosa, A

2000-10-01

A taxonomic study comprising both phenotypic and genotypic characterization, has been carried out on a total of 158 extremely halophilic aerobic archaeal strains. These strains were isolated from enrichments prepared from Dead Sea water samples dating from 1936 that were collected by B. E. Volcani for the demonstration of microbial life in the Dead Sea. The isolates were examined for 126 morphological, physiological, biochemical and nutritional tests. Numerical analysis of the data, by using the S(J) coefficient and UPGMA clustering method, showed that the isolates clustered into six phenons. Twenty-two out of the 158 strains used in this study were characterized previously (ARAHAL et al., 1996) and were placed into five phenotypic groups. The genotypic study included both the determination of the guanineplus-cytosine content of the DNA and DNA-DNA hybridization studies. For this purpose, representative strains from the six phenons were chosen. These groups were found to represent some members of three different genera - Haloarcula (phenons A, B, and C), Haloferax (phenons D and E) and Halobacterium (phenon F) - of the family Halobacteriaceae, some of them never reported to occur in the Dead Sea, such as Haloarcula hispanica, while Haloferax volcanii (phenons D and E) was described in the Dead Sea by studies carried out several decades later than Volcani's work.

Improved marine reservoir age estimation and palaeoclimate synchronisation of the early Holocene Levantine/NW-Arabian region based on identification of the S1 tephra in Dead Sea and Tayma palaeolake sediments

NASA Astrophysics Data System (ADS)

Neugebauer, Ina; Wulf, Sabine; Schwab, Markus J.; Serb, Johanna; Plessen, Birgit; Appelt, Oona; Brauer, Achim

2017-04-01

Due to a lack of tephras identified in marine and terrestrial palaeoclimate records from the Levantine-Arabian area, this region is still not sufficiently connected to the eastern Mediterranean tephrostratigraphical lattice. Here we report on the first finding of cryptotephra in the Holocene lacustrine sediment records of the Dead Sea and the Tayma palaeolake (NW Arabian Peninsula). The major elemental chemistry of the rhyolitic glass shards proves this tephra identical to the distal 'S1 tephra' identified in the Yammoûneh palaeolake, Lebanon (Develle et al, 2009), in a marine sediment record from the SE Levantine basin (Hamann et al., 2010) and in the Sodmein Cave archaeological site in Egypt (Barton et al., 2015). The 'S1 tephra', most likely corresponding to the early Holocene 'Dikkartın' dome eruption of the Erciyes Daǧ volcano in central Anatolia, Turkey, has been dated in the marine record at 8830 ± 140 cal yr BP. We present new age estimates of the 'S1 tephra' based on radiocarbon dating of terrestrial plant remains (Migowski et al., 2004) and pollen concentrates (Dinies et al., 2015), which reveal modelled ages of 8939 ± 83 cal yr BP in the Dead Sea sediments and 9041 ± 254 cal yr BP in Tayma. This allows the estimation of an early Holocene marine reservoir age of ca. 320 years in the SE Levantine Sea. The timing of the volcanic eruption during the early Holocene humid period, which led to the formation of sapropel S1 in the Mediterranean Sea, and the identification of the 'S1 tephra' more than 1200 km to the south are crucial for the synchronisation of marine and terrestrial palaeoclimate records in the eastern Mediterranean region. References: Barton et al., 2015. The role of cryptotephra in refining the chronology of Late Pleistocene human evolution and cultural change in North Africa. Quaternary Sci. Rev. 118, 151-169. Develle et al., 2009. Early Holocene volcanic ash fallout in the Yammoûneh lacustrine basin (Lebanon): Tephrochronological implications for the Near East. Journal of Volcanology and Geothermal Research 186, 416-425. Dinies et al., 2015. When the desert was green: Grassland expansion during the early Holocene in northwestern Arabia. Quatern. Int. 382, 293-302. Hamann et al., 2010. First evidence of a distal early Holocene ash layer in Eastern Mediterranean deep-sea sediments derived from the Anatolian volcanic province. Quaternary Res. 73, 497-506. Migowski et al., 2004. Recurrence pattern of Holocene earthquakes along the Dead Sea transform revealed by varve-counting and radiocarbon dating of lacustrine sediments. Earth Planet. Sc. Lett. 222, 301-314.

Earth observation image of the Dead Sea taken during STS-100

NASA Image and Video Library

2001-04-26

S100-E-5366 (26 April 2001) --- The southern part of the Dead Sea and parts of Israel and Jordan were photographed with a digital still camera by the crew members aboard the Space Shuttle Endeavour on April 26, 2001.

Space Radar Image of Jerusalem and the Dead Sea

NASA Image and Video Library

1999-04-15

This space radar image shows the area surrounding the Dead Sea along the West Bank between Israel and Jordan. This region is of major cultural and historical importance to millions of Muslims, Jews and Christians who consider it the Holy Land.

Ultraviolet radiation properties as applied to photoclimatherapy at the Dead Sea.

PubMed

Kudish, A I; Abels, D; Harari, M

2003-05-01

The Dead Sea basin, the lowest terrestrial point on earth, is recognized as a natural treatment center for patients with various cutaneous and rheumatic diseases. Psoriasis is the major skin disease treated at the Dead Sea with excellent improvement to complete clearance exceeding 85% after 4 weeks of treatment. These results were postulated to be associated with a unique spectrum of ultraviolet radiation present in the Dead Sea area. The UVB and UVA radiation at two sites is measured continuously by identical sets of broad-band Solar Light Co. Inc. meters (Philadelphia, PA). The spectral selectivity within the UVB and UVA spectrum was determined using a narrow-band spectroradiometer, UV-Optronics 742 (Orlando, FL). The optimum exposure time intervals for photoclimatherapy, defined as the minimum ratio of erythema to therapeutic radiation intensities, were also determined using a Solar Light Co. Inc. Microtops II, Ozone Monitor-Sunphotometer. The ultraviolet radiation at the Dead Sea is attenuated relative to Beer Sheva as a result of the increased optical path length and consequent enhanced scattering. The UVB radiation is attenuated to a greater extent than UVA and the shorter erythema UVB spectral range decreased significantly compared with the longer therapeutic UVB wavelengths. It was demonstrated that the relative attenuation within the UVB spectral range is greatest for the shorter erythema rays and less for the longer therapeutic UVB wavelengths, thus producing a greater proportion of the longer therapeutic UVB wavelengths in the ultraviolet spectrum. These measurements can be utilized to minimize the exposure to solar radiation by correlating the cumulative UVB radiation dose to treatment efficacy and by formulating a patient sun exposure treatment protocol for Dead Sea photoclimatherapy.

Stress tensor and focal mechanisms in the Dead Sea basin

NASA Astrophysics Data System (ADS)

Hofstetter, A.; Dorbath, C.; Dorbath, L.; Braeuer, B.; Weber, M. H.

2015-12-01

We use the recorded seismicity, confined to the Dead Sea basin and its boundaries, by the Dead Sea Integrated Research (DESIRE) portable seismic network and the Israel and Jordan permanent seismic networks for studying the mechanisms of earthquakes that occurred in the Dead Sea basin. The observed seismicity in the Dead Sea basin was divided into 9 regions according to the spatial distribution of the earthquakes and the known tectonic features. The large number of recording stations and the good station distribution allowed the reliable determinations of 494 earthquake focal mechanisms. For each region, based on the inversion of the observed polarities of the earthquakes, we determine the focal mechanisms and the associated stress tensor. For 159 earthquakes out of the 494 mechanisms we could determine compatible fault planes. On the eastern side, the focal mechanisms are mainly strike-slip mechanism with nodal planes in the N-S and E-W directions. The azimuths of the stress axes are well constrained presenting minimal variability in the inversion of the data, which is in good agreement with the Arava fault on the eastern side of the Dead Sea basin and what we had expected from the regional geodynamics. However, larger variabilities of the azimuthal and dip angles are observed on the western side of the basin. Due to the wider range of azimuths of the fault planes, we observe the switching of sigma1 and sigma2 or the switching of sigma2 and sigma3as major horizontal stress directions. This observed switching of stress axes allows having dip-slip and normal mechanisms in a region that is dominated by strike-slip motion.

EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES

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

Brigmon, R; Penny Morris, P; Garriet Smith, G

2008-01-28

Evaporitic environments are found in a variety of depositional environments as early as the Archean. The depositional settings, microbial community and mineralogical composition vary significantly as no two settings are identical. The common thread linking all of the settings is that evaporation exceeds precipitation resulting in elevated concentrations of cations and anions that are higher than in oceanic systems. The Dead Sea and Storrs Lake are examples of two diverse modern evaporitic settings as the former is below sea level and the latter is a coastal lake on an island in the Caribbean. Each system varies in water chemistry asmore » the Dead Sea dissolved ions originate from surface weathered materials, springs, and aquifers while Storrs Lake dissolved ion concentration is primarily derived from sea water. Consequently some of the ions, i.e., Sr, Ba are found at significantly lower concentrations in Storrs Lake than in the Dead Sea. The origin of the dissolved ions are ultimately responsible for the pH of each system, alkaline versus mildly acidic. Each system exhibits unique biogeochemical properties as the extreme environments select certain microorganisms. Storrs Lake possesses significant biofilms and stromatolitic deposits and the alkalinity varies depending on rainfall and storm activity. The microbial community Storrs Lake is much more diverse and active than those observed in the Dead Sea. The Dead Sea waters are mildly acidic, lack stromatolites, and possess a lower density of microbial populations. The general absence of microbial and biofilm fossilization is due to the depletion of HCO{sub 3} and slightly acidic pH.« less

New perspectives on interdisciplinary earth science at the Dead Sea: The DESERVE project.

PubMed

Kottmeier, Christoph; Agnon, Amotz; Al-Halbouni, Djamil; Alpert, Pinhas; Corsmeier, Ulrich; Dahm, Torsten; Eshel, Adam; Geyer, Stefan; Haas, Michael; Holohan, Eoghan; Kalthoff, Norbert; Kishcha, Pavel; Krawczyk, Charlotte; Lati, Joseph; Laronne, Jonathan B; Lott, Friederike; Mallast, Ulf; Merz, Ralf; Metzger, Jutta; Mohsen, Ayman; Morin, Efrat; Nied, Manuela; Rödiger, Tino; Salameh, Elias; Sawarieh, Ali; Shannak, Benbella; Siebert, Christian; Weber, Michael

2016-02-15

The Dead Sea region has faced substantial environmental challenges in recent decades, including water resource scarcity, ~1m annual decreases in the water level, sinkhole development, ascending-brine freshwater pollution, and seismic disturbance risks. Natural processes are significantly affected by human interference as well as by climate change and tectonic developments over the long term. To get a deep understanding of processes and their interactions, innovative scientific approaches that integrate disciplinary research and education are required. The research project DESERVE (Helmholtz Virtual Institute Dead Sea Research Venue) addresses these challenges in an interdisciplinary approach that includes geophysics, hydrology, and meteorology. The project is implemented by a consortium of scientific institutions in neighboring countries of the Dead Sea (Israel, Jordan, Palestine Territories) and participating German Helmholtz Centres (KIT, GFZ, UFZ). A new monitoring network of meteorological, hydrological, and seismic/geodynamic stations has been established, and extensive field research and numerical simulations have been undertaken. For the first time, innovative measurement and modeling techniques have been applied to the extreme conditions of the Dead Sea and its surroundings. The preliminary results show the potential of these methods. First time ever performed eddy covariance measurements give insight into the governing factors of Dead Sea evaporation. High-resolution bathymetric investigations reveal a strong correlation between submarine springs and neo-tectonic patterns. Based on detailed studies of stratigraphy and borehole information, the extension of the subsurface drainage basin of the Dead Sea is now reliably estimated. Originality has been achieved in monitoring flash floods in an arid basin at its outlet and simultaneously in tributaries, supplemented by spatio-temporal rainfall data. Low-altitude, high resolution photogrammetry, allied to satellite image analysis and to geophysical surveys (e.g. shear-wave reflections) has enabled a more detailed characterization of sinkhole morphology and temporal development and the possible subsurface controls thereon. All the above listed efforts and scientific results take place with the interdisciplinary education of young scientists. They are invited to attend joint thematic workshops and winter schools as well as to participate in field experiments. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Constraints on evaporation and dilution of terminal, hypersaline lakes under negative water balance: The Dead Sea, Israel

NASA Astrophysics Data System (ADS)

Zilberman, Tami; Gavrieli, Ittai; Yechieli, Yoseph; Gertman, Isaac; Katz, Amitai

2017-11-01

The response of hypersaline terminal lakes to negative water balance was investigated by studying brines evaporating to extreme salinities in sinkholes along the western coast of the Dead Sea and during on-site evaporation experiments of the Dead Sea brine. Density and temperature were determined in the field and all samples were analyzed for their major and a few minor solutes. The activity of H2O (aH2O) in the brines was calculated, and the degree of evaporation (DE) was established using Sr2+as a conservative solute. The relations between density and water activity were obtained by polynomial regression, and the relation between the lake's volume and level was established using Hall's (1996) hypsographic model for the Dead Sea basin. Relating the results to the modern, long-term relative humidity (RH) over the basin shows that (a) The lowermost attainable level of a terminal lake undergoing evaporation with no inflow is dictated by the median RH; this level represents equilibrium between the brine's aH2O and RH; (b) Small, saline water bodies with high surface to volume ratios (A/V), such as the hypersaline brines in the sinkholes, are very sensitive to short term changes in RH; in these, the brines' aH2O closely follows the seasonal changes; (c) the level decline of the Dead Sea due to evaporation under present climatic conditions and assuming no inflow to the lake may continue down to 516-537 m below mean sea level (bmsl), corresponding to a water activity range of 0.46-0.39 in its brine, in equilibrium with the overlying relative air humidity; this suggests that the lake level cannot drop more than ∼100 m from its present level; and (d) The maximum RH values that existed over the precursor lake of the Dead Sea (Lake Lisan) during geologically reconstructed minima levels can be similarly calculated.

Groundwater-saline lakes interaction - The contribution of saline groundwater circulation to solute budget of saline lakes: a lesson from the Dead Sea

NASA Astrophysics Data System (ADS)

Kiro, Yael; Weinstein, Yishai; Starinsky, Abraham; Yechieli, Yoseph

2013-04-01

Saline lakes act as base level for both surface water and groundwater. Thus, a change in lake levels is expected to result in changes in the hydrogeological system in its vicinity, exhibited in groundwater levels, location of the fresh-saline water interface, sub-lacustrine groundwater discharge (SGD) and saline water circulation. All these processes were observed in the declining Dead Sea system, whose water level dropped by ~35 meters in the last 50 years. This work focuses mainly on the effect of circulation of Dead Sea water in the aquifer, which continues even in this very rapid base level drop. In general, seawater circulation in coastal aquifers is now recognized as a major process affecting trace element mass balances in coastal areas. Estimates of submarine groundwater discharge (SGD) vary over several orders of magnitude (1-1000000 m3/yr per meter shoreline). These estimates are sensitive to fresh-saline SGD ratios and to the temporal and spatial scales of the circulation. The Dead Sea system is an excellent natural field lab for studying seawater-groundwater interaction and large-scale circulation due to the absence of tides and to the minor role played by waves. During Dead Sea water circulation in the aquifer several geochemical reactions occur, ranging from short-term adsorption-desorption reactions and up to long-term precipitation and dissolution reactions. These processes affect the trace element distribution in the saline groundwater. Barite and celestine, which are supersaturated in the lake water, precipitate during circulation in the aquifer, reducing barium (from 5 to 1.5 mg/L), strontium (from 350 to 300 mg/L) and the long-lived 226Ra (from 145 to 60 dpm/L) in the saline groundwater. Redox-controlled reactions cause a decrease in uranium from 2.4 to 0.1 μg/L, and an increase in iron from 1 to 13 mg/L. 228Ra (t1/2=5.75 yr) activity in the Dead Sea is ~1 dpm/L and increase gradually as the saline water flows further inland until reaching steady-state activities (~27 dpm/L) with the aquifer sediments. The decrease in 226Ra and increase in 228Ra in the circulation process provide a robust method for calculating the amount of Dead Sea water circulating in the aquifer. This process can affect trace element concentrations in the Dead Sea and emphasize the potential of long-term seawater circulation in mass balances of saline water bodies.

Stratigraphy, climate and downhole logging data - an example from the ICDP Dead Sea deep drilling project

NASA Astrophysics Data System (ADS)

Coianiz, Lisa; Ben-Avraham, Zvi; Lazar, Michael

2017-04-01

During the late Quaternary a series of lakes occupied the Dead Sea tectonic basin. The sediments that accumulated within these lakes preserved the environmental history (tectonic and climatic) of the basin and its vicinity. Most of the information on these lakes was deduced from exposures along the marginal terraces of the modern Dead Sea, e.g. the exposures of the last glacial Lake Lisan and Holocene Dead Sea. The International Continental Drilling Program (ICDP) project conducted in the Dead Sea during 2010-2011 recovered several cores that were drilled in the deep depocenter of the lake (water depth of 300 m) and at the margin (depth of 3 m offshore Ein Gedi spa). New high resolution logging data combined with a detailed lithological description and published age models for the deep 5017-1-A borehole were used to establish a sequence stratigraphic framework for the Lakes Amora, Samra, Lisan and Zeelim strata. This study presents a stratigraphic timescale for reconstructing the last ca 225 ka. It provides a context within which the timing of key sequence surfaces identified in the distal part of the basin can be mapped on a regional and stratigraphic time frame. In addition, it permitted the examination of depositional system tracts and related driving mechanisms controlling their formation. The sequence stratigraphic model developed for the Northern Dead Sea Basin is based on the identification of sequence bounding surfaces including: sequence boundary (SB), transgressive surface (TS) and maximum flooding surface (MFS). They enabled the division of depositional sequences into a Lowstand systems tracts (LST), Transgressive systems tracts (TST) and Highstand systems tracts (HST), which can be interpreted in terms of relative lake level changes. The analysis presented here show that system tract stacking patterns defined for the distal 5017-1-A borehole can be correlated to the proximal part of the basin, and widely support the claim that changes in relative lake levels were synchronous across the northern Dead Sea, although differences do exist. These discrepancies can possibly be explained in part by the tectonic nature of the basin. Within the 5017-1-A section, the interpreted changes in depositional environments derived primarily from the gamma ray log patterns show a good correlation in time with sequence-chronostratigraphic framework, extracted lake level curves and paleohydrological records of other areas worldwide. Sequence stratigraphic analysis presented here allows for a detailed, high resolution examination of the sedimentary sequences in the Northern Dead Sea Basin together with an independent proxy that is an indirect indicator of changes in relative lake level.

Antimicrobial Activity of Bacillus Persicus 24-DSM Isolated from Dead Sea Mud.

PubMed

Al-Karablieh, Nehaya

2017-01-01

Dead Sea is a hypersaline lake with 34% salinity, gains its name due to the absence of any living macroscopic creatures. Despite the extreme hypersaline environment, it is a unique ecosystem for various halophilic microorganisms adapted to this environment. Halophilic microorganisms are known for various potential biotechnological applications, the purpose of the current research is isolation and screening of halophilic bacteria from Dead Sea mud for potential antimicrobial applications. Screening for antagonistic bacteria was conducted by bacterial isolation from Dead Sea mud samples and agar plate antagonistic assay. The potential antagonistic isolates were subjected to biochemical characterization and identification by 16S-rRNA sequencing. Among the collected isolates, four isolates showed potential antagonistic activity against Bacillus subtilis 6633 and Escherichia coli 8739. The most active isolate (24-DSM) was subjected for antagonistic activity and minimal inhibitory concentration against different gram positive and negative bacterial strains after cultivation in different salt concentration media. Results: The results of 16S-rRNA analysis revealed that 24-DSM is very closely related to Bacillus persicus strain B48, which was isolated from hypersaline lake in Iran. Therefore, the isolate 24-DSM is assigned as a new strain of B. persicusi isolated from the Dead Sea mud. B. persicusi 24-DSM showed higher antimicrobial activity, when it was cultivated with saline medium, against all tested bacterial strains, where the most sensitive bacterial strain was Corynebacterium diphtheria 51696.

First results from a temporary seismological network in the Southern Dead Sea area

NASA Astrophysics Data System (ADS)

Braeuer, B.; Asch, G.; Hofstetter, A.; Haberland, C.; Darwish, J.; El-Kelani, R.; Weber, M.

2008-12-01

Within the framework of the international project DESIRE (Dead Sea Integrated Research Project) a local seismological network was operated in the Southern Dead Sea area as a co-operation between the GFZ Germany, GII Israel, NRA Jordan and An-Najah National Univer-sity Palestine. From October 2006 to March 2008 about 65 short period (38) and broadband (27) instruments recorded continuously the seismicity of the Dead Sea basin. This investiga-tion aims in studying the deeper structure of the Dead Sea area based on the distribution of the local seismicity. About 500 local events have been recorded and more than 300 have been processed up to now. A dominant feature in this first part of the dataset we found a cluster of 78 earthquakes, occurring in February 2007, including multiplets. We determined a 1D-reference model of P- and S-velocities using Velest (Kissling et al., 1994). The model shows a high velocity increase between 6 and 10 km depth. This could be related to a prominent reflector found in the results of the wide angle reflection experiment in the area in 2006 (Mechie et al., 2008). The station corrections suggest a 2D structure with the basin in the middle and the shoulders on the east and west. Additionally the results are compared with receiver function and magnetotelluric studies, part of the DESIRE project.

Continuous CO2 escape from the hypersaline Dead Sea caused by aragonite precipitation

NASA Astrophysics Data System (ADS)

Golan, Rotem; Lazar, Boaz; Wurgaft, Eyal; Lensky, Nadav; Ganor, Jiwchar; Gavrieli, Ittai

2017-06-01

Chemical precipitation of CaCO3 occurs in diverse marine and lacustrine environments. In the hypersaline Ca-chloride lakes that have been occupying the Dead Sea basin since the late Pleistocene, CaCO3 precipitated, mostly as aragonite. The aragonite sediments precipitated mainly during periods of high lake level stands as a result of mixing of bicarbonate-rich freshwater runoff with Dead Sea brine, that is Ca-rich and have high Mg/Ca ratio. During periods of arid conditions with limited freshwater inflow, water level declined, salinity increased and gypsum and halite became the dominant evaporitic minerals to precipitate. The present study investigates the carbon cycle of the Dead Sea under the current limited water and bicarbonate supply to the brine, representing periods of extremely arid conditions. The decrease of inflows to the Dead Sea in recent years stems mainly from diversion of freshwater from the drainage basin and results in dramatic water level decline and massive halite precipitation. During 2013-2014, bi-monthly depth profiles of total alkalinity, dissolved inorganic carbon (DIC) and its isotopic composition (δ13C) were conducted in the Dead Sea, from surface down to the bottom of the lake (290 m). Mass balance calculations conducted for the period 1993-2013 show that while inventories of conservative ions such as Mg2+ remained constant, the net DIC inventory of the lake decreased by ∼10%. DIC supply to the lake during this period, however, amounted to ∼10% of lake's inventory indicating that during 20 years, the lake lost ∼20% of its 1993s inventory. Compilation of historical data with our data shows that during the past two decades the lake's low DIC (∼1 mmol kg-1) and very high PCO2 (1800 ppm V) remained relatively constant, suggesting that a quasi-steady-state situation prevails. In spite of the surprisingly stable DIC and CO2 concentrations, during this 20 year period δ13CDIC increased significantly, from 1.4‰ to 2.7‰. An isotopic mass balance calculation together with the high PCO2 of the brine show that during that period the lake lost about 3.7 · 1010 moles of DIC, of which ∼60% by CO2 degassing and ∼40% by aragonite precipitation. The deviation from the common 1:1 CO2:CaCO3 ratio in most aqueous systems is facilitated by the dominance of the borate alkalinity of the Dead Sea. Nucleation and crystal growth experiments suggest that throughout this time the Dead Sea remained supersaturated with respect to aragonite, a situation facilitated by combination of slow nucleation rates and absence of growth surfaces. The very high PCO2 of the Dead Sea is maintained by the low CO2 piston velocity of the brine, calculated to be only ∼4.5 m yr-1, more than an order of magnitude slower than seawater value.

Dead Sea drawdown and monsoonal impacts in the Levant during the last interglacial

NASA Astrophysics Data System (ADS)

Torfstein, Adi; Goldstein, Steven L.; Kushnir, Yochanan; Enzel, Yehouda; Haug, Gerald; Stein, Mordechai

2015-02-01

Sediment cores recovered by the Dead Sea Deep Drilling Project (DSDDP) from the deepest basin of the hypersaline, terminal Dead Sea (lake floor at ∼725 m below mean sea level) reveal the detailed climate history of the lake's watershed during the last interglacial period (Marine Isotope Stage 5; MIS5). The results document both a more intense aridity during MIS5 than during the Holocene, and the moderating impacts derived from the intense MIS5e African Monsoon. Early MIS5e (∼133-128 ka) was dominated by hyperarid conditions in the Eastern Mediterranean-Levant, indicated by thick halite deposition triggered by a lake-level drop. Halite deposition was interrupted however, during the MIS5e peak (∼128-122 ka) by sequences of flood deposits, which are coeval with the timing of the intense precession-forced African monsoon that generated Mediterranean sapropel S5. A subsequent weakening of this humidity source triggered extreme aridity in the Dead Sea watershed and resulting in the biggest known lake level drawdown in its history, reflected by the deposition of thick salt layers, and a capping pebble layer corresponding to a hiatus at ∼116-110 ka. The DSDDP core provides the first evidence for a direct association of the African monsoon with mid subtropical latitude climate systems effecting the Dead Sea watershed. Combined with coeval deposition of Arabia and southern Negev speleothems, Arava travertines, and calcification of Red Sea corals, the evidence points to a climatically wet corridor that could have facilitated homo sapiens migration "out of Africa" during the MIS5e peak. The hyperaridity documented during MIS5e may provide an important analogue for future warming of arid regions of the Eastern Mediterranean-Levant.

Geophysical analysis of the recent sinkhole trend at Ghor-Haditha (Dead Sea, Jordan)

NASA Astrophysics Data System (ADS)

Camerlynck, Christian; Bodet, Ludovic; Galibert, Pierre-Yves; Boucher, Marie; Al-Zoubi, Abdallah

2013-04-01

For essentially the last 30 year the water level of the Dead Sea has highly dropped. One of the major associated facts is sinkhole occurrences along the shoreline both in Jordan and Israel. As the principal invoked mechanism, many studies have concluded that sinkhole formation results from the dissolution of a previously immersed salt layer, progressively in contact with fresh to brackish water. In Jordan, the triggering of this phenomenon could also be the result of particular tectonic settings, associated with the Jordan-Dead Sea transform fault system. At Ghor Haditha (south-est Jordan), the consequences have been dramatic for farmers with the shrinking of temporary available lands and industry with the closing of at least one factory. The shallow material in this area is heterogeneous and composed of intercalated sand and clay layers of alluvial-colluvial origin, over a salty substratum, whose precise depth and thickness are yet partially hypothesized. Between 2005 and 2008, a multi-method high-resolution geophysical survey was performed, approximately over a 1 km2 area at Ghor Haditha, associating mainly electromagnetic soundings, magnetic resonance soundings (MRS), and seismic profiling, ground-penetrating radar and electrical resistivity tomography. At the same time, this specific area was the location of a dramatic evolution of sinkhole occurences, regularly followed by geodetic measurements. Over the 3 years period, about 120 TEM (Transient ElectroMagnetic) soundings allow to map precisely the depth of the conductive layers below the resistive overburden. Two conductive layer are then revealed, the latter showing the lowest resistivity below 1 Ohm.m corresponding to the saline substratum. Several MRS (3 in 2005, repeated in 2007 and 12 additional soundings) show an east-west hydraulic gradient towards the Dead. However, the main sinkhole trend coincides with both: - a clear low transmissivity axis determined from MRS measurements; - the western side of a depression into the top of the most conductive layer. This shows so clearly a correlation between the recent sinkhole phenomenon and the current water circulations, but paleo-topography below the Pleistocene deposits mays equally be a clue in the sinkhole hazard.

Anatomy of the dead sea transform from lithospheric to microscopic scale

USGS Publications Warehouse

Weber, M.; Abu-Ayyash, K.; Abueladas, A.; Agnon, A.; Alasonati-Tasarova, Z.; Al-Zubi, H.; Babeyko, A.; Bartov, Y.; Bauer, K.; Becken, M.; Bedrosian, P.A.; Ben-Avraham, Z.; Bock, G.; Bohnhoff, M.; Bribach, J.; Dulski, P.; Ebbing, J.; El-Kelani, R.; Forster, A.; Forster, H.-J.; Frieslander, U.; Garfunkel, Z.; Goetze, H.J.; Haak, V.; Haberland, C.; Hassouneh, M.; Helwig, S.; Hofstetter, A.; Hoffmann-Rotrie, A.; Jackel, K.H.; Janssen, C.; Jaser, D.; Kesten, D.; Khatib, M.; Kind, R.; Koch, O.; Koulakov, I.; Laske, Gabi; Maercklin, N.; Masarweh, R.; Masri, A.; Matar, A.; Mechie, J.; Meqbel, N.; Plessen, B.; Moller, P.; Mohsen, A.; Oberhansli, R.; Oreshin, S.; Petrunin, A.; Qabbani, I.; Rabba, I.; Ritter, O.; Romer, R.L.; Rumpker, G.; Rybakov, M.; Ryberg, T.; Saul, J.; Scherbaum, F.; Schmidt, S.; Schulze, A.; Sobolev, S.V.; Stiller, M.; Stromeyer, D.; Tarawneh, K.; Trela, C.; Weckmann, U.; Wetzel, U.; Wylegalla, K.

2009-01-01

Fault zones are the locations where motion of tectonic plates, often associated with earthquakes, is accommodated. Despite a rapid increase in the understanding of faults in the last decades, our knowledge of their geometry, petrophysical properties, and controlling processes remains incomplete. The central questions addressed here in our study of the Dead Sea Transform (DST) in the Middle East are as follows: (1) What are the structure and kinematics of a large fault zone? (2) What controls its structure and kinematics? (3) How does the DST compare to other plate boundary fault zones? The DST has accommodated a total of 105 km of leftlateral transform motion between the African and Arabian plates since early Miocene (???20 Ma). The DST segment between the Dead Sea and the Red Sea, called the Arava/ Araba Fault (AF), is studied here using a multidisciplinary and multiscale approach from the ??m to the plate tectonic scale. We observe that under the DST a narrow, subvertical zone cuts through crust and lithosphere. First, from west to east the crustal thickness increases smoothly from 26 to 39 km, and a subhorizontal lower crustal reflector is detected east of the AF. Second, several faults exist in the upper crust in a 40 km wide zone centered on the AF, but none have kilometer-size zones of decreased seismic velocities or zones of high electrical conductivities in the upper crust expected for large damage zones. Third, the AF is the main branch of the DST system, even though it has accommodated only a part (up to 60 km) of the overall 105 km of sinistral plate motion. Fourth, the AF acts as a barrier to fluids to a depth of 4 km, and the lithology changes abruptly across it. Fifth, in the top few hundred meters of the AF a locally transpressional regime is observed in a 100-300 m wide zone of deformed and displaced material, bordered by subparallel faults forming a positive flower structure. Other segments of the AF have a transtensional character with small pull-aparts along them. The damage zones of the individual faults are only 5-20 m wide at this depth range. Sixth, two areas on the AF show mesoscale to microscale faulting and veining in limestone sequences with faulting depths between 2 and 5 km. Seventh, fluids in the AF are carried downward into the fault zone. Only a minor fraction of fluids is derived from ascending hydrothermal fluids. However, we found that on the kilometer scale the AF does not act as an important fluid conduit. Most of these findings are corroborated using thermomechanical modeling where shear deformation in the upper crust is localized in one or two major faults; at larger depth, shear deformation occurs in a 20-40 km wide zone with a mechanically weak decoupling zone extending subvertically through the entire lithosphere. Copyright 2009 by the American Geophysical Union.

Clustering and interpretation of local earthquake tomography models in the southern Dead Sea basin

NASA Astrophysics Data System (ADS)

Bauer, Klaus; Braeuer, Benjamin

2016-04-01

The Dead Sea transform (DST) marks the boundary between the Arabian and the African plates. Ongoing left-lateral relative plate motion and strike-slip deformation started in the Early Miocene (20 MA) and produced a total shift of 107 km until presence. The Dead Sea basin (DSB) located in the central part of the DST is one of the largest pull-apart basins in the world. It was formed from step-over of different fault strands at a major segment boundary of the transform fault system. The basin development was accompanied by deposition of clastics and evaporites and subsequent salt diapirism. Ongoing deformation within the basin and activity of the boundary faults are indicated by increased seismicity. The internal architecture of the DSB and the crustal structure around the DST were subject of several large scientific projects carried out since 2000. Here we report on a local earthquake tomography study from the southern DSB. In 2006-2008, a dense seismic network consisting of 65 stations was operated for 18 months in the southern part of the DSB and surrounding regions. Altogether 530 well-constrained seismic events with 13,970 P- and 12,760 S-wave arrival times were used for a travel time inversion for Vp, Vp/Vs velocity structure and seismicity distribution. The work flow included 1D inversion, 2.5D and 3D tomography, and resolution analysis. We demonstrate a possible strategy how several tomographic models such as Vp, Vs and Vp/Vs can be integrated for a combined lithological interpretation. We analyzed the tomographic models derived by 2.5D inversion using neural network clustering techniques. The method allows us to identify major lithologies by their petrophysical signatures. Remapping the clusters into the subsurface reveals the distribution of basin sediments, prebasin sedimentary rocks, and crystalline basement. The DSB shows an asymmetric structure with thickness variation from 5 km in the west to 13 km in the east. Most importantly, a well-defined body under the eastern part of the basin down to 18 km depth was identified by the algorithm. Considering its geometry and petrophysical signature, this unit is interpreted as prebasin sediments and not as crystalline basement. The seismicity distribution supports our results, where events are concentrated along boundaries of the basin and the deep prebasin sedimentary body.

[Book Review] The Dead Sea, the lake and its setting, edited by T. Niemi, Z. Ben-Avraham, J. Gat

USGS Publications Warehouse

ten Brink, Uri S.

1998-01-01

Review of The Dead Sea, the Lake and its Setting. Tina M. Niemi, Zvi Ben-Avraham, and Joel R. Gat (Editors). Oxford Monographs on Geology and Geophysics No. 36. Oxford University Press, N.Y. 286 pp. ISBN 0-19-508703-8, 1997. $75.

Literary Genres in Poetic Texts from the Dead Sea Scrolls

ERIC Educational Resources Information Center

Pickut, William Douglas

2017-01-01

Among the texts of the Dead Sea Scrolls, there are four literary compositions that bear the superscriptional designations shir and mizmor. These designations correspond directly to superscriptional designations provided many times in both the now-canonical Psalter and the various witnesses to those texts unearthed at Qumran. On its face, this fact…

A new interpretation of seismic tomography in the southern Dead Sea basin using neural network clustering techniques

NASA Astrophysics Data System (ADS)

Braeuer, Benjamin; Bauer, Klaus

2015-11-01

The Dead Sea is a prime location to study the structure and development of pull-apart basins. We analyzed tomographic models of Vp, Vs, and Vp/Vs using self-organizing map clustering techniques. The method allows us to identify major lithologies by their petrophysical signatures. Remapping the clusters into the subsurface reveals the distribution of basin sediments, prebasin sedimentary rocks, and crystalline basement. The Dead Sea basin shows an asymmetric structure with thickness variation from 5 km in the west to 13 km in the east. Most importantly, we identified a distinct, well-defined body under the eastern part of the basin down to 18 km depth. Considering its geometry and petrophysical signature, this unit is interpreted as a buried counterpart of the shallow prebasin sediments encountered outside of the basin and not as crystalline basement. The seismicity distribution supports our results, where events are concentrated along boundaries of the basin and the deep prebasin sedimentary body. Our results suggest that the Dead Sea basin is about 4 km deeper than assumed from previous studies.

Dead Sea deep cores: A window into past climate and seismicity

NASA Astrophysics Data System (ADS)

Stein, Mordechai; Ben-Avraham, Zvi; Goldstein, Steven L.

2011-12-01

The area surrounding the Dead Sea was the locus of humankind's migration out of Africa and thus has been the home of peoples since the Stone Age. For this reason, understanding the climate and tectonic history of the region provides valuable insight into archaeology and studies of human history and helps to gain a better picture of future climate and tectonic scenarios. The deposits at the bottom of the Dead Sea are a geological archive of the environmental conditions (e.g., rains, floods, dust storms, droughts) during ice ages and warm ages, as well as of seismic activity in this key region. An International Continental Scientific Drilling Program (ICDP) deep drilling project was performed in the Dead Sea between November 2010 and March 2011. The project was funded by the ICDP and agencies in Israel, Germany, Japan, Norway, Switzerland, and the United States. Drilling was conducted using the new Large Lake Drilling Facility (Figure 1), a barge with a drilling rig run by DOSECC, Inc. (Drilling, Observation and Sampling of the Earth's Continental Crust), a nonprofit corporation dedicated to advancing scientific drilling worldwide. The main purpose of the project was to recover a long, continuous core to provide a high resolution record of the paleoclimate, paleoenvironment, paleoseismicity, and paleomagnetism of the Dead Sea Basin. With this, scientists are beginning to piece together a record of the climate and seismic history of the Middle East during the past several hundred thousand years in millennial to decadal to annual time resolution.

[THE EFFECT OF 5 DAYS IMMERSION IN DEAD SEA WATER ON BLOOD GLUCOSE LEVELS IN TYPE 2 DIABETES MELLITUS PATIENTS].

PubMed

Brzezinski Sinai, Isaac; Lior, Yotam; Brzezinski Sinai, Noa; Harari, Marco; Liberty, Idit F

2016-02-01

Body immersion in plain water or mineral water induces significant and unique physiological changes in most body systems. In a previous pilot study, a significant reduction in blood glucose levels among diabetes mellitus (DM) patients was found following a single immersion in Dead Sea water but not after immersion in plain water. To study the immediate and long term effects of immersion in mineral water for five consecutive days on blood glucose in patients with type 2 DM. A total of 34 patients with type 2 DM were divided into 2 groups: The first immersed in a plain water pool and the second immersed in a Dead Sea water pool; both pools were warmed to a temperature of 35°C. Immersions for 20 minutes occurred twice daily: two hours after breakfast and before dinner. Seven samples of capillary blood glucose levels were taken: fasting, before and after every immersion, prior to lunch and before bedtime. Hemoglobin A1C (HbA1c) was taken prior to the study and a re-check was conducted during the 12 weeks following the study. Blood glucose levels significantly decreased immediately after immersion both in Dead Sea water and plain water compared to their values prior to immersion (p<0.001). No significant difference was noted between both types of water. A decrease in fasting glucose levels was observed only in the group immersed in Dead Sea water when compared to plain water (6.83±5.68 mg/dl versus 4.37±1.79 respectively and the difference was close to statistical significance (p=0.071. There were no changes in HbA1c levels. Immersion for 20 minutes in water (Dead Sea or plain water) at a temperature of 35°C induced an immediate reduction in glucose levels in patients with type 2 DM.

Using palynology to re-assess the Dead Sea laminated sediments - Indeed varves?

NASA Astrophysics Data System (ADS)

Bookman, Revital; Lopez-Merino, Lourdes; Belmaker, Reuven; Eshel, Amram; Epshtein Epshtein, Valentina; Leroy, Suzanne

2017-04-01

Lacustrine laminated sediments are often varves representing annual rhythmic deposition. The Dead Sea high-stand laminated sections consist of mm-scale alternating detrital and authigenic aragonite laminae. Previous studies assumed these laminae were varves; detritus deposition during the winter and aragonite in the summer. These sequences were used for varve counting and chronology, however this assumption has never been robustly validated. Here, we report an examination of the seasonal deposition of detrital and aragonite couplets from two well-known Late Holocene laminated sections at the Ze'elim fan-delta using palynology and grain-size distribution analyses. These analyses are complemented by the study of contemporary flash-flood samples and multivariate statistical analysis. Because transport affects the pollen preservation state, well-preserved (mostly) air-borne transported pollen was analysed separately from badly-preserved pollen and fungal spores, which are more indicative of water transport and reworking from soils. Our results indicate that (i) both detrital and aragonite laminae were deposited during the rainy season; (ii) aragonite laminae have significantly lower reworked pollen and fungal spore concentrations than detrital and flash-flood samples; and (iii) detrital laminae are composed of recycling of local and distal sources, with coarser particles that were initially deposited in the Dead Sea watershed and later transported via run-off to the lake. The conclusions suggest that detrital and aragonite couplets in the Dead Sea laminated sediments are most likely not varves and that the laminae deposition is related to the occurrence of flash-flood events. Consequently, at least for the Holocene sequences, laminated sediments cannot be considered as varves and Quaternary laminated sequences should be re-evaluated. The Dead Sea Basin laminated sequences (as the ICDP Dead Sea Deep Drilling Project record) should be used for the reconstruction of palaeo-flash flood records that will have a significant impact on understanding the palaeo-hydrology of the DSB and its implication to high-resolution climatic interpretation.

Responses to the 2800 years BP climatic oscillation in shallow- and deep-basin sediments from the Dead Sea

NASA Astrophysics Data System (ADS)

Neugebauer, Ina; Brauer, Achim; Schwab, Markus; Dulski, Peter; Frank, Ute; Hadzhiivanova, Elitsa; Kitagawa, Hiroyuki; Litt, Thomas; Schiebel, Vera; Taha, Nimer; Waldmann, Nicolas

2015-04-01

Laminated lake sediments from the Dead Sea basin provide high-resolution records of climatic variability in the eastern Mediterranean region, which is considered being especially sensitive to changing climatic conditions. In the study presented here, we aim to reconstruct palaeoclimatic changes and their relation to the frequency of flood/erosion and dust deposition events as archived in the Dead Sea basin for the time interval from ca 3700 to 1700 years BP. A ca 4 m thick, mostly annually laminated (varved) sediment section from the western margin of the Dead Sea (shallow-water DSEn - Ein Gedi profile) was analysed and correlated to the new ICDP Dead Sea Deep Drilling Project core 5017-1 from the deep basin. To detect even single event layers, we applied a multi-proxy approach of high-resolution microscopic thin section analyses, µXRF element scanning and magnetic susceptibility measurements, supported by grain size and palynological analyses. Based on radiocarbon and varve dating two pronounced dry periods were detected at ~3500-3300 yrs BP and ~2900-2400 yrs BP that are characterized by a sand deposit during the older dry period and enhanced frequency of coarse detrital layers during the younger dry period in the shallow-water DSEn core, both interpreted as increased erosion processes. In the 5017-1 deep-basin core these dry periods are depicted by halite deposits. The timing of the younger dry period broadly coincides with the Homeric Minimum of solar activity at ca 2800 yrs BP. Our results suggest that during this period the Dead Sea region experienced a change in synoptic weather patterns leading to an increased occurrence of flash-flood events, overprinting the overall dry climatic conditions. Following this dry spell, a 250-yrs period of increased dust deposition is observed, coinciding with more regular aragonite precipitation during less arid climatic conditions.

Modeling radium distribution in coastal aquifers during sea level changes: The Dead Sea case

USGS Publications Warehouse

Kiro, Yael; Yechieli, Yoseph; Voss, Clifford I.; Starinsky, Abraham; Weinstein, Yishai

2012-01-01

We present a new approach to studying the behavior of radium isotopes in a coastal aquifer. In order to simulate radium isotope distributions in the dynamic flow field of the Dead Sea aquifer, a multi-species density dependent flow model (SUTRA-MS) was used. Field data show that the activity of 226Ra decreases from 140 to 60 dpm/L upon entering the aquifer from the Dead Sea, and then further decreases linearly due to mixing with Ra-poor fresh water. On the other hand, an increase is observed in the activity of the shorter-lived isotopes (up to 52 dpm/L 224Ra and 31 dpm/L 223Ra), which are relatively low in Dead Sea water (up to 2.5 dpm/L 224Ra and 0.5 dpm/L 223Ra). The activities of the short lived radium isotopes also decrease with decreasing salinity, which is due to the effect of salinity on the adsorption of radium. The relationship between 224Ra and salinity suggests that the adsorption partition coefficient (K) is linearly related to salinity. Simulations of the steady-state conditions, show that the distance where equilibrium activity is attained for each radium isotope is affected by the isotope half-life, K and the groundwater velocity, resulting in a longer distance for the long-lived radium isotopes. K affects the radium distribution in transient conditions, especially that of the long-lived radium isotopes. The transient conditions in the Dead Sea system, with a 1 m/yr lake level drop, together with the radium field data, constrains K to be relatively low (226Ra cannot be explained by adsorption, and it is better explained by removal via coprecipitation, probably with barite or celestine.

Implications of S1 tephra findings in Dead Sea and Tayma palaeolake sediments for marine reservoir age estimation and palaeoclimate synchronisation

NASA Astrophysics Data System (ADS)

Neugebauer, Ina; Wulf, Sabine; Schwab, Markus J.; Serb, Johanna; Plessen, Birgit; Appelt, Oona; Brauer, Achim

2017-08-01

Here we report on the first findings of a cryptotephra in the Holocene lacustrine sediment records of the Dead Sea and Tayma palaeolake (NW Arabian Peninsula). The major element glass composition of this rhyolitic tephra is identical to the distal 'S1' tephra layer identified in the Yammoûneh palaeolake (Lebanon), in a marine sediment record from the SE Levantine basin and in the Sodmein Cave archaeological site in Egypt. The S1 tephra corresponds to the early Holocene 'Dikkartın' dome eruption of the Erciyes Dağ volcano in central Anatolia (Turkey) and has been dated in the marine record at 8830 ± 140 cal yr BP. We present new age estimates of the S1 tephra based on radiocarbon dating of terrestrial plant remains and pollen concentrates revealing ages of 8939 ± 83 cal yr BP in the Dead Sea sediments and 9041 ± 254 cal yr BP in Tayma. The precise date from the Dead Sea allows refining the early Holocene marine reservoir age in the SE Levantine Sea to ca. 320 ± 50 years. Synchronisation of marine and terrestrial palaeoclimate records in the eastern Mediterranean region using the S1 tephra further suggests a time-transgressive expansion of the early Holocene humid period.

The Fall of an Academic Cyberbully

ERIC Educational Resources Information Center

Kolowich, Steve

2009-01-01

Few academic debates are as contentious as those surrounding the Dead Sea Scrolls. These fragments of some 800 ancient documents include portions of all but one book of the Hebrew Bible. The first ones were discovered in 1947 by shepherds in caves on the northwestern shore of the Dead Sea, and are believed to be the oldest surviving Judaic…

View of the ODS in the Atlantis payload bay prior to docking

NASA Image and Video Library

1996-09-17

STS079-824-081 (16-26 Sept. 1996) --- In this 70mm frame from the space shuttle Atlantis, the Jordan River Valley can be traced as it separates Lebanon, Palestine and Israel on the west, from Syria and Jordan on the east. The river flows along the Dead Sea rift; the east side of the fault zone (Syria, Jordan, Saudi Arabia) has moved north about 100 kilometers relative to the west side (Lebanon, Israel, Egypt) during the past 24 million years. The Dead Sea and Sea of Galilee are in depressions formed where faults of the zone diverge or step over. The Dead Sea once covered the area of salt evaporation pans (the bright blue water). The lagoon, barrier islands and evaporite deposits (bright white) along the Mediterranean coast of the Sinai Peninsula (lower left of frame) are just east of Port Said.

The 1170 and 1202 CE Dead Sea Rift earthquakes and long-term magnitude distribution of the Dead Sea Fault zone

USGS Publications Warehouse

Hough, S.E.; Avni, R.

2009-01-01

In combination with the historical record, paleoseismic investigations have provided a record of large earthquakes in the Dead Sea Rift that extends back over 1500 years. Analysis of macroseismic effects can help refine magnitude estimates for large historical events. In this study we consider the detailed intensity distributions for two large events, in 1170 CE and 1202 CE, as determined from careful reinterpretation of available historical accounts, using the 1927 Jericho earthquake as a guide in their interpretation. In the absence of an intensity attenuation relationship for the Dead Sea region, we use the 1927 Jericho earthquake to develop a preliminary relationship based on a modification of the relationships developed in other regions. Using this relation, we estimate M7.6 for the 1202 earthquake and M6.6 for the 1170 earthquake. The uncertainties for both estimates are large and difficult to quantify with precision. The large uncertainties illustrate the critical need to develop a regional intensity attenuation relation. We further consider the distribution of magnitudes in the historic record and show that it is consistent with a b-value distribution with a b-value of 1. Considering the entire Dead Sea Rift zone, we show that the seismic moment release rate over the past 1500 years is sufficient, within the uncertainties of the data, to account for the plate tectonic strain rate along the plate boundary. The results reveal that an earthquake of M7.8 is expected within the zone on average every 1000 years. ?? 2011 Science From Israel/LPPLtd.

The Last Interglacial in the Levant: Perspective from the ICDP Dead Sea Deep Drill Core

NASA Astrophysics Data System (ADS)

Goldstein, S. L.; Torfstein, A.; Stein, M.; Kushnir, Y.; Enzel, Y.; Haug, G. H.

2014-12-01

Sediments recovered by the ICDP Dead Sea Deep Drilling Project provide a new perspective on the climate history of the Levant during the last interglacial period MIS5. They record the extreme impacts of an intense interglacial characterized by stronger insolation, warmer mean global temperatures, and higher sea-levels than the Holocene. Results show both extreme hyper-aridity during MIS5e, including an unprecedented drawdown of Dead Sea water levels, and the impacts of a strong precession-driven African monsoon responsible for a major sapropel event (S5) in the eastern Mediterranean. Hyper-arid conditions at the beginning of MIS5e prior to S5 (~132-128 ka) are evidenced by halite deposition, indicating declining Dead Sea lake levels. Surprisingly, the hyper-arid phase is interrupted during the MIS5e peak (~128-120 ka), coinciding with the S5 sapropel, which is characterized by a thick (23 m) section of silty detritus (without any halite) whose provenance indicates southern-sourced wetness in the watershed. Upon weakening of the S5 monsoon (~120-115 ka), the return of extreme aridity resulted in an unprecedented lake level drawdown, reflected by massive salt deposition, and followed by a sediment hiatus (~115-100 ka) indicating prolonged low lake level. The resumption of section follows classic Levant patterns with more wetness during cooler MIS5b and hyper-aridity during warmer MIS5a. The ICDP core provides the first evidence for a direct linkage between an intense precession-driven African monsoon and wetness at the high subtropical latitude (~30N) of the Dead Sea watershed. Combined with coeval deposition of Negev speleothems and travertines, and calcitification of Red Sea corals, the evidence indicates a wet climatic corridor that could facilitate homo sapiens migration out of Africa during the MIS5e peak. In addition, the MIS 5e hyper-arid intervals may provide an important cautionary analogue for the impact of future warming on regional water resources.

Earth observations taken during STS-77 mission

NASA Image and Video Library

1996-05-28

STS077-732-093 (19-29 May 1996) --- This high oblique perspective from the Space Shuttle Endeavour shows the Dead Sea Rift Valley and the surrounding deserts. North is to the right side of the frame. The vegetation line on the coast between Egypt and Israel is clearly visible. Crete is visible in the Mediterranean Sea. The Dead Sea was formed approximately 3 million years ago. A passage opened up to the sea and the water poured in. It is about 1,300 feet below sea level. It is fed by the Jordan River and numerous mineral springs from the surrounding hills. It is estimated to contain 43 million metric tons of salt. The salinity is 32 percent.

Lethality of sea lamprey attacks on lake trout in relation to location on the body surface

USGS Publications Warehouse

Bergstedt, Roger A.; Schneider, Clifford P.; O'Gorman, Robert

2001-01-01

We compared the locations of healed attack marks of the sea lamprey Petromyzon marinus on live lake trout Salvelinus namaycush with those of unhealed attack marks on dead lake trout to determine if the lethality of a sea lamprey attack was related to attack location. Lake trout were collected from Lake Ontario, live fish with gill nets in September 1985 and dead fish with trawls in October 1983−1986. Attack location was characterized by the percent distances from snout to tail and from the ventral to the dorsal midline. Kolmogorov−Smirnov two-sample tests did not detect significant differences in the distribution of attack location along either the anteroposterior axis or the dorsoventral axis. When attack locations were grouped into six anatomical regions historically used to record sea lamprey attacks, dead fish did not exhibit a significantly higher proportion of attacks in the more anterior regions. Even if the differences in attack location on live and dead fish were significant, they were too small to imply substantial spatial differences in attack lethality that should be accounted for when modeling the effects of sea lampreys feeding on lake trout. We suggest that the tendency for sea lamprey attacks to occur on the anterior half of the fish is related to the lower amplitude of lateral body movement there during swimming and thus the lower likelihood of being dislodged.

77 FR 38774 - Marine Mammals; File No. 16193

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-29

... whole blood taken from dead or captive individuals to study reproductive physiology, including endocrinology, gamete biology, and cryophysiology. Specimens from dead animals, located solely within the... harvesting; killed incidentally to fishing or other operations; found dead at sea or beached; or that died of...

Passive recording of an active transform, an example from the Levant continental margin and the Dead Sea Fault

NASA Astrophysics Data System (ADS)

Lang, Guy; Lazar, Michael; Schattner, Uri

2017-04-01

Transform faults accommodate lateral motion between two adjacent plates. Records of plate motion and consequent boundary development on land is, at times, scarce and limited to structures along the fault axis. Investigation of a passive continental margin adjacent to the plate boundary might broaden the scope and provide estimates for its structural development. To examine this hypothesis, we analyzed depth and time migrated 3D seismic data together with four boreholes located along the southern Levant continental margin, ca. 100 Km from the continental Dead Sea fault (DSF). The analysis focus on the Plio-Pleistocene sequence, a key period in the development of the DSF. It includes formation of structural maps, stacking pattern investigation and calculation of sedimentation rates based on decompacted 3D depth data. These, in turn, enabled the reconstruction of margin development. This includes Messinian-earliest Zanclean NNE-SSW sinistral strike-slip faulting followed by Zanclean-Late Gelasian syn-depositional folding striking in the same direction. Abrupt change is marked by the Top Gelasian surface that shows indications of regional mass slumping. Successive Mid-Late Pleistocene progradation marks a basinward shift of the depocenter. Progradation controls margin sedimentation rates during the mid-late Pleistocene. These were found to increase throughout the whole Plio-Pleistocene, in contrast to reported sediment discharge from the Nile, which was shown to decrease after the Gelasian. Correlations to onshore findings, suggest that the continental margin records strain localization on the DSF during the Pliocene-Gelasian. This trend peaked at 1.8 Ma when short wavelength strain ceased along the margin, and differential subsidence commenced basinwards. This is attributed to consequent deepening of the DSF plate boundary.

Sinai peninsula taken by the STS-109 crew

NASA Image and Video Library

2002-03-02

STS109-708-024 (1-12 March 2002) --- The astronauts on board the Space Shuttle Columbia took this 70mm picture featuring the Sinai Peninsula and the Dead Sea Rift. The left side of the view is dominated by the great triangle of the Sinai peninsula, which is partly obscured by an unusual cloud mass on this day. The famous Monastery of St. Catherine lies in the very remote, rugged mountains in the southern third of the peninsula (foreground). The Gulf of Aqaba is a finger of the Red Sea bottom center, pointing north to the Dead Sea, the small body of water near the center of the view. According to NASA scientists studying the STS-109 photo collection, the gulf and the Dead Sea are northerly extensions of the same geological rift that resulted in the opening of the Red Sea . The Gulf of Suez appears in the lower left corner. Northwest Saudi Arabia occupies the lower right side of the view, Jordan and Syria the right and top right, and the Eastern Mediterranean Sea the top left. Thin white lines of cloud have formed along the coastal mountains of southern Turkey and stretch across the top of the view near the Earth's limb.

The circulation of the Dead Sea brine in the regional aquifer

NASA Astrophysics Data System (ADS)

Weber, Nurit; Yechieli, Yoseph; Stein, Mordechai; Yokochi, Reika; Gavrieli, Ittai; Zappala, Jake; Mueller, Peter; Lazar, Boaz

2018-07-01

Ca-chloride brines have circulated between the lakes and the adjacent aquifers throughout the history of the Dead Sea lacustrine-hydrology system. The Ein-Qedem (EQ) hydrothermal saline springs system discharging at the western shores of the modern Dead Sea is the modern manifestation of this essential and continuous process. The EQ springs comprise the most significant source of Ca-chloride brine that currently discharges into the lake. The chemical composition of EQ brine has remained virtually uniform during the past ca. 40 yr, indicating that the brine represents a large groundwater reservoir. The EQ brine evolved from ancient Ca-chloride brine that occupied the tectonic depression of the Dead Sea Basin during the Quaternary. During this period, the composition of lake's brine was affected by mixing with freshwater and formation of primary minerals. Based on chronological and geochemical data, we argue that the EQ brine comprises the epilimnetic solution of last glacial Lake Lisan that penetrated and circulated through the adjacent Judea Group aquifer. 14C and 81Kr dating indicates recharge ages spanning the time interval of ∼40-20 ka, coinciding with the period when the lake reached its highest stand (of ∼ 200 ± 30 m below msl, at ∼31-17.4 ka) and maintained a stable layered (stratified) configuration for a period of several ten thousand years. The presented evidence suggests that the circulation of the Ca-chloride brine involves penetration into the aquifer during high stands (EQ brine recharge) and its discharge back into the lake during the modern low stands (∼400 to 430 m below msl). Accordingly, the mechanism of brine circulation between the lake and the marginal aquifers is related to the long-term hydro-climate history of the Dead Sea basin and its vicinity.

Anthropogenic-enhanced erosion following the Neolithic Revolution in the Southern Levant: Records from the Dead Sea deep drilling core

NASA Astrophysics Data System (ADS)

Lu, Yin; Waldmann, Nicolas; Nadel, Dani; Marco, Shmuel

2017-04-01

In addition to tectonics and climatic changes, humans have exerted a significant impact on surface erosion over timescales ranging from years to centuries. However, such kind of impact over millennial timescales remains unsubstantiated. The Dead Sea drainage basin offers a rare combination of well-documented substantial climate change, intense tectonics and abundant archaeological evidence for past human activity in the Southern Levant. It serves as a natural laboratory for understanding how sedimentation rates in a deep basin are related to climate change, tectonics, and anthropogenic impacts on the landscape. Here we show how basin-wide erosion rates are recorded by thicknesses of rhythmic detritus laminae and clastic sediment accumulation rates in a long core retrieved by the Dead Sea Deep Drilling Project in the Dead Sea depocenter. During the last 11.5 kyr the average detrital accumulation rate is 3-4 times that during the last two glacial cycles (MIS 7c-2), and the average thickness of detritus laminae in the last 11.6 kyr is 4.5 times that between 21.7 and 11.6 ka, implying an increased erosion rate on the surrounding slopes during the Holocene. We estimate that this intensified erosion is incompatible with tectonic and climatic regimes during the corresponding time interval and further propose a close association with the Neolithic Revolution in the Levant (beginning at 11.5 ka). We thus suggest that human impact on the landscape was the primary driver causing the intensified erosion and that the Dead Sea sedimentary record serves as a reliable recorder of this impact since the Neolithic Revolution.

A 300m-width sinkhole threatens the stability of the embankment of a saltpan in Jordan, Dead Sea Region

NASA Astrophysics Data System (ADS)

Closson, Damien; Abou Karaki, Najib; Pasquali, Paolo; Riccardi, Paolo

2013-04-01

Since the 1980s, the Dead Sea coastal zone is affected by sinkholes. The dynamic of the salt karst system is attested by a drastic increase of collapse events. The energy available for sub-surface erosion (or cavities genesis) is related to the head difference between the water table and the lake level which drop down at an accelerating rate of more than 1 m/yr. In the region of Ghor Al Haditha, Jordan, the size of the craters increased significantly during the last decade. Up to now, the greatest compound structure observed (association of metric subsidence, decametric sinkholes, and landslides) was about 150-200 m in diameter. End of December 2012, a single circular structure having 250-300 m in diameter was identified within a 10 km x 1.5 km saltpan of the Arab Potash Company. This finding raises questions regarding the origin of the underlying cavity and the capability of prediction of all models developed up to now in Israel and Jordan regarding the Dead Sea sinkholes. The analysis of satellite images of the past shows that the appearance of this unique depression is very recent (probably less than 5 years). Cosmo-SkyMed radar images have been processed to map the associated deformation field. Ground motions attest that the overall diameter could be around 600 m. Currently, this sinkhole is threatening the stability of more than one kilometer of a 12 km long dike holding 90 million m3 of Dead Sea brine. This case study underlines the great fragility of the Dead Sea salt karst and demonstrates the need for the setting up of an early warning system.

Optically stimulated luminescence of natural NaCl mineral from Dead Sea exposed to gamma radiation.

PubMed

Roman-Lopez, J; Piña López, Y I; Cruz-Zaragoza, E; Marcazzó, J

2018-08-01

In this work, the continuous wave - optically stimulated luminescence (CW-OSL) emissions of natural salt minerals, collected from Dead Sea in summer of 2015, were studied. The CW-OSL dose response of natural salt showed a linear range between 0.5Gy and 10Gy of gamma radiation of 60 Co. Samples exposed at 3Gy exhibited good repeatability with a variation coefficient of 4.6%. The CW-OSL response as function of the preheating temperature (50-250°C) was analyzed. An increase of 15% of the CW-OSL response was observed in NaCl samples during storage period of 336h. The results showed that the natural Dead Sea salt minerals could be applied as natural dosimeter of gamma radiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Consequences of the anthropogenic alterations along the Jordanian Dead Sea coast

NASA Astrophysics Data System (ADS)

Closson, Damien; Abou Karaki, Najib

2014-05-01

The Dead Sea is a terminal lake located over the Jordan - Dead Sea transform fault. At around 428 m bsl, it is the lowest emerged place on Earth. Since the 1960s, the over-exploitation of the water resources in the catchment area has lead to lower the level at an increasing pace. In 2014, it is upper than 1m/year. In the last 50 years, a 50 by 15 km slice of brine, around 33 m thick, has disappeared. With a salinity ten times greater than the average ocean water, the lake and its underground lateral extensions act as a high density layer over which the fresh groundwater is in hydrostatic equilibrium. The slope of the interface between saline and fresh waters is ten times shallower than normally expected near the ocean. According to a number of wells, in some places, the water table does not drop at the same speed than the Dead Sea. There, the head difference is constantly increasing. The fresh groundwater moves rapidly towards the lake to compensate for the imbalance. The most conspicuous consequence is the proliferation of thousands of sinkholes and wide shallow subsidence. In parallel, in the last two decades, industrial and touristic developments have taken place along the coast. Hence, such a dynamic environment provides a unique test bed to study Human-Earth interaction in the Anthropocene. As an example, numerous ground collapses are distributed along lineaments whose orientations fit with the main structural directions. This observation highlights the role of conduit played by underground discontinuities, such as faults and fractures. Very rapid underground water circulation explains the appearance of vegetation (Tamarisk) in unexpected places such as the northern tip of the Lisan peninsula and an "aborted" hectometer-scale landslide. The reactivation of a paleo-channel located below a 38 M salt evaporation pond of the Arab Potash Company, Lisan area, Jordan, provides an example for the implementation of an Early warning System. Time series analysis of high and very high resolution satellite images acquired from the 1970s (Corona, Landsat, Spot, and Worldview) indicate major changes in the landscape. An agreement is found between the limits of the paleo-channel revealed by 2011-2012 Worldview images and Corona photographs acquired in 1973. Landsat MSS data of the 1980s and early 1990s indicated that this channel was reactivated a few years after the emergence of the salt flat around the Lisan peninsula. Radar images (ERS, Envisat, and COSMO-Skymed) acquired from the 1990s are used to map the evolution of the deformation fields associated to the reactivation phenomena. This work shows the need of analyzing very carefully all available data sources acquired prior and during the recession of the lake level before the development of any kind of industrial activities over the recently emerged lands. This research also underlines the necessity to integrate surface and subsurface observations to develop an efficient Early Warning System to live with the Dead Sea geo-hazards.

Hydrogeological perturbations along the Dead Sea coast revealed by submarine sinkholes, Lisan and Ghor al Haditha, Jordan

NASA Astrophysics Data System (ADS)

Closson, D.; Abou Karaki, N.; Milisavljevic, N.; Pasquali, P.; Holecz, F.; Bouaraba, A.

2012-04-01

For several decades, surface water and groundwater located in the closed Dead Sea basin experience excessive exploitation. In fifty years, the level of the terminal lake has fallen by about 30 meters and its surface shrunk by one third. The coastal zone is the one that best shows the stigma of the general environmental degradation. Among these are the sinkholes, landslides and subsidence. For years, these phenomena are relatively well documented, particularly sinkholes and subsidence. Over the past five years, field observations combined with ground deformations measurements by radar interferometric stacking techniques have shown that the intensity (size, frequency) of the collapses is increasing in the most affected part of the southern Dead Sea area. The zones of the dried up Lynch Strait, the Lisan peninsula and Ghor Al Haditha in Jordan seem the most affected. Very high resolution (0.5 to 2 m) GeoEye satellite images have shown that many sinkholes also formed below the level of the Dead Sea. The water transparency allows observations up to several meters deep. These data contribute to the validation of the models developed in connection with the deformation of the fresh/saline water interface due to an imbalance always more pronounced between the levels of the surrounding groundwaters and of the terminal lake.

Age depth model construction of the upper section of ICDP Dead Sea Deep Drilling Project based on the high-resolution 14C dating

NASA Astrophysics Data System (ADS)

Kitagawa, H.; Nakamura, T.; Neugebauer, I.; Schwab, M. J.; Brauer, A.; Goldstein, S. L.; Stein, M.

2014-12-01

To reconstruct environmental, climatic and tectonic histories of the Levant, a deep drilling has been accomplished in the northern basin of the Dead Sea during the fall winter of 2010-2011 by the Dead Sea Deep Drilling Project (DSDDP) in the framework of the ICDP program. The sediment cores from site 5017-1 (water depth of ~300 m) recorded the paleoenvironmental and paleohydrological changes in the Dead Sea and the Levant during the last two glacial-interglacial cycles (Neugebauer et al., QSR in press). To provide precise timing of sedimentological - limnological events in the lake and its watershed, and more critically the relative timing of these events, radiocarbon dating of >70 well-preserved terrestrial plants and some carbonate deposits from the upper 150 m long section of the sediment core were performed. Based on the high-resolution radiocarbon dating, a statistical age-depth model was constructed with assumptions on the deposition condition and the radiocarbon age offset of carbonate samples. We discuss the practicality and the limitation of the age-depth model toward interpreting the high-resolution records of environmental, climatic and tectonic events recorded in the long sediment cores from site 5017-1.

Uncinariasis in northern fur seal and California sea lion pups from California.

PubMed

Lyons, E T; DeLong, R L; Melin, S R; Tolliver, S C

1997-10-01

Northern fur seal (Callorhinus ursinus) (n = 25) and California sea lion (Zalophus californianus) (n = 53) pups, found dead on rookeries on San Miguel Island (California, USA), were examined for adult Uncinaria spp. Prevalence of these nematodes was 96% in fur seal pups and 100% in sea lion pups. Mean intensity of Uncinaria spp. per infected pup was 643 in fur seals and 1,284 in sea lions. Eggs of Uncinaria spp. from dead sea lion pups underwent embryonation in an incubator; development to the free-living third stage larva occurred within the egg. This study provided some specific information on hookworm infections in northern fur seal and California sea lion pups on San Miguel Island. High prevalence rate of Uncinaria spp. in both species of pinnipeds was documented and much higher numbers (2X) of hookworms were present in sea lion than fur seal pups.

Potential Evaporite Biomarkers from the Dead Sea

NASA Technical Reports Server (NTRS)

Morris, Penny A.; Wentworth, Susan J.; Thomas-Keprta, Kathie; Allen, Carlton C.; McKay, David S.

2001-01-01

The Dead Sea is located on the northern branch of the African-Levant Rift systems. The rift system, according to one model, was formed by a series of strike slip faults, initially forming approximately two million years ago. The Dead Sea is an evaporite basin that receives freshwater from springs and from the Jordan River. The Dead Sea is different from other evaporite basins, such as the Great Salt Lake, in that it possesses high concentrations of magnesium and has an average pH of 6.1. The dominant cation in the Great Salt Lake is sodium, and the pH is 7.7. Calcium concentrations are also higher in the Dead Sea than in the Great Salt Lake. Both basins are similar in that the dominant anion is chlorine and the salinity levels are approximately 20 %. Other common cations that have been identified from the waters of the Dead Sea and the Great Salt Lake include sodium and potassium. A variety of Archea, Bacteria, and a single genus of a green algal, Dunaliella, has been described from the Dead Sea. Earlier studies concentrated on microbial identification and analysis of their unique physiology that allows them to survive in this type of extreme environment. Potential microbial fossilization processes, microbial fossils, and the metallic ions associated with fossilization have not been studied thoroughly. The present study is restricted to identifying probable microbial morphologies and associated metallic ions. XRD (X Ray Diffraction) analysis indicates the presence of halite, quartz, and orthoclase feldspar. In addition to these minerals, other workers have reported potassium chloride, magnesium bromide, magnesium chloride, calcium chloride, and calcium sulfate. Halite, calcium sulfate, and orthoclase were examined in this report for the presence of microbes, microbially induced deposits or microbial alteration. Neither the gypsum nor the orthoclase surfaces possesses any obvious indications of microbial life or fossilization. The sand-sized orthoclase particles are weathered with 122 extensive fan-shaped mineral deposits. The gypsum deposits are associated with halite minerals and also exhibit extensive weathering. Halite minerals represent the only substrates that have probable rod-shaped microbial structures with long, filamentous, apical extensions. EDS (energy dispersive x-ray) analysis of the putative microbes indicates elevated calcium levels that are enriched with magnesium. The rod-shaped structures exhibit possible fossilization stages. Rhombohedralshaped minerals of magnesium-enriched calcium carbonate are deposited on the microbial surfaces, and eventually coat the entire microbial surface. The sodium chloride continues to crystallize on nearby halite surface and even crystallizes on the fossilized microbial remains. The putative fossils are found exclusively on halite surfaces, and all contained elevated levels of calcium magnesium cations. Both of these metallic cations are associated with microbial activity and fossilization. Their morphological diversity is low in comparison with the reported living Dead Sea microbial population. If we examine the fossil record for multicellular organisms, fossilization rates are lower for soft-bodied organisms than for those possessing hard parts, i.e. shells, bones. For example, smaller, single celled organisms would have a smaller chance of fossilization; their fossilized shapes could be mistaken for abiotic products. Another consideration is that dead organisms in the water column are probably utilized as a food source by other microbes before fossilization processes are completed. This may be an important consideration as we attempt to model and interpret ancient microbial environments either on Earth or on Mars.

An indicator-based evaluation of Black Sea food web dynamics during 1960-2000

NASA Astrophysics Data System (ADS)

Akoglu, Ekin; Salihoglu, Baris; Libralato, Simone; Oguz, Temel; Solidoro, Cosimo

2014-06-01

Four Ecopath mass-balance models were implemented for evaluating the structure and function of the Black Sea ecosystem using several ecological indicators during four distinctive periods (1960s, 1980-1987, 1988-1994 and 1995-2000). The results exemplify how the Black Sea ecosystem structure started to change after the 1960s as a result of a series of trophic transformations, i.e., shifts in the energy flow pathways through the food web. These transformations were initiated by anthropogenic factors, such as eutrophication and overfishing, that led to the transfer of large quantities of energy to the trophic dead-end species, which had no natural predators in the ecosystem, i.e., jellyfish whose biomass increased from 0.03 g C m- 2 in 1960-1969 to 0.933 g C m- 2 in 1988-1994. Concurrently, an alternative short pathway for energy transfer was formed that converted significant amounts of system production back to detritus. This decreased the transfer efficiency of energy flow from the primary producers to the higher trophic levels from 9% in the 1960s to 3% between 1980 and 1987. We conclude that the anchovy stock collapse and successful establishment of the alien comb-jelly Mnemiopsis in 1989 were rooted in the trophic interactions in the food web, all of which were exacerbated because of the long-term establishment of a combination of anthropogenic stressors.

Multi-Spectral Digital Imaging of Dead Sea Scrolls and Other Ancient Documents

NASA Technical Reports Server (NTRS)

Bearman, Gregory; Zuckerman, Bruce; Zuckerman, Ken; Chiu, Joseph

1993-01-01

It is well known that the Dead Sea scrolls and similar soft media texts are often difficult to read due to the inability of the epigrapher to distinguish the black ink with which they were written from the aged, blacked parchment on which they were inscribed. While considerable success has been achieved in enhancing the readability of these texts through infrared photography, this technique-as conventionally applied today-has distinct limitations.

Crustal Deformation across the Jericho Valley Section of the Dead Sea Fault as Resolved by Detailed Field and Geodetic Observations

NASA Astrophysics Data System (ADS)

Hamiel, Yariv; Piatibratova, Oksana; Mizrahi, Yaakov; Nahmias, Yoav; Sagy, Amir

2018-04-01

Detailed field and geodetic observations of crustal deformation across the Jericho Fault section of the Dead Sea Fault are presented. New field observations reveal several slip episodes that rupture the surface, consist with strike slip and extensional deformation along a fault zone width of about 200 m. Using dense Global Positioning System measurements, we obtain the velocities of new stations across the fault. We find that this section is locked for strike-slip motion with a locking depth of 16.6 ± 7.8 km and a slip rate of 4.8 ± 0.7 mm/year. The Global Positioning System measurements also indicate asymmetrical extension at shallow depths of the Jericho Fault section, between 0.3 and 3 km. Finally, our results suggest the vast majority of the sinistral slip along the Dead Sea Fault in southern Jorden Valley is accommodated by the Jericho Fault section.

Correlation between the silica concentration and the orifice temperature in the warm springs along the jordan-dead sea rift valley

USGS Publications Warehouse

Levitte, D.; Eckstein, Y.

1978-01-01

Analysis of twenty-one thermal springs emerging along the Jordan-Dead Sea Rift Valley in Israel indicates a very good correlation between the concentration of dissolved silica and the temperature of the spring orifice. Dissolution of quartz was identified as the apparent source of the silica in the water. Application of the silica geothermometer for mixed systems suggests that the springs in the Tiberias Lake Basin are supplied with hot water from deep reservoir (or reservoirs) at a temperature of 115??C (239??F). The same temperature was postulated earlier by the application of the Na-K-Ca hydro-geothermometer to a group of thermal springs in the same basin. The temperature of the reservoir supplying hot brines to the springs emerging along the western shore of the Dead Sea is estimated at 90??C (194??F).

Space Radar Image of Jerusalem and the Dead Sea

NASA Technical Reports Server (NTRS)

1994-01-01

This space radar image shows the area surrounding the Dead Sea along the West Bank between Israel and Jordan. This region is of major cultural and historical importance to millions of Muslims, Jews and Christians who consider it the Holy Land. The yellow area at the top of the image is the city of Jericho. A portion of the Dead Sea is shown as the large black area at the top right side of the image. The Jordan River is the white line at the top of the image which flows into the Dead Sea. Jerusalem, which lies in the Judaean Hill Country, is the bright, yellowish area shown along the left center of the image. Just below and to the right of Jerusalem is the town of Bethlehem. The city of Hebron is the white, yellowish area near the bottom of the image. The area around Jerusalem has a history of more than 2,000 years of settlement and scientists are hoping to use these data to unveil more about this region's past. The Jordan River Valley is part of an active fault and rift system that extends from southern Turkey and connects with the east African rift zone. This fault system has produced major earthquakes throughout history and some scientists theorize that an earthquake may have caused the fall of Jericho's walls. The Dead Sea basin is formed by active earthquake faulting and contains the lowest place on the Earth's surface at about 400 meters (1,300 feet) below sea level. It was in caves along the northern shore of the Dead Sea that the Dead Sea Scrolls were found in 1947. The blue and green areas are generally regions of undeveloped hills and the dark green areas are the smooth lowlands of the Jordan River valley. This image is 73 kilometers by 45 kilometers (45 miles by 28 miles) and is centered at 31.7 degrees north latitude, 35.4 degrees east longitude. North is toward the upper left. The colors are assigned to different radar frequencies and polarizations as follows: red is L-band, horizontally transmitted and vertically received; green is L-band, horizontally transmitted and horizontally received; and blue is C-band, horizontally transmitted and vertically received. The image was acquired by the Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) on October 3, 1994 onboard the space shuttle Endeavour. SIR-C/X-SAR, a joint mission of the German, Italian and United States space agencies, is part of NASA's Mission to Planet Earth. Each flight of SIR-C/X-SAR collected data at more than 400 sites around the globe. The science team is using images like this one to help answer various scientific questions about the condition of ecosystems, the extent of snow and ice packs, geologic activity such as volcanoes and earthquakes, and measurement of ocean waves and currents.

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

Monson, D.H.; Ballachey, B.

Age distribution of sea otters (Enhydra lutris) found dead on beaches in western Prince William Sound Alaska, from 1976 to 1984, were compared to those of sea otters found dead from 1989 to 1993, following the Exxon Valdez oil spill. The age distribution of sea otters recovered in western Prince William Sound prior to the spill was bimodal and composed of primarily young and old animals. The high proportion of prime-age otters recovered immediately following the spill indicates significant losses occurred within a segment of the population which normally experiences very low mortality. The high proportion of prime-age otters recoveredmore » in 1990-1991 may be evidence of a prolonged, spill-related effect on the western Prince William Sound sea otter population.« less

Relationships between lake-level changes and water and salt budgets in the Dead Sea during extreme aridities in the Eastern Mediterranean

NASA Astrophysics Data System (ADS)

Kiro, Yael; Goldstein, Steven L.; Garcia-Veigas, Javier; Levy, Elan; Kushnir, Yochanan; Stein, Mordechai; Lazar, Boaz

2017-04-01

Thick halite intervals recovered by the Dead Sea Deep Drilling Project cores show evidence for severely arid climatic conditions in the eastern Mediterranean during the last three interglacials. In particular, the core interval corresponding to the peak of the last interglacial (Marine Isotope Stage 5e or MIS 5e) contains ∼30 m of salt over 85 m of core length, making this the driest known period in that region during the late Quaternary. This study reconstructs Dead Sea lake levels during the salt deposition intervals, based on water and salt budgets derived from the Dead Sea brine composition and the amount of salt in the core. Modern water and salt budgets indicate that halite precipitates only during declining lake levels, while the amount of dissolved Na+ and Cl- accumulates during wetter intervals. Based on the compositions of Dead Sea brines from pore waters and halite fluid inclusions, we estimate that ∼12-16 cm of halite precipitated per meter of lake-level drop. During periods of halite precipitation, the Mg2+ concentration increases and the Na+/Cl- ratio decreases in the lake. Our calculations indicate major lake-level drops of ∼170 m from lake levels of 320 and 310 m below sea level (mbsl) down to lake levels of ∼490 and ∼480 mbsl, during MIS 5e and the Holocene, respectively. These lake levels are much lower than typical interglacial lake levels of around 400 mbsl. These lake-level drops occurred as a result of major decreases in average fresh water runoff, to ∼40% of the modern value (pre-1964, before major fresh water diversions), reflecting severe droughts during which annual precipitation in Jerusalem was lower than 350 mm/y, compared to ∼600 mm/y today. Nevertheless, even during salt intervals, the changes in halite facies and the occurrence of alternating periods of halite and detritus in the Dead Sea core stratigraphy reflect fluctuations between drier and wetter conditions around our estimated average. The halite intervals include periods that are richer and poorer in halite, indicating (based on the sedimentation rate) that severe dry conditions with water availability as low as ∼20% of the present day, continued for periods of decades to centuries, and fluctuated with wetter conditions that spanned centuries to millennia when water availability was ∼50-100% of the present day. These conclusions have potential implications for the coming decades, as climate models predict greater aridity in the region.

Monitoring and modeling of sinkholes affecting the Jordanian coast of the Dead Sea through satellite interferometric techniques

NASA Astrophysics Data System (ADS)

Tessari, Giulia; Pasquali, Paolo; Floris, Mario

2016-04-01

Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques have been applied to investigate sinkholes affecting the Jordanian coast of the Dead Sea. The Dead Sea is a hyper saline terminal lake located in a pull-apart basin. Most of the area is characterized by highly karstic and fractured rock formations that are connected with faults. Karstic conduits extend from the land into the sea. Since the 1960s, the Dead Sea level is dropping at an increasing rate: from about 60 cm/yr in the 1970s up to 1 m/yr in the 2000s. From about the mid-1980s, sinkholes appeared more and more frequently over and around the emerged mudflats and salt flats. Strong subsidence and landslides also affect some segments of the coast. Nowadays, several thousands of sinkholes attest that the degradation of the Dead Sea coast is worsening. Deformation analysis has been focused on the Ghor Al Haditha area, located in the South-Eastern part of the lake coast. SAR data acquired by three different sensors, ERS, ENVISAT and COSMO- SkyMed have been analysed. 70 ERS images from 1992 to 2009 and 30 ENVISAT images from 2003 to 2010 have been processed. SBAS technique has been applied to define surface velocity and displacement maps. Results obtained from the SBAS technique, applied to ERS and Envisat data, highlight a diffuse subsiding of the entire Eastern coast of the Dead Sea. It was not possible to detect single sinkholes because of the resolution of these sensors (25m2) and the small size of each punctual event that is generally varying from a few meters to a hundred meters diameter. Furthermore, SBAS has been applied to 23 COSMO-SkyMed SAR satellite images from December 2011 to May 2013. The high resolution of these data (3m x 3m) and the short revisiting time allowed precise information of the displacement of punctual sinkholes beyond the overall subsidence of the coast. A specific sinkhole has been identified in order to understand its temporal evolution. The considered phenomenon reached a total displacement of around 120 mm in 18 months in its central part. On the basis of the results from DInSAR processing, a simplified analytical model has been implemented. Vertical and horizontal components of the surface displacement field obtained from analysis of SAR images have been used as input data to derive geometric parameters of the source and in particular to estimate the volumetric strain of the phenomenon. Position, dimension and mechanism have been obtained.

North Atlantic influence on 19th-20th century rainfall in the Dead Sea watershed, teleconnections with the Sahel, and implication for Holocene climate fluctuations

NASA Astrophysics Data System (ADS)

Kushnir, Yochanan; Stein, Mordechai

2010-12-01

The importance of understanding processes that govern the hydroclimate of the Mediterranean Basin is highlighted by the projected significant drying of the region in response to the increase in greenhouse gas concentrations. Here we study the long-term hydroclimatic variability of the central Levant region, situated in the eastern boundary of the Basin, as reveled by instrumental observations and the Holocene record of Dead Sea level variations. Observations of 19th and 20th century precipitation in the Dead Sea watershed region display a multidecadal, anti-phase relationship to North Atlantic (NAtl) sea surface temperature (SST) variability, such that when the NAtl is relatively cold, Jerusalem experiences higher than normal precipitation and vice versa. This association is underlined by a negative correlation to precipitation in the sub-Saharan Sahel and a positive correlation to precipitation in western North America, areas that are also affected by multidecadal NAtl SST variability. These observations are consistent with a broad range of Holocene hydroclimatic fluctuations from the epochal, to the millennial and centennial time scales, as displayed by the Dead Sea lake level, by lake levels in the Sahel, and by direct and indirect proxy indicators of NAtl SSTs. On the epochal time scale, the gradual cooling of NAtl SSTs throughout the Holocene in response to precession-driven reduction of summer insolation is associated with previously well-studied wet-to-dry transition in the Sahel and with a general increase in Dead Sea lake levels from low stands after the Younger Dryas to higher stands in the mid- to late-Holocene. On the millennial and centennial time scales there is also evidence for an anti-phase relationship between Holocene variations in the Dead Sea and Sahelian lake levels and with proxy indicators of NAtl SSTs. However the records are punctuated by abrupt lake-level drops, which appear to be in-phase and which occur during previously documented abrupt major cooling events in the Northern Hemisphere. We propose that the mechanisms by which NAtl SSTs affect precipitation in the central Levant is related to the tendency for high (low) pressure anomalies to persist over the eastern North Atlantic/Western Mediterranean region when the Basin is cold (warm). This, in turn, affects the likelihood of cold air outbreaks and cyclogenesis in the Eastern Mediterranean and, consequently, rainfall in the central Levant region. Depending on its phase, this natural mechanism can alleviate or exacerbate the anthropogenic impact on the regions' hydroclimatic future.

Increased sedimentation following the Neolithic Revolution in the Southern Levant

NASA Astrophysics Data System (ADS)

Lu, Yin; Waldmann, Nicolas; Nadel, Dani; Marco, Shmuel

2017-05-01

The Dead Sea drainage basin offers a rare combination of well-documented substantial climate change, intense tectonics and abundant archaeological evidence for past human activity in the Southern Levant. It serves as a natural laboratory for understanding how sedimentation rates in a deep basin are related to climate change, tectonics, and anthropogenic impacts on the landscape. Here we show how basin-wide erosion rates are recorded by thicknesses of rhythmic detritus laminae and clastic sediment accumulation rates in a long core retrieved by the Dead Sea Deep Drilling Project in the Dead Sea depocenter. During the last 11.5 kyr the average detrital accumulation rate is 3-4 times that during the last two glacial cycles (MIS 7c-2), and the average thickness of detritus laminae in the last 11.6 kyr is 4.5 times that between 21.7 and 11.6 ka, implying an increased erosion rate on the surrounding slopes during the Holocene. We estimate that this intensified erosion is incompatible with tectonic and climatic regimes during the corresponding time interval and further propose a close association with the Neolithic Revolution in the Levant (beginning at 11.5 ka). We thus suggest that human impact on the landscape was the primary driver causing the intensified erosion and that the Dead Sea sedimentary record serves as a reliable recorder of this impact since the Neolithic Revolution.

Geometry and subsidence history of the Dead Sea basin: A case for fluid-induced mid-crustal shear zone?

USGS Publications Warehouse

ten Brink, Uri S.; Flores, C.H.

2012-01-01

Pull-apart basins are narrow zones of crustal extension bounded by strike-slip faults that can serve as analogs to the early stages of crustal rifting. We use seismic tomography, 2-D ray tracing, gravity modeling, and subsidence analysis to study crustal extension of the Dead Sea basin (DSB), a large and long-lived pull-apart basin along the Dead Sea transform (DST). The basin gradually shallows southward for 50 km from the only significant transverse normal fault. Stratigraphic relationships there indicate basin elongation with time. The basin is deepest (8-8.5 km) and widest (???15 km) under the Lisan about 40 km north of the transverse fault. Farther north, basin depth is ambiguous, but is 3 km deep immediately north of the lake. The underlying pre-basin sedimentary layer thickens gradually from 2 to 3 km under the southern edge of the DSB to 3-4 km under the northern end of the lake and 5-6 km farther north. Crystalline basement is ???11 km deep under the deepest part of the basin. The upper crust under the basin has lower P wave velocity than in the surrounding regions, which is interpreted to reflect elevated pore fluids there. Within data resolution, the lower crust below ???18 km and the Moho are not affected by basin development. The subsidence rate was several hundreds of m/m.y. since the development of the DST ???17 Ma, similar to other basins along the DST, but subsidence rate has accelerated by an order of magnitude during the Pleistocene, which allowed the accumulation of 4 km of sediment. We propose that the rapid subsidence and perhaps elongation of the DSB are due to the development of inter-connected mid-crustal ductile shear zones caused by alteration of feldspar to muscovite in the presence of pore fluids. This alteration resulted in a significant strength decrease and viscous creep. We propose a similar cause to the enigmatic rapid subsidence of the North Sea at the onset the North Atlantic mantle plume. Thus, we propose that aqueous fluid flux into a slowly extending continental crust can cause rapid basin subsidence that may be erroneously interpreted as an increased rate of tectonic activity. Copyright 2012 by the American Geophysical Union.

Climate change and dead zones.

PubMed

Altieri, Andrew H; Gedan, Keryn B

2015-04-01

Estuaries and coastal seas provide valuable ecosystem services but are particularly vulnerable to the co-occurring threats of climate change and oxygen-depleted dead zones. We analyzed the severity of climate change predicted for existing dead zones, and found that 94% of dead zones are in regions that will experience at least a 2 °C temperature increase by the end of the century. We then reviewed how climate change will exacerbate hypoxic conditions through oceanographic, ecological, and physiological processes. We found evidence that suggests numerous climate variables including temperature, ocean acidification, sea-level rise, precipitation, wind, and storm patterns will affect dead zones, and that each of those factors has the potential to act through multiple pathways on both oxygen availability and ecological responses to hypoxia. Given the variety and strength of the mechanisms by which climate change exacerbates hypoxia, and the rates at which climate is changing, we posit that climate change variables are contributing to the dead zone epidemic by acting synergistically with one another and with recognized anthropogenic triggers of hypoxia including eutrophication. This suggests that a multidisciplinary, integrated approach that considers the full range of climate variables is needed to track and potentially reverse the spread of dead zones. © 2014 John Wiley & Sons Ltd.

Dead Sea pollen provides new insights into the paleoenvironment of the southern Levant during MIS 6-5

NASA Astrophysics Data System (ADS)

Chen, Chunzhu; Litt, Thomas

2018-05-01

The paleoclimate of the southern Levant, especially during the last interglacial (LIG), is still under debate. Reliable paleovegetation information for this period, as independent evidence to the paleoenvironment, was still missing. In this study, we present a high-resolution pollen record encompassing 147-89 ka from the Dead Sea deep drilling core 5017-1A. The sediment profile is marked by alternations of laminated marl deposits and thick massive halite, indicating lake-level fluctuations. The pollen record suggests that steppe and desert components predominated in the Dead Sea surroundings during the whole investigated interval. The late penultimate glacial (147.3-130.9 ka) and early last glacial (115.5-89.1 ka) were cool and relatively dry, with sub-humid conditions confined to the mountains that sustained moderate amounts of deciduous oaks. Prior to the LIG optimum, a prevalence of desert components and a concomitant increase in frost-sensitive pistachio trees demonstrate the occurrence of an arid initial warming phase (130.9-124.2 ka). The LIG optimum (124.2 ka-115.5 ka) was initiated by an abrupt grass expansion that was followed by a rapid spread of woodlands in the mountains due to increased moisture availability. The remarkable sclerophyllous expansion points to a strong seasonal moisture deficit. These results contradict previous Dead Sea lake-level investigations that suggested pluvial glacials and a warm, dry LIG in the southern Levant. Prominent discrepancies between vegetation and Dead Sea lake stands are also registered at 128-115 ka, and the potential causes are discussed. In particular, while the pollen spectra mirror increased effective moisture during the LIG optimum, the massive halite deposition is indicative of an extremely low lake level. Given that the climate amelioration triggered the migration of early modern humans to the southern Levant, we speculate that the diverse ecosystems in the region provided great potential for their residence. Across the eastern Mediterranean region, an analogous vegetation succession pattern is observed.

International Conference on Deformation, Yield and Fracture of Polymers (9th) Held in Cambridge, UK on 11-14 April, 1994. Conference Papers

DTIC Science & Technology

1994-01-01

microplasticity and relaxations in polymers using a laser interferometer NN Peschanskaya, PN Yakushev, AB Sinani and VA Bershtein (Ioffe Physical-Technical...Medicine, London, UK) P29 Toughening mechanism of flame-retarded plastics L Utevskii, I Finberg, E Reznik and M Muskatel (Dead Sea Bromine group, Beer...Dead Sea Bromine Group, Beer Sheva, Israel) P31 Stress-relaxation due to environmental effects on polypropylene and fiber reinforced polyester E Gutman

Haloarcula marismortui (Volcani) sp. nov., nom. rev., an extremely halophilic bacterium from the Dead Sea

NASA Technical Reports Server (NTRS)

Oren, A.; Ginzburg, M.; Ginzburg, B. Z.; Hochstein, L. I.; Volcani, B. E.

1990-01-01

An extremely halophilic red archaebacterium isolated from the Dead Sea (Ginzburg et al., J. Gen. Physiol. 55: 187-207, 1970) belongs to the genus Haloarcula and differs sufficiently from the previously described species of the genus to be designated a new species; we propose the name Haloarcula marismortui (Volcani) sp. nov., nom. rev. because of the close resemblance of this organism to "Halobacterium marismortui," which was first described by Volcani in 1940. The type strain is strain ATCC 43049.

Microbial community analysis of the hypersaline water of the Dead Sea using high-throughput amplicon sequencing.

PubMed

Jacob, Jacob H; Hussein, Emad I; Shakhatreh, Muhamad Ali K; Cornelison, Christopher T

2017-10-01

Amplicon sequencing using next-generation technology (bTEFAP ® ) has been utilized in describing the diversity of Dead Sea microbiota. The investigated area is a well-known salt lake in the western part of Jordan found in the lowest geographical location in the world (more than 420 m below sea level) and characterized by extreme salinity (approximately, 34%) in addition to other extreme conditions (low pH, unique ionic composition different from sea water). DNA was extracted from Dead Sea water. A total of 314,310 small subunit RNA (SSU rRNA) sequences were parsed, and 288,452 sequences were then clustered. For alpha diversity analysis, sample was rarefied to 3,000 sequences. The Shannon-Wiener index curve plot reached a plateau at approximately 3,000 sequences indicating that sequencing depth was sufficient to capture the full scope of microbial diversity. Archaea was found to be dominating the sequences (52%), whereas Bacteria constitute 45% of the sequences. Altogether, prokaryotic sequences (which constitute 97% of all sequences) were found to predominate. The findings expand on previous studies by using high-throughput amplicon sequencing to describe the microbial community in an environment which in recent years has been shown to hide some interesting diversity. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Chlorophyll catalyse the photo-transformation of carcinogenic benzo[a]pyrene in water

PubMed Central

Luo, Lijuan; Lai, Xueying; Chen, Baowei; Lin, Li; Fang, Ling; Tam, Nora F. Y.; Luan, Tiangang

2015-01-01

Algal blooms cause great damage to water quality and aquaculture. However, this study showed that dead algal cells and chlorophyll could accelerate the photo-transformation of benzo[a]pyrene (BaP), a ubiquitous and persistent pollutant with potently mutagenic and carcinogenic toxicities, under visible light irradiation. Chlorophyll was found to be the major active substance in dead algal cells, and generated a high level of singlet oxygen to catalyse the photo-transformation of BaP. According to various BaP metabolites formed, the degradation mechanism was proposed as that chlorophyll in dead algal cells photo-oxidized BaP to quinones via photocatalytic generation of singlet oxygen. The results provided a good insight into the role of chlorophyll in the photo-transformation of organic contaminants and could be a possible remediation strategy of organic pollutants in natural environment. PMID:26239357

The stereoisomeric composition of phytanyl chains in lipids of Dead Sea sediments

NASA Technical Reports Server (NTRS)

Anderson, R.; Kates, M.; Baedecker, M. J.; Kaplan, I. R.; Ackman, R. G.

1977-01-01

Lipid extracts from five recent Dead Sea sediments were analyzed for isoprenoid compounds and the following were isolated: free and phospholipid-bound di-O-phytanylglycerol, free phytanol and free and esterified phytanic acid. The phytanyl groups of the diether and the free phytanol were oxidized to the corresponding phytanic acid; the stereoisomeric composition of the derived phytanic acids as well as of the ester-bound phytanic acid was determined by open-tubular gas-liquid chromatography of the corresponding methyl esters on butanediolsuccinate polyester. Only the 3R, 7R, 11R-isomer of phytanic acid was detected in each of the phytanate samples, indicating that these phytanyl chains in the Dead Sea sediments are most likely derived from extremely halophilic bacteria rather than from phytol of chlorophyll origin. These findings also provide further evidence that the mixtures of RRR and SRR-phytanic acids previously isolated from organic-rich shales were most likely derived from the phytyl chain in chlorophyll.

The stereoisomeric composition of phytanyl chains in lipids of Dead Sea sediments

USGS Publications Warehouse

Anderson, R.; Kates, M.; Baedecker, M.J.; Kaplan, I.R.; Ackman, R.G.

1977-01-01

Lipid extracts from five recent Dead Sea sediments were analyzed for isoprenoid compounds and the following were isolated: free and phospholipid-bound di-O-phytanylglycerol, free phytanol and free and esterifled phytanic acid. The phytanyl groups of the diether and the free phytanol were oxidized to the corresponding phytanic acid; the stereoisomeric composition of the derived phytanic acids as well as of the ester-bound phytanic acid was determined by open-tubular gas-liquid chromatography of the corresponding methyl esters on butanediolsuccinate polyester. Only the 3R,7R,11R-isomer of phytanic acid was detected in each of the phytanate samples, indicating that these phytanyl chains in the Dead Sea sediments are most likely derived from extremely halophilic bacteria rather than from phytol of chlorophyll origin. These findings also provide further evidence that the mixtures of RRR and SRR-phytanic acids previously isolated from organic-rich shales were most likely derived from the phytyl chain in chlorophyll. ?? 1977.

Scale-free distribution of Dead Sea sinkholes: Observations and modeling

NASA Astrophysics Data System (ADS)

Yizhaq, H.; Ish-Shalom, C.; Raz, E.; Ashkenazy, Y.

2017-05-01

There are currently more than 5500 sinkholes along the Dead Sea in Israel. These were formed due to the dissolution of subsurface salt layers as a result of the replacement of hypersaline groundwater by fresh brackish groundwater. This process has been associated with a sharp decline in the Dead Sea water level, currently more than 1 m/yr, resulting in a lower water table that has allowed the intrusion of fresher brackish water. We studied the distribution of the sinkhole sizes and found that it is scale free with a power law exponent close to 2. We constructed a stochastic cellular automata model to understand the observed scale-free behavior and the growth of the sinkhole area in time. The model consists of a lower salt layer and an upper soil layer in which cavities that develop in the lower layer lead to collapses in the upper layer. The model reproduces the observed power law distribution without involving the threshold behavior commonly associated with criticality.

Wind systems the driving force of evaporation at the Dead Sea

NASA Astrophysics Data System (ADS)

Metzger, Jutta; Corsmeier, Ulrich; Alpert, Pinhas

2017-04-01

The Dead Sea is a unique place on earth. It is located in the Eastern Mediterranean at the lowest point of the Jordan Rift valley and its water level is currently at 429 m below mean sea level. The region is located in a transition zone of semi-arid to arid climate conditions and endangered by severe environmental problems, especially the rapid lake level decline (>1m/year), causing the shifting of fresh/saline groundwater interfaces and the drying up of the lake. Two key features are relevant for these environmental changes: the evaporation from the water surface and its driving mechanisms. The main driver of evaporation at the Dead Sea is the wind velocity and hence the governing wind systems with different scales in space and time. In the framework of the Virtual Institute DEad SEa Research Venue (DESERVE) an extensive field campaign was conducted to study the governing wind systems in the valley and the energy balance of the water and land surface simultaneously. The combination of several in-situ and remote sensing instruments allowed temporally and spatially high-resolution measurements to investigate the frequency of occurrence of the wind systems, their three-dimensional structure, associated wind velocities and their impact on evaporation. The characteristics of the three local wind systems governing the valley's wind field, as well as their impact on evaporation, will be presented. Mostly decoupled from the large scale flow a local lake breeze determines the conditions during the day. Strong downslope winds drive the evaporation in the afternoon, and down valley flows with wind velocities of over 10 m s-1 dominate during the night causing unusually high evaporation rates after sunset.

Abrupt aridities in the Levant-Sahel linked with solar activities

NASA Astrophysics Data System (ADS)

Stein, M.; Kushnir, Y.

2012-04-01

Observations of 19th and 20th century precipitation in the Dead Sea watershed region display a multidecadal, anti-phase relationship to North Atlantic (NAtl) sea surface temperature (SST) variability, such that when the NAtl is relatively cold, Jerusalem experiences higher than normal precipitation and vice versa. This association is underlined by a negative correlation to precipitation in the sub-Saharan Sahel and a positive correlation to precipitation in western North America, areas that are also affected by multidecadal NAtl SST variability. These observations are consistent with broad range of Holocene hydroclimatic fluctuations from the epochal, to the millennial and centennial time scales, as displayed by the Dead Sea and Sahelian lake levels and by direct and indirect proxy indicators of NAtl SSTs. On the epochal time scale, the gradual cooling of NAtl SSTs throughout the Holocene in response to precession-driven reduction of summer insolation is associated with previously well-studied wet-to-dry transition in the Sahel and with a general increase in Dead Sea lake levels from low stands after the Younger Dryas to higher stands in the mid- to late-Holocene. On the millennial and centennial time scales there is also evidence for an antiphase relationship between Holocene variations in the Dead Sea and Sahelian lake levels and with proxy indicators of NAtl SSTs. However, the records are punctuated by abrupt lake-level drops and extensive expansion of the desert belt at ~8.1, 5.7, 3.3 and 1.4 ka cal BP, which appear to be in-phase and which occur during previously documented abrupt major cooling events in the Northern Hemisphere. We link these cooling to solar activity variations that were identified in the North Atlantic IRD and cosmogenic isotopes records.

Investigating Western Dead Sea spring systems and their origin by application of hydrogeochemical patterns

NASA Astrophysics Data System (ADS)

Wilske, Cornelia; Siebert, Christian; Geyer, Stefan; Rödiger, Tino; Merkel, Broder

2013-04-01

One of the ecologic and touristic hot spots along the western Dead Sea shore is the spring system of Ein Feshkha (Enot Zukim), which suffers from a changing environment. Its feeding Cretaceous aquifers are hosted in the western Graben flank of the Jordan-Dead Sea Rift. However, the origin of water and the ratio of influence of the unconsolidated Quaternary Graben fill is a controversial issue. The aim of the study is to combine hydrogeochemical information of the spring waters and the potential source aquifers to characterize and differentiate the groundwater origins, groundwater flow paths and eventually groundwater mixtures. Within this case study, which is embedded in the SMART II project (Sustainable Management of Available Water Resources of the Lower Jordan Valley), the investigation area extends in the Judean Mountains from the vicinity of Ramallah down to Hebron and ends along the north-western shoreline of the Dead Sea. The Cretaceous limestone aquifers of Turonian/Upper Cenomanian and Albian age are widely separated by a clayey aquiclude. That so called Judea Group is underlaid by the Kurnub sandstone aquifer. Mainly due to the development of the Rift, the entire area is intensely folded and crossed by faults. Groundwater recharge takes place in the uplands and the groundwater flow gradient is oriented towards the Valley, where it transgresses into the Quaternary Graben fill. Our hypothesis is that Ein Feshkha springs are fed by groundwater originating in general in the mountain range, which also takes a detour through the Graben fill in the north of the Dead Sea. Groundwater from these aquifers emerges along the coast of the Dead Sea through springs. The methodological approach is to use geogenic and anthropogenic hydrochemical parameters like major- and trace elements, stable isotopes like δ2H, δ18O or δ87Sr and heavy metals. Sampling campaigns were and will be carried out quarterly within one hydrological year to uncover possible seasonal variations. Samples are taken from the different aquifers over the whole investigation area. The first results represent the variability of the groundwater chemistry in terms of their TDS contents and their stable isotope signatures. The measured stable isotope ratios of Strontium, which refer to the geological background, show a differentiation between the groundwater of the main Judean aquifers. In combination with stable isotopes the composition of major- and trace elements including heavy metals improve the aquifer differentiation against the background of changes in geological formations.

5000 yr of paleoseismicity along the southern Dead Sea fault

NASA Astrophysics Data System (ADS)

Klinger, Y.; Le Béon, M.; Al-Qaryouti, M.

2015-07-01

The 1000-km-long left-lateral Dead Sea fault is a major tectonic structure of the oriental Mediterranean basin, bounding the Arabian Plate to the west. The fault is located in a region with an exceptionally long and rich historical record, allowing to document historical seismicity catalogues with unprecedented level of details. However, if the earthquake time series is well documented, location and lateral extent of past earthquakes remain often difficult to establish, if only based on historical testimonies. We excavated a palaeoseismic trench in a site located in a kilometre-size extensional jog, south of the Dead Sea, in the Wadi Araba. Based on the stratigraphy exposed in the trench, we present evidence for nine earthquakes that produced surface ruptures during a time period spanning 5000 yr. Abundance of datable material allows us to tie the five most recent events to historical earthquakes with little ambiguities, and to constrain the possible location of these historical earthquakes. The events identified at our site are the 1458 C.E., 1212 C.E., 1068 C.E., one event during the 8th century crisis, and the 363 C.E. earthquake. Four other events are also identified, which correlation with historical events remains more speculative. The magnitude of earthquakes is difficult to assess based on evidence at one site only. The deformation observed in the excavation, however, allows discriminating between two classes of events that produced vertical deformation with one order of amplitude difference, suggesting that we could distinguish earthquakes that started/stopped at our site from earthquakes that potentially ruptured most of the Wadi Araba fault. The time distribution of earthquakes during the past 5000 yr is uneven. The early period shows little activity with return interval of ˜500 yr or longer. It is followed by a ˜1500-yr-long period with more frequent events, about every 200 yr. Then, for the past ˜550 yr, the fault has switched back to a quieter mode with no significant earthquake along the entire southern part of the Dead Sea fault, between the Dead Sea and the Gulf of Aqaba. We computed the Coefficient of Variation for our site and three other sites along the Dead Sea fault, south of Lebanon, to compare time distribution of earthquakes at different locations along the fault. With one exception at a site located next to Lake Tiberias, the three other sites are consistent to show some temporal clustering at the scale of few thousands years.

Dead Sea evaporation by eddy covariance measurements vs. aerodynamic, energy budget, Priestley-Taylor, and Penman estimates

NASA Astrophysics Data System (ADS)

Metzger, Jutta; Nied, Manuela; Corsmeier, Ulrich; Kleffmann, Jörg; Kottmeier, Christoph

2018-02-01

The Dead Sea is a terminal lake, located in an arid environment. Evaporation is the key component of the Dead Sea water budget and accounts for the main loss of water. So far, lake evaporation has been determined by indirect methods only and not measured directly. Consequently, the governing factors of evaporation are unknown. For the first time, long-term eddy covariance measurements were performed at the western Dead Sea shore for a period of 1 year by implementing a new concept for onshore lake evaporation measurements. To account for lake evaporation during offshore wind conditions, a robust and reliable multiple regression model was developed using the identified governing factors wind velocity and water vapour pressure deficit. An overall regression coefficient of 0.8 is achieved. The measurements show that the diurnal evaporation cycle is governed by three local wind systems: a lake breeze during daytime, strong downslope winds in the evening, and strong northerly along-valley flows during the night. After sunset, the strong winds cause half-hourly evaporation rates which are up to 100 % higher than during daytime. The median daily evaporation is 4.3 mm d-1 in July and 1.1 mm d-1 in December. The annual evaporation of the water surface at the measurement location was 994±88 mm a-1 from March 2014 until March 2015. Furthermore, the performance of indirect evaporation approaches was tested and compared to the measurements. The aerodynamic approach is applicable for sub-daily and multi-day calculations and attains correlation coefficients between 0.85 and 0.99. For the application of the Bowen ratio energy budget method and the Priestley-Taylor method, measurements of the heat storage term are inevitable on timescales up to 1 month. Otherwise strong seasonal biases occur. The Penman equation was adapted to calculate realistic evaporation, by using an empirically gained linear function for the heat storage term, achieving correlation coefficients between 0.92 and 0.97. In summary, this study introduces a new approach to measure lake evaporation with a station located at the shoreline, which is also transferable to other lakes. It provides the first directly measured Dead Sea evaporation rates as well as applicable methods for evaporation calculation. The first one enables us to further close the Dead Sea water budget, and the latter one enables us to facilitate water management in the region.

Geochemical assessment of hydrocarbon migration phenomena: Case studies from the south-western margin of the Dead Sea Basin

NASA Astrophysics Data System (ADS)

Sokol, Ella; Kozmenko, Olga; Smirnov, Sergey; Sokol, Ivan; Novikova, Sofya; Tomilenko, Anatoliy; Kokh, Svetlana; Ryazanova, Tatyana; Reutsky, Vadim; Bul'bak, Taras; Vapnik, Yevgeny; Deyak, Michail

2014-10-01

Calcite veins with fluid and solid bitumen inclusions have been discovered in the south-western shoulder of the Dead Sea rift within the Masada-Zohar block, where hydrocarbons exist in small commercial gas fields and non-commercial fields of heavy and light oils. The gas-liquid inclusions in calcite are dominated either by methane or CO2, and aqueous inclusions sometimes bear minor dissolved hydrocarbons. The enclosed flake-like solid bitumen matter is a residue of degraded oil, which may be interpreted as “dead carbon”. About 2/3 of this matter is soot-like amorphous carbon and 1/3 consists of n-C8sbnd C18 carboxylic acids and traces of n-alkanes, light dicarboxylic acids, and higher molecular weight (>C20) branched and/or cyclic carboxylic acids. Both bitumen and the host calcites show genetic relationship with mature Maastrichtian chalky source rocks (MCSRs) evident in isotopic compositions (δ13C, δ34S, and δ18O) and in REE + Y patterns. The bitumen precursor may have been heavy sulfur-rich oil which was generated during the burial compaction of the MCSR strata within the subsided blocks of the Dead Sea graben. The δ18O and δ13C values and REE + Y signatures in calcites indicate mixing of deep buried fluids equilibrated with post-mature sediments and meteoric waters. The temperatures of fluid generation according to Mg-Li-geothermometer data range from 55 °С to 90 °С corresponding to the 2.5-4.0 km depths, and largely overlap with the oil window range (60-90 °С) in the Dead Sea rift (Hunt, 1996; Gvirtzman and Stanislavsky, 2000; Buryakovsky et al., 2005). The bitumen-rich vein calcites originated in the course of Late Cenozoic rifting and related deformation, when tectonic stress triggers damaged small hydrocarbon reservoirs in the area, produced pathways, and caused hydrocarbon-bearing fluids to rise to the subsurface; the fluids filled open fractures and crystallized to calcite with entrapped bitumen. The reported results are in good agreement with the existing views of maturation, migration, and accumulation of hydrocarbons, as well as basin fluid transport processes in the Dead Sea area.

NOAA Photo Library - Navigating the Collection

Science.gov Websites

exotic locations such as the People's Republic of China, the Red Sea region, the catacombs of Lima, and boatload of fins, fur, and feathers. Whales, seals, sea lions, sea birds, and also the occasional bird , and Red Sea reefs are found in this collection. Also disturbing images of coral reef bleaching, dead

Contamination status and accumulation profiles of organotins in sea otters (Enhydra lutris) found dead along the coasts of California, Washington, Alaska (USA), and Kamchatka (Russia)

USGS Publications Warehouse

Murata, S.; Takahashi, S.; Agusa, T.; Thomas, N.J.; Kannan, K.; Tanabe, S.

2008-01-01

Organotin compounds (OTs) including mono- to tri-butyltins, -phenyltins, and -octyltins were determined in the liver of adult sea otters (Enhydra lutris) found dead along the coasts of California, Washington, and Alaska in the USA and Kamchatka, Russia. Total concentrations of OTs in sea otters from California ranged from 34 to 4100 ng/g on a wet weight basis. The order of concentrations of OTs in sea otters was total butyltins ??? total octyltins ??? total phenyltins. Elevated concentrations of butyltins (BTs) were found in some otters classified under 'infectious-disease' mortality category. Concentrations of BTs in few of these otters were close to or above the threshold levels for adverse health effects. Total butyltin concentrations decreased significantly in the livers of California sea otters since the 1990s. Based on the concentrations of organotins in sea otters collected from 1992 to 2002, the half-lives of tributyltin and total butyltins in sea otters were estimated to be approximately three years. ?? 2008 Elsevier Ltd. All rights reserved.

[Wood transformation in dead-standing trees in the forest-tundra of Central Siberia].

PubMed

Mukhortova, L V; Kirdianov, A V; Myglan, V S; Guggenberger, G

2009-01-01

Changes in the composition of wood organic matter in dead-standing spruce and larch trees depending on the period after their death have been studied in the north of Central Siberia. The period after tree death has been estimated by means of cross-dating. The results show that changes in the composition of wood organic matter in 63% of cases are contingent on tree species. Wood decomposition in dead-standing trees is accompanied by an increase in the contents of alkali-soluble organic compounds. Lignin oxidation in larch begins approximately 80 years after tree death, whereas its transformation in spruce begins not earlier than after 100 years. In the forest-tundra of Central Siberia, the rate of wood organic matter transformation in dead-standing trees is one to two orders of magnitude lower than in fallen wood, which accounts for their role as a long-term store of carbon and mineral elements in these ecosystems.

Sarcocystis neurona retinochoroiditis in a sea otter (Enhydra lutris kenyoni)

USDA-ARS?s Scientific Manuscript database

Sarcocystis neurona is an important cause of fatal disease in sea otters in the USA. Encephalitis is the predominant lesion and parasites are confined to the central nervous system and muscles. Here we report retinochoroiditis in a sea otter (Enhydra lutris kenyoni) found dead on Copalis Beach, WA, ...

50 CFR 648.143 - Minimum sizes.

Code of Federal Regulations, 2011 CFR

2011-10-01

... black sea bass fishery adopted by the ASMFC. (1) Commercial ACL overage evaluation. The commercial sector ACL will be evaluated based on a single-year examination of total catch (landings and dead discards). Both landings and dead discards will be evaluated in determining if the commercial sector ACL...

Simulation of Simple Controlled Processes with Dead-Time.

ERIC Educational Resources Information Center

Watson, Keith R.; And Others

1985-01-01

The determination of closed-loop response of processes containing dead-time is typically not covered in undergraduate process control, possibly because the solution by Laplace transforms requires the use of Pade approximation for dead-time, which makes the procedure lengthy and tedious. A computer-aided method is described which simplifies the…

Rates and cycles of microbial sulfate reduction in the hyper-saline Dead Sea over the last 200 kyrs from sedimentary d34S and d18O(SO4)

NASA Astrophysics Data System (ADS)

Torfstein, Adi; Turchyn, Alexandra V.

2017-08-01

We report the d34S and d18O(SO4) values measured in gypsum, pyrite, and elemental sulfur through a 456-m thick sediment core from the center of the Dead Sea, representing the last 200 kyrs, as well as from the exposed glacial outcrops of the Masada M1 section located on the margins of the modern Dead Sea. The results are used to explore and quantify the evolution of sulfur microbial metabolism in the Dead Sea and to reconstruct the lake’s water column configuration during the late Quaternary. Layers and laminae of primary gypsum, the main sulfur-bearing mineral in the sedimentary column, display the highest d34S and d18O(SO4) in the range of 13-28‰ and 13-30‰, respectively. Within this group, gypsum layers deposited during interglacials have lower d34S and d18O(SO4) relative to those associated with glacial or deglacial stages. The reduced sulfur phases, including chromium reducible sulfur, and secondary gypsum crystals are characterized by extremely low d34S in the range of -27 to +7‰. The d18O(SO4) of the secondary gypsum in the M1 outcrop ranges from 8 to 14‰. The relationship between d34S and d18O(SO4) of primary gypsum suggests that the rate of microbial sulfate reduction was lower during glacial relative to interglacial times. This suggests that the freshening of the lake during glacial wet intervals, and the subsequent rise in sulfate concentrations, slowed the rate of microbial metabolism. Alternatively, this could imply that sulfate-driven anaerobic methane oxidation, the dominant sulfur microbial metabolism today, is a feature of the hypersalinity in the modern Dead Sea. Sedimentary sulfides are quantitatively oxidized during epigenetic exposure, retaining the lower d34S signature; the d18O(SO4) of this secondary gypsum is controlled by oxygen atoms derived equally from atmospheric oxygen and from water, which is likely a unique feature in this hyperarid environment.

Understanding Flash Flood Generation in the Arid Region of the Dead Sea

NASA Astrophysics Data System (ADS)

Merz, R.; Hennig, H.; Rödiger, T.; Laronne, J. B.

2017-12-01

The arid region of the Dead Sea is prone by flash floods. Such flash floods in (semi-) arid regions are impressive. Generated within minutes, the peak unit discharge can be as high as 25 m³/s km². Floods are the main mechanism supplying water to alluvial aquifers, forming fluvial landscapes including canyons and often causing damage to humans, infrastructure, industry and tourism. Existing hydrological models in this region focus on peak discharges. However, these models are often based on simplified concepts and/or on concepts which were developed for humid regions. To more closely relate such models to local conditions, processes within catchments where floods occur require consideration. Therefore, a measurement network of rain gauges and level loggers to monitor runoff was installed in the beginning of the 2015/16 hydrological season in the tributaries of Wadi Arugot. The Arugot catchment is one of the largest ephemeral Wadis draining to the western shoreline of the Dead Sea at 450 m bsl. Due to the high gradient in elevation, the climate within the basin ranges from semiarid in the Judean Mountains, to hyper-arid near the Dead Sea with respective mean annual rainfall of 650 and 50 mm. The installed rain gauge network in the mountains is more dense compared to the Dead Sea area. Arid to semiarid catchments have different runoff generation processes compared to humid regions due local storm rainfall, low density of vegetation cover as well as patchy and shallow soil. These characteristics limit the contribution of groundwater flow, saturated overland flow and shallow subsurface flow, and therefore Hortonian overland flow is the most important contributor to overland flow. First analyses of the runoff data have shown that the storage capacity in the mountain area is lower compared to the more arid region. This is an evidence of high transmission losses in the coarse gravel wadi bed, therefore having a high permeability. The rain event duration and the amount of rain could not be determined as the only factors which lead to the generation of runoff events.

Geochemical characterization of fluids along the Dead Sea Rift: implications for fluids sources and regional geodynamic setting

NASA Astrophysics Data System (ADS)

Inguaggiato, Claudio; Censi, Paolo; D'Alessandro, Walter; Zuddas, Pierpaolo

2016-04-01

The Dead Sea Fault where a lateral displacement between the African and Arabian plates occurs is characterized by anomalous heat flux in the northern Israel area close to the border with Syria and Jordan (Shalev et al., 2012). The concentrations of He and CO2, and isotopic composition of He and total dissolved inorganic carbon were studied in cold and thermal waters collected along the Dead Sea Fault, in order to investigate the source of volatiles and their relationship with the tectonic framework of the Dead Sea Fault. The waters with higher temperature (up to 57.2 ° C) are characterized by higher amounts of CO2and helium (up to 55.72 and 1.91*10-2 cc l-1, respectively). Helium isotopic data (R/Ra from 0.11 to 2.14) and 4He/20Ne ratios (0.41 - 106.86) show the presence of deep-deriving fluids consisting of a variable mixture of mantle and crust end-members, with the former reaching up to 35%. Carbon isotope signature of total dissolved carbon from hot waters falls within the range of magmatic values, suggesting the delivery of deep-seated CO2. The geographical distribution of helium isotopic data and isotopic carbon (CO2) values coupled with (CO2/3He ratios) indicate a larger contribution of mantle-derived fluids affecting the northern part of the investigated area, where the waters reach the highest temperature and anomalous heat flux was recognized by Shalev et al. (2012). Such occurrence is probably favoured by the peculiar tectonic framework recognized in the northern part of Israel (Segev et al., 2006), including a Moho discontinuity up-rise and/or the presence of a deep fault system coupled with the recent magmatic activity. References: Segev, A., Rybakov, M., Lyakhovsky, V, Hofstetter, A, Tibor, G., Goldshmidt, V., 2006. The structure, isostasy and gravity field of the Levant continental margin and the southeast Mediterranean area. Tectonophysics 425, 137-157. Shalev, E., Lyakhosky, V., Weinstein, Y., Ben-Avraham, Z., 2013. The thermal structure of Israel and Dead Sea Fault. Tectonophysics 602, 69-77.

Self-accelerated development of salt karst during flash floods along the Dead Sea Coast, Israel

NASA Astrophysics Data System (ADS)

Avni, Yoav; Lensky, Nadav; Dente, Elad; Shviro, Maayan; Arav, Reuma; Gavrieli, Ittai; Yechieli, Yoseph; Abelson, Meir; Lutzky, Hallel; Filin, Sagi; Haviv, Itai; Baer, Gidon

2016-01-01

We document and analyze the rapid development of a real-time karst system within the subsurface salt layers of the Ze'elim Fan, Dead Sea, Israel by a multidisciplinary study that combines interferometric synthetic aperture radar and light detection and ranging measurements, sinkhole mapping, time-lapse camera monitoring, groundwater level measurements and chemical and isotopic analyses of surface runoff and groundwater. The >1 m/yr drop of Dead Sea water level and the subsequent change in the adjacent groundwater system since the 1960s resulted in flushing of the coastal aquifer by fresh groundwater, subsurface salt dissolution, gradual land subsidence and formation of sinkholes. Since 2010 this process accelerated dramatically as flash floods at the Ze'elim Fan were drained by newly formed sinkholes. During and immediately after these flood events the dissolution rates of the subsurface salt layer increased dramatically, the overlying ground surface subsided, a large number of sinkholes developed over short time periods (hours to days), and salt-saturated water resurged downstream. Groundwater flow velocities increased by more than 2 orders of magnitudes compared to previously measured velocities along the Dead Sea. The process is self-accelerating as salt dissolution enhances subsidence and sinkhole formation, which in turn increase the ponding areas of flood water and generate additional draining conduits to the subsurface. The rapid terrain response is predominantly due to the highly soluble salt. It is enhanced by the shallow depth of the salt layer, the low competence of the newly exposed unconsolidated overburden and the moderate topographic gradients of the Ze'elim Fan.

GPS measurements of crustal deformation across the southern Arava Valley section of the Dead Sea Fault and implications to regional seismic hazard assessment

NASA Astrophysics Data System (ADS)

Hamiel, Yariv; Masson, Frederic; Piatibratova, Oksana; Mizrahi, Yaakov

2018-01-01

Detailed analysis of crustal deformation along the southern Arava Valley section of the Dead Sea Fault is presented. Using dense GPS measurements we obtain the velocities of new near- and far-field campaign stations across the fault. We find that this section is locked with a locking depth of 19.9 ± 7.7 km and a slip rate of 5.0 ± 0.8 mm/yr. The geodetically determined locking depth is found to be highly consistent with the thickness of the seismogenic zone in this region. Analysis of instrumental seismic record suggests that only 1% of the total seismic moment accumulated since the last large event occurred about 800 years ago, was released by small to moderate earthquakes. Historical and paleo-seismic catalogs of this region together with instrumental seismic data and calculations of Coulomb stress changes induced by the 1995 Mw 7.2 Nuweiba earthquake suggest that the southern Arava Valley section of the Dead Sea Fault is in the late stage of the current interseismic period.

Communicating mega-projects in the face of uncertainties: Israeli mass media treatment of the Dead Sea Water Canal.

PubMed

Fischhendler, Itay; Cohen-Blankshtain, Galit; Shuali, Yoav; Boykoff, Max

2015-10-01

Given the potential for uncertainties to influence mega-projects, this study examines how mega-projects are deliberated in the public arena. The paper traces the strategies used to promote the Dead Sea Water Canal. Findings show that the Dead Sea mega-project was encumbered by ample uncertainties. Treatment of uncertainties in early coverage was dominated by economics and raised primarily by politicians, while more contemporary media discourses have been dominated by ecological uncertainties voiced by environmental non-governmental organizations. This change in uncertainty type is explained by the changing nature of the project and by shifts in societal values over time. The study also reveals that 'uncertainty reduction' and to a lesser degree, 'project cancellation', are still the strategies most often used to address uncertainties. Statistical analysis indicates that although uncertainties and strategies are significantly correlated, there may be other intervening variables that affect this correlation. This research also therefore contributes to wider and ongoing considerations of uncertainty in the public arena through various media representational practices. © The Author(s) 2013.

A Unified Approach to Adaptive Neural Control for Nonlinear Discrete-Time Systems With Nonlinear Dead-Zone Input.

PubMed

Liu, Yan-Jun; Gao, Ying; Tong, Shaocheng; Chen, C L Philip

2016-01-01

In this paper, an effective adaptive control approach is constructed to stabilize a class of nonlinear discrete-time systems, which contain unknown functions, unknown dead-zone input, and unknown control direction. Different from linear dead zone, the dead zone, in this paper, is a kind of nonlinear dead zone. To overcome the noncausal problem, which leads to the control scheme infeasible, the systems can be transformed into a m -step-ahead predictor. Due to nonlinear dead-zone appearance, the transformed predictor still contains the nonaffine function. In addition, it is assumed that the gain function of dead-zone input and the control direction are unknown. These conditions bring about the difficulties and the complicacy in the controller design. Thus, the implicit function theorem is applied to deal with nonaffine dead-zone appearance, the problem caused by the unknown control direction can be resolved through applying the discrete Nussbaum gain, and the neural networks are used to approximate the unknown function. Based on the Lyapunov theory, all the signals of the resulting closed-loop system are proved to be semiglobal uniformly ultimately bounded. Moreover, the tracking error is proved to be regulated to a small neighborhood around zero. The feasibility of the proposed approach is demonstrated by a simulation example.

Columbia's payload bay with Earth in the background

NASA Image and Video Library

2009-06-24

STS003-17-806 (22-30 March 1982) --- A 70mm out-the-window view showing Israel, the Dead Sea, Sea of Galilee, Jordan River, Sinai, Jordan, the Red Sea and Egypt (in background). Rested Remote Manipulator System (RMS) arm and part of the aft section of space shuttle Columbia in foreground. Photo credit: NASA

50 CFR 300.223 - Purse seine fishing restrictions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... thereof be kept on board and delivered to NMFS for research purposes. (vii) Sea turtle release. After... retention of a dead sea turtle for research. In releasing a sea turtle the vessel owner or operator must: (A) Place the vessel engine in neutral gear so that the propeller is disengaged and the vessel is stopped...

Monitoring of sinkholes and subsidence affecting the Jordanian coast of the Dead Sea through Synthetic Aperture Radar data and last generation Sentinel-1 data

NASA Astrophysics Data System (ADS)

Tessari, Giulia; Riccardi, Paolo; Lecci, Daniele; Pasquali, Paolo; Floris, Mario

2017-04-01

Since the mid-1980s the coast of the Dead Sea is affected by sinkholes occurring over and around the emerged mud and salt flats. Strong subsidence and landslides also affect some segments of the coast. Nowadays, several thousands of sinkholes attest that the degradation of the Dead Sea coast is worsening. Furthermore, soil deformations are interesting the main streets running along both the Israeli and Jordanian sides of the Dead Sea. These hazards are due to the dramatic dropping of the Dead Sea level, characterized by an increasing rate from about 60 cm/yr in the 1970s up to 1 m/yr in the 2000s, which provokes a lowering of the fresh-saline groundwater interface, replacing the hypersaline groundwater with fresh water and causing a consequent erosion of the subsurface salt layers. Subsidence, sinkholes, river erosion and landslides damage bridges, roads, dikes, houses, factories worsening this ongoing disaster. One of the most emblematic effects is the catastrophic collapse of a 12-km newly constructed dyke, located on the Lisan Peninsula (Jordan), occurred in 2000. Differential Interferometric Synthetic Aperture Radar (DInSAR) techniques and Advanced stacking DInSAR techniques (A-DInSAR) were applied to investigate sinkholes and subsidence affecting the Jordanian coast of the Dead Sea. The use of SAR data already proof to be efficient on the risk management of the area, allowing to identify a vulnerable portion of an Israeli highway, averting a possible collapse. Deformation analysis has been focused on the Ghor Al Haditha area and Lisan peninsula, located in the South-Eastern part of the lake coast. The availability of a huge database of SAR data, since the beginning of the 90s, allowed to observe the evolution of the displacements which are damaging this area. Furthermore, last generation Sentinel-1 data, acquired by the ESA mission, were processed to obtain information about the recent evolution of the subsidence and sinkholes affecting the study area, from the end of 2014 to the present. Important subsidence can be noticed mainly in correspondence of the emerging coast. Moreover, some solar evaporation pools used for salt production are injured by high deformations. Analysis of results obtained from SAR satellite data allows to identify different hazard processing affecting the study area and define the displacement time-series to clearly describe the evolution of the different phenomena, resulting as an effective tool to prevent damage and collapses. Furthermore, vulnerability maps can be created and possible precursor behaviour can be highlighted demonstrating the predictive capability of these data.

Late Quaternary environmental and human events at En Gedi, reflected by the geology and archaeology of the Moringa Cave (Dead Sea area, Israel)

NASA Astrophysics Data System (ADS)

Lisker, Sorin; Porat, Roi; Davidovich, Uri; Eshel, Hanan; Lauritzen, Stein-Erik; Frumkin, Amos

2007-09-01

The Moringa Cave within Pleistocene sediments in the En Gedi area of the Dead Sea Fault Escarpment contains a sequence of various Pleistocene lacustrine deposits associated with higher-than-today lake levels at the Dead Sea basin. In addition it contains Chalcolithic remains and 5th century BC burials attributed to the Persian period, cemented and covered by Late Holocene travertine flowstone. These deposits represent a chain of Late Pleistocene and Holocene interconnected environmental and human events, echoing broader scale regional and global climate events. A major shift between depositional environments is associated with the rapid fall of Lake Lisan level during the latest Pleistocene. This exposed the sediments, providing for cave formation processes sometime between the latest Pleistocene (ca. 15 ka) and the Middle Holocene (ca. 4500 BC), eventually leading to human use of the cave. The Chalcolithic use of the cave can be related to a relatively moist desert environment, probably related to a shift in the location of the northern boundary of the Saharo-Arabian desert belt. The travertine layer was U-Th dated 2.46 ± 0.10 to 2.10 ± 0.04 ka, in agreement with the archaeological finds from the Persian period. Together with the inner consistency of the dating results, this strongly supports the reliability of the radiometric ages. The 2.46-2.10 ka travertine deposition within the presently dry cave suggests a higher recharge of the Judean Desert aquifer, correlative to a rising Dead Sea towards the end of the 1st millennium BC. This suggests a relatively moist local and regional climate facilitating human habitation of the desert.

New types of submarine groundwater discharge from a saliferous clay formation - the case of the Dead Sea

NASA Astrophysics Data System (ADS)

Siebert, Christian; Broder, Merkel; Thomas, Pohl; Yossi, Yechieli; Eldat, Hazan; Danny, Ionescu; Ulf, Mallast

2017-04-01

Along the coastline of the hyper-saline and dramatically dropping Dead Sea, fresh to highly saline groundwaters discharge abundantly from dry falling lakebed. During its history, the level and hence salinity of the lake strongly fluctuated, resulting in the deposition of an alternating sequence of clayey and chemical sediments (mainly halite, carbonates and sulfates), intercalated by thick beds of halite and of coarse clastics around wadi outlets, respectively. Due to the asymmetrical shape of the lake's basin, these strata are deposited unequally along the eastern and western flank, why only groundwaters coming from the west have to pass thick layers of these sediments on their way into the lake. On the base of trace elements (REE), element ratios, stable and radioisotopes and microbiological findings, the observed onshore and offshore springs revealed, freshwaters discharge from both Cretaceous limestone aquifers and efficiently dissolve the easily soluble halite and flush the interstitial brines from the saliferous clay formation, immediately after entering the sedimentary strata. Abundant microbial activity result in the widespread production of sulfuric acid, accelerating erosion of carbonates and sulfates. These processes result in a fast and striking karstification of the strata, enabling groundwaters to transcendent the fresh/saltwater interface trough open pipes. As results, submarine groundwater discharge (SGD) occurs randomly and in addition to terrestrial, submarine sinkholes develop very quickly too. Due to the variable maturity of the flow paths, salinity and chemical composition of SGD shows an extremely wide range, from potable water to TDS of >250 g/l. Submarine emerging groundwaters with salinities even higher then that of the Dead Sea and distinctly different chemical and isotopic composition form outlets, which are not known elsewhere and represent a novel and unique type of SGD, only observed in the Dead Sea yet.

Crustal and upper mantle structure of the north-east of Egypt and the Afro-Arabian plate boundary region from Rayleigh-wave analysis

NASA Astrophysics Data System (ADS)

Corchete, V.; Chourak, M.; Hussein, H. M.; Atiya, K.; Timoulali, Y.

2017-05-01

The crustal and mantle structure of the north-eastern part of Egypt and the surrounding area is shown by means of S-velocity maps for depths ranging from zero to 45 km, determined by the regionalization and inversion of Rayleigh-wave dispersion. This analysis shows several types of crust with an average S-velocity ranging from 2.5 to 3.9 km/s. The values of S-velocity range from 2.5 km/s at the surface to 3.4 km/s at 10 km depth for the Sinai Peninsula, Gulf of Aqaba, Gulf of Suez, Red Sea, Dead Sea, western part of Dead sea and Arabian Plate. In the lower crust, the values of the S-velocity reach 4.0 km/s. In the uppermost mantle, the S-velocities range from 4.4 to 4.7 km/s. The crustal thickness ranges from the oceanic thin crust (around 15-20 km of thickness), for Red Sea and the extended continental margins, to 35-45 km of thickness for the Arabian plate. A gradual increasing crustal thickness is observed from north-east to south-west. While the Moho is located at 30-35 km of depth under the Sinai Peninsula, Gulf of Aqaba, Dead Sea Fault (DSF) and Dead Sea, a thinner crust (20-25 km of thickness) is found at the east of DSF and under the northern and the southern part of the Gulf of Suez. The crustal thickness varies within Sinai from the southern edge to the north, which provided an evidence for the presence of an Early Mesozoic passive margin with thinned continental crust in the north of Sinai. The change of crustal structure between the Gulf of Aqaba and the Gulf of Suez is due to the different tectonic and geodynamic processes affecting Sinai. In general, our results are consistent with surface geology and the Moho depth inferred from reflection and refraction data, receiver function, surface-wave analysis and P-S tomography. The strong variations in the base of the Moho reflect the complex evolution of the African and Arabian plate boundary region.

Thermal impacts of magmatic intrusions on dolomitization processes in the Tiberias Basin, Jordan-Dead Sea Transform

NASA Astrophysics Data System (ADS)

Koltzer, Nora; Möller, Peter; Inbar, Nimrod; Siebert, Christian; Rosenthal, Eliyahu; Al-Raggad, Marwan; Magri, Fabien

2017-04-01

The Tiberias Basin (TB) is located within the Jordan-Dead Sea Transform and is bordered to the west by the Lower Galilee (Israel), where Pliocene basalts cover an area of 35 km2. Hydrochemical analyses highlight that two types of brines exist around Lake Tiberias (LT) (Mandel 1965; Möller et al. 2009): (1) Along the eastern side of LT, brine is characterized by Mg/Ca>1, which resulted from evaporation of seawater during the Late Miocene, whereas (2) along the western side of the lake, brine is characterized by Mg/Ca<1, possibly formed out of the Mg-rich brine by dolomitization of limestones (Möller et al. 2012). Dolomitization of limestones occurs at temperatures of at least 100 °C. We suppose that basalts which erupted through numerous fissures, forming nowadays sills within the Cretaceous and Eocene limestones, sufficiently heated the formations, which build up the Lower Galilee, west of LT. As a result, the Cenomanian Formations, where the original brine is mostly buried, were only sufficiently heated in the eastern Galilee. In this study, we try to estimate to which extent and through which mechanisms fissure eruptions have induced heated brine to flow within the limestone aquifers. 2D simulations of coupled heat transport and fluid flow show that different aspects control the heat transport in the limestone aquifer. Preliminary results indicate that conductive heat transport generates sharp temperature fronts that extent 30 meters after 5 years of continuous magmatic intrusion from the fissures, ruling out heat conduction as a major mechanism for dolomitization. By contrast, convective cells in the Turonian and Cenomanian aquiferous formations have the potential to develop at different scales that depend on (a) hydraulic conductivity and porosity of the aquifer, (b) the orientation of the regional flow and (c) the topography of the aquifer. As a result of convective flow, brines surrounding a single fissure intrusion are heated more than 100 °C up to a width of 2 km in both directions. The thermally induced flow velocities are in the range of 2 m/year. In simulations with multiple intrusions, the thermal plume can stretch over 5.5 km. The simulations indicate that magmatic induced advective/convective heating may have generated temperature conditions favorable for dolomitization, which in turn may explain the existence of two different brines that are found around the LT. References Mandel S. (1965). Hydrogeological Investigations of the areas surrounding Lake Tiberias. Water Planning for Israel. Volumes 1-2 210 p. Möller P., Siebert C., Geyer S., Inbar N., Rosenthal E., Flexer A., Zilberbrand M. (2012). Relationship of brines in the Kinnarot Basin, Jordan-Dead Sea Rift Valley. Geofluids, 12(2), 166-181. Möller P., Rosenthal E., Geyer S. (2009). Characterization of aquifer environments by major and minor elements and stable isotopes of sulfate In: Hoetzel H., Möller P., Rosenthal E. (Eds) Water of the Jordan Balley. Pp. 83-122.

Variability of lipid constituents of the coil cyanobacterium Microcoleus vaginatus from the Dead Sea basin and Negev desert.

PubMed

Dembitsky, V M; Dor, I; Shkrob, I

2000-12-01

A study of lipids of the soil cyanobacterium Microcoleus vaginatus, which was isolated from microbial crusts collected in the Dead Sea basin and in the Negev desert, was performed. Twenty-six hydrocarbons and fatty acids were separated and identified by GC/MS using serially coupled capillary columns of different polarity. Changes in the lipid composition were evaluated by comparison of samples collected from different locations. Heptadecane, 1-heptadecene, 6- and 7-methylheptadecane, hexadecanoic and 9(Z)-octadecenoic acids were identified as the major constituents. Biochemical mechanisms of production of the different lipid compounds under UV irradiation are proposed.

Geology and hydrocarbon potential of the Dead Sea Rift Basins of Israel and Jordan

USGS Publications Warehouse

Coleman, James; ten Brink, Uri S.

2016-01-01

Geochemical analyses indicate that the source of all oils, asphalts, and tars recovered in the Lake Lisan basin is the Ghareb Formation. Geothermal gradients along the Dead Sea fault zone vary from basin to basin. Syn-wrench potential reservoir rocks are highly porous and permeable, whereas pre-wrench strata commonly exhibit lower porosity and permeability. Biogenic gas has been produced from Pleistocene reservoirs. Potential sealing intervals may be present in Neogene evaporites and tight lacustrine limestones and shales. Simple structural traps are not evident; however, subsalt traps may exist. Unconventional source rock reservoir potential has not been tested.

The measurement and analysis of normal incidence solar UVB radiation and its application to the photoclimatherapy protocol for psoriasis at the Dead Sea, Israel.

PubMed

Kudish, Avraham I; Harari, Marco; Evseev, Efim G

2011-01-01

The broad-band normal incidence UVB beam radiation has been measured at Neve Zohar, Dead Sea basin, using a prototype tracking instrument composed of a Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The diffuse and beam fraction of the solar global UVB radiation have been determined using the concurrently measured solar global UVB radiation. The diffuse fraction was observed to exceed 80% throughout the year. The application of the results of these measurements to the possible revision of the photoclimatherapy protocol for psoriasis patients at the Dead Sea medical spas is now under investigation. The suggested revision would enable the sun-exposure treatment protocol to take advantage of the very high diffuse fraction by allowing the patient to receive the daily dose of UVB radiation without direct exposure to the sun, viz. receive the diffuse UVB radiation under a sunshade. This would require an increase in sun-exposure time intervals, as the UVB radiation intensity beneath a sunshade is less than that on an exposed surface. © 2010 The Authors. Photochemistry and Photobiology © 2010 The American Society of Photobiology.

Microbiological and parasitological investigation among food handlers in hotels in the Dead Sea area, Jordan.

PubMed

Abdel-Dayem, Muna; Al Zou'bi, Renad; Hani, Rehan Bani; Amr, Zuhair Sami

2014-10-01

Intestinal parasitic and bacterial infections constitute a major health issue in developing countries. The present study investigates and assesses infection rates among food handlers with intestinal parasites and microbial agents in luxurious hotels in the Dead Sea area of Jordan. A total of 901 stool samples were collected from food handlers (35 females and 866 males) employed in four main hotels in the Dead Sea area. Fecal samples were examined microscopically for intestinal parasites. Standard culture and biochemical techniques were used for the isolation and identification of Salmonella and Shigella spp. in stool samples. Five species of protozoan (Blastocystis hominis, Giardia intestinalis, Entamoeba coli, Entamoeba histolytica, and Endolimax nana), one helminth (Hymenolepis nana), and one cylindrical worm (Enterobius vermicularis) were recovered with an overall infection rate of 3.7%. G. intestinalis was the most prevalent parasitic infection with infection rate of 2.44%. All samples were negative for both Salmonella and Shigella. Findings highlight the important role of food handlers in the transmission of intestinal parasites to high-class clients accommodated in luxury hotels, and stress the urgent need for regular health and parasitologic examination of food handlers. Copyright © 2013. Published by Elsevier B.V.

Towards the establishment of a general rate law for gypsum nucleation

NASA Astrophysics Data System (ADS)

Reznik, Itay J.; Ganor, Jiwchar; Gruber, Chen; Gavrieli, Ittai

2012-05-01

Gypsum nucleation kinetics from a wide range of chemical compositions (1.45 < Ca2+/SO42- < 115), ionic strengths (I = 2.5-10 m) and saturation state with respect to gypsum (Ωgyp = 1.07-8.4) were examined in batch experiments containing mixtures of Ca2+-rich Dead Sea brine and SO42-rich seawater with or without addition of extra Na2SO4 and CaCl2·2H2O. The induction times attained in the present study were compiled together with literature values from experiments carried out under significantly different conditions (synthetic NaCl solutions; I = 0.09-6.3 m; Ca2+/SO42- = 1; Ωgyp:1.59-7.76). Despite the variability in the experimental solutions, a single rate law based on classic nucleation theory was formulated to describe the induction times from more than 80 experiments: logT=log{1}/{3.17·Cs·exp{-}7.08ln2Ω}+0.072·Cs·exp-{1.426}/{ln2Ω} where Tind is the induction time, Cs is the solubility of gypsum and Ω is the saturation state with respect to gypsum. The rate law provides Tind for gypsum precipitation from aqueous solutions at 25 °C, containing no synthetic antiscalants or catalysts, within a 95% confidence interval within a factor of 5. Based on this rate law, we show that at present most of the precipitation of gypsum from the Dead Sea brine occurs following significant evaporation in the industrial evaporation ponds and not in the Dead Sea itself. Whereas Tind in Dead Sea brines is very long (on the order of 3 years), the evaporation of brine in the industrial ponds leads to increased Ω values, and thus to short Tind in the order of a few days. However, if seawater or reject brine from seawater desalinization will be introduced to the Dead Sea to restore its declining level, Tind will be significantly reduced and gypsum nucleation and precipitation will occur. For evaporated seawater, the proposed rate law predicts that even though saturation is obtained when seawater is evaporated by a factor of 2.8, gypsum will nucleate at reasonable times (few years) only when seawater are evaporated by a factor of ˜3.3.

Relationships between of Sea Urchins Abundance, Macroalgae and Coral Closure on the Cemara Kecil island

NASA Astrophysics Data System (ADS)

Suryanti, Suryanti; Ain, Churun; Latifah, Nurul

2018-05-01

Sea urchins are one of the key species for coral reef communities because have the capability for controlling populations of microalgae. The existence of sea urchins in an waters ecosystem influenced by abiotic and biotic environmental factors such as intraspecific or intraspecific interactions. This study aims to determine the relationship between the abundance of Sea Urchins, Macroalga on massive coral, and coral cover on Cemara Kecil Island by PCA analysis. The study was conducted in May 2017 in Cemara Kecil Island. Method of research with Haphazard sampling technique. The results indicate that numbers of sea urchins found ranges from 78-130 ind/m2, an abundance of macroalgae found are Sargassum sp 1.36%, Caulerpa sp.7.43% and Padina sp 91.21%. The results of substrate cover are living coral 47,21%, dead coral 23.33%, other fauna 2.85% and abiotic element 26,61%. Based on the results of PCA analysis that Sea Urchin abundance has a positive correlation with the closure of Coral Reef and Caulerpa sp. While the Padina sp and Sargassum sp have a positive correlation as well as abiotic factors, dead coral, and other fauna.

Butyltin residues in southern sea otters (Enhydra lutris nereis) found dead along California coastal waters

USGS Publications Warehouse

Kannan, K.; Guruge, K.S.; Thomas, N.J.; Tanabe, S.; Giesy, J.P.

1998-01-01

Tributyltin (TBT) and its degradation products, mono- (MBT) and dibutyltin (DBT), were determined in liver, kidney, and brain tissues of adult southern sea otters (Enhydra lutris nereis) found dead along the coast of California during 1992a??1996. Hepatic concentrations of butyltin compounds (BTs = MBT + DBT + TBT) ranged from 40 to 9200 ng/g wet wt, which varied depending on the sampling location and gender. Concentrations of BTs in sea otters were comparable to those reported in stranded bottlenose dolphins from the U.S. Atlantic Coast during 1989a??1994. Greater accumulation of butyltins in sea otters was explained by their bottom-feeding habit and the diet that consists exclusively of invertebrates such as mollusks and gastropods. Livers of female sea otters contained approximately 2-fold greater concentrations of BTs than did those of males. The composition of butyltin compounds in sea otter tissues was predominated by TBT in most cases and suggestive of recent exposure. Large harbors such as Monterey Harbor that handle ships legally painted with TBT-containing antifouling paints continued to experience ecotoxicologically significant butyltin contamination. Sea otters, which were affected by infectious diseases, contained greater concentrations of BTs in their tissues than those that died from trauma and other unknown causes.

Adaptive NN tracking control of uncertain nonlinear discrete-time systems with nonaffine dead-zone input.

PubMed

Liu, Yan-Jun; Tong, Shaocheng

2015-03-01

In the paper, an adaptive tracking control design is studied for a class of nonlinear discrete-time systems with dead-zone input. The considered systems are of the nonaffine pure-feedback form and the dead-zone input appears nonlinearly in the systems. The contributions of the paper are that: 1) it is for the first time to investigate the control problem for this class of discrete-time systems with dead-zone; 2) there are major difficulties for stabilizing such systems and in order to overcome the difficulties, the systems are transformed into an n-step-ahead predictor but nonaffine function is still existent; and 3) an adaptive compensative term is constructed to compensate for the parameters of the dead-zone. The neural networks are used to approximate the unknown functions in the transformed systems. Based on the Lyapunov theory, it is proven that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded and the tracking error converges to a small neighborhood of zero. Two simulation examples are provided to verify the effectiveness of the control approach in the paper.

Skylab 3, Saturn S-4B stage falls away from the CM after separation

NASA Image and Video Library

2011-12-13

SL3-114-1634 (July-September 1973) --- Skylab 3, Saturn S-4B (S-IVB) stage falls away from the Command Module (CM) after separation. Earth limb in background, pass over Israel, the Dead Sea and the Mediterranean Sea. Photo credit: NASA

Ageing of native cellulose fibres under archaeological conditions: textiles from the Dead Sea region studied using synchrotron X-ray microdiffraction

NASA Astrophysics Data System (ADS)

Müller, M.; Murphy, B.; Burghammer, M.; Riekel, C.; Pantos, E.; Gunneweg, J.

2007-12-01

Archaeological cellulose textile fibres (linen and cotton) from caves in the Dead Sea region were investigated using synchrotron X-ray microdiffraction. The degradation of the up to 2100 year old fibres was found to depend on the climatic conditions at the place of storage. The size and the lattice parameters of the cellulose nanocrystals (microfibrils) in the fibres change upon degradation; these parameters are shown to be strongly correlated, leading to a microscopic description of the degradation process in terms of molecular disorder. Artificial ageing does not seem to reproduce the effects observed here for the first time on archaeological cellulose fibres.

Panoramic Sinai Peninsula, Red Sea

NASA Image and Video Library

1984-10-13

An excellent panoramic view of the entire Sinai Peninsula (29.0N, 34.0E) and the nearby Nile River Delta and eastern Mediterranean coastal region. The Suez Canal, at the top of the scene just to the right of the Delta, connects the Mediterranean Sea with the Gulf of Suez on the west side of the Sinai Peninsula and the Gulf of Aqaba is on the west where they both flow into the Red Sea. At upper right, is the Dead Sea, Jordan River and Lake Tiberius.

Geology of the Arabian Peninsula; shield area of western Saudi Arabia

USGS Publications Warehouse

Brown, Glen F.; Schmidt, Dwight L.; Huffman, A. Curtis

1989-01-01

A second stage of sea-floor spreading about 4-5 m.y. produced the Red Sea axial trough, consisting of oceanic crust, as well as renewed uplift and tilting of the three tectonic provinces in response to compression from counterclockwise rotation against the Dead Sea Rift. This late movement caused widespread major stream capture, especially along the wadis that formerly drained southwesterly or northwesterly, the channels turning westward through narrow gorges to the coastal plain and the Red Sea.

Geochemical characterisation of gases along the dead sea rift: Evidences of mantle-co2 degassing

NASA Astrophysics Data System (ADS)

Inguaggiato, C.; Censi, P.; D'Alessandro, W.; Zuddas, P.

2016-06-01

The Dead Sea Transform (DST) fault system, where a lateral displacement between the African and Arabian plates occurs, is characterised by anomalous heat flux in the Israeli area close to the border with Syria and Jordan. The concentration of He and CO2, and isotopic composition of He and total dissolved inorganic carbon were studied in cold and thermal waters collected along the DST, in order to investigate the source of volatiles and their relationship with the tectonic framework of the DST. The waters with higher temperature (up to 57.2 °C) are characterised by higher amounts of CO2 and helium (up to 55.72 and 1.91 ∗ 10- 2 cc l- 1, respectively). Helium isotopic data (R/Ra from 0.11 to 2.14) and 4He/20Ne ratios (0.41-106.86) show the presence of deep-deriving fluids consisting of a variable mixture of mantle and crust end-members, with the former reaching up to 35%. Carbon isotope signature of total dissolved carbon from hot waters falls within the range of magmatic values, suggesting the delivery of deep-seated CO2. The geographical distribution of helium isotopic data and isotopic carbon (CO2) values coupled with (CO2/3He ratios) indicate a larger contribution of mantle-derived fluids affecting the northern part of the investigated area, where the waters reach the highest temperature. These evidences suggest the occurrence of a favourable tectonic framework, including a Moho discontinuity up-rise and/or the presence of a deep fault system coupled with the recent magmatic activity recognised in the northern part of Israel.

Earthquake damage history in Israel and its close surrounding - evaluation of spatial and temporal patterns

NASA Astrophysics Data System (ADS)

Zohar, Motti; Salamon, Amos; Rubin, Rehav

2017-01-01

Israel was hit by destructive earthquakes many times in the course of history. To properly understand the hazard and support effective preparedness towards future earthquakes, we examined the spatial and temporal distribution of the resulted damage. We described in detail our systematic approach to searching the available literature, collecting the data and screening the authenticity of that information. We used GIS (Geographic Information System) to map and evaluate the distribution of the damage and to search for recurring patterns. Overall, it is found that 186 localities were hit, 54 of them at least twice. We also found that Israel was affected by 4, 17, 8 and 2 damaging earthquakes that originated, respectively, from the southern, central, central-northern and northern parts of the Dead Sea Transform (DST). The temporal appearance of the northern earthquakes is clustered; the central earthquakes are more regular in time, whereas no damage from the north-central and the central quakes, with the exception of the year 363 earthquake, seems to have occurred south of the Dead Sea region. Analyzing the distribution of the damage, we realized that the number of the damage reports reflects only half of the incidents that actually happened, attesting to incompleteness of the historical catalogue. Jerusalem is the most reported city with 14 entries, followed by Akko (Acre), Tiberias, Nablus and Tyre with 8, 7, 7 and 6 reports, respectively. In general, localities in the Galilee and north of it suffered more severely than localities in central Israel with the exception of Nablus and the localities along the coastal plain of Israel, most probably due to local site effects. For the sake of hazard management, these observations should be considered for future planning and risk mitigation.

Thyroid hormones in chronic heat exposed men

NASA Astrophysics Data System (ADS)

Gertner, A.; Israeli, R.; Lev, A.; Cassuto, Y.

1983-03-01

Previous reports have indicated that thyroid gland activity, is depressed in the heat. Total thyroxine (T4) and triiodothyronine (T3) serum levels in 17 workers of the metal work shop at a plant near the Dead Sea and 8 workers in Beer Sheva, Israel were examined. The metal workshop of the plant near the Dead Sea is part of a large chemical plant. The one in Beer Sheva is part of a large construction company. Maintenance work, as well as metal work projects are performed in both workshops. During the work shifts, the workers of the Dead Sea plant were exposed to temperatures ranging from 30 36°C (May Oct.) and 14 21°C (Dec. Feb). In Beer Sheva the range was 25 32°C (June Sept.) and 10 17°C (Dec. Feb.). Total T4 was measured by competitive protein binding and total T3 by radioimmunoassay in blood drawn before work (0700) in July and January. In summer. T4 was higher and T3 was lower for both groups than in winter. The observed summer T3 decrease may result from depressed extrathyroidal conversion of T4 to T3. We conclude that the regulation of energy metabolism in hot climates may be related to extrathyroidal conversion of T4 to T3.

Impact of earthquakes on agriculture during the Roman-Byzantine period from pollen records of the Dead Sea laminated sediment

NASA Astrophysics Data System (ADS)

Leroy, Suzanne A. G.; Marco, Shmuel; Bookman, Revital; Miller, Charlotte S.

2010-03-01

The Dead Sea region holds the archives of a complex relationship between an ever-changing nature and ancient civilisations. Regional pollen diagrams show a Roman-Byzantine period standing out in the recent millennia by its wetter climate that allowed intensive arboriculture. During that period, the Dead Sea formed laminites that display mostly a seasonal character. A multidisciplinary study focused on two earthquakes, 31 BC and AD 363, recorded as seismites in the Ze'elim gully A unit III which has been well dated by radiocarbon in a previous study. The sampling of the sediment was done at an annual resolution starting from a few years before and finishing a decade after each earthquake. A clear drop in agricultural indicators (especially Olea and cereals) is shown. These pollen indicators mostly reflect human activities in the Judean Hills and coastal oases. Agriculture was disturbed in large part of the rift valley where earthquake damage affected irrigation and access to the fields. It took 4 to 5 yr to resume agriculture to previous conditions. Earthquakes must be seen as contributors to factors damaging societies. If combined with other factors such as climatic aridification, disease epidemics and political upheaval, they may lead to civilisation collapse.

Re-evaluating the Glacial Vegetation of the Southern Levant and Early Signs of Human Impact on the Environment

NASA Astrophysics Data System (ADS)

Miebach, A.; Chen, C.; Litt, T.

2017-12-01

Assessing paleoenvironmental conditions is crucial to understand the history of modern humans. The southern Levant functioned as a corridor for human migration processes such as the colonization of Europe and the spread of agriculture. Despite its important role in human history, the Levantine paleoenvironment is still insufficiently investigated. In particular, current reconstructions of the paleovegetation are grounded on poor data bases. Here, we revise former hypotheses about the paleovegetation of the southern Levant during the last glacial based on new palynological results from the Sea of Galilee and the Dead Sea. We further evaluate early signs of anthropogenic influences in the Dead Sea catchment by combining evidence of pollen, micro-charcoal, and spores. The palynological results suggest that drought-adapted herbs, dwarf shrubs, and grasses prevailed in the southern Levant during the last glacial. In contrast to the Holocene, there was no belt of continuous and dense Mediterranean vegetation surrounding the Sea of Galilee during MIS 2. Mediterranean elements such as deciduous oaks only occurred in limited amounts and were probably patchily distributed in the whole study area. The vegetation and moisture gradient was not as strong as today. Since the Lateglacial, the Dead Sea region witnessed several rapid environmental changes. Phases with considerably reduced woodland density, increased fire activity, and enhanced catchment erosion occurred. Although climatic triggers were possible, there is a strong indication of anthropogenic influences due to overall increasing human activities in the region. The study gains new insights into environmental responses of the southern Levant to climate variations in the past. It also contributes towards our understanding of human-environmental interactions during the early Holocene.

Annual dynamics of halite precipitation in the Dead Sea: In situ observations and their geological implications

NASA Astrophysics Data System (ADS)

Sirota, Ido; enzel, Yehouda; Lensky, Nadav G.

2017-04-01

Layered halite sequences deposited in deep basins throughout the geological record. However, analogues of such sequences are commonly studied in sallow environments. Here we study active precipitation of halite layers from the only modern analog for deep, halite-precipitating basin, the hypersaline Dead Sea. In situ observations in the Dead Sea link seasonal thermohaline stratification, halite saturation, and the characteristics of the actively forming halite layers. The spatiotemporal evolution of halite precipitation in the Dead Sea was characterized by means of monthly observations of the i) lake thermohaline stratification (temperature, salinity, and density), ii) degree of halite saturation, and iii) textural evolution of the active halite deposits. We present the observed relationships between textural characteristics of layered halite deposits (i.e. grain size, consolidation, and roughness) and the degree of saturation, which in turn reflected the limnology and hydro-climatology. The lakefloor is divided into two principle environments: A deep, hypolimnetic and a shallow, epilimnetic lakefloor. In the deeper hypolimnetic lakefloor halite continuously precipitates with seasonal variations: (a) during summer, consolidated coarse halite crystals form rough surfaces under slight super-saturation. (b) During winter, unconsolidated, fine halite crystals form smooth seafloor deposits under high supersaturation. The observations also emphasize the thought regarding seasonal alternation of halite crystallization mechanism. The shallow epilimnetic lake floor is highly influenced by the seasonal temperature variations, and by intensive summer dissolution of part of the previous year's halite deposit which results in thin sequences with annual unconformities. This emphasizes the control of temperature seasonality on the precipitated halite layers characteristics. In addition, precipitation of halite in the hypolimnetic floor, on the expense of the dissolution of the epilimnetic floor, results in lateral focusing and thickening of halite deposit in the deeper part of the basin and thinning of the deposits in shallow marginal basins.

Changing flood frequencies under opposing late Pleistocene eastern Mediterranean climates.

PubMed

Ben Dor, Yoav; Armon, Moshe; Ahlborn, Marieke; Morin, Efrat; Erel, Yigal; Brauer, Achim; Schwab, Markus Julius; Tjallingii, Rik; Enzel, Yehouda

2018-05-31

Floods comprise a dominant hydroclimatic phenomenon in aridlands with significant implications for humans, infrastructure, and landscape evolution worldwide. The study of short-term hydroclimatic variability, such as floods, and its forecasting for episodes of changing climate therefore poses a dominant challenge for the scientific community, and predominantly relies on modeling. Testing the capabilities of climate models to properly describe past and forecast future short-term hydroclimatic phenomena such as floods requires verification against suitable geological archives. However, determining flood frequency during changing climate is rarely achieved, because modern and paleoflood records, especially in arid regions, are often too short or discontinuous. Thus, coeval independent climate reconstructions and paleoflood records are required to further understand the impact of climate change on flood generation. Dead Sea lake levels reflect the mean centennial-millennial hydrological budget in the eastern Mediterranean. In contrast, floods in the large watersheds draining directly into the Dead Sea, are linked to short-term synoptic circulation patterns reflecting hydroclimatic variability. These two very different records are combined in this study to resolve flood frequency during opposing mean climates. Two 700-year-long, seasonally-resolved flood time series constructed from late Pleistocene Dead Sea varved sediments, coeval with significant Dead Sea lake level variations are reported. These series demonstrate that episodes of rising lake levels are characterized by higher frequency of floods, shorter intervals between years of multiple floods, and asignificantly larger number of years that experienced multiple floods. In addition, floods cluster into intervals of intense flooding, characterized by 75% and 20% increased frequency above their respective background frequencies during rising and falling lake-levels, respectively. Mean centennial precipitation in the eastern Mediterranean is therefore coupled with drastic changes in flood frequencies. These drastic changes in flood frequencies are linked to changes in the track, depth, and frequency of mid-latitude eastern Mediterranean cyclones, determining mean climatology resulting in wetter and drier regional climatic episodes.

Ecological extinction and evolution in the brave new ocean

PubMed Central

Jackson, Jeremy B. C.

2008-01-01

The great mass extinctions of the fossil record were a major creative force that provided entirely new kinds of opportunities for the subsequent explosive evolution and diversification of surviving clades. Today, the synergistic effects of human impacts are laying the groundwork for a comparably great Anthropocene mass extinction in the oceans with unknown ecological and evolutionary consequences. Synergistic effects of habitat destruction, overfishing, introduced species, warming, acidification, toxins, and massive runoff of nutrients are transforming once complex ecosystems like coral reefs and kelp forests into monotonous level bottoms, transforming clear and productive coastal seas into anoxic dead zones, and transforming complex food webs topped by big animals into simplified, microbially dominated ecosystems with boom and bust cycles of toxic dinoflagellate blooms, jellyfish, and disease. Rates of change are increasingly fast and nonlinear with sudden phase shifts to novel alternative community states. We can only guess at the kinds of organisms that will benefit from this mayhem that is radically altering the selective seascape far beyond the consequences of fishing or warming alone. The prospects are especially bleak for animals and plants compared with metabolically flexible microbes and algae. Halting and ultimately reversing these trends will require rapid and fundamental changes in fisheries, agricultural practice, and the emissions of greenhouse gases on a global scale. PMID:18695220

Colloquium paper: ecological extinction and evolution in the brave new ocean.

PubMed

Jackson, Jeremy B C

2008-08-12

The great mass extinctions of the fossil record were a major creative force that provided entirely new kinds of opportunities for the subsequent explosive evolution and diversification of surviving clades. Today, the synergistic effects of human impacts are laying the groundwork for a comparably great Anthropocene mass extinction in the oceans with unknown ecological and evolutionary consequences. Synergistic effects of habitat destruction, overfishing, introduced species, warming, acidification, toxins, and massive runoff of nutrients are transforming once complex ecosystems like coral reefs and kelp forests into monotonous level bottoms, transforming clear and productive coastal seas into anoxic dead zones, and transforming complex food webs topped by big animals into simplified, microbially dominated ecosystems with boom and bust cycles of toxic dinoflagellate blooms, jellyfish, and disease. Rates of change are increasingly fast and nonlinear with sudden phase shifts to novel alternative community states. We can only guess at the kinds of organisms that will benefit from this mayhem that is radically altering the selective seascape far beyond the consequences of fishing or warming alone. The prospects are especially bleak for animals and plants compared with metabolically flexible microbes and algae. Halting and ultimately reversing these trends will require rapid and fundamental changes in fisheries, agricultural practice, and the emissions of greenhouse gases on a global scale.

Spectral response of the coral rubble, living corals, and dead corals: study case on the Spermonde Archipelago, Indonesia

NASA Astrophysics Data System (ADS)

Nurdin, Nurjannah; Komatsu, Teruhisa; Yamano, Hiroya; Arafat, Gulam; Rani, Chair; Akbar AS, M.

2012-10-01

Coral reefs play important ecological services such as providing foods, biodiversity, nutrient recycling etc. for human society. On the other hand, they are threatened by human impacts such as illegal fishing and environmental changes such as rises of sea water temperature and sea level due to global warming. Thus, it is very important to monitor dynamic spatial distributions of coral reefs and related habitats such as coral rubble, dead coral, bleached corals, seagrass, etc. Hyperspectral data, in particular, offer high potential for characterizing and mapping coral reefs because of their capability to identify individual reef components based on their detailed spectral response. We studied the optical properties by measuring in situ spectra of living corals, dead coral and coral rubble covered with algae. Study site was selected in Spermonde archipelago, South Sulawesi, Indonesia because this area is included in the highest diversity of corals in the world named as Coral Triangle, which is recognized as the global centre of marine biodiversity and a global priority for conservation. Correlation analysis and cluster analysis support that there are distinct differences in reflectance spectra among categories. Common spectral characteristic of living corals, dead corals and coral rubble covered with algae was a reflectance minimum at 674 nm. Healthy corals, dead coral covered with algae and coral rubble covered with algae showed high similarity of spectral reflectance. It is estimated that this is due to photsynthetic pigments.

Instant transformation of learned repulsion into motivational "wanting".

PubMed

Robinson, Mike J F; Berridge, Kent C

2013-02-18

Learned cues for pleasant reward often elicit desire, which, in addicts, may become compulsive. According to the dominant view in addiction neuroscience and reinforcement modeling, such desires are the simple products of learning, coming from a past association with reward outcome. We demonstrate that cravings are more than merely the products of accumulated pleasure memories-even a repulsive learned cue for unpleasantness can become suddenly desired via the activation of mesocorticolimbic circuitry. Rats learned repulsion toward a Pavlovian cue (a briefly-inserted metal lever) that always predicted an unpleasant Dead Sea saltiness sensation. Yet, upon first reencounter in a novel sodium-depletion state to promote mesocorticolimbic reactivity (reflected by elevated Fos activation in ventral tegmentum, nucleus accumbens, ventral pallidum, and the orbitofrontal prefrontal cortex), the learned cue was instantly transformed into an attractive and powerful motivational magnet. Rats jumped and gnawed on the suddenly attractive Pavlovian lever cue, despite never having tasted intense saltiness as anything other than disgusting. Instant desire transformation of a learned cue contradicts views that Pavlovian desires are essentially based on previously learned values (e.g., prediction error or temporal difference models). Instead desire is recomputed at reencounter by integrating Pavlovian information with the current brain/physiological state. This powerful brain transformation reverses strong learned revulsion into avid attraction. When applied to addiction, related mesocorticolimbic transformations (e.g., drugs or neural sensitization) of cues for already-pleasant drug experiences could create even more intense cravings. This cue/state transformation helps define what it means to say that addiction hijacks brain limbic circuits of natural reward. Copyright © 2013 Elsevier Ltd. All rights reserved.

Germination, genetics, and growth of an ancient date seed.

PubMed

Sallon, Sarah; Solowey, Elaine; Cohen, Yuval; Korchinsky, Raia; Egli, Markus; Woodhatch, Ivan; Simchoni, Orit; Kislev, Mordechai

2008-06-13

An ancient date seed (Phoenix dactylifera L.) excavated from Masada and radiocarbon-dated to the first century Common Era was germinated. Climatic conditions at the Dead Sea may have contributed to the longevity of this oldest, directly dated, viable seed. Growth and development of the seedling over 26 months was compatible with normal date seedlings propagated from modern seeds. Preliminary molecular characterization demonstrated high levels of genetic variation in comparison to modern, elite date cultivars currently growing in Israel. As a representative of an extinct date palm population, this seedling can provide insights into the historic date culture of the Dead Sea region. It also has importance for seed banking and conservation and may be of relevance to modern date palm cultivation.

Prevalence of neurotoxic Clostridium botulinum type C in the gastrointestinal tracts of tilapia (Oreochromis mossambicus) in the Salton Sea.

PubMed

Nol, P; Rocke, T E; Gross, K; Yuill, T M

2004-07-01

Tilapia (Oreochromis mossambicus) have been implicated as the source of type C toxin in avian botulism outbreaks in pelicans (Pelecanus erythrorhynchos, Pelecanus occidentalis californicus) at the Salton Sea in southern California (USA). We collected sick, dead, and healthy fish from various sites throughout the Sea during the summers of 1999 through 2001 and tested them for the presence of Clostridium botulinum type C cells by polymerase chain reaction targeting the C(1) neurotoxin gene. Four of 96 (4%), 57 of 664 (9%), and five of 355 (1%) tilapia tested were positive for C. botulinum type C toxin gene in 1999, 2000, and 2001, respectively. The total number of positive fish was significantly greater in 2000 than in 2001 (P<0.0001). No difference in numbers of positives was detected between sick and dead fish compared with live fish. In 2000, no significant relationships were revealed among the variables studied, such as location and date of collection.

Prevalence of neurotoxic Clostridium botulinum type C in the gastrointestinal tracts of tilapis (Oreochromis mossambicus) in the Salton Sea

USGS Publications Warehouse

Nol, P.J.; Rocke, T.E.; Gross, K.; Yuill, Thomas M.

2004-01-01

Tilapia (Oreochromis mossambicus) have been implicated as the source of type C toxin in avian botulism outbreaks in pelicans (Pelecanus erythrorhynchos, Pelecanus occidentalis californicus) at the Salton Sea in southern California (USA). We collected sick, dead, and healthy fish from various sites throughout the Sea during the summers of 1999 through 2001 and tested them for the presence of Clostridium botulinum type C cells by polymerase chain reaction targeting the C1 neurotoxin gene. Four of 96 (4%), 57 of 664 (9%), and five of 355 (1%) tilapia tested were positive for C. botulinum type C toxin gene in 1999, 2000, and 2001, respectively. The total number of positive fish was significantly greater in 2000 than in 2001 (P<0.0001). No difference in numbers of positives was detected between sick and dead fish compared with live fish. In 2000, no significant relationships were revealed among the variables studied, such as location and date of collection.

Detection of sinkhole precursors along the Dead Sea, Israel by SAR interferometry

NASA Astrophysics Data System (ADS)

Nof, Ran; Baer, Gidon; Ziv, Alon; Eyal, Yehuda; Raz, Eli; Atzori, Simone; Salvi, Stefano

2013-04-01

The water level of the Dead Sea (Israel and Jordan) has been dropping at an increasing rate since the 1960s, exceeding a meter per year during the last decade. This water-level drop has triggered the formation of sinkholes and widespread land subsidence along the Dead Sea shorelines, resulting in severe economic loss and infrastructural damage. In this study, sinkhole-related precursory subsidence and the effects of human activities on sinkhole development are examined through Interferometric Synthetic Aperture Radar (InSAR) measurements and field surveys conducted in Israel during the year 2012. Interferograms were generated using the COSMO-SkyMed satellite images and a high-resolution (0.5 m/pixel) elevation model that was obtained from airborne Light Detection and Ranging (LiDAR). Thanks to this unique integration of high-resolution datasets, mm-scale subsidence may be resolved in both undisturbed and human-disturbed environments. A few months long precursory subsidence occurred in all three sinkhole sites reported in this study. The centers of the subsiding areas and successive sinkholes in a specific site show lateral migration, possibly due to progressive dissolution and widening of the underlying cavities. Certain human activities, such as filling of newly formed sinkholes by gravel, or mud injections into nearby drill holes, seem to enhance land subsidence, widen existing sinkholes or even generate new sinkholes.

Mitochondrial and morphological variation of Tilapia zillii in Israel.

PubMed

Szitenberg, Amir; Goren, Menachem; Huchon, Dorothée

2012-04-02

Tilapia zillii is widespread in the East Levant inland aquatic systems as well as in artificial water reservoirs. In this study we explore the genetic and morphological variation of this widespread species, using mitochondrial control region sequences and meristic characters. We examine the hypothesis that T. zillii's population structure corresponds to the four Israeli aquatic systems. Out of seven natural water bodies, only two were found to possess genetically divergent populations of T. zillii. In addition to its presence in fish farms, the species was found in two artificial recreational ponds which were supposed to have been stocked only with other fish species. In these two artificial habitats, the haplotype frequencies diverged significantly from those of natural populations. Finally, fish from the Dead Sea springs of Ne'ot HaKikar appear to differ both genetically and morphologically from fish of the same aquatic system but not from fish of other water systems. Our results show that the population structure of T. zillii does not match the geography of the Israeli water-basins, with the exception of the Dead Sea and Kishon River, when considering natural populations only. The absence of a significant divergence between basins is discussed. Our results and observations suggest that the Ne'ot HaKikar Dead Sea population and those of artificial ponds could have originated from the "hitchhiking" of T. zillii, at the expense of some other cultivated tilapiine species.

Intermittent balneotherapy at the Dead Sea area for patients with knee osteoarthritis.

PubMed

Sherman, Gilad; Zeller, Lior; Avriel, Avital; Friger, Michael; Harari, Marco; Sukenik, Shaul

2009-02-01

Balneotherapy, traditionally administered during a continuous stay at the Dead Sea area, has been shown to be effective for patients suffering from knee osteoarthritis. To evaluate the effectiveness of an intermittent regimen of balneotherapy at the Dead Sea for patients with knee osteoarthritis. Forty-four patients with knee osteoarthritis were included in a prospective randomized single-blind controlled study. The patients were divided into two groups: a treatment group (n=24), which were treated twice weekly for 6 consecutive weeks in a sulfur pool heated to 35-36 degrees C, and a control group (n=20) treated in a Jacuzzi filled with tap water heated to 35-36 degrees C. Participants were assessed by the Lequesne index of osteoarthritis severity, the WOMAC index, the SF-36 quality of health questionnaire, VAS scales for pain (completed by patients and physicians), and physical examination. A statistically significant improvement, lasting up to 6 months, was observed in the treatment group for most of the clinical parameters. In the control group the only improvements were in the SF-36 bodily pain scale at 6 months, the Lequesne index at 1 month and the WOMAC pain score at the end of the treatment period. Although the patients in the control group had milder disease, the difference between the two groups was not statistically significant. Intermittent balneotherapy appears to be effective for patients with knee osteoarthritis.

Study of observed microearthquakes at Masada Deep Borehole

NASA Astrophysics Data System (ADS)

Hofstetter, A.; Malin, P. E.

2017-12-01

Seismological measurements, conducted at great depths of several hundred of meters or even a few km, can provide useful information that one cannot get while conducting the measurements on the surface. We take advantage of Masada Deep borehole (MDBI), an abandoned oil well, for the installation of a seismometer at a large depth of 1,256 m (1,516 bsl). The station is located in the near vicinity of the East Masada fault, part of the Western Boundary Fault of the Dead Sea basin. We present seismic observations of microearthquakes which occurred along the Dead Sea fault (DSF). Many of them were not recorded by the Israel Seismic Network (ISN). The quiet site of the station has an obvious advantage in detection and identification of earthquakes and explosions. For example, the station detects about 30% more quarry explosions as compared to observations of the ISN. We demonstrate that borehole seismograms are clearer than the on-surface observations of nearby seismometer. We lowered the magnitude scale of observed events down to about M≈-3. Many of the earthquakes, sometimes clusters, occurred underneath the MDBI at depths of 10-25 km, having special signature. Using the cross-correlation technique we present several series of seismic activity either underneath the station or along the DSF. Frequency-magnitude relationship, known also as Gutenberg-Richter relationship, is somewhat higher than the determined value for the whole Dead Sea Fault.

Genetic connectivity between land and sea: the case of the beachflea Orchestia montagui (Crustacea, Amphipoda, Talitridae) in the Mediterranean Sea.

PubMed

Pavesi, Laura; Tiedemann, Ralph; De Matthaeis, Elvira; Ketmaier, Valerio

2013-04-25

We examined patterns of genetic divergence in 26 Mediterranean populations of the semi-terrestrial beachflea Orchestia montagui using mitochondrial (cytochrome oxidase subunit I), microsatellite (eight loci) and allozymic data. The species typically forms large populations within heaps of dead seagrass leaves stranded on beaches at the waterfront. We adopted a hierarchical geographic sampling to unravel population structure in a species living at the sea-land transition and, hence, likely subjected to dramatically contrasting forces. Mitochondrial DNA showed historical phylogeographic breaks among Adriatic, Ionian and the remaining basins (Tyrrhenian, Western and Eastern Mediterranean Sea) likely caused by the geological and climatic changes of the Pleistocene. Microsatellites (and to a lesser extent allozymes) detected a further subdivision between and within the Western Mediterranean and the Tyrrhenian Sea due to present-day processes. A pattern of isolation by distance was not detected in any of the analyzed data set. We conclude that the population structure of O. montagui is the result of the interplay of two contrasting forces that act on the species population genetic structure. On one hand, the species semi-terrestrial life style would tend to determine the onset of local differences. On the other hand, these differences are partially counter-balanced by passive movements of migrants via rafting on heaps of dead seagrass leaves across sites by sea surface currents. Approximate Bayesian Computations support dispersal at sea as prevalent over terrestrial regionalism.

Genetic connectivity between land and sea: the case of the beachflea Orchestia montagui (Crustacea, Amphipoda, Talitridae) in the Mediterranean Sea

PubMed Central

2013-01-01

Introduction We examined patterns of genetic divergence in 26 Mediterranean populations of the semi-terrestrial beachflea Orchestia montagui using mitochondrial (cytochrome oxidase subunit I), microsatellite (eight loci) and allozymic data. The species typically forms large populations within heaps of dead seagrass leaves stranded on beaches at the waterfront. We adopted a hierarchical geographic sampling to unravel population structure in a species living at the sea-land transition and, hence, likely subjected to dramatically contrasting forces. Results Mitochondrial DNA showed historical phylogeographic breaks among Adriatic, Ionian and the remaining basins (Tyrrhenian, Western and Eastern Mediterranean Sea) likely caused by the geological and climatic changes of the Pleistocene. Microsatellites (and to a lesser extent allozymes) detected a further subdivision between and within the Western Mediterranean and the Tyrrhenian Sea due to present-day processes. A pattern of isolation by distance was not detected in any of the analyzed data set. Conclusions We conclude that the population structure of O. montagui is the result of the interplay of two contrasting forces that act on the species population genetic structure. On one hand, the species semi-terrestrial life style would tend to determine the onset of local differences. On the other hand, these differences are partially counter-balanced by passive movements of migrants via rafting on heaps of dead seagrass leaves across sites by sea surface currents. Approximate Bayesian Computations support dispersal at sea as prevalent over terrestrial regionalism. PMID:23618554

50 CFR 82.5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Polar bear. Enhydra lutris Sea Otter. Odobenus rosmarus Walrus. Dugong dugong Dugong. Trichechus... means any specimen of the following species, whether alive or dead, or any part thereof, including but...

50 CFR 82.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Polar bear. Enhydra lutris Sea Otter. Odobenus rosmarus Walrus. Dugong dugong Dugong. Trichechus... means any specimen of the following species, whether alive or dead, or any part thereof, including but...

50 CFR 82.5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Polar bear. Enhydra lutris Sea Otter. Odobenus rosmarus Walrus. Dugong dugong Dugong. Trichechus... means any specimen of the following species, whether alive or dead, or any part thereof, including but...

50 CFR 82.5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Polar bear. Enhydra lutris Sea Otter. Odobenus rosmarus Walrus. Dugong dugong Dugong. Trichechus... means any specimen of the following species, whether alive or dead, or any part thereof, including but...

Development of the Inland Sea and its evaporites in the Jordan-Dead Sea Transform based on hydrogeochemical considerations and the geological consequences

NASA Astrophysics Data System (ADS)

Möller, Peter; Rosenthal, E.; Inbar, N.; Siebert, C.

2018-04-01

Differences in the distribution of Na/Cl, Br/Cl and Mg/Ca equivalent values suggest a morphotectonic barrier at Marma Feiyad dividing the Tertiary Inland Sea into two basins covering the region of the Jordan Valley, Middle East. Depending on the Tethys sea level, three phases of evaporation are distinguishable that are related to three sections of the drilling log of Zemah 1. In phase 1 and 3 only the northern basin was flooded. During phase 2 both basins were inundated, but halite mainly precipitated in the southern one. The halite deposition in one or the other basin by evaporation is estimated by applying a two-box model. The results are constrained by the average subduction rate of 700-875 m/Ma and characteristic Na/Cl values of 0.52 and 0.12 in the northern and southern basin, respectively. In different scenarios the sedimentation rates of halite and non-halite components are varied due to assumed halokinesis, reshuffling of salt and erosion of non-halite sediments. These simulations suggest that periods of 450-600 and 100-170 ka in the southern and northern basin were needed, until the Na/Cl values of 0.12 and 0.52 were, respectively, attained. The Inland Sea most probably existed for 2.2 ± 0.3 Ma between 8.5 and 6.3 Ma ago (Tortonian). It was terminated at the beginning of the Messinian crisis. In all simulations the drainage flux into the southern basin exceeded that into the northern basin, suggesting that the proto-Jordan River either did not exist at that time or did not discharge into the northern basin.

New Data on the Stable Isotopes and Vertical Distribution of Benthic Foraminifers in the Western Barents Sea

NASA Astrophysics Data System (ADS)

Yamskova, E.; Ivanova, E.; Risebrobakken, B.

2006-12-01

Despite a wide use of benthic foraminifers in paleoceanographic and paleoclimatic studies, notably in the Arctic seas, their ecology is still poorly known. We studied the distribution of living (Rose Bengal stained) and dead benthic foraminifers, as well as oxygen and carbon isotope composition of monospecific samples in the upper 10 cm of sediment in six box corers retrieved from the Western Barents Sea and the West Spitsbergen shelf during cruise 63 of RV Professor Shtokman. Living specimens of five common infaunal species and C. lobatulus, generally considered as epifaunal species, penetrate down to 7-10 cm except for the West Spitsbergen shelf where the habitat depth of all six species is limited to the upper 3-7 cm. The highest species diversity and amount of living specimens per 50 cm\\3 were found in the seasonally ice-free areas notably on the West Spitsbergen shelf and in the mouth of Isfjorden (Svalbard), areas characterized by very high primary production. In general, four species show higher abundance among living calcareous foraminifers as compared to the dead assemblages, whereas two species, C. reniforme and I. norcrossi, demonstrate an opposite behavior, i.e. are accumulated in the sediments. In most cases, the uppermost thin oxidized brownish layer of the sediment contains more living specimens and more fragile agglutinated foraminifers than olive-grey and grey (reduced) sediments below. If the latter two findings will be confirmed by further studies they may have important implications for paleoceanographic reconstructions as an evidence of a transformation of biocoenoses into thanathocoenoses in the Arctic seas. The epifunal species C. lobatulus demonstrate the heaviest (positive) carbon isotope values and the lowest oxygen isotope values as compared to all other species. Three infaunal species show relatively similar negative δ \\13 C values due to the microhabitat effect (i.e. oxidation of organic matter within the sediment). The heaviest oxygen isotope values are typical for N.labradoricum which is consistent with the previous studies. All species show heavier values in box-corers from the Persey Trough where the warm Atlantic water does not chill the sea floor unlike the other studied locations. Both δ 18 O and δ \\13 C measurements reveal different downcore trends with changing offsets between the species. This may be related to a vital effect of specific ontogenetic stages, but may also result from insufficient time resolution to obtain simultaneous data for all species.

The Hula Valley subsurface structure inferred from gravity data

USGS Publications Warehouse

Rybakov, M.; Fleischer, L.; ten Brink, Uri S.

2003-01-01

We use the 3-D gravity inversion technique to model the shape of the Hula basin, a pull-apart basin along the Dead Sea Transform. The interpretation was constrained using the Notera-3-well density logs and current geological knowledge. The model obtained by inversion shows a rhomb-shaped graben filled with approximately 4 km of young sediments in the deepest part of the basin. The reliability of this model was verified using 3-D forward modeling with an accuracy of 0.5 km. Curvature attributes of the gravity field depict the main fault pattern, suggesting that the Hula basin is a subsiding rhomb-shaped graben, bordered by steep-sided, deep basement faults on the western and eastern sides (Qiryat Shemona and Jordan River faults) and by gradual, en-echelon step faults on the southern and northern margins of the basin. ?? 2003 Laser Pages Publishing Ltd.

Amino Acid Coding Bias of the Hypersaline Dead Sea on an Environmental Scale

NASA Astrophysics Data System (ADS)

Rhodes, M. E.; Fitz-Gibbon, S.; Bodaker, I.; Beja, O.; Oren, A.; House, C.

2008-12-01

Metagenomic approaches can offer a broad overview of the microbial diversity in and environment and the metabolic processes performed within. At the most general level, knowing merely the GC content of an environment is enough to yield valuable insights as to the makeup of a microbial community. It has been documented that various environmental stresses, such as extreme acidity or salinity, can alter the usage of amino acids within members of an ecosystem. Here we explore the proportion of amino acids encoded within a variety of metagenomes including microbiomes from the human gut, the deep sea subsurface, acid mines, and the Dead Sea. Our primary focus is on strategies employed by hyperhalophiles to cope with the multimolar salinities of their environments. One of the approaches, used by archaea of the order Halobacteriales , as well as by a limited number of halophilc Bacteria is to accumulate comparable salt concentrations within their cytoplasm. It has been shown within individual species that the cytoplasmic proteins must then be modified in order to maintain their functionality. The changes include an overall increase in acidic amino acids coupled to a decrease in basic amino acids and a decrease in hydrophobic amino acids compensated for by an increase in the borderline hydrophobic amino acids Ser and Thr. We observed these trends within all fully sequenced hyperhalophilic Archaea and two distinct Dead Sea metagenomes (1992 and 2007). Additonally, the ratio of acidic to basic amino acids in the Dead Sea increased between the years 1992 and 2007, from 1.55 to 1.83. This corresponds to an increase of salinity of approximately 30 percent (from 270 ppt to 350 ppt) over the same time period. The shift in ratio of acidic to basic amino acids was not just observable in the metagenome as a whole and the archaeal subpopulation but was also pronounced in the bacterial subpopulation, from 1.27 to 1.62. This shift seems to indicate a restriction of the community from a relatively diverse hypersaline environment to one in which only the most extreme of hyperhalophiles could cope. It also suggests that the amino acid composition of the microbial community of an environment can serve as a proxy for salinity and potentially other environmental factors as well.

Alteration of glacigenic landforms by gravitational mass movements, Ragnarbreen and Ebbabreen, Svalbard

NASA Astrophysics Data System (ADS)

Ewertowski, Marek; Pleskot, Krzysztof; Tomczyk, Aleksandra

2015-04-01

The extensive recession of Svalbard's glaciers exposed areas containing large amount of dead-ice covered by relatively thin - usually less than a couple of meters - veneer of debris. This landscape can be very dynamic, mainly due to the mass movement processes and dead-ice melting. Continuous redistribution of sediments causes several phases of debris transfer and relief inversion. Hence, the primary glacial deposits released from ice are subsequently transferred by mass movement processes, until they finally reach more stable position. Investigations of dynamics of the mass movement and the way in which they alter the property of glacigenic sediments are therefore cruicial for proper understanding of sedimentary records of previous glaciations. The main objectives of this study were to: (1) quantify short-term dynamic of mass wasting processes; (2) investigate the transformation of the sediment's characteristic by mass wasting processes; (3) asses the contribution of different process to the overall dynamic of proglacial landscape. We focused on the mass-wasting processes in the forelands of two glaciers, Ebbabreen and Ragnarbreen, located near the Petuniabukta at the northern end of the Billefjorden, Spitsbergen. Repetitive topographic scanning was combined with sedimentological analysis of: grain size, clast shape in macro and micro scale and thin sections. Debris falls, slides, rolls and flows were the most important processes leading to reworking of glacigenic sediments and altering their properties. Contribution of different processes to the overall dynamic of the landforms was related mainly to the local conditions. Four different morphological types of sites were identified: (1) near vertical ice-cliffs covered with debris, transformed mainly due to dead-ice backwasting and debris falls and slides, (2) steep debris slopes with exposed ice-cores dominated by debris slides, (3) gentle sediment-mantled slopes transformed due to debris flows, and (4) non-active debris-mantled areas transformed only by dead-ice downwasting. The amount of volume loss due to the active mass movement processes and dead-ice melting (including both backwasting and downwasting) was up to more than 1.8 m a-1. In comparison, the amount of volume loss due to the dead-ice downwasting only was significantly lower at a maximum of 0.3 m a-1. The spatial and temporal distribution of volume changes, however, was quite diverse and for the most part related to local geomorphic conditions (e.g. slope gradient, occurrence of streams, and meltwater channels). We proposed a simplified model of spatio-temporal switching between stable and active conditions within the forelands of the studied glaciers. Transformations of landforms were attributed to the period of deglaciation and debris cover development. Stage 1 - shortly after deglaciation when the debris cover is thin (thinner than the permafrost active layer's thickness) mass movement processes become fairly common. They are facilitated by the dead-ice melting and steepness of the slopes. This stage can be observed in many lateral moraines, which are characterised by steep slopes, abundance of active mass movement processes, and by consequence a high degree of transformation. Stage 2 - ongoing mass-wasting processes lead to the transfer of sediments from steep slopes to more stable positions. As the thickness of the sediments increases, the debris cover starts to protect the dead-ice from melting and also contribute to the decrease in slope gradient. Thus, the resulting landscape is relatively stable and in equilibrium with current climatic and topographic conditions. This stage characterises most parts of the frontal (end) moraine complex of the studied glaciers; thus, their transformation rates are either very low or close to zero. Stage 3 - some parts of this stable landscape can be subsequently transformed again into an unstable state, mainly due to the effect of external factors such as streams or meltwater channels. This can lead to the development of mass movement processes and further slope instability, which could facilitate subsequent generation of debris flows. Stages described above can occur in a sort of spatio-temporal cycle, and, depending on local and external factors, the changes between stabilization of landforms and activation of mass flows can be repeated several times for any given area until the dead-ice is completely melted.

Impact of accelerated future global mean sea level rise on hypoxia in the Baltic Sea

NASA Astrophysics Data System (ADS)

Meier, H. E. M.; Höglund, A.; Eilola, K.; Almroth-Rosell, E.

2017-07-01

Expanding hypoxia is today a major threat for many coastal seas around the world and disentangling its drivers is a large challenge for interdisciplinary research. Using a coupled physical-biogeochemical model we estimate the impact of past and accelerated future global mean sea level rise (GSLR) upon water exchange and oxygen conditions in a semi-enclosed, shallow sea. As a study site, the Baltic Sea was chosen that suffers today from eutrophication and from dead bottom zones due to (1) excessive nutrient loads from land, (2) limited water exchange with the world ocean and (3) perhaps other drivers like global warming. We show from model simulations for the period 1850-2008 that the impacts of past GSLR on the marine ecosystem were relatively small. If we assume for the end of the twenty-first century a GSLR of +0.5 m relative to today's mean sea level, the impact on the marine ecosystem may still be small. Such a GSLR corresponds approximately to the projected ensemble-mean value reported by the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. However, we conclude that GSLR should be considered in future high-end projections (>+1 m) for the Baltic Sea and other coastal seas with similar hydrographical conditions as in the Baltic because GSLR may lead to reinforced saltwater inflows causing higher salinity and increased vertical stratification compared to present-day conditions. Contrary to intuition, reinforced ventilation of the deep water does not lead to overall improved oxygen conditions but causes instead expanded dead bottom areas accompanied with increased internal phosphorus loads from the sediments and increased risk for cyanobacteria blooms.

Sinai peninsula taken by the STS-112 crew

NASA Image and Video Library

2002-10-08

STS112-702-002 (7-18 October 2002) --- Egypt's triangular Sinai Peninsula lies in the center of this view, photographed from the Space Shuttle Atlantis, with the dark greens of the Nile delta lower right. In this southwesterly view, the Red Sea, with its characteristic parallel coastlines, stretches toward the top. At the bottom of the image, the Suez Canal appears as an irregular line joining the Red Sea to the Mediterranean Sea (lower left). The Dead Sea in central Israel, with its light blue salt ponds at the south end, appears on the left margin.

Anatomy of landslides along the Dead Sea Transform Fault System in NW Jordan

NASA Astrophysics Data System (ADS)

Dill, H. G.; Hahne, K.; Shaqour, F.

2012-03-01

In the mountainous region north of Amman, Jordan, Cenomanian calcareous rocks are being monitored constantly for their mass wasting processes which occasionally cause severe damage to the Amman-Irbid Highway. Satellite remote sensing data (Landsat TM, ASTER, and SRTM) and ground measurements are applied to investigate the anatomy of landslides along the Dead Sea Transform Fault System (DSTFS), a prominent strike-slip fault. The joints and faults pertinent to the DSTFS match the architectural elements identified in landslides of different size. This similarity attests to a close genetic relation between the tectonic setting of one of the most prominent fault zones on the earth and modern geomorphologic processes. Six indicators stand out in particular: 1) The fractures developing in N-S and splay faults represent the N-S lateral movement of the DSTFS. They governed the position of the landslides. 2) Cracks and faults aligned in NE-SW to NNW-SSW were caused by compressional strength. They were subsequently reactivated during extensional processes and used in some cases as slip planes during mass wasting. 3) Minor landslides with NE-SW straight scarps were derived from compressional features which were turned into slip planes during the incipient stages of mass wasting. They occur mainly along the slopes in small wadis or where a wide wadi narrows upstream. 4) Major landslides with curved instead of straight scarps and rotational slides are representative of a more advanced level of mass wasting. These areas have to be marked in the maps and during land management projects as high-risk area mainly and may be encountered in large wadis with steep slopes or longitudinal slopes undercut by road construction works. 5) The spatial relation between minor faults and slope angle is crucial as to the vulnerability of the areas in terms of mass wasting. 6) Springs lined up along faults cause serious problems to engineering geology in that they step up the behavior of marly interbeds to accelerate sliding during mass wasting. The most vulnerable areas prone to slope instabilities are those with compressional tectonics followed by extensional movements, with fault bound springs and smectite-bearing marly layers interbedded with pure massive limestones. The semi-arid to arid climate with periodic rainfalls combined with subsurface water circulation along the joints and faults can trigger mass wasting.

An Analysis of Sea Turtle Demographics along Maryland Shores, 1990-2015

NASA Astrophysics Data System (ADS)

Rhoades, C.; Driscoll, C.; Weschler, A.; Crawford, M.

2016-02-01

The Maryland Department of Natural Resources Marine Mammal and Sea Turtle Stranding Program was established in the fall of 1990, and responded to their first documented sea turtle stranding in the summer of 1991. Over this twenty-five year period, 575 dead strandings of sea turtles have been documented. This research project analyzes all sea turtle case files from the initiation of this program for the following parameters in order to associate stranding trends; species, location (Atlantic Ocean v. Chesapeake Bay), seasonality, length, relative age, condition code, and sex. Further understanding these protected species will assist in conserving their coastal ecosystem and securing these species a sustainable future. Along with the parameters previously discussed, this study will also consider the factors contributing to the animal's death, if determined. These potential causes incorporate natural causes such as disease, and also detail instances of human interaction, including: dredge takes, commercial or recreational fishing interaction, power plant entrainment, propeller and boat strikes. A total of approximately 17% of the dead stranded sea turtles Maryland Department of Natural Resources responded to were found to have some proven aspect of human interaction. Lastly, in order to further investigate for human interaction stomach contents were analyzed for plastics or other forms of marine debris. This project will contribute to MD DNR and NOAA's mission, goals, and objectives by further understanding these protected species in order to conserve their coastal ecosystem and secure these species a sustainable future.

50 CFR 230.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

.... Stinker means a dead, unclaimed whale found upon a beach, stranded in shallow water, or floating at sea... Americans under the control of a captain. Whaling village means any U.S. village recognized by the...

Growth of fungi in NaCl-MgSO4 brines

NASA Technical Reports Server (NTRS)

Siegel, S. M.; Siegel, B. Z.

1978-01-01

Previous investigations have shown that common fungi of the Penicillium-Aspergillus group can be grown in a variety of brines or on moist salt crystals. This simulates salt flats as well as sizeable waterbodies stabilized as saturated brines such as Don Juan Pond (Antarctica), the Great Salt Lake of Utah, and the Dead Sea in the Jordan Valley. In general, salt media rich in KCl are favored over other alkali halides; the media become more selective as the salt concentration rises and nutrient requirements become more complex. In the present paper, it is shown that media which resemble the Dead Sea salt mix can, in fact, support the growth of selected fungal strains, even in the absence of reduced organic nutrients other than glucose. Such media may serve as models for localized microhabitats on Mars.

Mitochondrial and morphological variation of Tilapia zillii in Israel

PubMed Central

2012-01-01

Background Tilapia zillii is widespread in the East Levant inland aquatic systems as well as in artificial water reservoirs. In this study we explore the genetic and morphological variation of this widespread species, using mitochondrial control region sequences and meristic characters. We examine the hypothesis that T. zillii's population structure corresponds to the four Israeli aquatic systems. Results Out of seven natural water bodies, only two were found to possess genetically divergent populations of T. zillii. In addition to its presence in fish farms, the species was found in two artificial recreational ponds which were supposed to have been stocked only with other fish species. In these two artificial habitats, the haplotype frequencies diverged significantly from those of natural populations. Finally, fish from the Dead Sea springs of Ne'ot HaKikar appear to differ both genetically and morphologically from fish of the same aquatic system but not from fish of other water systems. Conclusions Our results show that the population structure of T. zillii does not match the geography of the Israeli water-basins, with the exception of the Dead Sea and Kishon River, when considering natural populations only. The absence of a significant divergence between basins is discussed. Our results and observations suggest that the Ne'ot HaKikar Dead Sea population and those of artificial ponds could have originated from the "hitchhiking" of T. zillii, at the expense of some other cultivated tilapiine species. PMID:22469095

Benthic foraminifera from the Arabian Sea oxygen minimum zone: towards a paleo-oxygenation proxy.

NASA Astrophysics Data System (ADS)

Clemence, Caulle; Meryem, Mojtahid; Karoliina, Koho; Andy, Gooday; Gert-Jan, Reichart; Gerhard, Schmiedl; Frans, Jorissen

2014-05-01

Benthic foraminifera from the Arabian Sea oxygen minimum zone: towards a paleo-oxygenation proxy. C. Caulle1, M. Mojtahid1, K. Koho2,3, A. Gooday4, G. J. Reichart2,3, G. Schmiedl5, F. Jorissen1 1UMR CNRS 6112 LPG-BIAF, University of Angers, 2 bd Lavoisier, 49045 Angers Cedex 2Utrecht University, Faculty of Geosciences, Department of Earth Sciences, Budapestlaan 4, 3584 CD Utrecht, The Netherlands 3Royal Netherland Institute for Sea Research (Royal NIOZ), Landsdiep 4, 1797 SZ 't Horntje (Texel) 4Southampton Oceanography Centre, Empress Dock, European Way, Southampton SO14 3ZH, UK 5Department of Geosciences, University of Hamburg, Bundesstraße 55, 20146 Hamburg, Germany The thermohaline circulation oxygenates the deep ocean sediment and therefore enables aerobic life on the sea-floor. In the past, interruption of this deep water formation occurred several times causing hypoxic to anoxic conditions on the sea-floor leading to major ecological turnover. A better understanding of the interaction between climate and bottom water oxygenation is therefore essential in order to predict future oceanic responses. Presently, permanent (stable over decadal timescale) low-oxygen conditions occur naturally at mid-water depths in the northern Indian Ocean (Arabian Sea). Oxygen Minimum Zones (OMZ) are key areas to understand the hypoxic-anoxic events and their impact on the benthic ecosystem. In this context, a good knowledge of the ecology and life cycle adaptations of the benthic foraminiferal assemblages living in these low oxygen areas is essential. A series of multicores were recovered from three transects showing an oxygen gradient across the OMZ: the Murray Ridge, the Oman margin and the Indian margin. The stations located at the same depths showed slightly different oxygen concentrations and large differences in organic matter content. These differences are mainly related to the geographic location in the Arabian Sea. We investigated at these stations live and dead benthic foraminiferal faunas. At each location, faunal diversity seems to be controlled by bottom-water oxygen content; limited diversity corresponding to low oxygen content. Foraminiferal abundances reflect organic matter quantity and quality; higher organic matter quality and quantity are related to higher foraminiferal abundances. When comparing the three study areas, similar foraminiferal species (live and dead) are observed suggesting that benthic foraminifera from the Arabian Sea predominantly respond to bottom-water oxygenation. Based on these observations, we aim to develop a paleo-oxygenation proxy based on live, dead and fossil faunas resulting from both our study and previous studies in the Arabian Sea.

Last interglacial (MIS5e) sea-levels and uplift along the north-east Gulf of Aqaba

NASA Astrophysics Data System (ADS)

BAR (KOHN), N.; Stein, M.; Agnon, A.; Yehudai, M.; Lazar, B.; Shaked, Y.

2014-12-01

An uplifted flight of coral reef terraces, extending along the north-east margin of the Gulf of Aqaba (GOA), provides evidence for uplift rates and sea level high stands. GOA fills a narrow and deep tectonic depression lying along the southern sector of the Dead Sea Transform where it meets the Red Sea. This special configuration of the GOA and its latitude turn it into a dependable paleo-sea level monitor, sensitive only to global eustatic changes and local tectonic movements. A sequence of five uplifted coral reef terraces were mapped and characterized on basis of morphology and reef-facies, and their elevation above the present sea level was determined. The fossil reefs studied comprise fringing reefs, some with clear reef-structure that includes a reef flat and a shallow back lagoon. Most outcrops in the study area represent a transgressive sequence in which, during its highest stand, formed fringing reef terraces. We use U-Th ages of fossil corals samples found in growth position at various terraces. Corals from three uplifted reef terraces, R1, R2, and R3 were dated to the last interglacial period particularly to marine isotope stage (MIS) 5e. These ages were achieved from mainly calcitic corals (recrystallized in a freshwater phreatic environment). A few ages were derived from aragonite corals. The three terraces represent three sub-stages within MIS5e: R3 formed during a short standstill at ~130 ka BP; R2 formed during a long and steady standstill between ~128 to ~121 ka BP; and R1 represents a short standstill at ~117 ka BP. Assuming that terrace reef flats represent past sea level high stands, we calculated the coast average uplift rate and constrained the original terraces elevations. The reconstructed eustatic sea level variation during MIS 5e at GOA resembles observations from reef terraces in other locations. Combined, all indicate a significant sea-level rise from the MIS 6 low stand at ~134-130 ka and followed by a long and stable sea level high stand between ~128 to ~121 ka, representing a major reef building period. The long and stable sea level was followed by additional sea-level rise at ~118-116 ka that transgressed over the "stable reefs".

Variability of intertidal foraminferal assemblages in a salt marsh, Oregon, USA

USGS Publications Warehouse

Milker, Yvonne; Horton, Benjamin P.; Nelson, Alan R.; Engelhart, Simon E.; Witter, Robert C.

2015-01-01

We studied 18 sampling stations along a transect to investigate the similarity between live (rose Bengal stained) foraminiferal populations and dead assemblages, their small-scale spatial variations and the distribution of infaunal foraminifera in a salt marsh (Toms Creek marsh) at the upper end of the South Slough arm of the Coos Bay estuary, Oregon, USA. We aimed to test to what extent taphonomic processes, small-scale variability and infaunal distribution influence the accuracy of sea-level reconstructions based on intertidal foraminifera. Cluster analyses have shown that dead assemblages occur in distinct zones with respect to elevation, a prerequisite for using foraminifera as sea-level indicators. Our nonparametric multivariate analysis of variance showed that small-scale spatial variability has only a small influence on live (rose Bengal stained) populations and dead assemblages. The dissimilarity was higher, however, between live (rose Bengal stained) populations in the middle marsh. We observed early diagenetic dissolution of calcareous tests in the dead assemblages. If comparable post-depositional processes and similar minor spatial variability also characterize fossil assemblages, then dead assemblage are the best modern analogs for paleoenvironmental reconstructions. The Toms Creek tidal flat and low marsh vascular plant zones are dominated by Miliammina fusca, the middle marsh is dominated by Balticammina pseudomacrescens and Trochammina inflata, and the high marsh and upland–marsh transition zone are dominated by Trochamminita irregularis. Analysis of infaunal foraminifera showed that most living specimens are found in the surface sediments and the majority of live (rose Bengal stained) infaunal specimens are restricted to the upper 10 cm, but living individuals are found to depths of 50 cm. The dominant infaunal specimens are similar to those in the corresponding surface samples and no species have been found living solely infaunally. The total numbers of infaunal foraminifera are small compared to the total numbers of dead specimens in the surface samples. This suggests that surface samples adequately represent the modern intertidal environment in Toms Creek.

The Tiberias Basin salt deposits and their effects on lake salinity

NASA Astrophysics Data System (ADS)

Inbar, Nimrod; Rosenthal, Eliahu; Möller, Peter; Yellin-Dror, Annat; Guttman, Josef; Siebert, Christian; Magri, Fabien

2015-04-01

Lake Tiberias is situated in one of the pull-apart basins comprising the Dead Sea transform. The Tiberias basin extends along the northern boundary of the Lower Jordan Rift Valley (LJRV) which is known for its massive salt deposits, mostly at its southern end, at the Dead Sea basin. Nevertheless, prior to the drilling of Zemah-1 wildcat, drilled close to the southern shores of Lake Tiberias, the Tiberias Basin was considered rather shallow and free of salt deposits (Starinsky, 1974). In 1983, Zemah-1 wildcat penetrated 2.8 km thick sequence of sedimentary and magmatic rocks of which 980m are salt deposits (Marcus et al., 1984). Recent studies, including the presented geophysical investigations, lay out the mechanisms of salt deposition in the Tiberias basin and estimate its abundance. Supported by seismic data, our interpreted cross-sections display relatively thick salt deposits distributed over the entire basin. Since early days of hydrological research in the area, saline springs are known to exist at Lake Tiberias' surroundings. Water temperatures in some of the springs indicate their origin to be at depths of 2-3 km (Simon and Mero, 1992). In the last decade, several studies suggested that the salinity of springs may be attributed, at least partially, to the Zemah-1 salt deposits. Chemical justification was attributed to post-halite minerals which were thought to be present among those deposits. This hypothesis was never verified. Moreover, Möller et al. (2011) presented a calculation contradicting this theory. In addition to the geophysical investigations, numerical models of thermally driven flow, examine the possible fluid dynamics developing near salt deposits below the lake and their interactions with springs along the lakeshore (Magri et al., 2015). It is shown that leached halite is too heavy to reach the surface. However, salt diffusing from shallow salt crest may locally reach the western side of the lakeshore. References Magri, F., N. Inbar,C. Siebert, E. Rosenthal, J. Guttman and P. Möller (2015) Transient simulations of large-scale hydrogeological processes causing temperature and salinity anomalies in the Tiberias Basin, Journal of Hydrology, Volume 520, Pages 342-355, Marcus, E., Y. Slager, S. Ben-Zaken, and I. Y. Indik (1984), Zemah 1, Geological Complition ReportRep. 84/11, 108 pp, Oil Exploration (Investments) LTD, Tel Aviv. Möller, P., C. Siebert, S. Geyer, N. Inbar, E. Rosenthal, A. Flexer, and M. Zilberbrand (2011), Relationships of Brines in the Kinnarot Basin, Jordan-Dead Sea Rift Valley, Geofluids (doi: 10.1111/j.1468-8123.2011.00353.x). Simon, E., and F. Mero (1992), The salinization mechanism of Lake Kinneret, J. Hydrol., 138, 327-343. Starinsky, A. (1974), Relationship between Ca-Chloride Brines and Sedimentary Rocks in Israel, PhD thesis, 84 pp, Hebrew University, Jerusalem.

Earth Observation taken during the 41G mission

NASA Image and Video Library

2009-06-25

41G-120-056 (October 1984) --- Parts of Israel, Lebanon, Palestine, Syria and Jordan and part of the Mediterranean Sea are seen in this nearly-vertical, large format camera's view from the Earth-orbiting Space Shuttle Challenger. The Sea of Galilee is at center frame and the Dead Sea at bottom center. The frame's center coordinates are 32.5 degrees north latitude and 35.5 degrees east longitude. A Linhof camera, using 4" x 5" film, was used to expose the frame through one of the windows on Challenger's aft flight deck.

Earth Observation taken during Joint Operations

NASA Image and Video Library

2009-07-23

S127-E-008034 (23 July 2009) --- Part of the Dead Sea and parts of Israel and Jordan were photographed with a digital still camera by one of the crew members aboard the Space Shuttle Endeavour on July 23, 2009.

Mechanism of Sinkhole Formation in the Ghor Al-Haditha Based on Geophysical Data

NASA Astrophysics Data System (ADS)

Akawwi, E.; Al-Zoubi, A.; Abueadas, A.; Eppelbaum, L.; Ezersky, M.; Levi, E.; Legchenko, A.; Boucher, M.

2012-04-01

Dead Sea sinkholes have been forming along the Dead Sea coastal areas in both Israel and Jordan during three last decades. Sinkholes developing in the Ghor Al-Haditha Area affect in roads, agriculture lands, and building foundations by the sudden collapse of the ground surface and cracks with different sizes and depths. If mechanism of sinkhole formation along western Dead Sea shore has been studied goodly enough eastern side requires additional interpretation of data available. The situation in Jordan is complicated by complicated geology and absence of data on salt layers from the verification boreholes. The exposed walls of sinkholes also demonstrated that much of this geological sequence near the surface is composed of sand, silty sand and gravel, in addition to some evaporates minerals (dominantly salt and gypsum). It is understood today that sinkholes are formed within Holocene salt layers located after seismic refraction data at shallow depths of 40-50 meters. Different models suggested by different investigating groups have been suggested. There are models based on surface measurements (InSAR Radar), Microgravity modeling, visual inspection of sinkhole sites etc. The flushing model based on the assumption that turbulent underground water flows associated with a massive mass transport of insoluble fractions (clay and silt) have produced subsurface hollows. These expand upwards and finally appear on the surface as sinkholes. We develop model based on different geophysical studies using seismic reflection and refraction methods, Magnitometry and Microgravity, Electric resistivity Tomography (ERT) and Ground Penetrating Radar (GPR), Magnetic Resonance Sounding (MRS) method, Transient Electromagnetic (TEM) method etc. These data allows suggesting the geophysical model of sinkhole formation mechanism. Our model considers the salt edge as a major factor of sinkhole formation with some features associated with tectonic setting and hydrogeology. The salt model is based on the assumption that salt edge is dissolved by flowing water, artesian water and springs. The salt cavern causes the collapse of the overlain strata and finally appears on the surface. It is suggested also that collapse of pre-existing cavities can take place because of the drop in the Dead Sea level. Acknowledgements This publication was made possible through support provided by the U.S. Agency for International Development (USAID) and MERC Program under terms of Award No M27-050.

Possible connection between large volcanic eruptions and level rise episodes in the Dead Sea Basin

NASA Astrophysics Data System (ADS)

Bookman, R.; Filin, S.; Avni, Y.; Rosenfeld, D.; Marco, S.

2014-12-01

The June 1991 Pinatubo volcanic eruption perturbed the atmosphere, triggering short-term worldwide changes in climate. The following winter was anomalously wet in the Levant, with a ~2-meter increase in the Dead Sea level that created a morphological terrace along the lake's shore. Given the global effects of volcanogenic aerosols, we tested the hypothesis that the 1991-92 shore terrace is a modern analogue to the linkage between past volcanic eruptions and a sequence of shore terraces in the Dead Sea Basin. Analysis of precipitation series from Jerusalem showed a significant positive correlation between the Dust Veil Index (DVI) of the modern eruptions and annual rainfall. The DVI was found to explain nearly 50% of the variability in the annual rainfall, such that greater DVI means more rainfall. Other factors that may affect the annual rainfall in the region as the Southern Oscillation Index (SOI) and the North Atlantic oscillations (NAO) were incorporated along with the DVI in a linear multiple regression model. It was found that the NAO did not contribute anything except for increased noise, but the added SOI increased the explained variability of rainfall to more than 60%. Volcanic eruptions with a VEI of 6, as in the Pinatubo, occurred about once a century during the Holocene and the last glacial-interglacial cycle. This occurrence is similar to the frequency of shore terrace build-up during the Lake Lisan desiccation. Sixteen shore terraces, detected using airborne laser scanning data, were interpreted as indicating short-term level rises due to episodes of enhanced precipitation and runoff during the dramatic drop in Lake Lisan's (palaeo-Dead Sea) level at the end of the LGM. The terraces were compared with a time series of volcanogenic sulfate from the GISP2 record, and similar numbers of sulfate concentration peaks and terraces were found. Furthermore, a significant correlation was found between SO4 concentration peaks and the terraces heights. This correlation may indicate a link between the explosivity, magnitude of stratospheric injection, and the impact on the northern hemisphere water balance. The record of such short-term climato-hydrological effects is made possible by the dramatic desiccation of Lake Lisan. Detailed records of such events provide a demonstration of global climatic teleconnections.

3D structure of a complex of transform basins from gravity data, a case study from the central Dead Sea fault

NASA Astrophysics Data System (ADS)

Rosenthal, Michal; Schattner, Uri; Ben-Avraham, Zvi

2017-04-01

The Kinneret-Bet She'an (KBS) basin complex comprises the Sea of Galilee, Kinarot, and Bet She'an sub-basins. The complex developed at the intersection between two major tectonic boundaries: the Oligo-Miocene Azraq-Sirhan failed rift, that later developed into the southern Galilee basins and Carmel-Gilboa fault system; and the Dead Sea fault (DSF) plate boundary that developed since the Miocene. Despite numerous studies, KBS still remains one of the enigmatic basin complexes. Its structure, stratigraphy and development are vaguely understood - both inside the basin and in correlation with its surroundings. Our study presents a new and comprehensive 3D model for the structure of KBS complex. It is based on all available gravity measurements, adopted from the national gravity database, and new gravity measurements, collected in cooperation with the Geological Survey of Israel and funded by the Ministry of National Infrastructure, Energy and Water Resources. The gravity data were integrated with constraints from boreholes, surface geology, seismic surveys, potential field studies and teleseismic tomography. The dense distribution of gravity data [1] provides suitable coverage for modeling the deep structure in three dimensions. The model details the spatial distribution, depth, thickness and density of the following regional units within the KBS complex and across its surroundings: upper crust, pre-Senonian sediments, Senonian and Cenozoic sediments, Miocene volcanics, Pliocene and Quaternary volcanics. Additional local units include salt, gabbro and pyroclasts. Results indicate that the KBS complex comprises two sub-basins separated by a structural saddle: Kinneret-Kinarot ( 6-7 km deep, 45 km long) and Bet She'an ( 4 km deep, 10 km long) sub-basin. A 500 m thick layer of Miocene volcanics appears across the Bet She'an sub-basin, yet missing from the Kinneret-Kinarot sub-basin. Between the basins Zemah-1 borehole penetrated a salt unit. The model indicates that this unit is a part of a thick (1250 m) dome-shaped, perhaps diapiric, structure. A relatively thin (350 m) salt unit fills the Kinneret-Kinarot sub-basin. Above, a 700 m thick layer of Pliocene volcanics fills the entire KBS complex. These volcanics are uplifted in the Zemah area by 200 m. The Pliocene volcanics dip northward from Zemah towards the center of the Sea of Galilee, and further north the Pliocene volcanics dip southward from Korazim towards the center of the Sea of Galilee. The depth differences exceed 3 km across a distance of 15 km, forming a 11° slope below the younger Quaternary fill of the basin. A low-density, probably pyroclastic, lens is calculated within the uppermost 2 km of the Sea of Galilee fill. Scenarios for the development of the basin are discussed. [1] Rosenthal, M., Segev, A., Rybakov, M., Lyakhovsky, V. and Ben-Avraham, Z. (2015) The deep structure and density distribution of northern Israel and its surroundings. GSI Report No. GSI/12/2015, 33 pages, Jerusalem.

The Living Dead: Transformative Experiences in Modelling Natural Selection

ERIC Educational Resources Information Center

Petersen, Morten Rask

2017-01-01

This study considers how students change their coherent conceptual understanding of natural selection through a hands-on simulation. The results show that most students change their understanding. In addition, some students also underwent a transformative experience and used their new knowledge in a leisure time activity. These transformative…

Discrimination of shot-noise-driven Poisson processes by external dead time - Application of radioluminescence from glass

NASA Technical Reports Server (NTRS)

Saleh, B. E. A.; Tavolacci, J. T.; Teich, M. C.

1981-01-01

Ways in which dead time can be used to constructively enhance or diminish the effects of point processes that display bunching in the shot-noise-driven doubly stochastic Poisson point process (SNDP) are discussed. Interrelations between photocount bunching arising in the SNDP and the antibunching character arising from dead-time effects are investigated. It is demonstrated that the dead-time-modified count mean and variance for an arbitrary doubly stochastic Poisson point process can be obtained from the Laplace transform of the single-fold and joint-moment-generating functions for the driving rate process. The theory is in good agreement with experimental values for radioluminescence radiation in fused silica, quartz, and glass, and the process has many applications in pulse, particle, and photon detection.

Transcriptome-wide analysis of DEAD-box RNA helicase gene family in an Antarctic psychrophilic alga Chlamydomonas sp. ICE-L.

PubMed

Liu, Chenlin; Huang, Xiaohang

2015-09-01

DEAD-box RNA helicase family proteins have been identified in almost all living organisms. Some of them play a crucial role in adaptation to environmental changes and stress response, especially in the low-temperature acclimation in different kinds of organisms. Compared with the full swing study in plants and bacteria, the characters and functions of DEAD-box family proteins had not been surveyed in algae. To identify genes critical for freezing acclimation in algae, we screened DEAD-box RNA helicase genes from the transcriptome sequences of a psychrophilic microalga Chlamydomonas sp. ICE-L which was isolated from Antarctic sea ice. Totally 39 DEAD-box RNA helicase genes had been identified. Most of the DEAD-box RNA helicase have 1:1 homologous relationships in Chlamydomonas reinhardtii and Chlamydomonas sp. ICE-L with several exceptions. The homologous proteins in ICE-L to the helicases critical for cold or freezing tolerance in Arabidopsis thaliana had been identified based on phylogenetic comparison studies. The response of these helicase genes is not always identical in the Chlamydomonas sp. ICE-L and Arabidopsis under the same low-temperature treatment. The expression of several DEAD-box RNA helicase genes including CiRH5, CiRH25, CiRH28, and CiRH55 were significantly up-regulated under freezing treatment of ICE-L and their function in freezing acclimation of ICE-L deserved further investigation.

Parasites and associated pathology observed in pinnipeds stranded along the Oregon coast.

PubMed

Stroud, R K

1978-07-01

Forty-two seals and sea lions found dead along the Oregon Coast were examined for parasites and associated pathology. Nematode infections of the lung and/or gastrointestinal tract were the primary cause of death in 5 of 42 animals examined. New distribution records were established for Pricetrema zalophi and Zalophotrema hepaticum. New host records include Z. hepaticum and Diphyllobothrium cordatum in the Steller's sea lion (Eumetopias jubatus); Nanophyetus salmincola in the California sea lion (Zalophus californianus); P. zalophi in the harbor seal (Phoca vitulina); and P. zalophi, Trigonocotyle sp. and Otostrongylus circumlitus in the northern elephant seal (Mirounga angustirostris).

Setting Dead at Zero: Applying Scale Properties to the QALY Model.

PubMed

Roudijk, Bram; Donders, A Rogier T; Stalmeier, Peep F M

2018-04-01

Scaling severe states can be a difficult task. First, the method of measurement affects whether a health state is considered better or worse than dead. Second, in discrete choice experiments, different models to anchor health states on 0 (dead) and 1 (perfect health) produce varying amounts of health states worse than dead. Within the context of the quality-adjusted life-year (QALY) model, this article provides insight into the value assigned to dead and its consequences for decision making. Our research questions are 1) what are the arguments set forth to assign dead the number 0 on the health-utility scale? And 2) what are the effects of the position of dead on the health-utility scale on decision making? A literature review was conducted to explore the arguments set forth to assign dead a value of 0 in the QALY model. In addition, scale properties and transformations were considered. The review uncovered several practical and theoretical considerations for setting dead at 0. In the QALY model, indifference between 2 health episodes is not preserved under changes of the origin of the duration scale. Ratio scale properties are needed for the duration scale to preserve indifferences. In combination with preferences and zero conditions for duration and health, it follows that dead should have a value of 0. The health-utility and duration scales have ratio scale properties, and dead should be assigned the number 0. Furthermore, the position of dead should be carefully established, because it determines how life-saving and life-improving values are weighed in cost-utility analysis.

An example of aerosol pattern variability over bright surface using high resolution MODIS MAIAC: The eastern and western areas of the Dead Sea and environs.

PubMed

Lee, Sever; Pinhas, Alpert; Alexei, Lyapustin; Yujie, Wang; Alexandra, Chudnovsky A

2017-09-01

The extreme rate of evaporation of the Dead Sea (DS) has serious implicatios for the surrounding area, including atmospheric conditions. This study analyzes the aerosol properties over the western and eastern parts of the DS during the year 2013, using MAIAC (Multi-Angle Implementation of Atmospheric Correction) for MODIS, which retrieves aerosol optical depth (AOD) data at a resolution of 1km. The main goal of the study is to evaluate MAIAC over the study area and determine, for the first time, the prevailing aerosol spatial patterns. First, the MAIAC-derived AOD data was compared with data from three nearby AERONET sites (Nes Ziona - an urban site, and Sede Boker and Masada - two arid sites), and with the conventional Dark Target (DT) and Deep Blue (DB) retrievals for the same days and locations, on a monthly basis throughout 2013. For the urban site, the correlation coefficient (r) for DT/DB products showed better performance than MAIAC (r=0.80, 0.75, and 0.64 respectively) year-round. However, in the arid zones, MAIAC showed better correspondence to AERONET sites than the conventional retrievals (r=0.58-0.60 and 0.48-0.50 respectively). We investigated the difference in AOD levels, and its variability, between the Dead Sea coasts on a seasonal basis and calculated monthly/seasonal AOD averages for presenting AOD patterns over arid zones. Thus, we demonstrated that aerosol concentrations show a strong preference for the western coast, particularly during the summer season. This preference, is most likely a result of local anthropogenic emissions combined with the typical seasonal synoptic conditions, the Mediterranean Sea breeze, and the region complex topography. Our results also indicate that a large industrial zone showed higher AOD levels compared to an adjacent reference-site, i.e., 13% during the winter season.

Postmortem examination of Australian sea snakes ( Hydrophiinae): Anatomy and common pathologic conditions.

PubMed

Gillett, Amber K; Ploeg, Richard; Flint, Mark; Mills, Paul C

2017-09-01

There is limited published information about disease in wild sea snakes and no standardized guideline for postmortem examination of sea snakes. Identifying causes of morbidity and mortality of marine vertebrate species has been pivotal to understanding disease factors implicated in stranding events and assisting with the formulation of conservation plans. Additionally, postmortem findings can provide valuable information on life history traits and the ecology of these reclusive species. Sick, moribund, or dead sea snakes are intermittently washed ashore along Australian and international beaches and provide an opportunity to examine a subset of the population and identify causes of population decline. We present an illustrated description of sea snake anatomy and describe a systematic approach to postmortem examination of sea snakes. We describe common pathologic conditions identified from clinical and postmortem examinations of stranded Australian sea snakes from southeast Queensland. Notable pathologic conditions include traumatic injury, inflammatory conditions, parasitic infections, and neoplasia.

Submarine and Autonomous Vessel Proliferation: Implications for Future Strategic Stability at Sea

DTIC Science & Technology

2012-12-01

missile.4 These important details of the legacy of the Cold War at sea are too often forgotten in today’s retelling of the story . Yet, as CDR (USN...vented deadly fumes. The damaged and still-burning vessel was scuttled with its nuclear weapons and reactors aboard. 8 Pavel Podvig, ed., Russian ...exception of China in the 1950s,13 the Russians generally did not provide production technology and refrained from offering sophisticated offensive systems

Evaporation estimates from the Dead Sea and their implications on its water balance

NASA Astrophysics Data System (ADS)

Oroud, Ibrahim M.

2011-12-01

The Dead Sea (DS) is a terminal hypersaline water body situated in the deepest part of the Jordan Valley. There is a growing interest in linking the DS to the open seas due to severe water shortages in the area and the serious geological and environmental hazards to its vicinity caused by the rapid level drop of the DS. A key issue in linking the DS with the open seas would be an accurate determination of evaporation rates. There exist large uncertainties of evaporation estimates from the DS due to the complex feedback mechanisms between meteorological forcings and thermophysical properties of hypersaline solutions. Numerous methods have been used to estimate current and historical (pre-1960) evaporation rates, with estimates differing by ˜100%. Evaporation from the DS is usually deduced indirectly using energy, water balance, or pan methods with uncertainty in many parameters. Accumulated errors resulting from these uncertainties are usually pooled into the estimates of evaporation rates. In this paper, a physically based method with minimum empirical parameters is used to evaluate historical and current evaporation estimates from the DS. The more likely figures for historical and current evaporation rates from the DS were 1,500-1,600 and 1,200-1,250 mm per annum, respectively. Results obtained are congruent with field observations and with more elaborate procedures.

Bacteria Contribute to Sediment Nutrient Release and Reflect Progressed Eutrophication-Driven Hypoxia in an Organic-Rich Continental Sea

PubMed Central

Sinkko, Hanna; Lukkari, Kaarina; Sihvonen, Leila M.; Sivonen, Kaarina; Leivuori, Mirja; Rantanen, Matias; Paulin, Lars; Lyra, Christina

2013-01-01

In the sedimental organic matter of eutrophic continental seas, such as the largest dead zone in the world, the Baltic Sea, bacteria may directly participate in nutrient release by mineralizing organic matter or indirectly by altering the sediment’s ability to retain nutrients. Here, we present a case study of a hypoxic sea, which receives riverine nutrient loading and in which microbe-mediated vicious cycles of nutrients prevail. We showed that bacterial communities changed along the horizontal loading and vertical mineralization gradients in the Gulf of Finland of the Baltic Sea, using multivariate statistics of terminal restriction fragments and sediment chemical, spatial and other properties of the sampling sites. The change was mainly explained by concentrations of organic carbon, nitrogen and phosphorus, which showed strong positive correlation with Flavobacteria, Sphingobacteria, Alphaproteobacteria and Gammaproteobacteria. These bacteria predominated in the most organic-rich coastal surface sediments overlain by oxic bottom water, whereas sulphate-reducing bacteria, particularly the genus Desulfobacula, prevailed in the reduced organic-rich surface sediments in the open sea. They correlated positively with organic nitrogen and phosphorus, as well as manganese oxides. These relationships suggest that the bacterial groups participated in the aerobic and anaerobic degradation of organic matter and contributed to nutrient cycling. The high abundance of sulphate reducers in the surficial sediment layers reflects the persistence of eutrophication-induced hypoxia causing ecosystem-level changes in the Baltic Sea. The sulphate reducers began to decrease below depths of 20 cm, where members of the family Anaerolineaceae (phylum Chloroflexi) increased, possibly taking part in terminal mineralization processes. Our study provides valuable information on how organic loading affects sediment bacterial community compositions, which consequently may maintain active nutrient recycling. This information is needed to improve our understanding on nutrient cycling in shallow seas where the dead zones are continuously spreading worldwide. PMID:23825619

Seismic surface-wave prospecting methods for sinkhole hazard assessment along the Dead Sea shoreline

NASA Astrophysics Data System (ADS)

Ezersky, M.; Bodet, L.; Al-Zoubi, A.; Camerlynck, C.; Dhemaied, A.; Galibert, P.-Y.; Keydar, S.

2012-04-01

The Dead Sea's coastal areas have been dramatically hit by sinkholes occurrences since around 1990 and there is an obvious potential for further collapse beneath main highways, agricultural lands and other populated places. The sinkhole hazard in this area threatens human lives and compromise future economic developments. The understanding of such phenomenon is consequently of great importance in the development of protective solutions. Several geological and geophysical studies tend to show that evaporite karsts, caused by slow salt dissolution, are linked to the mechanism of sinkhole formation along both Israel and Jordan shorelines. The continuous drop of the Dead Sea level, at a rate of 1m/yr during the past decade, is generally proposed as the main triggering factor. The water table lowering induces the desaturation of shallow sediments overlying buried cavities in 10 to 30 meters thick salt layers, at depths from 25 to 50 meters. Both the timing and location of sinkholes suggest that: (1) the salt weakens as result of increasing fresh water circulation, thus enhancing the karstification process; (2) sinkholes appear to be related to the decompaction of the sediments above karstified zones. The location, depth, thickness and weakening of salt layers along the Dead Sea shorelines, as well as the thickness and mechanical properties of the upper sedimentary deposits, are thus considered as controlling factors of this ongoing process. Pressure-wave seismic methods are typically used to study sinkhole developments in this area. P-wave refraction and reflection methods are very useful to delineate the salt layers and to determine the thickness of overlying sediments. But the knowledge of shear-wave velocities (Vs) should add valuable insights on their mechanical properties, more particularly when the groundwater level plays an important role in the process. However, from a practical point of view, the measurement of Vs remains delicate because of well-known shear waves generation and picking issues in shear-wave refraction seismic methods. As an alternative, indirect estimation of Vs can then be proposed thanks to surface-wave dispersion measurements and inversion, an emerging seismic prospecting method for near-surface engineering and environment applications. Surface-wave prospecting methods have thus been proposed to address the sinkholes development processes along the Dead Sea shorelines. Two approaches have been used: (1) Vs mapping has been performed to discriminate soft and hard zones within salt layers, after calibration of inverted Vs near boreholes. Preliminarily, soft zones, associated with karstified salt, were characterized by Vs values lower than 1000 m/s, whereas hard zones presented values greater than 1400 m/s (will be specified during following studies); (2) roll along acquisition and dispersion stacking has been performed to achieve multi-modal dispersion measurements along linear profiles. Inverted pseudo-2D Vs sections presented low Vs anomalies in the vicinity of existing sinkholes and made it possible to detect loose sediment associated with potential sinkholes occurrences. Acknowledgements This publication was made possible through support provided by the U.S. Agency for International Development (USAID) and MERC Program under terms of Award No M27-050.

Autonomous Realtime Threat-Hunting Robot (ARTHR

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

INL

2008-05-29

Idaho National Laboratory researchers developed an intelligent plug-and-play robot payload that transforms commercial robots into effective first responders for deadly chemical, radiological and explosive threats.

Autonomous Realtime Threat-Hunting Robot (ARTHR

ScienceCinema

INL

2017-12-09

Idaho National Laboratory researchers developed an intelligent plug-and-play robot payload that transforms commercial robots into effective first responders for deadly chemical, radiological and explosive threats.

Rutherford's war

NASA Astrophysics Data System (ADS)

Campbell, John

2016-02-01

Seagulls, sea lions and the comic-book hero Professor Radium were all recruited to fight the threat of submarines during the First World War. But as John Campbell explains, it was Ernest Rutherford who led the way a century ago in using acoustics to deter these deadly craft.

The deceased child in the psychic and social worlds of bereaved parents during the resolution of grief.

PubMed

Klass, D

1997-01-01

A core dynamic by which grief is resolved by parents in Bereaved Parents, a self-help group, is a series of transformations of the inner representation of the dead child in the parent's inner world and in the parent's social world. As the reality of the child's death as well as the reality of the parent's continuing bond with the child are made part of the socially shared reality, the inner representation of the child can be transformed in the parent's psychic life. The end of grief is not severing the bond with the dead child, but integrating the child into the parent's life in a different way than when the child was alive. This article traces the course of the inner representation of the child in the parent's inner life and social world as the parent progresses through Bereaved Parents. It concludes with some comments on the differences that should be maintained between scholarly and popular understandings of phenomena in the continuing bonds survivors maintain with the dead.

Brine Organisms and the Question of Habitat Specific Adaptation

NASA Astrophysics Data System (ADS)

Siegel, B. Z.; Siegel, S. M.; Speitel, Thomas; Waber, Jack; Stoecker, Roy

1984-12-01

Among the well-known ultrasaline terrestrial habitats, the Dead Sea in the Jordan Rift Valley and Don Juan Pond in the Upper Wright Valley represent two of the most extreme. The former is a saturated sodium chloride-magnesium sulfate brine in a hot desert, the latter a saturated calcium chloride brine in an Antarctic desert. Both Dead Sea and Don Juan water bodies themselves are limited in microflora, but the saline Don Juan algal mat and muds contain abundant nutrients and a rich and varied microbiota, including Oscillatoria, Gleocapsa, Chlorella, diatoms, Penicillium and bacteria. In such environments, the existence of an array of specific adaptations is a common, and highly reasonable, presumption, at least with respect to habitat-obligate forms. Nevertheless, many years of ongoing study in our laboratory have demonstrated that lichens (e.g. Cladonia), algae (e.g. Nostoc) and fungi (e.g. Penicillium, Aspergillus) from the humid tropics can sustain metabolism down to -40°C and growth down to -10°C in simulated Dead Sea or Don Juan (or similar) media without benefit of selection or gradual acclimation. Non-selection is suggested in fungi by higher growth rates from vegetative inocula than spores. The importance of nutrient parameters was also evident in responses to potassium and reduced nitrogen compounds. In view of the saline performance of tropical Nostoc, and its presence in the Antarctic dry valley soils, its complete absence in our Don Juan mat samples was and remains a puzzle. We suggest that adaptive capability is already resident in many terrestrial life forms not currently in extreme habitats, a possible reflection of evolutionary selection for wide spectrum environmental adaptability.

BACTERIAL MICROBIOTA IN HARBOR SEALS (PHOCA VITULINA) FROM THE NORTH SEA OF SCHLESWIG-HOLSTEIN, GERMANY, AROUND THE TIME OF MORBILLIVIRUS AND INFLUENZA EPIDEMICS.

PubMed

Siebert, Ursula; Rademaker, Marion; Ulrich, Sophie A; Wohlsein, Peter; Ronnenberg, Katrin; Prenger-Berninghoff, Ellen

2017-04-01

We present microbiologic findings in harbor seal (phoca; Phoca vitulina ) carcasses collected from the North Sea of Schleswig-Holstein, Germany, 1996-2014, and interpret results in relation to potential variations caused by phocine distemper virus and influenza A virus mass mortalities. We conducted microbiologic investigations on 2,124 tissue samples from lung, liver, kidney, spleen, intestine, and mesenteric lymph nodes from 549 dead harbor seals of the German North Sea. A large variety of bacteria, including potentially pathogenic species such as Bordetella bronchiseptica , Brucella spp., Clostridium perfringens , Escherichia coli , Erysipelothrix rhusiopathiae , β-hemolytic streptococci, and Staphylococcus aureus , were isolated. These bacteria were associated with bronchopneumonia, gastroenteritis, hepatitis, polyarthritis, nephritis, myositis, myocarditis, and septicemia. Bordetella bronchiseptica and Streptococcus equi subsp. zooepidemicus were significantly associated with the seal die-offs from phocine distemper in 2002 and influenza in 2014. Many bacteria were detected in tissues of dead harbor seals, of which E. coli , β-hemolytic streptococci, and Brucella spp. might be responsible for pathologic changes. Zoonotic bacteria such as Brucella spp. and E. rhusiopathiae are frequently isolated from harbor seals. Brucella spp. was less and Vibrio spp. more frequently found in summer. Erysipelothrix rhusiopathiae showed an almost regular 4-yr oscillating trend. We found C. perfringens less frequently and E. coli more frequently in harbor seals from St. Peter-Ording. Because zoonotic bacteria are regularly found, handling of dead and live harbor seal specimens should be conducted carefully to prevent transmission to humans. Further investigations are needed to understand microbiota changes in relation to increasing seal populations, reintroduction of rehabilitated seals to the wild, and increasing pressure from anthropogenic activities.

Salt precipitation and dissolution in the late Quaternary Dead Sea: Evidence from chemical and δ37Cl composition of pore fluids and halites

NASA Astrophysics Data System (ADS)

Levy, Elan J.; Yechieli, Yoseph; Gavrieli, Ittai; Lazar, Boaz; Kiro, Yael; Stein, Mordechai; Sivan, Orit

2018-04-01

The chemical composition and δ37Cl of pore fluids from the ICDP core drilled in the deepest floor of the terminal and hypersaline Dead Sea, and halites from the adjacent Mount Sedom salt diapir, are used to establish the dynamics of halite precipitation and dissolution during the last interglacial and glacial periods. Between ∼132 and 116 thousand years ago (ka) halites precipitated in the lake resulting in the expulsion of Na+ and Cl- from the residual solution. Over 50% of the Cl- reservoir was removed, resulting in a decrease in the Na/Cl ratio from 0.57 to 0.19. This process was accompanied by a decrease in δ37Cl values in the precipitating halites and the associated residual Cl- in the lake. The observed decrease fits a Rayleigh distillation curve with a fractionation factor of Δ(NaCl-Dead Sea solution) = +0.32‰ (±0.12) determined in the present study. This behavior implies negligible contribution of external sources of Cl- to the lake during the main peak of the last interglacial, MIS5e. Subsequently, during the last glacial (ca. 117 to 17 ka) dissolution of halite took place, the Na+ and Cl- inventory were replenished, accompanied by an increase in Na/Cl from 0.21 to 0.55 and in the δ37Cl values from -0.46‰ to -0.12‰. While the lake underwent significant dilution during that time, the decrease in salinity was somewhat suppressed by the dissolution of the halite which was mostly derived from Mount Sedom salt diapir.

Enteric bacterial pathogen detection in southern sea otters (Enhydra lutris nereis) is associated with coastal urbanization and freshwater runoff

PubMed Central

Miller, Melissa A.; Byrne, Barbara A.; Jang, Spencer S.; Dodd, Erin M.; Dorfmeier, Elene; Harris, Michael D.; Ames, Jack; Paradies, David; Worcester, Karen; Jessup, David A.; Miller, Woutrina A.

2009-01-01

Although protected for nearly a century, California’s sea otters have been slow to recover, in part due to exposure to fecally-associated protozoal pathogens like Toxoplasma gondii and Sarcocystis neurona. However, potential impacts from exposure to fecal bacteria have not been systematically explored. Using selective media, we examined feces from live and dead sea otters from California for specific enteric bacterial pathogens (Campylobacter, Salmonella, Clostridium perfringens, C. difficile and Escherichia coli O157:H7), and pathogens endemic to the marine environment (Vibrio cholerae, V. parahaemolyticus and Plesiomonas shigelloides). We evaluated statistical associations between detection of these pathogens in otter feces and demographic or environmental risk factors for otter exposure, and found that dead otters were more likely to test positive for C. perfringens, Campylobacter and V. parahaemolyticus than were live otters. Otters from more urbanized coastlines and areas with high freshwater runoff (near outflows of rivers or streams) were more likely to test positive for one or more of these bacterial pathogens. Other risk factors for bacterial detection in otters included male gender and fecal samples collected during the rainy season when surface runoff is maximal. Similar risk factors were reported in prior studies of pathogen exposure for California otters and their invertebrate prey, suggesting that land-sea transfer and/or facilitation of pathogen survival in degraded coastal marine habitat may be impacting sea otter recovery. Because otters and humans share many of the same foods, our findings may also have implications for human health. PMID:19720009

First approximation to congenital malformation rates in embryos and hatchlings of sea turtles.

PubMed

Bárcenas-Ibarra, Annelisse; de la Cueva, Horacio; Rojas-Lleonart, Isaias; Abreu-Grobois, F Alberto; Lozano-Guzmán, Rogelio Iván; Cuevas, Eduardo; García-Gasca, Alejandra

2015-03-01

Congenital malformations in sea turtles have been considered sporadical. Research carried out in the Mexican Pacific revealed high levels of congenital malformations in the olive ridley, but little or no information is available for other species. We present results from analyses of external congenital malformations in olive ridley, green, and hawskbill sea turtles from Mexican rookeries on the Pacific coast and Gulf of Mexico. We examined 150 green and hawksbill nests and 209 olive ridley nests during the 2010 and 2012 nesting seasons, respectively. Olive ridley eggs were transferred to a hatchery and incubated in styrofoam boxes. Nests from the other two species were left in situ. Number of eggs, live and dead hatchlings, and eggs with or without embryonic development were registered. Malformation frequency was evaluated with indices of prevalence and severity. Mortality levels, prevalence and severity were higher in olive ridley than in hawksbill and green sea turtles. Sixty-three types of congenital malformations were observed in embryos, and dead or live hatchlings. Of these, 38 are new reports; 35 for wild sea turtles, three for vertebrates. Thirty-one types were found in hawksbill, 23 in green, and 59 in olive ridley. The head region showed a higher number of malformation types. Malformation levels in the olive ridley were higher than previously reported. Olive ridleys seem more prone to the occurrence of congenital malformations than the other two species. Whether the observed malformation levels are normal or represent a health problem cannot be currently ascertained without long-term assessments. © 2015 Wiley Periodicals, Inc.

Coccidioidomycosis in southern sea otters

USGS Publications Warehouse

Thomas, Nancy J.; Pappagianis, Demosthenes; Creekmore, Lynn H.; Duncan, Ruth M.

1994-01-01

Disseminated coccidioidomycosis was diagnosed postmortem in six southern sea otters (Enhydra lutris nereis) found dying or dead along the Pacific Coast of California at San Luis Obispo County.  These otters were found during winter or summer 1992, 1993, and 1994.  Coccidioides immitis was identified by its morphology in tissue impression smears and by histopathology, and was confirmed by culture.  Positive serologic results were obtained from four of five sea otters tested.  The lungs, pleura, tracheobronchial lymph nodes, liver, and spleen were involved in each case.  There was meningeal involvement in half of the affected animals.  Coccidioidomycosis has been reported in a wild sea otter only once previously, in 1976, and that otter was also found on the coast of San Luis Obispo County.

Overview of studies to determine injury caused by the Exxon Valdez Oil Spill to marine mammals

USGS Publications Warehouse

Loughlin, Thomas R.; Ballachey, Brenda E.; Wright, B.A.; Rice, S.D.; Spies, R.B.; Wolfe, D.A.; Wright, B.A.

1996-01-01

Marine mammal damage assessment studies after the Exxon Valdez oil spill concentrated on sea otters, harbor seals, Steller sea lions, killer whales, and humpback whales. Sea otter and harbor seals were the most affected marine mammal; it was estimated that several thousand otters and several hundred harbor seals died within months of the spill. Steller sea lion, harbor seal, and sea otter numbers were monitored using aerial surveys. Studies of humpback whales and killer whales used photoidentification techniques to determine changes in abundance, distribution, mortality, and natality. Tissues from animals found dead in spill and control areas were analyzed for hydrocarbon levels. Sea otters, sea lions and harbor seals had elevated hydrocarbon levels, but only sea otters and harbor seals showed population declines associated with the spill. Humpback whales were not severely affected by the Exxon Valdez oil spill. Killer whale numbers in the resident AB pod declined after the spill. Coincidental evidence supports the oil spill as the causative agent.

Penetration of the small intestine of a California sea lion (Zalophus californianus) pup by adult hookworms (Uncinaria spp).

PubMed

Spraker, T R; Lyons, E T; DeLong, R L; Zink, R R

2004-03-01

During a study on the mortality of California sea lion (Zalophus californianus) pups born on San Miguel Island, California in 2002, two adult female hookworms (Uncinaria spp) were found penetrating the serosal surface of the intestinal wall and protruding into the peritoneal cavity of one pup. Documentation and a description of this unexpected finding and associated lesions are presented here. Also, adult hookworms were found in the peritoneal fluid of two other dead Z. californianus pups.

The distribution and diversity of sea cucumbers in the coral reefs of the South China Sea, Sulu Sea and Sulawesi Sea

NASA Astrophysics Data System (ADS)

Woo, Sau Pinn; Yasin, Zulfigar; Ismail, Siti Hasmah; Tan, Shau Hwai

2013-11-01

A study on the distribution and diversity of sea cucumbers in the coral reefs of the South China Sea, Sulu Sea and Sulawesi Sea was carried out in July 2009. The survey was done using wandering transect underwater with SCUBA. Twelve species of sea cucumber were found from four different families and nine genera. The most dominant family was Holothuriidae (five species), followed by Stichopodidae (three species), Synaptidae (three species) and Cucumariidae with only one species. The most dominant species found around the island was Pearsonothuria graffei, which can be found abundantly on substrate of dead corals in a wide range of depth (6-15 m). The Sulawesi Sea showed a higher diversity of sea cucumber with seven different species compared to the South China Sea with only six different species and Sulu Sea with only two species. Ordination by multidimensional scaling of Bray-Curtis similarities clustered the sampling locations to three main clusters with two outgroups. Previous studies done indicated a higher diversity of sea cucumber as compared to this study. This can be indication that the population and diversity of sea cucumbers in the reef is under threat.

Marine disease impacts, diagnosis, forecasting, management and policy

USGS Publications Warehouse

Lafferty, Kevin D.; Hofmann, Eileen E.

2016-01-01

As Australians were spending millions of dollars in 2014 to remove the coral-eating crown of thorns sea star from the Great Barrier Reef, sea stars started washing up dead for free along North America's Pacific Coast. Because North American sea stars are important and iconic predators in marine communities, locals and marine scientists alike were alarmed by what proved to be the world's most widespread marine mass mortality in geographical extent and species affected, especially given its mysterious cause. Investigative research using modern diagnostic techniques implicated a never-before-seen virus [1]. The virus inspired international attention to marine diseases, including this theme issue.

Genomic adaptations of the halophilic Dead Sea filamentous fungus Eurotium rubrum.

PubMed

Kis-Papo, Tamar; Weig, Alfons R; Riley, Robert; Peršoh, Derek; Salamov, Asaf; Sun, Hui; Lipzen, Anna; Wasser, Solomon P; Rambold, Gerhard; Grigoriev, Igor V; Nevo, Eviatar

2014-05-09

The Dead Sea is one of the most hypersaline habitats on Earth. The fungus Eurotium rubrum (Eurotiomycetes) is among the few species able to survive there. Here we highlight its adaptive strategies, based on genome analysis and transcriptome profiling. The 26.2 Mb genome of E. rubrum shows, for example, gains in gene families related to stress response and losses with regard to transport processes. Transcriptome analyses under different salt growth conditions revealed, among other things differentially expressed genes encoding ion and metabolite transporters. Our findings suggest that long-term adaptation to salinity requires cellular and metabolic responses that differ from short-term osmotic stress signalling. The transcriptional response indicates that halophilic E. rubrum actively counteracts the salinity stress. Many of its genes encode for proteins with a significantly higher proportion of acidic amino acid residues. This trait is characteristic of the halophilic prokaryotes as well, supporting the theory of convergent evolution under extreme hypersaline stress.

Explosives remain preferred methods for platform abandonment

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

Pulsipher, A.; Daniel, W. IV; Kiesler, J.E.

1996-05-06

Economics and safety concerns indicate that methods involving explosives remain the most practical and cost-effective means for abandoning oil and gas structures in the Gulf of Mexico. A decade has passed since 51 dead sea turtles, many endangered Kemp`s Ridleys, washed ashore on the Texas coast shortly after explosives helped remove several offshore platforms. Although no relationship between the explosions and the dead turtles was ever established, in response to widespread public concern, the US Minerals Management Service (MMS) and National Marine Fisheries Service (NMFS) implemented regulations limiting the size and timing of explosive charges. Also, more importantly, they requiredmore » that operators pay for observers to survey waters surrounding platforms scheduled for removal for 48 hr before any detonations. If observers spot sea turtles or marine mammals within the danger zone, the platform abandonment is delayed until the turtles leave or are removed. However, concern about the effects of explosives on marine life remains.« less

Influence of fluctuations of historic water bodies on fault stability and earthquake recurrence interval: The Dead Sea Rift as a case study

NASA Astrophysics Data System (ADS)

Belferman, Mariana; Katsman, Regina; Agnon, Amotz; Ben-Avraham, Zvi

2017-04-01

Despite the global, social and scientific impact of earthquakes, their triggering mechanisms remain often poorly defined. We suggest that dynamic changes in the levels of the historic water bodies occupying tectonic depressions at the Dead Sea Rift cause significant variations in the shallow crustal stress field and affect local fault systems in a way that may promote or suppress earthquakes. This mechanism and its spatial and temporal scales differ from those in tectonically-driven deformations. We use analytical and numerical poroelastic models to simulate immediate and delayed seismic responses resulting from the observed historic water level changes. The role of variability in the poroelastic and the elastic properties of the rocks composing the upper crust in inducing or retarding deformations under a strike-slip faulting regime is studied. The solution allows estimating a possible reduction in a seismic recurrence interval. Considering the historic water level fluctuation, our preliminary simulations show a promising agreement with paleo-seismic rates identified in the field.

Live and dead deep-sea benthic foraminiferal macrofauna of the Levantine basin (SE Mediterranean) and their ecological characteristics

NASA Astrophysics Data System (ADS)

Hyams-Kaphzan, Orit; Lubinevsky, Hadas; Crouvi, Onn; Harlavan, Yehudit; Herut, Barak; Kanari, Mor; Tom, Moshe; Almogi-Labin, Ahuva

2018-06-01

The present study sought to quantitatively characterize the live and dead benthic foraminifera communities of the deep southeastern Levantine basin of the Mediterranean Sea (33.4º-31.7 ºN, 31.3º-34.9 ºE; 100-1900 m water depth) and their relationships to environmental conditions. Box corer samples were collected at 50 sites between June and July 2013. The foraminiferal macrofauna (> 250 μm) were enumerated and identified (76% to the species level). Six live foraminiferal assemblages were identified, inhabiting six biotopes, the shelf margin (SM), two upper continental slopes (UCS1 and UCS2), the lower continental slope (LCS), the eastern bathyal plain (EBP) and the western bathyal plain (WBP). The dead communities were divided into four biotopes, generally compatible with the live ones, excluding the UCS2 and the EBP. The foraminiferal density in the various live biotopes was relatively stable across the studied area, excluding the UCS2 and EBP, unlike the density of the dead shells, which increased with depth. The number of taxa per biotope was estimated by rarefaction curves and compared to the observed numbers, with a decreasing number of live taxa with water depth. The alpha-diversity, which was evaluated in relation to the number of sampled individuals, reached an asymptote in all biotopes, with very low values in the WBP. The within-biotope heterogeneity was evaluated by the average Chao-Sørensen similarity index and by a beta-diversity index (exp(gamma diversity) - exp(alpha diversity)), revealing variable heterogeneities in both assemblages. Water depth, sediment grain size mode, CaCO3 (wt%), and clay fraction (wt%) were jointly but feebly correlated with live faunal composition.

Seasonal prevalence and intensity of hookworms (Uncinaria spp.) in California sea lion (Zalophus californianus) pups born in 2002 on San Miguel Island, California.

PubMed

Lyons, E T; Delong, R L; Spraker, T R; Melin, S R; Laake, J L; Tolliver, S C

2005-05-01

Intestines of California sea lion (Zalophus californianus) pups (n= 204), born in 2002 on San Miguel Island, California, were examined for hookworms (Uncinaria spp.) as part of a seasonal mortality study from June through December 2002 and January 2003. The investigation was planned to coincide with most of the previously established hookworm infection period of the pups. Prevalence of hookworms in dead pups was 100% for each month of the study. The geometric mean intensity of infections per month was: 94.03 (n=30) for June, 629.09 (n=50) for July, 319.90 (n=31) for August, 159.90 (n=30) for October, 109.03 (n=30) for November, 37.84 (n=24) for December 2002 and 11.05 (n=9) for January 2003. In addition to the temporal pattern, the infection intensity was higher for pups in good condition and for male pups. An inter-year comparison of hookworm counts from dead pups collected in July of 1996, 2000, and 2002 also demonstrated higher intensity in pups in better condition but sex-differences in intensity were inconsistent across years. The inter-year comparison also demonstrated higher intensities in dead pups collected from portions of the rookery with sandy substrate versus rocky substrate. No annual differences in intensity were found after adjusting for substrate and condition.

Autonomous Realtime Threat-Hunting Robot (ARTHR)

ScienceCinema

Idaho National Laboratory - David Bruemmer, Curtis Nielsen

2017-12-09

Idaho National Laboratory researchers developed an intelligent plug-and-play robot payload that transforms commercial robots into effective first responders for deadly chemical, radiological and explosive threats. To learn more, visit

[A case of lycanthropy with deadly violence].

PubMed

Bénézech, M; De Witte, J; Etchepare, J J; Bourgeois, M

1989-01-01

After a short historical review of the contemporary medical literature, the authors analyze a new and original observation of lycanthropy. He is a 28 years old man, imprisoned for deadly violence, who has been showing, for many years, the belief of being transformed into a werewolf during depersonalization episodes when he presents a lycanthropic behaviour. Our observation is closer to hysteria and mythomania on an antisocial personality, although it seems difficult to place the mental pathology of this alcoholic recidivist delinquent into a nosographical frame.

Hydroclimatic variability in the Levant during the early last glacial (∼ 117-75 ka) derived from micro-facies analyses of deep Dead Sea sediments

NASA Astrophysics Data System (ADS)

Neugebauer, I.; Schwab, M. J.; Waldmann, N. D.; Tjallingii, R.; Frank, U.; Hadzhiivanova, E.; Naumann, R.; Taha, N.; Agnon, A.; Enzel, Y.; Brauer, A.

2015-08-01

The new sediment record from the deep Dead Sea basin (ICDP core 5017-1) provides a unique archive for hydroclimatic variability in the Levant. Here, we present high-resolution sediment facies analysis and elemental composition by μXRF scanning of core 5017-1 to trace lake levels and responses of the regional hydroclimatology during the time interval from ca 117-75 ka, i.e. the transition between the last interglacial and the onset of the last glaciation. We distinguished six major micro-facies types and interpreted these and their alterations in the core in terms of relative lake level changes. The two end-member facies for highest and lowest lake levels are (a) up to several meters thick, greenish sediments of alternating aragonite and detrital marl laminae (aad) and (b) thick halite facies, respectively. Intermediate lake levels are characterised by detrital marls with varying amounts of aragonite, gypsum or halite, reflecting lower-amplitude, shorter-term variability. Two intervals of pronounced lake level drops occurred at ∼110-108 ± 5 and ∼93-87 ± 7 ka. They likely coincide with stadial conditions in the central Mediterranean (Melisey I and II pollen zones in Monticchio) and low global sea levels during MIS 5d and 5b. However, our data do not support the current hypothesis of an almost complete desiccation of the Dead Sea during the earlier of these lake level low stands based on a recovered gravel layer. Based on new petrographic analyses, we propose that, although it was a low stand, this well-sorted gravel layer may be a vestige of a thick turbidite that has been washed out during drilling rather than an in-situ beach deposit. Two intervals of higher lake stands at ∼108-93 ± 6 and ∼87-75 ± 7 ka correspond to interstadial conditions in the central Mediterranean, i.e. pollen zones St. Germain I and II in Monticchio, and GI 24 + 23 and 21 in Greenland, as well as to sapropels S4 and S3 in the Mediterranean Sea. These apparent correlations suggest a close link of the climate in the Levant to North Atlantic and Mediterranean climates during the time of the build-up of Northern Hemisphere ice shields in the early last glacial period.

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2013 CFR

2013-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2012 CFR

2012-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2014 CFR

2014-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2010 CFR

2010-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

36 CFR 7.73 - Buck Island Reef National Monument.

Code of Federal Regulations, 2011 CFR

2011-07-01

...), seashells, corals, dead coral, sea fans, sponges and all associated reef invertebrates, plants, fruits and... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Buck Island Reef National... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.73 Buck Island Reef National Monument...

Large Aquatic Ecosystem Restoration Monitoring for Decision Makers: Monitoring to Target and Evaluate Success of Ecosystem Restoration

EPA Science Inventory

Monitoring ecosystem restoration at various scales in LAEs can be challenging, frustrating and rewarding. Some of the major ecosystem restoration monitoring occurring in LAEs include: seagrass expansion/contraction; dead zone sizes; oyster reefs; sea turtle nesting; toxic and nu...

Chemical Case Studies: Science-Society "Bonding."

ERIC Educational Resources Information Center

Hofstein, Avi; Nae, Nehemia

1981-01-01

Describes a unit designed to illustrate the "science-society-technology connection," in which three case studies of the chemical industry in Israel are presented to high school chemistry students. Chosen for the unit are case studies on copper production in Timna, on plastics, and on life from the Dead Sea. (CS)

SELENIHALANAEROBACTER SHRIFTII GEN. NOV., SP. NOV., A HALOPHILIC ANAEROBE FROM DEAD SEA SEDIMENTS THAT RESPIRES SELENATE. (R826105)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

50 CFR 230.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... direction of any person described in paragraph (1) of this definition. Calf means any whale less than 1 year... cooperative management of aboriginal subsistence whaling operations. Landing means bringing a whale or any.... Stinker means a dead, unclaimed whale found upon a beach, stranded in shallow water, or floating at sea...

50 CFR 230.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... direction of any person described in paragraph (1) of this definition. Calf means any whale less than 1 year... cooperative management of aboriginal subsistence whaling operations. Landing means bringing a whale or any.... Stinker means a dead, unclaimed whale found upon a beach, stranded in shallow water, or floating at sea...

50 CFR 230.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... direction of any person described in paragraph (1) of this definition. Calf means any whale less than 1 year... cooperative management of aboriginal subsistence whaling operations. Landing means bringing a whale or any.... Stinker means a dead, unclaimed whale found upon a beach, stranded in shallow water, or floating at sea...

50 CFR 230.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... direction of any person described in paragraph (1) of this definition. Calf means any whale less than 1 year... cooperative management of aboriginal subsistence whaling operations. Landing means bringing a whale or any.... Stinker means a dead, unclaimed whale found upon a beach, stranded in shallow water, or floating at sea...

Life history of the deep-sea cephalopod family Histioteuthidae in the western Mediterranean

NASA Astrophysics Data System (ADS)

Quetglas, Antoni; de Mesa, Aina; Ordines, Francesc; Grau, Amàlia

2010-08-01

The life cycle of the two species of the deep-sea family Histioteuthidae inhabiting the Mediterranean Sea ( Histioteuthis reversa and Histioteuthis bonnellii) was studied from monthly samples taken throughout the year during daytime hours by bottom trawl gears. A small sample of individuals found floating dead on the sea surface was also analyzed. Both species were caught exclusively on the upper slope at depths greater than 300 m. Their frequency of occurrence increased with depth and showed two different peaks, at 500-600 m and 600-700 m depth in H. bonnellii and H. reversa, respectively, which might indicate spatial segregation. Maturity stages were assigned using macroscopic determination and confirmed with histological analyses. Although mature males were caught all year round, no mature females were found, which suggests that their sexual maturation in the western Mediterranean takes place deeper than the maximum depth sampled (800 m). In fact, the increase in mean squid size with increasing depth in H. reversa indicates an ontogenetic migration to deeper waters. The individuals of both species found floating dead on the sea surface were spent females which had a relatively large cluster of small atresic eggs and a small number of remaining mature eggs scattered in the ovary and mantle cavity. The sizes of these females were clearly larger than the largest individuals caught with bottom trawls. A total of 12 and 7 different types of prey, belonging to three major taxonomic groups (crustaceans, osteichthyes and cephalopods), were identified in the stomach contents of H. reversa and H. bonnellii, respectively. In both species fishes were by far the main prey followed by crustaceans, whereas cephalopods were found only occasionally. The preys identified, mainly myctophids and natantian crustaceans, indicate that both histioteuthids base their diet on pelagic nictemeral migrators.

Tumors in sea turtles: The insidious menace of fibropapillomatosis

USGS Publications Warehouse

Work, Thierry M.; Balazs, George H.

2013-01-01

Early in July 2013, a colleague in New Caledonia reported the stranding of a green sea turtle on the far northwest of the island. The animal had washed up dead on a rocky beach with multiple large tumors on its neck and hind flippers. To all appearances, the turtle had fibropapillomatosis (FP), a tumor disease affecting marine turtles globally. This was the first known case of FP on the island—an alarming find, and another example of the creeping expansion of this disease in green turtles around the world.

A Joint Sea Beam/SeaMARC II Survey of the East Pacific Rise and Its Flanks 7 deg 50 min-10 deg 30 min N, to Establish a Geologic Acoustic Natural Laboratory

DTIC Science & Technology

1991-01-15

of Oceanography, University of Rhode Island , Narragansett, R.I. 02882, A. Shor and C. Nishimura, Hawaii Institute of Geophysics, University of Hawaii...across the Clipperton and the absence of intra-transform spreading, and opening across the Siqueiros with sustained intra-transform spreading. An...Ma. Future work will focus on the significant task of combining this survey with three 1987 SeaMARC II surveys of the Clipperton transform, the 9°N

The Sea around Us: Social Climbing in "Seabiscuit," "Whale Rider," and "Finding Nemo"

ERIC Educational Resources Information Center

Beck, Bernard

2004-01-01

All life begins in the sea, people are taught, and a great transformation extends it to new places on land. The sea has always echoed this transformation in images of human aspiration in myths and metaphors. In the summer of 2003, this powerful image appeared again in the movies. In three very different films, "Seabiscuit," "Whale Rider," and…

INTERIOR OF NORTH ENTRY VESTIBULE, SHOWING TRANSFORMER ROOM BEHIND WIRE ...

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

INTERIOR OF NORTH ENTRY VESTIBULE, SHOWING TRANSFORMER ROOM BEHIND WIRE MESH, VIEW FACING EAST-SOUTHEAST. - Naval Air Station Barbers Point, Telephone Exchange, Coral Sea Road north of Bismarck Sea Road, Ewa, Honolulu County, HI

Rapid Assessment of Seismic Vulnerability in Palestinian Refugee Camps

NASA Astrophysics Data System (ADS)

Al-Dabbeek, Jalal N.; El-Kelani, Radwan J.

Studies of historical and recorded earthquakes in Palestine demonstrate that damaging earthquakes are occurring frequently along the Dead Sea Transform: Earthquake of 11 July 1927 (ML 6.2), Earthquake of 11 February 2004 (ML 5.2). In order to reduce seismic vulnerability of buildings, losses in lives, properties and infrastructures, an attempt was made to estimate the percentage of damage degrees and losses at selected refugee camps: Al Ama`ri, Balata and Dhaishe. Assessing the vulnerability classes of building structures was carried out according to the European Macro-Seismic Scale 1998 (EMS-98) and the Fedral Emergency Management Agency (FEMA). The rapid assessment results showed that very heavy structural and non structural damages will occur in the common buildings of the investigated Refugee Camps (many buildings will suffer from damages grades 4 and 5). Bad quality of buildings in terms of design and construction, lack of uniformity, absence of spaces between the building and the limited width of roads will definitely increase the seismic vulnerability under the influence of moderate-strong (M 6-7) earthquakes in the future.

Late Holocene activity of the Dead Sea Transform revealed in 3D palaeoseismic trenches on the Jordan Gorge segment [rapid communication

NASA Astrophysics Data System (ADS)

Marco, Shmuel; Rockwell, Thomas K.; Heimann, Ariel; Frieslander, Uri; Agnon, Amotz

2005-05-01

Three-dimensional excavations of buried stream channels that have been displaced by the Jordan Fault, the primary strand of the Dead Sea fault zone in northern Israel, demonstrate that late Holocene slip has been primarily strike-slip at a minimum rate of 3 mm/yr. The palaeoseismic study was carried out in the Bet-Zayda Valley, the delta of the Jordan River at the north shore of the Sea of Galilee. The site was chosen where a north-striking scarp with up to 1-m vertical expression crosses the flat valley. One group of trench excavations was located where a small stream crosses the scarp. The active stream, which is incised into the scarp, is not offset by the fault. However we found two palaeo channels about 2 m below the surface offset sinistrally 2.7±0.2 m by the fault and two younger nested channels offset 0.5±0.05 m. Based on radiocarbon dates we attribute the last 0.5 m rupture to the earthquake of October 30, 1759. The older offset of 2.2 m most probably occurred in the earthquakes of May 20, 1202. These two events correlate with the findings at Ateret, about 12 km north of Bet-Zayda, where the 1202 earthquake produced 1.6 m of lateral displacement in E-W-striking defence walls of a Crusader castle, and an Ottoman mosque was offset 0.5 m in the earthquake of 1759. In the second group of trenches some 60 m farther south we found another offset channel. Its northern margin is displaced 15 m sinistrally whereas the southern margin shows only 9 m of sinistral offset. The dip slip component is 1.2 m, west side down. The different amounts of margin offset can be explained by erosion of the southern margin during the first 6 m of displacement. Additional slip of 9 m accrued after the stream had been abandoned and buried by a 2-m-thick lacustrine clay layers. Radiocarbon dates on organic residue provide the age control which indicates that the 15 m of slip has accrued over the past 5 kyr, yielding a short-term slip rate of 3 mm/yr for the late Holocene. It is possible that our study covers only part of the fault zone, hence we regard this mean slip rate to be a minimum for the DST. Based on other palaeoseismic studies the best estimate for Quaternary slip rate is 4±1 mm/yr.

Aged keratinocyte phenotyping: morphology, biochemical markers and effects of Dead Sea minerals.

PubMed

Soroka, Yoram; Ma'or, Zeev; Leshem, Yael; Verochovsky, Lilian; Neuman, Rami; Brégégère, François Menahem; Milner, Yoram

2008-10-01

The aging process and its characterization in keratinocytes have not been studied in depth until now. We have assessed the cellular and molecular characteristics of aged epidermal keratinocytes in monolayer cultures and in skin by measuring their morphological, fluorometric and biochemical properties. Light and electron microscopy, as well as flow cytometry, revealed increase in cell size, changes in cell shape, alterations in mitochondrial structure and cytoplasmic content with aging. We showed that the expression of 16 biochemical markers was altered in aged cultured cells and in tissues, including caspases 1 and 3 and beta-galactosidase activities, immunoreactivities of p16, Ki67, 20S proteasome and effectors of the Fas-dependent apoptotic pathway. Aged cells diversity, and individual variability of aging markers, call for a multifunctional assessment of the aging phenomenon, and of its modulation by drugs. As a test case, we have measured the effects of Dead Sea minerals on keratinocyte cultures and human skin, and found that they stimulate proliferation and mitochondrial activity, decrease the expression of some aging markers, and limit apoptotic damage after UVB irradiation.

Fire and Brimstone: The Microbially Mediated Formation of Elemental Sulfur Nodules from an Isotope and Major Element Study in the Paleo-Dead Sea

PubMed Central

Bishop, Tom; Turchyn, Alexandra V.; Sivan, Orit

2013-01-01

We present coupled sulfur and oxygen isotope data from sulfur nodules and surrounding gypsum, as well as iron and manganese concentration data, from the Lisan Formation near the Dead Sea (Israel). The sulfur isotope composition in the nodules ranges between -9 and -11‰, 27 to 29‰ lighter than the surrounding gypsum, while the oxygen isotope composition of the gypsum is constant around 24‰. The constant sulfur isotope composition of the nodule is consistent with formation in an ‘open system’. Iron concentrations in the gypsum increase toward the nodule, while manganese concentrations decrease, suggesting a redox boundary at the nodule-gypsum interface during aqueous phase diagenesis. We propose that sulfur nodules in the Lisan Formation are generated through bacterial sulfate reduction, which terminates at elemental sulfur. We speculate that the sulfate-saturated pore fluids, coupled with the low availability of an electron donor, terminates the trithionate pathway before the final two-electron reduction, producing thionites, which then disproportionate to form abundant elemental sulfur. PMID:24098403

Rheology of Dead Sea shampoo containing the antidandruff climbazole.

PubMed

Abu-Jdayil, B; Mohameed, H A

2004-12-01

In this study, the effect of the antidandruff climbazole on the rheology of hair shampoo containing Dead Sea (DS) salt was investigated. The presence of either DS salt or the climbazole led to increase in the shampoo viscosity. An optimum concentration was found where the viscosity of shampoo was maximum. In the absence of DS salt, the viscosity of hair shampoo increased with increasing the climbazole concentration to reach a maximum value at 1.0 wt%. Further addition of climbazole decreased the viscosity of shampoo. Adjusting the pH of the shampoo at 5.5 and 5.0 shifted the optimum climbazole concentration (corresponds to maximum viscosity) to 0.8 wt% and led to increase in the viscosity of shampoo. On the other hand, the addition of climbazole to the shampoo containing DS salt resulted in a decrease in shampoo viscosity. This decrease of shampoo viscosity became more pronounced with increasing the climbazole and/or DS salt concentrations. By controlling the pH of shampoo, an optimum formula of shampoo comprising both climbazole and DS salt and having maximum viscosity was obtained.

Unravelling environmental conditions during the Holocene in the Dead Sea region using multiple archives

NASA Astrophysics Data System (ADS)

Rambeau, Claire; van Leeuwen, Jacqueline; van der Knaap, Pim; Gobet, Erika

2016-04-01

For the most arid parts of the Southern Levant (roughly corresponding to modern Jordan, Israel and Palestine), environmental reconstructions are impeded by the limited number of archives, and the frequent contradictions between individual palaeoenvironmental records. The Southern Levant is characterised by steep climate gradients; local conditions presently range from arid to dry Mediterranean, with limits that may have fluctuated during the Holocene. This further complicates the determination of site-specific past environmental conditions. Understanding past climate and environmental evolution through time, at a local level, is however crucial to compare these with societal evolution during the Holocene, which features major cultural developments such as cereal cultivation, animal domestication, water management, as well as times of preferential settlement growth or site abandonment. This contribution proposes to examine the different archives available for the Dead Sea region, paying special attention to the most recent pollen data obtained from the area. It will particularly critically compare local to regional-scale information, and try to decipher the main evolutions of environmental conditions during the Holocene in arid and semi-arid Southern Levant.

GEMINI-TITAN (GT)-11 - EARTH SKY - OVERLAY - SINAI PENINSULA - POINTS OF INTEREST - OUTER SPACE

NASA Image and Video Library

1966-09-14

S66-54893 (14 Sept. 1966) --- Near East area as seen from the orbiting Gemini-11 spacecraft during its 26th revolution of Earth. The United Arab Republic (Egypt) is in foreground. Triangular-shaped area is the Sinai Peninsula. Saudi Arabia is at upper right. The Mediterranean Sea is at upper left. The Gulf of Suez separates Egypt from the Sinai Peninsula. The Red Sea is at bottom right. The Gulf of Aqaba is the body of water in right center of photograph separating the Sinai Peninsula and the Arabian Peninsula. The Dead Sea, Sea of Galilee, Jordan and Israel are in top center of picture. Iraq is at top right edge of photograph. Taken with a J. A. Maurer 70mm camera, using Eastman Kodak, Ektachrome, MS (S.O. 368) color film. Photo credit: NASA

Seismicity of the Earth 1900–2010 Middle East and vicinity

USGS Publications Warehouse

Jenkins, Jennifer; Turner, Bethan; Turner, Rebecca; Hayes, Gavin P.; Davies, Sian; Dart, Richard L.; Tarr, Arthur C.; Villaseñor, Antonio; Benz, Harley M.

2013-01-01

No fewer than four major tectonic plates (Arabia, Eurasia, India, and Africa) and one smaller tectonic block (Anatolia) are responsible for seismicity and tectonics in the Middle East and surrounding region. Geologic development of the region is a consequence of a number of first-order plate tectonic processes that include subduction, large-scale transform faulting, compressional mountain building, and crustal extension. In the east, tectonics are dominated by the collision of the India plate with Eurasia, driving the uplift of the Himalaya, Karakorum, Pamir and Hindu Kush mountain ranges. Beneath the Pamir‒Hindu Kush Mountains of northern Afghanistan, earthquakes occur to depths as great as 200 km as a result of remnant lithospheric subduction. Along the western margin of the India plate, relative motions between India and Eurasia are accommodated by strike-slip, reverse, and oblique-slip faulting, resulting in the complex Sulaiman Range fold and thrust belt, and the major translational Chaman Fault in Afghanistan. Off the south coasts of Pakistan and Iran, the Makran trench is the surface expression of active subduction of the Arabia plate beneath Eurasia. Northwest of this subduction zone, collision between the two plates forms the approximately 1,500-km-long fold and thrust belts of the Zagros Mountains, which cross the whole of western Iran and extend into northeastern Iraq. Tectonics in the eastern Mediterranean region are dominated by complex interactions between the Africa, Arabia, and Eurasia plates, and the Anatolia block. Dominant structures in this region include: the Red Sea Rift, the spreading center between the Africa and Arabia plates; the Dead Sea Transform, a major strike-slip fault, also accommodating Africa-Arabia relative motions; the North Anatolia Fault, a right-lateral strike-slip structure in northern Turkey accommodating much of the translational motion of the Anatolia block westwards with respect to Eurasia and Africa; and the Cyprian Arc, a convergent boundary between the Africa plate to the south, and Anatolia Block to the north.

Colloid transport in porous media: impact of hyper-saline solutions.

PubMed

Magal, Einat; Weisbrod, Noam; Yechieli, Yoseph; Walker, Sharon L; Yakirevich, Alexander

2011-05-01

The transport of colloids suspended in natural saline solutions with a wide range of ionic strengths, up to that of Dead Sea brines (10(0.9) M) was explored. Migration of microspheres through saturated sand columns of different sizes was studied in laboratory experiments and simulated with mathematical models. Colloid transport was found to be related to the solution salinity as expected. The relative concentration of colloids at the columns outlet decreased (after 2-3 pore volumes) as the solution ionic strength increased until a critical value was reached (ionic strength > 10(-1.8) M) and then remained constant above this level of salinity. The colloids were found to be mobile even in the extremely saline brines of the Dead Sea. At such high ionic strength no energetic barrier to colloid attachment was presumed to exist and colloid deposition was expected to be a favorable process. However, even at these salinity levels, colloid attachment was not complete and the transport of ∼ 30% of the colloids through the 30-cm long columns was detected. To further explore the deposition of colloids on sand surfaces in Dead Sea brines, transport was studied using 7-cm long columns through which hundreds of pore volumes were introduced. The resulting breakthrough curves exhibited a bimodal shape whereby the relative concentration (C/C(0)) of colloids at the outlet rose to a value of 0.8, and it remained relatively constant (for the ∼ 18 pore volumes during which the colloid suspension was flushed through the column) and then the relative concentration increased to a value of one. The bimodal nature of the breakthrough suggests different rates of colloid attachment. Colloid transport processes were successfully modeled using the limited entrapment model, which assumes that the colloid attachment rate is dependent on the concentration of the attached colloids. Application of this model provided confirmation of the colloid aggregation and their accelerated attachment during transport through soil in high salinity solution. Copyright © 2011 Elsevier Ltd. All rights reserved.

Using natural laboratories and modeling to decipher lithospheric rheology

NASA Astrophysics Data System (ADS)

Sobolev, Stephan

2013-04-01

Rheology is obviously important for geodynamic modeling but at the same time rheological parameters appear to be least constrained. Laboratory experiments give rather large ranges of rheological parameters and their scaling to nature is not entirely clear. Therefore finding rheological proxies in nature is very important. One way to do that is finding appropriate values of rheological parameter by fitting models to the lithospheric structure in the highly deformed regions where lithospheric structure and geologic evolution is well constrained. Here I will present two examples of such studies at plate boundaries. One case is the Dead Sea Transform (DST) that comprises a boundary between African and Arabian plates. During the last 15- 20 Myr more than 100 km of left lateral transform displacement has been accumulated on the DST and about 10 km thick Dead Sea Basin (DSB) was formed in the central part of the DST. Lithospheric structure and geological evolution of DST and DSB is rather well constrained by a number of interdisciplinary projects including DESERT and DESIRE projects leaded by the GFZ Potsdam. Detailed observations reveal apparently contradictory picture. From one hand widespread igneous activity, especially in the last 5 Myr, thin (60-80 km) lithosphere constrained from seismic data and absence of seismicity below the Moho, seem to be quite natural for this tectonically active plate boundary. However, surface heat flow of less than 50-60mW/m2 and deep seismicity in the lower crust ( deeper than 20 km) reported for this region are apparently inconsistent with the tectonic settings specific for an active continental plate boundary and with the crustal structure of the DSB. To address these inconsistencies which comprise what I call the "DST heat-flow paradox", a 3D numerical thermo-mechanical model was developed operating with non-linear elasto-visco-plastic rheology of the lithosphere. Results of the numerical experiments show that the entire set of observations for the DSB can be explained within the classical pull-apart model assuming that (1) the lithosphere has been thermally eroded at about 20 Ma, just before the active faulting at the DST, and (2) the uppermost mantle in the region have relatively weak rheology consistent with the experimental data for wet olivine or pyroxenite. Another example is modeling of the collision of India and Eurasia in Tibet. Our recent thermo-mechanical model (see abstract by Tympel et al) reproduce well many important features of this orogeny, including observed convergence and distance of underthrusting of Indian lithosphere beneath Tibet, if long-term friction at India-Eurasia interface is about 0.04- 0.05, which is typical for oceanic subduction zones, but is unexpected low for continental setting.

Vegetation and climate of the southern Levant during the last Interglacial

NASA Astrophysics Data System (ADS)

Chen, Chunzhu; Litt, Thomas

2015-04-01

Sediments in the Dead Sea basin are outstanding archives for understanding the paleoenvironment of the southern Levant because of their locations at the boundary between the Mediterranean and Arabian-Sahara climate zones. During the past decades, extensive investigations have demonstrated high lake levels during the last Glacial but low lake levels during the present and last Interglacial. However, palynological results from Lake Kinneret and Birkat Ram suggested a dry last Glacial and wet Holocene (Schiebel, 2013; Chen and Miebach, unpublished). Studies on Lake Samra (last interglacial precursor of the modern Dead Sea) became a focus after deep drilling cores were retrieved in 2011. Core 5017-1A encompasses the most complete Samra profile in the region, which exhibits thick halite layers indicating extremely low lake levels (Neugebauer et al., 2014). As interpreted based on lithological and hydrological results, the marine isotope stage (MIS) 5e was the most arid period (work in progress). In this case, pollen analysis would provide independent evidence of the regional climate changes. Our preliminary result shows that late MIS 6 was characterized by an expansion of goosefoot (Chenopodiaceae)-dominated desert/semi-desert. During the MIS 6/5 transition, an abrupt increase of grasses and a corresponding decline of goosefoot suggest the occurrence of a more humid grass steppe, whereas the woodlands were still open. The MIS 5e has witnessed higher woodland density and moisture availability provided high values of Mediterranean woodland components (mainly olives and deciduous oaks). From MIS 5d to 5a, a drying trend was recorded from the contraction of the Mediterranean biome and the expansion of steppe/semi-steppe. As a key time interval of our study, MIS 5e comprised a typical vegetation succession process that is also prevalent in other Mediterranean pollen records. Therefore, in biostratigraphical terms, high abundances of woody taxa marks the MIS 5e, although the timing and moisture pattern contradict those implied by non-pollen proxies. This study presents the first consecutive last Interglacial pollen record in the southern Levant and will contribute to researches of modern human dispersal. Further quantitative reconstructions will be carried out on the basis of the Holocene counterpart (Litt et al., 2012). Reference: Litt, T., et al., 2012. Holocene climate variability in the Levant from the Dead Sea pollen record. Quaternary Science Reviews 49, 95-105. Neugebauer, I., et al., 2014. Lithology of the long sediment record recovered by the ICDP Dead Sea Deep Drilling Project (DSDDP). Quaternary Science Reviews 102, 149-165. Schiebel, V., 2013. Vegetation and climate history of the southern levant during the last 30,000 years based on palynological investigation. Bonn, University of Bonn, Dissertation, 2013.

Possible connection between large volcanic eruptions and level rise episodes in the Dead Sea Basin

NASA Astrophysics Data System (ADS)

Bookman, Revital; Filin, Sagi; Avni, Yoav; Rosenfeld, Daniel; Marco, Shmuel

2014-05-01

The June 1991 Pinatubo volcanic eruption perturbed the atmosphere, triggering short-term worldwide changes in surface and lower troposphere temperatures, precipitation, and runoff. The following winter was anomalously wet in the Levant, with a ~2-meter increase in the Dead Sea level that created a distinct morphological terrace along the lake's shore. Given the global radiative and chemical effects of volcanogenic aerosols on climatic systems, we tested the hypothesis that the 1991-92 winter shore terrace is a modern analogue to the linkage between past volcanic eruptions and a sequence of shore terraces on the cliffs around the Dead Sea Basin. Analysis of historical annual precipitation series from Jerusalem showed a significant positive correlation between the Dust Veil Index (DVI) of the modern largest eruptions and corresponding annual rainfall. The DVI was found to explain nearly 50% of the variability in the annual rainfall, such that greater DVI means more rainfall. Other factors that may affect the annual rainfall in the region as the Southern Oscillation Index (SOI) and the North Atlantic oscillations (NAO) were incorporated along with the DVI in a linear multiple regression model. It was found that the NAO did not contribute anything except for increased noise, but the added SOI increased the explained variability of rainfall to more than 60%. The atmospheric effect of the volcanic aerosol cloud produced after the Mt. Pinatubo eruption shows responses in the climate system on a hemispherical to global scale. Volcanic eruptions with a VEI of 6, as in the Pinatubo, occurred about once a century during the Holocene period at a rate that persisted throughout the last glacial-interglacial cycle, though with large variations in the mean. This occurrence is similar to the frequency of shore terrace build-up during the Lake Lisan desiccation. Sixteen shore terraces, detected using airborne laser scanning data, were interpreted as indicating short-term level rises due to episodes of enhanced precipitation and runoff during the dramatic drop in Lake Lisan's (palaeo-Dead Sea) level at the end of the Last Glacial Maximum. The terraces were compared with a dated time series of volcanogenic sulfate from the GISP2 ice core, and similar numbers of sulfate concentration peaks and shore terraces were found. Furthermore, a significant correlation was found between SO4 concentration peaks and the heights of the terraces. This correlation may indicate a link between the explosivity of past eruptions, the magnitude of stratospheric injection, and their impact on the northern hemisphere water balance. The record of such short-term climato-hydrological effects is made possible by the dramatic desiccation of Lake Lisan. Detailed records of such events, albeit rare because of their vulnerability and short longevity, provide an important demonstration of global climatic teleconnections.

Transformation of the genital epithelial tract occurs early in California sea lion development

PubMed Central

Barragán-Vargas, Cecilia; Montano-Frías, Jorge; Ávila Rosales, Germán; Godínez-Reyes, Carlos R.; Acevedo-Whitehouse, Karina

2016-01-01

An unusually high prevalence of metastatic urogenital carcinoma has been observed in free-ranging California sea lions stranded off the coast of California in the past two decades. No cases have been reported for sea lions in the relatively unpolluted Gulf of California. We investigated occurrence of genital epithelial transformation in 60 sea lions (n=57 pups and 3 adult females) from the Gulf of California and examined whether infection by a viral pathogen previously found to be associated with urogenital carcinoma accounted for such alterations. We also explored the contribution of MHC class II gene expression on transformation. Cellular alterations, such as squamous cell atypia (ASC), atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions were observed in 42% of the pups and in 67% of the adult females. Normal genital epithelium was more common in male than female pups. ASC was five times more likely to occur in older pups. Epithelial alterations were unrelated to infection by the potentially oncogenic otarine type I gammaherpesvirus (OtHV-1), but ASCUS was more common in pups with marked and severe inflammation. Expression of MHC class II DRB loci (Zaca DRB-D) by peripheral antigen-presenting leucocytes showed a slightly ‘protective’ effect for ASC. We propose that transformation of the California sea lion genital epithelium is relatively common in young animals, increases with age and is probably the result of infection by an unidentified pathogen. Expression of a specific MHC class II gene, suggestive of presentation of specific antigenic peptides to immune effectors, appears to lower the risk of transformation. Our study provides the first evidence that epithelial transformation of the California sea lion genital tract is relatively common, even from an early age, and raises questions regarding differences in sea lion cancer-detection and -repair success between geographical regions. PMID:27069641

Global boundary flattening transforms for acoustic propagation under rough sea surfaces.

PubMed

Oba, Roger M

2010-07-01

This paper introduces a conformal transform of an acoustic domain under a one-dimensional, rough sea surface onto a domain with a flat top. This non-perturbative transform can include many hundreds of wavelengths of the surface variation. The resulting two-dimensional, flat-topped domain allows direct application of any existing, acoustic propagation model of the Helmholtz or wave equation using transformed sound speeds. Such a transform-model combination applies where the surface particle velocity is much slower than sound speed, such that the boundary motion can be neglected. Once the acoustic field is computed, the bijective (one-to-one and onto) mapping permits the field interpolation in terms of the original coordinates. The Bergstrom method for inverse Riemann maps determines the transform by iterated solution of an integral equation for a surface matching term. Rough sea surface forward scatter test cases provide verification of the method using a particular parabolic equation model of the Helmholtz equation.

Hydroclimatic variability in the Levant during the early last glacial (˜ 117-75 ka) derived from micro-facies analyses of deep Dead Sea sediments

NASA Astrophysics Data System (ADS)

Neugebauer, I.; Schwab, M. J.; Waldmann, N. D.; Tjallingii, R.; Frank, U.; Hadzhiivanova, E.; Naumann, R.; Taha, N.; Agnon, A.; Enzel, Y.; Brauer, A.

2016-01-01

The new sediment record from the deep Dead Sea basin (ICDP core 5017-1) provides a unique archive for hydroclimatic variability in the Levant. Here, we present high-resolution sediment facies analysis and elemental composition by micro-X-ray fluorescence (µXRF) scanning of core 5017-1 to trace lake levels and responses of the regional hydroclimatology during the time interval from ca. 117 to 75 ka, i.e. the transition between the last interglacial and the onset of the last glaciation. We distinguished six major micro-facies types and interpreted these and their alterations in the core in terms of relative lake level changes. The two end-member facies for highest and lowest lake levels are (a) up to several metres thick, greenish sediments of alternating aragonite and detrital marl laminae (aad) and (b) thick halite facies, respectively. Intermediate lake levels are characterised by detrital marls with varying amounts of aragonite, gypsum or halite, reflecting lower-amplitude, shorter-term variability. Two intervals of pronounced lake level drops occurred at ˜ 110-108 ± 5 and ˜ 93-87 ± 7 ka. They likely coincide with stadial conditions in the central Mediterranean (Melisey I and II pollen zones in Monticchio) and low global sea levels during Marine Isotope Stage (MIS) 5d and 5b. However, our data do not support the current hypothesis of an almost complete desiccation of the Dead Sea during the earlier of these lake level low stands based on a recovered gravel layer. Based on new petrographic analyses, we propose that, although it was a low stand, this well-sorted gravel layer may be a vestige of a thick turbidite that has been washed out during drilling rather than an in situ beach deposit. Two intervals of higher lake stands at ˜ 108-93 ± 6 and ˜ 87-75 ± 7 ka correspond to interstadial conditions in the central Mediterranean, i.e. pollen zones St. Germain I and II in Monticchio, and Greenland interstadials (GI) 24+23 and 21 in Greenland, as well as to sapropels S4 and S3 in the Mediterranean Sea. These apparent correlations suggest a close link of the climate in the Levant to North Atlantic and Mediterranean climates during the time of the build-up of Northern Hemisphere ice shields in the early last glacial period.

My Summer Vacation

ERIC Educational Resources Information Center

Galus, Pamela

2010-01-01

In this article, a science teacher from the Midwest reflects on her summer vacation to the Gulf of Mexico. She felt that this vacation would help improve her teaching about the environmental problems in the gulf and elsewhere. After all, anyone can show photos of oil-laden birds and dead sea turtles and read news clips of a distant place, but to…

Potentiating Health and the Crisis of the Immune System: Integrative Approaches to Prevention and Healing of Modern Diseases.

ERIC Educational Resources Information Center

Visser, Adriaan

1997-01-01

Reports on the third Dead Sea Conference, stressing the importance of the human self-healing potential. Integrative theoretical models, integrative techniques, and workshops presented at the conference are reviewed. Presentations on cancer and immunology are reviewed. A need remains for education, counseling, and research integrating these…

"Growing" Education in Difficult Environments Promoting Problem Solving: A Case from Palestine

ERIC Educational Resources Information Center

Jabr, Dua

2009-01-01

This paper presents a collaborative educational experiment "The Death of the Dead Sea: A Problem Based Learning" that was applied in two governmental high schools in Ramallah, Palestine in the school year 2006-2007. The students' role was to raise awareness to the phenomenon of the saltiest lake that shrinks towards extinction. In spite…

Marine debris ingestion by sea turtles (Testudines) on the Brazilian coast: an underestimated threat?

PubMed

de Carvalho, Robson Henrique; Lacerda, Pedro Dutra; da Silva Mendes, Sarah; Barbosa, Bruno Corrêa; Paschoalini, Mariana; Prezoto, Fabio; de Sousa, Bernadete Maria

2015-12-30

Assessment of marine debris ingestion by sea turtles is important, especially to ensure their survival. From January to December 2011, 23 specimens of five species of sea turtles were found dead or dying after being rehabilitated, along the coast of the municipality of Rio de Janeiro, Brazil. To detect the presence of marine debris in the digestive tract of these turtles, we conducted a postmortem examination from the esophagus until the distal portion of the large intestine for each specimen. Of the total number of turtles, 39% had ingested marine debris such as soft plastic, hard plastic, metal, polyethylene terephthalate (PET) bottle caps, human hair, tampons, and latex condoms. Five of the seven sea turtles species are found along the Brazilian coast, where they feed and breed. A large number of animals are exposed to various kinds of threats, including debris ingestion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biosorption Potential of Bacillus salmalaya Strain 139SI for Removal of Cr(VI) from Aqueous Solution.

PubMed

Dadrasnia, Arezoo; Chuan Wei, Kelvin Swee; Shahsavari, Nasser; Azirun, Mohd Sofian; Ismail, Salmah

2015-12-03

The present study investigated the biosorption capacity of live and dead cells of a novel Bacillus strain for chromium. The optimum biosorption condition was evaluated in various analytical parameters, including initial concentration of chromium, pH, and contact time. The Langmuir isotherm model showed an enhanced fit to the equilibrium data. Live and dead biomasses followed the monolayer biosorption of the active surface sites. The maximum biosorption capacity was 20.35 mg/g at 25 °C, with pH 3 and contact time of 50 min. Strain 139SI was an excellent host to the hexavalent chromium. The biosorption kinetics of chromium in the dead and live cells of Bacillus salmalaya (B. salmalaya) 139SI followed the pseudo second-order mechanism. Scanning electron microscopy and fourier transform infrared indicated significant influence of the dead cells on the biosorption of chromium based on cell morphological changes. Approximately 92% and 70% desorption efficiencies were achieved using dead and live cells, respectively. These findings demonstrated the high sorption capacity of dead biomasses of B. salmalaya 139SI in the biosorption process. Thermodynamic evaluation (ΔG⁰, ΔH⁰, and ΔS⁰) indicated that the mechanism of Cr(VI) adsorption is endothermic; that is, chemisorption. Results indicated that chromium accumulation occurred in the cell wall of B. salmalaya 139SI rather than intracellular accumulation.

Biosorption Potential of Bacillus salmalaya Strain 139SI for Removal of Cr(VI) from Aqueous Solution

PubMed Central

Dadrasnia, Arezoo; Chuan Wei, Kelvin Swee; Shahsavari, Nasser; Azirun, Mohd Sofian; Ismail, Salmah

2015-01-01

The present study investigated the biosorption capacity of live and dead cells of a novel Bacillus strain for chromium. The optimum biosorption condition was evaluated in various analytical parameters, including initial concentration of chromium, pH, and contact time. The Langmuir isotherm model showed an enhanced fit to the equilibrium data. Live and dead biomasses followed the monolayer biosorption of the active surface sites. The maximum biosorption capacity was 20.35 mg/g at 25 °C, with pH 3 and contact time of 50 min. Strain 139SI was an excellent host to the hexavalent chromium. The biosorption kinetics of chromium in the dead and live cells of Bacillus salmalaya (B. salmalaya) 139SI followed the pseudo second-order mechanism. Scanning electron microscopy and fourier transform infrared indicated significant influence of the dead cells on the biosorption of chromium based on cell morphological changes. Approximately 92% and 70% desorption efficiencies were achieved using dead and live cells, respectively. These findings demonstrated the high sorption capacity of dead biomasses of B. salmalaya 139SI in the biosorption process. Thermodynamic evaluation (ΔG0, ΔH0, and ΔS0) indicated that the mechanism of Cr(VI) adsorption is endothermic; that is, chemisorption. Results indicated that chromium accumulation occurred in the cell wall of B. salmalaya 139SI rather than intracellular accumulation. PMID:26633454

Urbanisation of Suweimeh area, Jordan, versus sinkholes and landslides proliferation

NASA Astrophysics Data System (ADS)

Closson, Damien; Abou Karaki, Najib

2013-04-01

The Dead Sea is a terminal lake whose level lowers each year of about one meter per year since more than one decade. This is caused mainly by the diversion of surface waters from its watershed. Currently, 1/10 of the Jordan River still reaches the salt lake. The rapid lowering of the lake level does not allow all the surrounding groundwater tables to adjust their level to that of the Dead Sea. This imbalance causes an always faster migration of a part of the groundwater causing underground erosion leading to the formation of sinkholes along the coast, especially where discontinuities, such as faults, are present. The first collapses occurred in the years 1980-90. From the 2000s, in Jordan, they have proliferated to the point of causing serious damages to the facilities of the Arab Potash Company, the agricultural area of Ghor Al Haditha, and more recently the touristic region of Suweimeh. Aware of the problem and the need for gradual rising of the lake level, the Jordanian authorities attended from 2009 to 2011 to the feasibility study of the Red Sea - Dead Sea conduit. Currently, on the one hand, the growing environmental imbalance, and, on the other hand, the desires to develop economic activities along the coast, imply that more goods will be exposed to damages. For example, the area of Wadi Mujib Bridge was rebuilt completely in the late 2000s. It is the same for the 12 km of the dam 18 of an evaporation pond Arab Potash Company. The Numeira Salt Factory was completely destroyed in Ghor Al Haditha and was relocated to Safi. In August 2012, during touristic period, a landslide destroyed half of the Holiday Inn front beach, Suweimeh area ... End of December 2012, a team lead by Prof. Najib Abou Karaki warned the Arab Potash Company of the presence of a circular depression 250 m in diameter within the evaporation pond SP-0A. Although the dike of this saltpan is closely monitored, the exact location and shape of this large sinkhole were not known to the security managers. The frequency and intensity of the damages increase each year and therefore new hazards are expected during this decade.

Settlement on the Shores of Lake Lisan and adjacent swamps: Hindered aridization

NASA Astrophysics Data System (ADS)

Agnon, A.; Goring-Morris, N.

2014-12-01

Increased rainfall/evaporation ratio had merged the Dead Sea and Sea of Galilee basins to a 260 km long Lake Lisan during the Last Glacial Maximum, 160 m below current mean sea level (mbsl). The timing of the natural drop to the 400 mbsl (Dead Sea level) has been precisely determined to 25-11 ka. Human settlements had initiated near the retreating shorelines at 21 ka. However, rather than following the dropping level, the subsequent settlement took advantage of swamps perched above 240 mbsl.Along with an increased number of persons in the communities that left artefacts in the lacustrine and shore sediments, the technologies for exploiting the environment for survival had evolved. Some of the finds attest to activities that were not tied immediately to physical survival. The development of art and of social behaviour raises fascinating issues regarding our perception of the capabilities and motives of Mankind during the change from hunter-gatherer subsistence to one based on cultivation of plants and livestock associated with settlement.The changes in the lifestyle are likely related to the environmental changes, some of which can be reconstructed by modern geological tools. On the other hand, some of the findings of the archaeological studies can help resolve geological issues, such as aridization around 9 ka, attested by initiation of gully washers that form boulder deposits over Netiv Hagdud site. The aridization is hindered relatively to lake level drop, presumably due to evolving spatial distribution of rainfall, where the rift shoulders still receive rain, while lake decline reflects aridization in the southern drainage, namely the Negev. This observation accords with speleothem studies from the rift shoulders.

Adaptive NN controller design for a class of nonlinear MIMO discrete-time systems.

PubMed

Liu, Yan-Jun; Tang, Li; Tong, Shaocheng; Chen, C L Philip

2015-05-01

An adaptive neural network tracking control is studied for a class of multiple-input multiple-output (MIMO) nonlinear systems. The studied systems are in discrete-time form and the discretized dead-zone inputs are considered. In addition, the studied MIMO systems are composed of N subsystems, and each subsystem contains unknown functions and external disturbance. Due to the complicated framework of the discrete-time systems, the existence of the dead zone and the noncausal problem in discrete-time, it brings about difficulties for controlling such a class of systems. To overcome the noncausal problem, by defining the coordinate transformations, the studied systems are transformed into a special form, which is suitable for the backstepping design. The radial basis functions NNs are utilized to approximate the unknown functions of the systems. The adaptation laws and the controllers are designed based on the transformed systems. By using the Lyapunov method, it is proved that the closed-loop system is stable in the sense that the semiglobally uniformly ultimately bounded of all the signals and the tracking errors converge to a bounded compact set. The simulation examples and the comparisons with previous approaches are provided to illustrate the effectiveness of the proposed control algorithm.

A Final Approach Trajectory Model for Current Operations

NASA Technical Reports Server (NTRS)

Gong, Chester; Sadovsky, Alexander

2010-01-01

Predicting accurate trajectories with limited intent information is a challenge faced by air traffic management decision support tools in operation today. One such tool is the FAA's Terminal Proximity Alert system which is intended to assist controllers in maintaining safe separation of arrival aircraft during final approach. In an effort to improve the performance of such tools, two final approach trajectory models are proposed; one based on polynomial interpolation, the other on the Fourier transform. These models were tested against actual traffic data and used to study effects of the key final approach trajectory modeling parameters of wind, aircraft type, and weight class, on trajectory prediction accuracy. Using only the limited intent data available to today's ATM system, both the polynomial interpolation and Fourier transform models showed improved trajectory prediction accuracy over a baseline dead reckoning model. Analysis of actual arrival traffic showed that this improved trajectory prediction accuracy leads to improved inter-arrival separation prediction accuracy for longer look ahead times. The difference in mean inter-arrival separation prediction error between the Fourier transform and dead reckoning models was 0.2 nmi for a look ahead time of 120 sec, a 33 percent improvement, with a corresponding 32 percent improvement in standard deviation.

Impacts of abrupt climate changes in the Levant from Last Glacial Dead Sea levels

NASA Astrophysics Data System (ADS)

Torfstein, Adi; Goldstein, Steven L.; Stein, Mordechai; Enzel, Yehouda

2013-06-01

A new, detailed lake level curve for Lake Lisan (the Last Glacial Dead Sea) reveals a high frequency of abrupt fluctuations during Marine Isotope Stage 3 (MIS3) compared to the relatively high stand characterizing MIS2, and the significantly lower Holocene lake. The lake level fluctuations reflect the hydrological conditions in the large watershed of the lake, which in turn reflects the hydro-climatic conditions in the central Levant region. The new curve shows that the fluctuations coincide on millennial timescales with temperature variations recorded in Greenland. Four patterns of correlation are observed through the last ice age: (1) maximum lake elevations were reached during MIS2, the coldest interval; (2) abrupt lake level drops to the lowest elevations coincided with the occurrence of Heinrich (H) events; (3) the lake returned to higher-stand conditions along with warming in Greenland that followed H-events; (4) significant lake level fluctuations coincided with virtually every Greenland stadial-interstadial cycle. Over glacial-interglacial time-scales, Northern Hemisphere glacial cooling induces extreme wetness in the Levant, with high lake levels reaching ˜160 m below mean sea level (mbmsl), approximately 240 m above typical Holocene levels of ˜400 mbmsl. These orbital time-scale shifts are driven by expansions of the European ice sheet, which deflect westerly storm tracks southward to the Eastern Mediterranean, resulting in increased sea-air temperature gradients that invoke increased cyclogenesis, and enhanced moisture delivery to the Levant. The millennial-scale lake level drops associated with Greenland stadials are most extreme during Heinrich stadials and reflect abrupt cooling of the Eastern Mediterranean atmosphere and sea-surface, which weaken the cyclogenic rain engine and cause extreme Levant droughts. During the recovery from the effect of Heinrich stadials, the regional climate configuration resumed typical glacial conditions, with enhanced Levant precipitation and a rise in Lake Lisan levels. Similar cyclicity in the transfer of moisture to the Levant affected lake levels during all of the non-Heinrich stadial-interstadial cycles.

Sperm viability assessment in marine invertebrates by fluorescent staining and spectrofluorimetry: A promising tool for assessing marine pollution impact.

PubMed

Gallo, Alessandra; Boni, Raffaele; Tosti, Elisabetta

2018-01-01

The viability of spermatozoa is a crucial parameter to evaluate their quality that is an important issue in ecotoxicological studies. Here, a new method has been developed to rapidly determine the viability of spermatozoa in three marine invertebrates: the ascidian Ciona intestinalis, the sea urchin Paracentrotus lividus and the mollusc Mytilus galloprovincialis. This method employed the dual DNA fluorescent staining coupled with spectrofluorimetric analysis. The dual fluorescent staining used the SYBR-14 stained live spermatozoa and propidium iodide stained degenerated cells that had lost membrane integrity. Stain uptake was assessed by confocal microscopy and then the percentage of live and dead spermatozoa was quantified by spectrofluorimetric analysis. The microscopic examination revealed three populations of spermatozoa: living-SYBR-14 stained, dead-PI stained, and dying-doubly stained spermatozoa. The fluorescence emission peak values recorded in a spectrofluorimeter provide the portion of live and dead spermatozoa showing a significant negative correlation. The stain combination was further validated using known ratios of live and dead spermatozoa. The present study demonstrated that the dual DNA staining with SYBR-14 and propidium iodide was effective in assessing viability of spermatozoa in marine invertebrates and that spectrofluorimetric analysis can be successfully employed to evaluate the percentage of live and dead spermatozoa. The method develop herein is simple, accurate, rapid, sensitive, and cost-effective, so it could be a useful tool by which marine pollutants may be screened for spermiotoxicity. Copyright © 2017 Elsevier Inc. All rights reserved.

The gravity field of the Red Sea and East Africa

NASA Astrophysics Data System (ADS)

Makris, Jannis; Henke, Christian H.; Egloff, Frank; Akamaluk, Thomas

1991-11-01

Reevaluation of all gravity data from the Red Sea, the Gulf of Aden and East Africa permitted the compilation of a new Bouguer anomaly map. The intensity of the gravity field and its regional pattern correlate closely with the topographic features of the region. The maximum Bouguer values (> + 100 mGal) are located over the median troughs of the Red Sea and Gulf of Aden. Dense juvenile oceanic crust in these rifts and intruding magmas in stretched continental areas produce excess mass responsible for the anomaly highs. In the Red Sea the orientation of the gravity highs is NW-SE in the south, turning to NE-SW in the north, almost parallel to the Aqaba-Dead Sea strike. This pattern reveals that the present basin axis is not identical with that which formed the Tertiary coastal margins and the pre-Red Sea zones of crustal weakness. In the Gulf of Aden, new oceanic crust along the Tadjura Trench and its eastward extension is also expressed in the Bouguer anomaly map by gravity highs and a sharp bending of the isolines. A maximum of approx. +150 mGal is located over the central section of the Sheba Ridge. Bouguer gravity values over the East African and Yemen Plateaus are of the order of -180 to -240 mGal, indicating significant crustal thickening. On the Somali Plateau, the Marda Fault also has a strong gravity signature that can be traced towards Somalia. By constraining crustal thickness and structure with seismic data and density values from the velocity distribution by means of the Nafe-Drake and Birch relationships, we computed density models for the crust and upper mantle. The crustal thickness is of the order of 40 km beneath the plateaus and only 5 to 6 km at the oceanized parts in the central and southern portions of the Red Sea median trough. The flanks of the southern Red Sea and the corresponding Arabian side are underlain by 12 to 16 km thick stretched continental type crust. Oceanization offshore Sudan and Egypt is asymmetrical. The continental crust terminates abruptly at about 20 km off the coastline, followed by an oceanic crust of early Miocene age that was produced in pull-apart basins. By contrast, the eastern side of the Red Sea trough offshore Saudi Arabia is floored by stretched continental crust that extends far into the sea. Seafloor spreading and the generation of oceanic crust in organized spreading centres are limited to the median troughs off Sudan and the northern part of Ethiopia and commenced approx. 5 m.y. BP. They are absent in the northern Red Sea, where crustal fracturing occurs only in pull-apart basins of Dead Sea-Aqaba orientation distributed in en-echelon pattern.

Identification of ancient textile fibres from Khirbet Qumran caves using synchrotron radiation microbeam diffraction

NASA Astrophysics Data System (ADS)

Müller, Martin; Murphy, Bridget; Burghammer, Manfred; Riekel, Christian; Roberts, Mark; Papiz, Miroslav; Clarke, David; Gunneweg, Jan; Pantos, Emmanuel

2004-10-01

Archaeological textiles fragments from the caves of Qumran in the Dead Sea region were investigated by means of X-ray microbeam diffraction on single fibres. This non-destructive technique made the identification of the used plant textile fibres possible. Apart from bast fibres (mainly flax), cotton was identified which was most unexpected in the archaeological context.

Use of Concept Profile Analysis to Identify Difficulties in Solving Science Problems.

ERIC Educational Resources Information Center

Gorodetsky, Malka; Hoz, Ron

1980-01-01

Proposed is a new method for analyzing how concepts are used in the process of problem solving in science. Through the use of a "thinking aloud" interview technique, 21 tenth-grade students worked with a problem concerning the boiling point of water at the Dead Sea. Interview protocols were analyzed to develop students' concept profiles.…

Seasonal and plant-dependent variations in diversity, abundance and stress tolerance of epiphytic yeasts in desert habitats.

PubMed

Abu-Ghosh, Said; Droby, Samir; Korine, Carmi

2014-08-01

We studied the epiphytic yeast species of the plants of the Negev Desert and the Dead Sea region, Israel, which are considered one of the most extreme hyper-arid lands in the world. For this purpose, we developed isolation protocols; we performed morphological, cultural and molecular identification tests and compared yeast diversity between the locations and the plants. The composition of the yeast populations present in the study's plants underwent seasonal fluctuations, whereas differences in community compositions were significant within sites. The maximum number of species of yeast occurred in autumn and Cryptococcus spp. were predominant year round. The isolated yeast strains showed an unusual tolerance to extreme growth conditions, such as high temperatures (up to 72% viability at 50°C), lethal hydrogen peroxide and NaCl concentrations. These results suggest that epiphytic yeasts inhabit the plants of the Dead Sea region and the Negev Desert have a community structure that is unique to the plant species and have a high tolerance to the harsh conditions that enables them to adapt to an arid ecosystem. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

Oryong 501 sinking incident in the Bering Sea-International DVI cooperation in the Asia Pacific.

PubMed

Chung, Nak-Eun; Castilani, Anton; Tierra, Wilfredo E; Beh, Philip; Mahmood, Mohd Shah

2017-09-01

On December 1st, 2014, the sinking of Oryong 501 occurred in the Bering Sea off the east coast of Russia. A total of 60 crew members, including 35 Indonesians, 13 Filipinos, 11 South Koreans and 1 Russian inspector were on board out of which only seven survived. Through an international rescue operation, the dead bodies of 27 were found and the remaining 26 crew are still missing. After transferring the dead bodies to the Busan Harbor in South Korea, the operation to identify the deceased began involving DVI teams from three countries: Korea, Indonesia and the Philippines. When a deep sea fishing boat sinks, it is very difficult to obtain antemortem data of the crew who had been on board for a long time. This is especially so if the crews are multinational. Further, the accuracy of the antemortem data provided by the families may be questionable, and the provided data is often not standardized. Despite the fact that the antemortem data were received in different formats, the identification process for the bodies of the 27 crew from the Oryong sinking was quickly completed through the cooperation among the three DVI teams. This case is an excellent example of how efficiently a DVI operation can be conducted in the Asia Pacific region. Issues raised during this operation should enable even better preparation for similar events in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

Amorphous calcium carbonate transforms into calcite during sea urchin larval spicule growth

PubMed Central

Beniash, E.; Aizenberg, J.; Addadi, L.; Weiner, S.

1997-01-01

Sea urchin larvae form an endoskeleton composed of a pair of spicules. For more than a century it has been stated that each spicule comprises a single crystal of the CaCO3 mineral, calcite. We show that an additional mineral phase, amorphous calcium carbonate, is present in the sea urchin larval spicule, and that this inherently unstable mineral transforms into calcite with time. This observation significantly changes our concepts of mineral formation in this well-studied organism.

Southeastern Mediterranean Panorama

NASA Image and Video Library

1991-06-14

STS040-152-180 (5-24 June 1991) --- The Sinai Peninsula dominates this north-looking, oblique view. According to NASA photo experts studying the STS 40 imagery, the Red Sea in the foreground is clear of river sediment because of the prevailing dry climate of the Middle East. The great rift of the Gulf of Aqaba extends northward to Turkey (top right) through the Dead Sea. The international boundary between Israel and Egypt, reflecting different rural landscapes, stands out clearly. The Nile River runs through the frame. NASA photo experts believe the haze over the Mediterranean to be wind-borne dust. The photo was taken with an Aero-Linhof large format camera.

The coastal oasis: ice age springs on emerged continental shelves

NASA Astrophysics Data System (ADS)

Faure, Hugues; Walter, Robert C.; Grant, Douglas R.

2002-06-01

As ice caps expanded during each of the last five glaciations, sea level fell at least 120 m below current levels, exposing continental shelves worldwide to create vast areas of new land. As a result of this exposure, the ecology, climate, pedology, and geology of global shorelines were dramatically transformed, which in turn altered the carbon cycle and biodynamics of this new landmass. In this paper, we focus on a little-known hydrogeological phenomenon that may have had profound influences on biodiversity, human evolution, and carbon storage during periods of severe climatic stress of the Pleistocene Ice Ages. We propose that freshwater springs appeared on emerged continental shelves because falling sea level not only drew down and steepened the coastal water table gradient, thus increasing the hydrostatic head on inland groundwater aquifers, but also removed up to 120 m of hydrostatic pressure on the shelf, further enhancing groundwater flow. We call this phenomenon the "coastal oasis", a model based on three well-established facts. (1) In all coastal areas of the world, continental aquifers discharge a continuous flow of fresh water to the oceans. (2) Many submarine sedimentary and morphological features, as well as seepages and flow of fresh water, are known on and below the shelves from petroleum explorations, deep-sea drilling programs, and mariners' observations. (3) Hydraulic principles (Darcy's law) predict increased groundwater flow at the coast when sea level drops because the piezometric head increases by the equivalent depth of sea-level lowering. Sea level is presently in a relatively high interglacial position. Direct observation and verification of our model is difficult and must rely on explorations of terrain that are now deeply submerged on continental shelves. For this reason, we draw parallels between our predicted model and simple, well-exposed terrestrial hydrological systems, such as present-day springs that appear on the exposed shores of lakes whose free-air water levels fell during periods of aridity. Such modern examples are seen in the Caspian Sea and Dead Sea, the Afar Depression, and the Sahara Desert. These modern analogues demonstrate the likelihood that underground water will be more abundant on emerged shelves during sea-level fall, causing springs, oases, and wetlands to appear. Our model creates an apparent paradox: in tropical and subtropical arid lands, such as most of Africa, sea-level fall during hyperarid glacial phases would produce abundant fresh water flow onto emerged continental shelves as the continental interior desiccated. Thus, emergent shoreline springs provided new habitats for terrestrial vegetation and animals displaced from the interior by increasingly arid conditions, shrinking ecosystems, and dwindling water supplies. Such a scenario would have had a profound influence on the vegetation that spreads naturally to colonize the emerged shelves during glacio-eustatic sea-level lowstands, as well as creating new habitats for terrestrial mammals, including early humans.

Lithology-derived structure classification from the joint interpretation of magnetotelluric and seismic models

USGS Publications Warehouse

Bedrosian, P.A.; Maercklin, N.; Weckmann, U.; Bartov, Y.; Ryberg, T.; Ritter, O.

2007-01-01

Magnetotelluric and seismic methods provide complementary information about the resistivity and velocity structure of the subsurface on similar scales and resolutions. No global relation, however, exists between these parameters, and correlations are often valid for only a limited target area. Independently derived inverse models from these methods can be combined using a classification approach to map geologic structure. The method employed is based solely on the statistical correlation of physical properties in a joint parameter space and is independent of theoretical or empirical relations linking electrical and seismic parameters. Regions of high correlation (classes) between resistivity and velocity can in turn be mapped back and re-examined in depth section. The spatial distribution of these classes, and the boundaries between them, provide structural information not evident in the individual models. This method is applied to a 10 km long profile crossing the Dead Sea Transform in Jordan. Several prominent classes are identified with specific lithologies in accordance with local geology. An abrupt change in lithology across the fault, together with vertical uplift of the basement suggest the fault is sub-vertical within the upper crust. ?? 2007 The Authors Journal compilation ?? 2007 RAS.

On the nature of rainfall in dry climate: Space-time patterns of convective rain cells over the Dead Sea region and their relations with synoptic state and flash flood generation

NASA Astrophysics Data System (ADS)

Belachsen, Idit; Marra, Francesco; Peleg, Nadav; Morin, Efrat

2017-04-01

Space-time patterns of rainfall are important climatic characteristics that influence runoff generation and flash flood magnitude. Their derivation requires high-resolution measurements to adequately represent the rainfall distribution, and is best provided by remote sensing tools. This need is further emphasized in dry climate regions, where rainfall is scarce and, often, local and highly variable. Our research is focused on understanding the nature of rainfall events in the dry Dead Sea region (Eastern Mediterranean) by identifying and characterizing the spatial structure and the dynamics of convective storm cores (known as rain cells). To do so, we take advantage of 25 years of corrected and gauge-adjusted weather radar data. A statistical analysis of convective rain-cells spatial and temporal characteristics was performed with respect to synoptic pattern, geographical location, and flash flood generation. Rain cells were extracted from radar data using a cell segmentation method and a tracking algorithm and were divided into rain events. A total of 10,500 rain cells, 2650 cell tracks and 424 rain events were elicited. Rain cell properties, such as mean areal and maximal rain intensity, area, life span, direction and speed, were derived. Rain events were clustered, according to several ERA-Interim atmospheric parameters, and associated with three main synoptic patterns: Cyprus Low, Low to the East of the study region and Active Red Sea Trough. The first two originate from the Mediterranean Sea, while the third is an extension of the African monsoon. On average, the convective rain cells in the region are 90 km2 in size, moving from West to East in 13 ms-1 and living 18 minutes. Several significant differences between rain cells of the various synoptic types were observed. In particular, Active Red Sea Trough rain cells are characterized by higher rain intensities and lower speeds, suggesting a higher flooding potential for small catchments. The north-south negative gradient of mean annual rainfall in the study region was found to be negatively correlated with rain cells intensity and positively correlated with rain cells area. Additional analysis was done for convective rain cells over two nearby catchments located in the central part of the study region, by ascribing some of the rain events to observed flash-flood events. It was found that rain events associated with flash-floods have higher maximal rain cell intensity and lower minimal cell speed than rain events that did not lead to a flash-flood in the watersheds. This information contributes to our understanding of rain patterns over the dry area of the Dead Sea and their connection to flash-floods. The statistical distributions of rain cells properties can be used for high space-time resolution stochastic simulations of rain storms that can serve as an input to hydrological models.

Seismic anisotropy along the Cyprean arc and northeast Mediterranean Sea inferred from shear wave splitting analysis

NASA Astrophysics Data System (ADS)

Yolsal-Çevikbilen, Seda

2014-08-01

The Cyprean arc is considered to be a convergent boundary in the Eastern Mediterranean where the African plate is being subducted beneath the Anatolian plate. Mapping the lateral variations of seismic anisotropy parameters can provide essential hints to mantle dynamics and flow patterns in relation to the geometry and style of deformation developed under different pressure, temperature conditions around the subducting African lithosphere. In this study, seismic anisotropy parameters, fast polarization directions (ϕ) and delay times (δt) beneath the Cyprean arc and NE Mediterranean Sea are inferred from the shear wave splitting analysis performed on core-mantle refracted teleseismic shear waves (SKS phases). Earthquake data used in the present work are extracted from the continuous recordings of 8 broad-band seismic stations located in the study region for a time period during 1999 and 2012. The overall results exhibits clear evidences of mantle anisotropy with relatively uniform NE-SW aligned fast polarization directions. No abrupt changes in fast polarization directions (ϕ) are observed. However, near the Dead Sea Transform Fault, ϕ values tend to rotate from NE-SW to N-S and NW-SE in accordance with Pn anisotropy observations. Delay times (δt) vary between 0.61 s ± 0.10 s and 1.90 s ± 0.13 s. The range of delay times are generally consistent with those observed in the mantle rather than implying a crustal anisotropy. A predominant pattern of NNE-SSW fast polarization directions that is coherent with earlier SKS splitting measurements observed beneath north, central and East Anatolia suggests a SW directed asthenospheric flow caused by slab rollback process along the Hellenic and Cyprean arcs. Furthermore, apparent splitting parameters did not exhibit any significant directional dependence which may imply possibility of the presence of anisotropic models with two-layer anisotropy or dipping axis of symmetry beneath the northeast Mediterranean Sea and Cyprean arc. Consequently, a simple, single-layered and sub-horizontal anisotropy model is tentatively suggested for the study region.

Assessing the living and dead proportions of cold-water coral colonies: implications for deep-water Marine Protected Area monitoring in a changing ocean.

PubMed

Vad, Johanne; Orejas, Covadonga; Moreno-Navas, Juan; Findlay, Helen S; Roberts, J Murray

2017-01-01

Coral growth patterns result from an interplay of coral biology and environmental conditions. In this study colony size and proportion of live and dead skeletons in the cold-water coral (CWC) Lophelia pertusa (Linnaeus, 1758) were measured using video footage from Remotely Operated Vehicle (ROV) transects conducted at the inshore Mingulay Reef Complex (MRC) and at the offshore PISCES site (Rockall Bank) in the NE Atlantic. The main goal of this paper was to explore the development of a simple method to quantify coral growth and its potential application as an assessment tool of the health of these remote habitats. Eighteen colonies were selected and whole colony and dead/living layer size were measured. Live to dead layer ratios for each colony were then determined and analysed. The age of each colony was estimated using previously published data. Our paper shows that: (1) two distinct morphotypes can be described: at the MRC, colonies displayed a 'cauliflower-shaped' morphotype whereas at the PISCES site, colonies presented a more flattened 'bush-shaped' morphotype; (2) living layer size was positively correlated with whole colony size; (3) live to dead layer ratio was negatively correlated to whole colony size; (4) live to dead layer ratio never exceeded 0.27. These results suggest that as a colony develops and its growth rate slows down, the proportion of living polyps in the colony decreases. Furthermore, at least 73% of L. pertusa colonies are composed of exposed dead coral skeleton, vulnerable to ocean acidification and the associated shallowing of the aragonite saturation horizon, with significant implications for future deep-sea reef framework integrity. The clear visual contrast between white/pale living and grey/dark dead portions of the colonies also gives a new way by which they can be visually monitored over time. The increased use of marine autonomous survey vehicles offers an important new platform from which such a surveying technique could be applied to monitor deep-water marine protected areas in the future.

Earth Observations taken by STS-115 crewmember

NASA Image and Video Library

2006-09-19

S115-E-07595 (19 Sept. 2006) --- A crewmember aboard the Space Shuttle Atlantis recorded this digital still image of part of the eastern Mediterranean area. The Gulf of Suez, Gulf of Aqaba, Dead Sea, Tel Aviv and Jerusalem all are visible in the upper left quadrant. Jordan is in the lower left quadrant. The Golan Heights and Haifa appear in the lower right quarter.

Evidence of spring formation and subrosion-induced sinkhole development at Ghor Al-Haditha, Jordan, from repeated close-range photogrammetry

NASA Astrophysics Data System (ADS)

Al-Halbouni, Djamil; Eoghan, P. Holohan; Leila, Saberi; Hussam, Alrshdan; Thomas, Walter; Ali, Sawarieh; Torsten, Dahm

2016-04-01

The widespread development of sinkholes and land subsidence poses a major geological hazard to infrastructure, local population, agriculture and industry in the Dead Sea area. For assessment of the key physical factors in this development, repeated photogrammetric and field surveys at Ghor Al-Haditha in Jordan have been undertaken. Recent results provide evidence for subrosion based on strong periodic water flows, as the basic underlying physical process of such land subsidence phenomena. From combined Helikite- and Quatrocopter-based photogrammetric surveys, high resolution Digital Surface Models from October 2014 and October 2015 are compared. Change detection reveals: (1) active subsidence in a hundred metre-scale depression zone, (2) a highly-dynamic spring and canyon system connected with recent sinkhole collapses and (3) the rapid formation of new sinkholes both in alluvium and mud cover sediments. The formation of new sinkholes has been documented locally by means of aerial and field observations during a storm with strong rainfall. A new artesian spring formed in the former Dead Sea bed (mud-flat) at this event. The alluvial sediment load of the stream, a periodic location change of the spring and a connected uphill sinkhole cluster formation provide strong evidence for subrosion of weak material with subsequent underground void collapse. Additionally a documented lake and its' subsequent drainage forming a new canyon reveals the local penetration of the aquiclude behavior of the mud-flat in the major depression area, which can be explained by an under-saturated groundwater flow at a strong hydrostatic gradient. Furthermore an enlargement of the investigated area in the 2015 survey indicates a continuation of subsidence and sinkhole activity towards the North. It reveals several points of emanation of water streams in the mud-flat beneath the alluvial cover and vegetation as an indicator of relatively fresh groundwater inflow. This repeated photogrammetry and field survey confirms the hypothesis of a large-scale, channelized subterranean water flow in a 3d network of interconnected tubes. This subsurface karstic channel network is hence responsible for sinkhole formation and rapid land subsidence at the Ghor Al-Haditha sinkhole area and perhaps elsewhere around the Dead Sea.

The Thermal Waters of Jordan

NASA Astrophysics Data System (ADS)

Sass, I.; Schäffer, R.

2012-04-01

In a recent field campaign all known natural hot spring areas of Jordan were investigated. Their hydrochemical properties including some fundamental isotopes were measured. Jordan's thermal springs can be classified into four thermal provinces (Nahr Al-Urdun, Hammamat Ma'in, Zara and Wadi Araba province), with similar hydrochemical and geologicalsettings. Thermal springs of Hammamat Ma'in and Zara province are situated on prominent faults. Reservoir temperature estimation with the Mg-corrected Na-K-Ca geothermometer indicates temperatures between 61 °C and 82 °C. Even taking into account the increased geothermal gradient at Dead Sea's east coast, the water's origin has to be considered mainly in deeper formations. Carbon dioxide, emitted by tertiary basalts situated close to the springs, may be responsible for gas lift. Mineralisation and δ18O-values indicate, that the spring water's origin is mostly fossil, i.e. not part of the global water cycle. It is shown, that ground water mining led to a shift within δ18O-ratio during the last 30 years due to a reduction of shallow water portion in addition to a dislocation of the catchment area. Ground water mining will impact the thermal spring productivity and quality anyway in the future. Present-day precipitation rates and catchment areas in Dead Sea region are by far not sufficient to explain relative high discharge. For the Hammamat Ma'in Province is documented, that discharge and maximal spring water temperatures are constant during the last 50 years, showing marginal seasonal oscillation and negligible influence by short-term climatic changes. The water characteristics of Hammamat Ma'in and Zara province are related. However, Zara waters feature systematically less ion concentration and lower temperatures due to a stronger influence of vadose water. The springs of Nahr Al-Urdun province are recharged mainly by shallow groundwater. Thus temperature and mineralisation is lower than at the springs at the Dead Sea. Thermal waters of Wadi Araba province show the lowest mineralisation due to their origin of mostly sandstones. The main ion's proportion and δ18O-ratio indicate a mixture of fossil and vadose groundwater.

Sinkholes, subsidence and subrosion on the eastern shore of the Dead Sea as revealed by a close-range photogrammetric survey

NASA Astrophysics Data System (ADS)

Al-Halbouni, Djamil; Holohan, Eoghan P.; Saberi, Leila; Alrshdan, Hussam; Sawarieh, Ali; Closson, Damien; Walter, Thomas R.; Dahm, Torsten

2017-05-01

Ground subsidence and sinkhole collapse are phenomena affecting regions of karst geology worldwide. The rapid development of such phenomena around the Dead Sea in the last four decades poses a major geological hazard to the local population, agriculture and industry. Nonetheless many aspects of this hazard are still incompletely described and understood, especially on the eastern Dead Sea shore. In this work, we present a first low altitude (< 150 m above ground) aerial photogrammetric survey with a Helikite Balloon at the sinkhole area of Ghor Al-Haditha, Jordan. We provide a detailed qualitative and quantitative analysis of a new, high resolution digital surface model (5 cm px-1) and orthophoto of this area (2.1 km2). We also outline the factors affecting the quality and accuracy of this approach. Our analysis reveals a kilometer-scale sinuous depression bound partly by flexure and partly by non-tectonic faults. The estimated minimum volume loss of this subsided zone is 1.83 ṡ 106 m3 with an average subsidence rate of 0.21 m yr-1 over the last 25 years. Sinkholes in the surveyed area are localized mainly within this depression. The sinkholes are commonly elliptically shaped (mean eccentricity 1.31) and clustered (nearest neighbor ratio 0.69). Their morphologies and orientations depend on the type of sediment they form in: in mud, sinkholes have a low depth to diameter ratio (0.14) and a long-axis azimuth of NNE-NE. In alluvium, sinkholes have a higher ratio (0.4) and are orientated NNW-N. From field work, we identify actively evolving artesian springs and channelized, sediment-laden groundwater flows that appear locally in the main depression. Consequently, subrosion, i.e. subsurface mechanical erosion, is identified as a key physical process, in addition to dissolution, behind the subsidence and sinkhole hazard. Furthermore, satellite image analysis links the development of the sinuous depression and sinkhole formation at Ghor Al-Haditha to preferential groundwater flow paths along ancient and current wadi riverbeds.

Hsp90 and hepatobiliary transformation during sea lamprey metamorphosis.

PubMed

Chung-Davidson, Yu-Wen; Yeh, Chu-Yin; Bussy, Ugo; Li, Ke; Davidson, Peter J; Nanlohy, Kaben G; Brown, C Titus; Whyard, Steven; Li, Weiming

2015-12-01

Biliary atresia (BA) is a human infant disease with inflammatory fibrous obstructions in the bile ducts and is the most common cause for pediatric liver transplantation. In contrast, the sea lamprey undergoes developmental BA with transient cholestasis and fibrosis during metamorphosis, but emerges as a fecund adult. Therefore, sea lamprey liver metamorphosis may serve as an etiological model for human BA and provide pivotal information for hepatobiliary transformation and possible therapeutics. We hypothesized that liver metamorphosis in sea lamprey is due to transcriptional reprogramming that dictates cellular remodeling during metamorphosis. We determined global gene expressions in liver at several metamorphic landmark stages by integrating mRNA-Seq and gene ontology analyses, and validated the results with real-time quantitative PCR, histological and immunohistochemical staining. These analyses revealed that gene expressions of protein folding chaperones, membrane transporters and extracellular matrices were altered and shifted during liver metamorphosis. HSP90, important in protein folding and invertebrate metamorphosis, was identified as a candidate key factor during liver metamorphosis in sea lamprey. Blocking HSP90 with geldanamycin facilitated liver metamorphosis and decreased the gene expressions of the rate limiting enzyme for cholesterol biosynthesis, HMGCoA reductase (hmgcr), and bile acid biosynthesis, cyp7a1. Injection of hsp90 siRNA for 4 days altered gene expressions of met, hmgcr, cyp27a1, and slc10a1. Bile acid concentrations were increased while bile duct and gall bladder degeneration was facilitated and synchronized after hsp90 siRNA injection. HSP90 appears to play crucial roles in hepatobiliary transformation during sea lamprey metamorphosis. Sea lamprey is a useful animal model to study postembryonic development and mechanisms for hsp90-induced hepatobiliary transformation.

Measurement of fish movements at depths to 6000 m using a deep-ocean lander incorporating a short base-line sonar utilizing miniature code-activated transponder technology

NASA Astrophysics Data System (ADS)

Bagley, P. M.; Bradley, S.; Priede, I. G.; Gray, P.

1999-12-01

Most research on animal behaviour in the deep ocean (to depths of 6000 m) is restricted to the capture of dead specimens or viewing activity over small areas of the sea floor by means of cameras or submersibles. This paper describes the use of a miniature acoustic code-activated transponder (CAT) tag and short base-line sonar to track the movements of deep-sea fish in two dimensions over an area 1 km in diameter centred on a lander platform. The CAT tags and sonar are transported to the deep-sea floor by means of a subsea mooring which is ballasted so that it lands and remains on the sea floor for the duration of the tracking experiment (the lander). A description of the CAT, lander and short base-line sonar is given. Results are presented to illustrate the operation of the system.

Transformation mechanism of amorphous calcium carbonate into calcite in the sea urchin larval spicule.

PubMed

Politi, Yael; Metzler, Rebecca A; Abrecht, Mike; Gilbert, Benjamin; Wilt, Fred H; Sagi, Irit; Addadi, Lia; Weiner, Steve; Gilbert, P U P A; Gilbert, Pupa

2008-11-11

Sea urchin larval spicules transform amorphous calcium carbonate (ACC) into calcite single crystals. The mechanism of transformation is enigmatic: the transforming spicule displays both amorphous and crystalline properties, with no defined crystallization front. Here, we use X-ray photoelectron emission spectromicroscopy with probing size of 40-200 nm. We resolve 3 distinct mineral phases: An initial short-lived, presumably hydrated ACC phase, followed by an intermediate transient form of ACC, and finally the biogenic crystalline calcite phase. The amorphous and crystalline phases are juxtaposed, often appearing in adjacent sites at a scale of tens of nanometers. We propose that the amorphous-crystal transformation propagates in a tortuous path through preexisting 40- to 100-nm amorphous units, via a secondary nucleation mechanism.

Sea Ice Drift Monitoring in the Bohai Sea Based on GF4 Satellite

NASA Astrophysics Data System (ADS)

Zhao, Y.; Wei, P.; Zhu, H.; Xing, B.

2018-04-01

The Bohai Sea is the inland sea with the highest latitude in China. In winter, the phenomenon of freezing occurs in the Bohai Sea due to frequent cold wave influx. According to historical records, there have been three serious ice packs in the Bohai Sea in the past 50 years which caused heavy losses to our economy. Therefore, it is of great significance to monitor the drift of sea ice and sea ice in the Bohai Sea. The GF4 image has the advantages of short imaging time and high spatial resolution. Based on the GF4 satellite images, the three methods of SIFT (Scale invariant feature - the transform and Scale invariant feature transform), MCC (maximum cross-correlation method) and sift combined with MCC are used to monitor sea ice drift and calculate the speed and direction of sea ice drift, the three calculation results are compared and analyzed by using expert interpretation and historical statistical data to carry out remote sensing monitoring of sea ice drift results. The experimental results show that the experimental results of the three methods are in accordance with expert interpretation and historical statistics. Therefore, the GF4 remote sensing satellite images have the ability to monitor sea ice drift and can be used for drift monitoring of sea ice in the Bohai Sea.

Recovering from Tragedy

ERIC Educational Resources Information Center

Kennedy, Mike

2012-01-01

When a catastrophe strikes a community, the response of those affected may vary. But whether it is a hurricane, deadly violence, or killer tornados, the schools have to push forward and transform a traumatic situation into an opportunity for improvements. Schools and universities must move forward to make sure students continue to learn and grow.…

Composition and transformation of dissolved organic matter in the Baltic Sea

NASA Astrophysics Data System (ADS)

Seidel, Michael; Manecki, Marcus; Herlemann, Daniel P. R.; Deutsch, Barbara; Schulz-Bull, Detlef; Jürgens, Klaus; Dittmar, Thorsten

2017-05-01

The processing of terrestrial dissolved organic matter (DOM) in coastal shelf seas is an important part of the global carbon cycle, yet, it is still not well understood. One of the largest brackish shelf seas, the Baltic Sea in northern Europe, is characterized by high freshwater input from sub-arctic rivers and limited water exchange with the Atlantic Ocean via the North Sea. We studied the molecular and isotopic composition and turnover of solid-phase extractable (SPE) DOM and its transformation along the salinity and redox continuum of the Baltic Sea during spring and autumn. We applied ultrahigh-resolution mass spectrometry and other geochemical and biological approaches. Our data demonstrate a large influx of terrestrial riverine DOM, especially into the northern part of the Baltic Sea. The DOM composition in the central Baltic Sea changed seasonally and was mainly related to autochthonous production by phytoplankton in spring. Especially in the northern, river-dominated basins, a major fraction of riverine DOM was removed, likely by bio- and photo-degradation. We estimate that the removal rate of terrestrial DOM in the Baltic Sea (Bothnian Bay to the Danish Straits/Kattegat area) is 1.6 - 1.9 Tg C per year which is 43 to 51% of the total riverine input. The export of terrestrial DOM from the Danish Straits/Kattegat area towards the North Sea is 1.8 - 2.1 Tg C per year. Due to the long residence time of terrestrial DOM in the Baltic Sea (total of ca. 12 years), seasonal variations caused by bio- and photo-transformations and riverine discharge are dampened, resulting in a relatively invariant DOM molecular and isotopic signature exported to the North Sea. In the deep stagnant basins of the Baltic Sea, the DOM composition and dissolved organic nitrogen concentrations changed seasonally, likely because of vertical particle transport and subsequent degradation releasing DOM. DOM in the deep anoxic basins was also enriched in sulfur-containing organic molecules, pointing to abiotic sulfurization of DOM under sulfidic conditions.

Biosorption of Cd(II) by live and dead cells of Bacillus cereus RC-1 isolated from cadmium-contaminated soil.

PubMed

Huang, Fei; Dang, Zhi; Guo, Chu-Ling; Lu, Gui-Ning; Gu, Roy R; Liu, Hong-Juan; Zhang, Hui

2013-07-01

The present study investigated the biosorption capacity of live and dead cells of Bacillus cereus RC-1 for Cd(II). The biosorption characteristics were investigated as a function of initial pH, contact time, and initial cadmium concentration. Equilibrium biosorption was modeled using Langmuir, Freundlich and Redlich-Peterson isotherm equations. It was found that the maximum biosorption capacities calculated from Langmuir isotherm were 31.95 mg/g and 24.01 mg/g for dead cells and live cells, respectively. The kinetics of the biosorption was better described by pseudo-second order kinetic model. Desorption efficiency of biosorbents was investigated at various pH values. These results indicated that dead cells have higher Cd(II) biosorption capacity than live cells. Furthermore, zeta potential, transmission electron microscopy (TEM), scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX), and Fourier transform infrared spectroscopy (FTIR) studies were carried out to understand the differences in the Cd(II) biosorption behavior for the both biosorbents. The bioaccumulation of Cd(II) by B. cereus RC-1 was found to depend largely on extracellular biosorption rather than intracellular accumulation. Based on the above studies, dead biomass appears to be a more efficient biosorbent for the removal of Cd(II) from aqueous solution. Copyright © 2013 Elsevier B.V. All rights reserved.

Adaptive Control via Neural Output Feedback for a Class of Nonlinear Discrete-Time Systems in a Nested Interconnected Form.

PubMed

Li, Dong-Juan; Li, Da-Peng

2017-09-14

In this paper, an adaptive output feedback control is framed for uncertain nonlinear discrete-time systems. The considered systems are a class of multi-input multioutput nonaffine nonlinear systems, and they are in the nested lower triangular form. Furthermore, the unknown dead-zone inputs are nonlinearly embedded into the systems. These properties of the systems will make it very difficult and challenging to construct a stable controller. By introducing a new diffeomorphism coordinate transformation, the controlled system is first transformed into a state-output model. By introducing a group of new variables, an input-output model is finally obtained. Based on the transformed model, the implicit function theorem is used to determine the existence of the ideal controllers and the approximators are employed to approximate the ideal controllers. By using the mean value theorem, the nonaffine functions of systems can become an affine structure but nonaffine terms still exist. The adaptation auxiliary terms are skillfully designed to cancel the effect of the dead-zone input. Based on the Lyapunov difference theorem, the boundedness of all the signals in the closed-loop system can be ensured and the tracking errors are kept in a bounded compact set. The effectiveness of the proposed technique is checked by a simulation study.

Sinai Peninsula, Middle East as seen from STS-66 orbiter Atlantis

NASA Image and Video Library

1994-11-14

A high oblique view of the Middle East centered at approximately 28.0 degrees north and 34.0 degrees east. Portions of the countries of Egypt, Israel, Jordan and Saudi Arabia are visible. The Dead Sea Rift Valley continuing into the Gulf of Aqaba marks the boundary between Israel and Jordan. The vegetation change in the Sinai Peninsula is the border between the Gaza Strip and Egypt. In Egypt, the Suez Canal connects the Gulf of Suez with the Mediterranean Sea and forms the western boundary of the Sinai Peninsula. The green ribbon of the Nile River is in marked contrast to this arid region. Even the Jordan River does not support large scale agriculture.

Distribution of bacterial biomass and activity in the marginal ice zone of the central Barents Sea during summer

NASA Astrophysics Data System (ADS)

Howard-Jones, M. H.; Ballard, V. D.; Allen, A. E.; Frischer, M. E.; Verity, P. G.

2002-12-01

The purpose of this study was to determine bacterioplankton abundance and activity in the Barents Sea using the novel modified vital stain and probe (mVSP) method. The mVSP is a protocol that combines DAPI and propidium iodide staining with 16S rRNA eubacterial-specific oligonucleotide probes to determine the physiological status of individual microbial cells. Bacterial abundance and metabolic activity were measured in near-surface waters and with depth at stations in the central Barents Sea during a cruise in June/July 1999. Viral abundance was also determined for 19 transect stations and at depth (2-200 m) for five intensive 24-h stations. In general, bacterial and viral abundances varied across the transect, but showed peaks of abundance (6×10 9 cells l -1, 9×10 9 viruses l -1) in Polar Front water masses. Viruses were abundant in seawater and exceeded bacterial abundance. Metabolic activity was determined for individual cells using 16S rRNA eubacterial-specific oligonucleotide probes, and for the total community with 3H-leucine incorporation. Activity measured by oligonucleotide probes increased from south to north. The fraction of cells that were active was lowest in the southern Barents Sea (20%) and highest in the Polar Front (53%). The proportion of cells at the 24-h stations that were determined to be active decreased with depth, but not with distance from ice cover. Leucine incorporation rates varied significantly and did not always correlate with probe measurements. The proportion of total cells that had compromised membranes and were therefore considered dead remained relatively constant (<10%) across the transect. The percent of dead cells in the near surface waters and at depth were statistically similar. The percent dead cells made up only a small fraction of the total population at the 24-h stations. The largest and most variable fraction of cells were those classified as low activity (25-80%), which supports the hypothesis that a significant fraction of cells in aquatic ecosystems are inactive. Bacterioplankton production rates ranged from <0.05 to 2.8 mg C m -3 day -1. Growth rates ranged from <0.05 to 0.25 day -1, implying turnover rates of 2.5 to >200 days. Our results demonstrate that bacterioplankton and viruses are dynamic but ubiquitous features of Arctic microbial communities. The contribution of bacteria and viruses to Arctic food webs is discussed.

Undergraduate Research Experience in Ocean/Marine Science (URE-OMS) with African Student Component

DTIC Science & Technology

2008-01-01

Intergovernmental Panel on Climate Change (IPCC). RESULTS Temporal and Spatial Variations of Sea Surface Temperature and Chlorophyll a in Coastal Waters of...Duck, North Carolina [4] Climate change has affected the North Carolina coastal environments and coastal hazards have already taken place in the area...from geological materials (sands, dead and/or bleached corals ...etc) shifted by waves, tides, and currents moving sediments and eroding shorelines

Protecting the forests while allowing removal of damaged trees may imperil saproxylic insect biodiversity in the Hyrcanian Beech Forests of Iran

Treesearch

Müller Jörg; Thorn Simon; Baier Roland; Sagheb-Talebi Khosro; Barimani Hassan V.; Seibold Sebastian; Michael D. Ulyshen; Gossner Martin M.

2015-01-01

The 1.8 million ha of forest south of the Caspian Sea represent a remarkably intact ecosystem with numerous old-growth features and unique species assemblages. To protect these forests, Iranian authorities recently passed a law which protects healthy trees but permits the removal of injured, dying and dead trees. To quantify the biodiversity effects of this strategy,...

Bromine

USGS Publications Warehouse

Ober, J.A.

2013-01-01

The element bromine is found principally as a dissolved species in seawater, evaporitic (salt) lakes and underground brines associated with petroleum deposits. Seawater contains about 65 parts per million of bromine or an estimated 907 Gt (100 trillion st). In the Middle East, the highly saline waters of the Dead Sea are estimated to contain 907 Mt (1 billion st) of bromine. Bromine also may be recovered from seawater as a coproduct during evaporation to produce salt.

Electron microscope evidence of virus infection in cultured marine fish

NASA Astrophysics Data System (ADS)

Sun, Xiu-Qin; Zhang, Jin-Xing; Qu, Ling-Yun

2000-09-01

Electron microscope investigation on the red sea bream ( Pagrosomus major), bastard halibut ( Paralichthys olivaceus) and stone flounder ( Kareius bicoloratus) in North China revealed virus infection in the bodies of the dead and diseased fish. These viruses included the lymphocystis disease virus (LDV), parvovirus, globular virus, and a kind of baculavirus which was not discovered and reported before and is now tentatively named baculavirus of stone flounder ( Kareius bicoloratus).

The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation

PubMed Central

Cózar, Andrés; Martí, Elisa; Duarte, Carlos M.; García-de-Lomas, Juan; van Sebille, Erik; Ballatore, Thomas J.; Eguíluz, Victor M.; González-Gordillo, J. Ignacio; Pedrotti, Maria L.; Echevarría, Fidel; Troublè, Romain; Irigoien, Xabier

2017-01-01

The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris. PMID:28439534

The Arctic Ocean as a dead end for floating plastics in the North Atlantic branch of the Thermohaline Circulation.

PubMed

Cózar, Andrés; Martí, Elisa; Duarte, Carlos M; García-de-Lomas, Juan; van Sebille, Erik; Ballatore, Thomas J; Eguíluz, Victor M; González-Gordillo, J Ignacio; Pedrotti, Maria L; Echevarría, Fidel; Troublè, Romain; Irigoien, Xabier

2017-04-01

The subtropical ocean gyres are recognized as great marine accummulation zones of floating plastic debris; however, the possibility of plastic accumulation at polar latitudes has been overlooked because of the lack of nearby pollution sources. In the present study, the Arctic Ocean was extensively sampled for floating plastic debris from the Tara Oceans circumpolar expedition. Although plastic debris was scarce or absent in most of the Arctic waters, it reached high concentrations (hundreds of thousands of pieces per square kilometer) in the northernmost and easternmost areas of the Greenland and Barents seas. The fragmentation and typology of the plastic suggested an abundant presence of aged debris that originated from distant sources. This hypothesis was corroborated by the relatively high ratios of marine surface plastic to local pollution sources. Surface circulation models and field data showed that the poleward branch of the Thermohaline Circulation transfers floating debris from the North Atlantic to the Greenland and Barents seas, which would be a dead end for this plastic conveyor belt. Given the limited surface transport of the plastic that accumulated here and the mechanisms acting for the downward transport, the seafloor beneath this Arctic sector is hypothesized as an important sink of plastic debris.

Bacillus marismortui sp. nov., a new moderately halophilic species from the Dead Sea.

PubMed

Arahal, D R; Márquez, M C; Volcani, B E; Schleifer, K H; Ventosa, A

1999-04-01

A group of 91 moderately halophilic, Gram-positive, rod-shaped strains were isolated from enrichments prepared from Dead Sea water samples collected 57 years ago. These strains were examined for 117 morphological, physiological, biochemical, nutritional and antibiotic susceptibility characteristics. All strains formed endospores and were motile, strictly aerobic and positive for catalase and oxidase. They grew in media containing 5-25% (w/v) total salts, showing optimal growth at 10% (w/v). Eighteen strains were chosen as representative isolates and were studied in more detail. All these strains had mesodiaminopimelic acid in the cell wall and a DNA G + C content of 39.0-42.8 mol%; they constitute a group with levels of DNA-DNA similarity of 70-100%. The sequences of the 16S rRNA genes of three representative strains (strains 123T, 557 and 832) were almost identical (99.9%), and placed the strains in the low G + C content Gram-positive bacteria. On the basis of their features, these isolates should be regarded as members of a new species of the genus Bacillus, for which the name Bacillus marismortui sp. nov. is proposed. The type strain is strain 123T (= DSM 12325T = ATCC 700626T = CIP 105609T = CECT 5066T).

Observations in 2001 on hookworms ( Uncinaria spp.) in otariid pinnipeds.

PubMed

Lyons, E T; DeLong, R L; Spraker, T R; Melin, S R; Tolliver, S C

2003-04-01

Uncinaria spp. were recovered from the milk of California sea lions ( Zalophus californianus) collected from the: (1) teats of a cow just after parturition (one parasitic third-stage larva, L(3)), (2) stomach of her nursing pup (two L(3)), and (3) stomach of a dead pup about 2 days old (one L(3), one headless, probably L(3), and four L(4)) on San Miguel Island, California in May 2001. This, in addition to earlier research, indicates transmammary transmission of hookworms in this host. Uncinaria spp. were found in dead northern fur seals ( Callorhinus ursinus) in the: (1) intestines of 2 of 75 pups (either one or two adult specimens in each infected pup) and (2) ventral abdominal blubber of 3 of 78 subadult males (one to seven L(3) in each infected seal) on St. Paul Island (SPI), Alaska in July and August 2001. These findings verify the low current prevalence of Uncinariaspp. in fur seals on SPI. Rectal fecal samples taken from 50 live Steller sea lion ( Eumetopias jubatus) pups, about 1 month old, on Rogue Reef in Curry County, Oregon in July 2001, were all negative for the eggs of Uncinaria spp. The apparent zero infection rate in these pups is possibly because the rocky terrain of this rookery is not suitable for hookworm transmission.

Mapping and predicting sinkholes by integration of remote sensing and spectroscopy methods

NASA Astrophysics Data System (ADS)

Goldshleger, N.; Basson, U.; Azaria, I.

2013-08-01

The Dead Sea coastal area is exposed to the destructive process of sinkhole collapse. The increase in sinkhole activity in the last two decades has been substantial, resulting from the continuous decrease in the Dead Sea's level, with more than 1,000 sinkholes developing as a result of upper layer collapse. Large sinkholes can reach 25 m in diameter. They are concentrated mainly in clusters in several dozens of sites with different characteristics. In this research, methods for mapping, monitoring and predicting sinkholes were developed using active and passive remote-sensing methods: field spectrometer, geophysical ground penetration radar (GPR) and a frequency domain electromagnetic instrument (FDEM). The research was conducted in three stages: 1) literature review and data collection; 2) mapping regions abundant with sinkholes in various stages and regions vulnerable to sinkholes; 3) analyzing the data and translating it into cognitive and accessible scientific information. Field spectrometry enabled a comparison between the spectral signatures of soil samples collected near active or progressing sinkholes, and those collected in regions with no visual sign of sinkhole occurrence. FDEM and GPR investigations showed that electrical conductivity and soil moisture are higher in regions affected by sinkholes. Measurements taken at different time points over several seasons allowed monitoring the progress of an 'embryonic' sinkhole.

Clastic dikes of the Hatrurim basin (western flank of the Dead Sea) as natural analogues of alkaline concretes: Mineralogy, solution chemistry, and durability

NASA Astrophysics Data System (ADS)

Sokol, E. V.; Gaskova, O. L.; Kozmenko, O. A.; Kokh, S. N.; Vapnik, E. A.; Novikova, S. A.; Nigmatulina, E. N.

2014-11-01

This study shows that the mineral assemblages from clastic dikes in areas adjacent to the Dead Sea graben may be considered as natural analogues of alkaline concretes. The main infilling material of the clastic dikes is composed of well-sorted and well-rounded quartz sand. The cement of these hard rocks contains hydroxylapophyllite, tacharanite, calcium silicate hydrates, opal, calcite, and zeolite-like phases, which is indicative of a similarity of the natural cementation processes and industrial alkaline concrete production from quartz sands and industrial alkaline cements. The quartz grains exhibit a variety of reaction textures reflecting the interaction with alkaline solutions (opal and calcium hydrosilicate overgrowths; full replacement with apophyllite or thomsonite + apophyllite). The physicochemical analysis and reconstruction of the chemical composition of peralkaline Ca, Na, and K solutions that formed these assemblages reveal that the solutions evolved toward a more stable composition of zeolite-like phases, which are more resistant to long-term chemical weathering and atmospheric corrosion. The 40Ar/39Ar age of 6.2 ± 0.7 Ma obtained for apophyllite provides conclusive evidence for the high corrosion resistance of the assemblages consisting of apophyllite and zeolite-like phases.

Sea lamprey mark type, wounding rate, and parasite-host preference and abundance relationships for lake trout and other species in Lake Ontario

USGS Publications Warehouse

Lantry, Brian F.; Adams, Jean; Christie, Gavin; Schaner, Teodore; Bowlby, James; Keir, Michael; Lantry, Jana; Sullivan, Paul; Bishop, Daniel; Treska, Ted; Morrison, Bruce

2015-01-01

We examined how attack frequency by sea lampreys on fishes in Lake Ontario varied in response to sea lamprey abundance and preferred host abundance (lake trout > 433 mm). For this analysis we used two gill net assessment surveys, one angler creel survey, three salmonid spawning run datasets, one adult sea lamprey assessment, and a bottom trawl assessment of dead lake trout. The frequency of fresh sea lamprey marks observed on lake trout from assessment surveys was strongly related to the frequency of sea lamprey attacks observed on salmon and trout from the creel survey and spawning migrations. Attack frequencies on all salmonids examined were related to the ratio between the abundances of adult sea lampreys and lake trout. Reanalysis of the susceptibility to sea lamprey attack for lake trout strains stocked into Lake Ontario reaffirmed that Lake Superior strain lake trout were among the most and Seneca Lake strain among the least susceptible and that Lewis Lake strain lake trout were even more susceptible than the Superior strain. Seasonal attack frequencies indicated that as the number of observed sea lamprey attacks decreased during June–September, the ratio of healing to fresh marks also decreased. Simulation of the ratios of healing to fresh marks indicated that increased lethality of attacks by growing sea lampreys contributed to the decline in the ratios and supported laboratory studies about wound healing duration.

Sea lamprey mark type, marking rate, and parasite-host relationships for lake trout and other species in Lake Ontario

USGS Publications Warehouse

Lantry, Brian F.; Adams, Jean V.; Christie, Gavin; Schaner, Teodore; Bowlby, James; Keir, Michael; Lantry, Jana; Sullivan, Paul; Bishop, Daniel; Treska, Ted; Morrison, Bruce

2015-01-01

We examined how attack frequency by sea lampreys on fishes in Lake Ontario varied in response to sea lamprey abundance and preferred host abundance (lake trout > 433 mm). For this analysis we used two gill net assessment surveys, one angler creel survey, three salmonid spawning run datasets, one adult sea lamprey assessment, and a bottom trawl assessment of dead lake trout. The frequency of fresh sea lamprey marks observed on lake trout from assessment surveys was strongly related to the frequency of sea lamprey attacks observed on salmon and trout from the creel survey and spawning migrations. Attack frequencies on all salmonids examined were related to the ratio between the abundances of adult sea lampreys and lake trout. Reanalysis of the susceptibility to sea lamprey attack for lake trout strains stocked into Lake Ontario reaffirmed that Lake Superior strain lake trout were among the most and Seneca Lake strain among the least susceptible and that Lewis Lake strain lake trout were even more susceptible than the Superior strain. Seasonal attack frequencies indicated that as the number of observed sea lamprey attacks decreased during June–September, the ratio of healing to fresh marks also decreased. Simulation of the ratios of healing to fresh marks indicated that increased lethality of attacks by growing sea lampreys contributed to the decline in the ratios and supported laboratory studies about wound healing duration.

MODIS Views the Middle-East

NASA Technical Reports Server (NTRS)

2002-01-01

To paraphrase English author T.H. White, borders are the one thing a man sees that a bird cannot see as it flies high overhead. For the 15th consecutive day, differences in ideology have sparked violence and tension in the middle-east as the rest of the world watches, concerned. This true-color image of the region was taken on September 10, 2000, by the MODerate-resolution Imaging Spectroradiometer (MODIS) flying aboard NASA's Terra spacecraft. The image shows the lands of Israel along the eastern shore of the Mediterranean Sea, with the countries of Jordan to the southeast and Syria to the Northeast. Jerusalem, labeled, is Israel's capital city and Aman, labeled, is the capital of Jordan. The region known as the West Bank lies between the two countries. Running from north to south, the Jordan River links the Sea of Galilee to the Dead Sea. Image courtesy Jacques Descloitres, MODIS Land Group, NASA GSFC

Status of the University of Rochester tandem upgrade

NASA Astrophysics Data System (ADS)

Cross, Clinton; Miller, Thomas

1986-05-01

The status of the University of Rochester tandem Van de Graaff accelerator upgrade is reviewed. The accelerator upgrade to 18 MV consists of extended tubes, shielded resistors, dead-section ion pumping, two rotating insulating power shaft systems to provide power to the dead sections and terminal, and a pelletron charging system to replace the charging belt. Control of many of the accelerator operating systems will be done by two IBM personal computers. The negative ion injector diffusion pump, isolation transformer, preacceleration high-voltage power supply, and high-voltage corona enclosure will all be replaced. Finally, the SF6 gas handling system will be improved with the addition of a second set of gas dryers and a larger recirculating pump.

Wavelet-based tracking of bacteria in unreconstructed off-axis holograms.

PubMed

Marin, Zach; Wallace, J Kent; Nadeau, Jay; Khalil, Andre

2018-03-01

We propose an automated wavelet-based method of tracking particles in unreconstructed off-axis holograms to provide rough estimates of the presence of motion and particle trajectories in digital holographic microscopy (DHM) time series. The wavelet transform modulus maxima segmentation method is adapted and tailored to extract Airy-like diffraction disks, which represent bacteria, from DHM time series. In this exploratory analysis, the method shows potential for estimating bacterial tracks in low-particle-density time series, based on a preliminary analysis of both living and dead Serratia marcescens, and for rapidly providing a single-bit answer to whether a sample chamber contains living or dead microbes or is empty. Copyright © 2017 Elsevier Inc. All rights reserved.

Aral Sea basin: a sea dies, a sea also rises.

PubMed

Glantz, Michael H

2007-06-01

The thesis of this article is quite different from many other theses of papers, books, and articles on the Aral Sea. It is meant to purposely highlight the reality of the situation in Central Asia: the Aral Sea that was once a thriving body of water is no more. That sea is dead. What does exist in its place are the Aral seas: there are in essence three bodies of water, one of which is being purposefully restored and its level is rising (the Little Aral), and two others which are still marginally connected, although they continue to decline in level (the Big Aral West and the Big Aral East). In 1960 the level of the sea was about 53 m above sea level. By 2006 the level had dropped by 23 m to 30 m above sea level. This was not a scenario generated by a computer model. It was a process of environmental degradation played out in real life in a matter of a few decades, primarily as a result of human activities. Despite wishes and words to the contrary, it will take a heroic global effort to save what remains of the Big Aral. It would also take a significant degree of sacrifice by people and governments in the region to restore the Big Aral to an acceptable level, given that the annual rate of flow reaching the Amudarya River delta is less than a 10th of what it was several decades ago. Conferring World Heritage status to the Aral Sea(s) could spark restoration efforts for the Big Aral.

Behavior associated with forced copulation of juvenile Pacific harbor seals (Phoca vitulina richardsi) by southern sea otters (Enhydra lutris nereis)

USGS Publications Warehouse

Harris, Heather S.; Oates, Stori C.; Staedler, Michelle M.; Tinker, M. Tim; Jessup, David A.; Harvey, James T.; Miller, Melissa A.

2010-01-01

Nineteen occurrences of interspecific sexual behavior between male southern sea otters (Enhydra lutris nereis) and juvenile Pacific harbor seals (Phoca vitulina richardsi) were reported in Monterey Bay, California, between 2000 and 2002. At least three different male sea otters were observed harassing, dragging, guarding, and copulating with harbor seals for up to 7 d postmortem. Carcasses of 15 juvenile harbor seals were recovered, and seven were necropsied in detail by a veterinary pathologist. Necropsy findings from two female sea otters that were recovered dead from male sea otters exhibiting similar behavior are also presented to facilitate a comparison of lesions. The most frequent lesions included superficial skin lacerations; hemorrhage around the nose, eyes, flippers, and perineum; and traumatic corneal erosions or ulcers. The harbor seals sustained severe genital trauma, ranging from vaginal perforation to vagino-cervical transection, and colorectal perforations as a result of penile penetration. One harbor seal developed severe pneumoperitoneum subsequent to vaginal perforation, which was also observed in both female sea otters and has been reported as a postcoital lesion in humans. This study represents the first description of lesions resulting from forced copulation of harbor seals by sea otters and is also the first report of pneu-moperitoneum secondary to forced copulation in a nonhuman animal. Possible explanations for this behavior are discussed in the context of sea otter biology and population demographics.

Transformation mechanism of amorphous calcium carbonate into calcite in the sea urchin larval spicule

PubMed Central

Politi, Yael; Metzler, Rebecca A.; Abrecht, Mike; Gilbert, Benjamin; Wilt, Fred H.; Sagi, Irit; Addadi, Lia; Weiner, Steve; Gilbert, P. U. P. A.

2008-01-01

Sea urchin larval spicules transform amorphous calcium carbonate (ACC) into calcite single crystals. The mechanism of transformation is enigmatic: the transforming spicule displays both amorphous and crystalline properties, with no defined crystallization front. Here, we use X-ray photoelectron emission spectromicroscopy with probing size of 40–200 nm. We resolve 3 distinct mineral phases: An initial short-lived, presumably hydrated ACC phase, followed by an intermediate transient form of ACC, and finally the biogenic crystalline calcite phase. The amorphous and crystalline phases are juxtaposed, often appearing in adjacent sites at a scale of tens of nanometers. We propose that the amorphous-crystal transformation propagates in a tortuous path through preexisting 40- to 100-nm amorphous units, via a secondary nucleation mechanism. PMID:18987314

SV40 T antigen alone drives karyotype instability that precedes neoplastic transformation of human diploid fibroblasts.

PubMed

Ray, F A; Peabody, D S; Cooper, J L; Cram, L S; Kraemer, P M

1990-01-01

To define the role of SV40 large T antigen in the transformation and immortalization of human cells, we have constructed a plasmid lacking most of the unique coding sequences of small t antigen as well as the SV40 origin of replication. The promoter for T antigen, which lies within the origin of replication, was deleted and replaced by the Rous sarcoma virus promoter. This minimal construct was co-electroporated into normal human fibroblasts of neonatal origin along with a plasmid containing the neomycin resistance gene (neo). Three G418-resistant, T antigen-positive clones were expanded and compared to three T antigen-positive clones that received the pSV3neo plasmid (capable of expressing large and small T proteins and having two origins of replication). Autonomous replication of plasmid DNA was observed in all three clones that received pSV3neo but not in any of the three origin minus clones. Immediately after clonal expansion, several parameters of neoplastic transformation were assayed. Low percentages of cells in T antigen-positive populations were anchorage independent or capable of forming colonies in 1% fetal bovine serum. The T antigen-positive clones generally exhibited an extended lifespan in culture but rarely became immortalized. Large numbers of dead cells were continually generated in all T antigen-positive, pre-crisis populations. Ninety-nine percent of all T antigen-positive cells had numerical or structural chromosome aberrations. Control cells that received the neo gene did not have an extended life span, did not have noticeable numbers of dead cells, and did not exhibit karyotype instability. We suggest that the role of T antigen protein in the transformation process is to generate genetic hypervariability, leading to various consequences including neoplastic transformation and cell death.

Telemetry narrows the search for sea lamprey spawning locations in the St. Clair-Detroit River System

USGS Publications Warehouse

Holbrook, Christopher; Jubar, Aaron K.; Barber, Jessica M.; Tallon, Kevin; Hondorp, Darryl W.

2016-01-01

Adult sea lamprey (Petromyzon marinus) abundance in Lake Erie has remained above targets set by fishery managers since 2005, possibly due to increased recruitment in the St. Clair-Detroit River System (SCDRS). Sea lamprey recruitment in the SCDRS poses an enormous challenge to sea lamprey control and assessment in Lake Erie because the SCDRS contains no dams to facilitate capture and discharge is at least an order of magnitude larger in the SCDRS than most other sea lamprey-producing tributaries in the Great Lakes. As a first step toward understanding population size, spatial distribution, and spawning habitat of adult sea lampreys in the SCDRS, we used acoustic telemetry to determine where sea lampreys ceased migration (due to spawning, death, or both) among major regions of the SCDRS. All tagged sea lampreys released in the lower Detroit River (N = 27) moved upstream through the Detroit River and entered Lake St. Clair. After entering Lake St. Clair, sea lampreys entered the St. Clair River (N = 22), Thames River (N = 1), or were not detected again (N = 4). Many sea lampreys (10 of 27) were last observed moving downstream (“fallback”) but we were unable to determine if those movements occurred before or after spawning, or while sea lampreys were dead or alive. Regardless of whether estimates of locations where sea lampreys ceased migration were based on the most upstream region occupied or final region occupied, most sea lampreys ceased migration in the St. Clair River or Lake St. Clair. Results suggest that spawning and rearing in the St. Clair River could be an important determinant of sea lamprey recruitment in the SCDRS and may direct future assessment and control activities in that system.

Limacina retroversa's response to combined effects of ocean acidification and sea water freshening

NASA Astrophysics Data System (ADS)

Manno, C.; Morata, N.; Primicerio, R.

2012-11-01

Anthropogenic carbon dioxide emissions induce ocean acidification, thereby reducing carbonate ion concentration, which may affect the ability of calcifying organisms to build shells. Pteropods, the main planktonic producers of aragonite in the worlds' oceans, may be particularly vulnerable to changes in sea water chemistry. The negative effects are expected to be most severe at high-latitudes, where natural carbonate ion concentrations are low. In this study we investigated the combined effects of ocean acidification and freshening on Limacina retroversa, the dominant pteropod in sub polar areas. Living L. retroversa, collected in Northern Norwegian Sea, were exposed to four different pH values ranging from the pre-industrial level to the forecasted end of century ocean acidification scenario. Since over the past half-century the Norwegian Sea has experienced a progressive freshening with time, each pH level was combined with a salinity gradient in two factorial, randomized experiments investigating shell degradation, swimming behavior and survival. In addition, to investigate shell degradation without any physiologic influence, one perturbation experiments using only shells of dead pteropods was performed. Lower pH reduced shell mass whereas shell dissolution increased with pCO2. Interestingly, shells of dead organisms had a higher degree of dissolution than shells of living individuals. Mortality of Limacina retroversa was strongly affected only when both pH and salinity reduced simultaneously. The combined effects of lower salinity and lower pH also affected negatively the ability of pteropods to swim upwards. Results suggest that the energy cost of maintaining ion balance and avoiding sinking (in low salinity scenario) combined with the extra energy cost necessary to counteract shell dissolution (in high pCO2 scenario), exceed the available energy budget of this organism causing the pteropods to change swimming behavior and begin to collapse. Since L. retroversa play an important role in the transport of carbonates to the deep oceans these findings have significant implications for the mechanisms influencing the inorganic carbon cycle in the sub-polar area.

Assessing environmental impact from gas and oil exploration in the SW Barents Sea using benthic foraminiferal assemblages

NASA Astrophysics Data System (ADS)

Dijkstra, N.; Junttila, J.; Husum, K.; Carroll, J.; Hald, M.

2012-04-01

During the last decades petroleum industry and shipping activities have increased in the SW Barents Sea. Oil exploration wells were drilled in the 1980s with production starting in 2007. These activities are projected to expand in the coming years. As part of the Northern Environmental Waste Management (EWMA) project, a competence cluster for petroleum industry related waste handling, we investigate the impacts of enhanced anthropogenic activities on benthic foraminiferal assemblages in the SW Barents Sea. Sediment cores (0-20 cm) from sites in proximity to two oil- and gas fields are under investigation. These sediment cores, dated with the 210Pb method, represent the last 90 to 150 years. Both dead and living benthic foraminifera (100 µm-1 mm) were counted to elucidate differences in foraminiferal assemblages between pre-impact and recent conditions. In addition, the heavy metal concentrations, persistent organic pollutant (POP) concentrations, grain size and total organic content (TOC) of the sediment cores have been analyzed. Pollution levels of the surface sediments (0-1 cm) are of background to good level (level I-II) according to the definitions of the Water Framework Directorate (WFD). Patterns in living benthic foraminiferal assemblages identified in the sea floor surface sediments, are the result of natural environmental changes such as depth, water mass and sediment composition. Further downcore (1-20 cm) pollution levels are in general of background environmental status (WFD level I). However, at some depth intervals, especially in sediment cores from the near proximity of the oil- and gas- fields, pollution levels are slightly enhanced (WFD level II). Further work will include statistical comparison of dead and living foraminiferal assemblages with sediment pollution levels, sediment properties, and oceanographic conditions. This research contributes to the development of foraminifera as a useful bio-monitoring technique for the Arctic region as industrial activities increase in the coming years.

Differentiation of live and dead salmonella cells using fourier transform infrared (FTIR) spectroscopy and principle component analysis (PCA) technique

USDA-ARS?s Scientific Manuscript database

Various technologies have been developed for pathogen detection using optical, electrochemical, biochemical and physical properties. Conventional microbiological methods need time from days to week to get the result. Though this method is very sensitive and accurate, a rapid detection of pathogens i...

Geoid undulations and gravity anomalies over the Aral Sea, the Black Sea and the Caspian Sea from a combined GEOS-3/SEASAT/GEOSAT altimeter data set

NASA Technical Reports Server (NTRS)

Au, Andrew Y.; Brown, Richard D.; Welker, Jean E.

1991-01-01

Satellite-based altimetric data taken by GOES-3, SEASAT, and GEOSAT over the Aral Sea, the Black Sea, and the Caspian Sea are analyzed and a least squares collocation technique is used to predict the geoid undulations on a 0.25x0.25 deg. grid and to transform these geoid undulations to free air gravity anomalies. Rapp's 180x180 geopotential model is used as the reference surface for the collocation procedure. The result of geoid to gravity transformation is, however, sensitive to the information content of the reference geopotential model used. For example, considerable detailed surface gravity data were incorporated into the reference model over the Black Sea, resulting in a reference model with significant information content at short wavelengths. Thus, estimation of short wavelength gravity anomalies from gridded geoid heights is generally reliable over regions such as the Black Sea, using the conventional collocation technique with local empirical covariance functions. Over regions such as the Caspian Sea, where detailed surface data are generally not incorporated into the reference model, unconventional techniques are needed to obtain reliable gravity anomalies. Based on the predicted gravity anomalies over these inland seas, speculative tectonic structures are identified and geophysical processes are inferred.

Evolution of the Andaman Sea region: Dextral transtension as consequence of the India-Asia collision

NASA Astrophysics Data System (ADS)

Zhang, L.; Xu, J.; Ben-Avraham, Z.; Kelty, T. K.

2010-12-01

The two gigantic conjugate strike-slip faults: the Altyn Fault and the Sagaing Fault in northwest and southeast of the proto-Tibet plateau respectively, began to form as consequence of initiation of the India-Asia collision at around 50 Ma (Xu, 2005; Xu et al., 2010). The Sagaing Fault, Andaman trench fault as well as the Sumatra Fault controlled the evolution of the Andaman Sea region while the collision proceeded. By synthesis of geometry and rifting history of the Andaman Sea Basin and Mergui Basin and the plate tectonic setting, we suggest the following five-stage evolution model for the Andaman Sea region: (1) dextral pull-apart rifting and seafloor spreading from 50 Ma to 32 Ma; (2) dextral transform margin-type rifting was active in Mergui Basin with principal fault being the Sumatran Fault system, and both the transform margin-type rifting and the dextral pull-apart rifting were coevally active in the Andaman Sea Basin during 32 Ma to 20 Ma, when the Sumatra fault rotated CW enough and obliquity of subduction of the Indian plate motion along the Sumatra trench was enough to trigger the dextral displacement to take place on the Sumatra Fault system and the Mottawi fault; (3) the Alcock and Sewell plateaus formed in the Andaman Sea by the NNW transtension and the transform margin-type rifting continued in the Mergui basin during 20 Ma to 15 Ma; (4) NNW weak transtensional rifting on the Alcock and Sewell plateaus and NW weak transform margin-type rifting continued in the Mergui basin during 15 Ma to 5 Ma; (5)transtensional rifting similar with but more intensive than earlier stage kept on, forming the central Andaman Basin and the East basin, from 5 Ma to present.

Snow and Dust over Inner Mongolia

NASA Technical Reports Server (NTRS)

2002-01-01

A severe snow-and-sand storm hit an 80,000 square-mile (205,000-square-km) stretch of the Chinese province of Mongolia on New Year's Eve, killing 21 people and leaving thousands of people to face possible starvation. The affected area is located about 250 miles (400 km) northwest of Beijing. It is the worst snowstorm to hit the region in more than 50 years. Lasting about 3 days, the storm dumped 24 inches (60 cm) of snow mixed with sand from the Gobi Desert, stranding many residents in deep drifts. The Chinese Red Cross reports that almost 1 million people were affected by the storm and at least 10,000 head of livestock are confirmed dead. As many as 120,000 residents are in need of food and other supplies. The Sea-viewing Wide Field-of-view Sensor (SeaWiFS), flying aboard the OrbView-2 satellite, acquired this image of the storm on January 2, 2001, as it approached China's eastern provinces. You can see storm clouds (white pixels) and windblown dust (brownish pixels) crossing the Yellow Sea and East China Sea toward Japan and the western Pacific. Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

Digenetic trematodes in South American sea lions from southern Brazilian waters.

PubMed

Pereira, E M; Müller, G; Secchi, E; Pereira, J; Valente, A L S

2013-10-01

The aim of this work was to perform a systematic study to detect and quantify the digenetic trematode infections in South American sea lions from the southern Brazilian coast. Twenty-four South American sea lions, Otaria flavescens (Carnivora: Otaridae), were found dead along the coast of Rio Grande do Sul State, Brazil, between June 2010 and September of 2011. Two trematode species were found in the intestines of O. flavescens, i.e., Stephanoprora uruguayense (Digenea: Echinostomatidae) and Ascocotyle (Phagicola) longa (Digenea: Heterophyidae). Ascocotyle (P.) longa reached a prevalence of 33.3% and mean intensity of 248,500, whereas S. uruguayense showed a prevalence of 4.2% and mean intensity of 202. The 2 trematode species infecting sea lions were likely transmitted by feeding on mullets, Mugil platanus, that commonly harbor heterophyid metacercariae. The present work is the first report of digenetic trematodes infecting O. flavescens in Brazil. The high prevalence and mean intensity values of the 2 trematode species infecting sea lions in the present study suggest caution in human consumption of mullets and other fish, which can be infected with the metacercariae of these trematodes known to have zoonotic potential.

[Dangerous marine animals].

PubMed

Antensteiner, G

1999-01-01

Sea-biological basic knowledge for divers is offered only in special lessons for advanced scuba divers. According to statistics, however, five per cent of the deadly diving accidents are caused by underwater organisms. This number could be reduced to a fraction, by correct behaviour during the dive and after an accident. The most frequent accidents with sea animals during water sports are not by unprovoked shark attacks, which cause six deaths world-wide per year on the average, but turn out with usually well camouflaged sea inhabitants, that do not attack humans, rather by their inadvertence coincidentally get in contact with it. The various defense instruments of the often small, inconspicuous organisms reach from teeth over poison stings, pricks, spines, scalpelles, nettle injections and chemical weapons up to poison arrows. Due to that variety of the maritime life, the most important representatives of its type are explained including severity level of the caused injury or contamination. Both, diagnostic position and therapy possibility are described as follows: 1. Porifera (sponge), 2. Hydrozoa (white weed, yellow flower head), Actinaria (sea anemones), 3. Conidae (cone shells), Tridocna (giant clam), octopoda (octopus), 4. Acanthaster planci (crown of thorns), Echinodea (sea urchins), Holothurioidea (sea cucumber), 5. Selachoidei (shark), Batoidei (Ray), Muraenidae (moray), Plotosidae (barbel eels), Synanciidae (stonefish), Scorpaenidae (scorpionfish), Pterois (lion fish), Sphyraena Spec. (barracuda), Balistidae (triggerfish), Ostracionidae (puffer).

Microplastic pollution in sediments from the Bohai Sea and the Yellow Sea, China.

PubMed

Zhao, Jianmin; Ran, Wen; Teng, Jia; Liu, Yongliang; Liu, Hui; Yin, Xiaonan; Cao, Ruiwen; Wang, Qing

2018-06-02

Microplastics are one of the most significant pollutants in the marine environment and accumulate in sediments all over the world. To assess the pollution level in the marine environment in China, the distribution and abundance of microplastics in sediments from the Bohai Sea and the Yellow Sea were investigated in this study. The sediment samples were collected from 72 different sites in the Bohai Sea and the Yellow Sea. Microplastics were separated from sediment through density flotation and categorized according to shape and size under a microscope. Additionally, polymer types were identified using Fourier-Transform Infrared Micro-spectroscopy (μ-FT-IR). Our study demonstrated that microplastics were consistently found in all samples, which emphasized their extensive distribution throughout the Bohai Sea and the Yellow Sea. The average microplastic abundance was 171.8, 123.6 and 72.0 items per kg of dry weight sediment for the Bohai Sea, Northern Yellow Sea and Southern Yellow Sea, respectively. Among the sampled microplastics, fiber (93.88%) and small microplastics (<1000 μm) (71.06%) were the most frequent types. Fourier transform infrared microspectroscopy (μ-FT-IR) analysis determined that the main types of microplastics were rayon (RY), polyethylene (PE) and polyethylene terephthalate (PET). Our results highlighted the widespread distribution of microplastics in sediments from the Bohai Sea and the Yellow Sea and provided useful information for evaluating the environmental risks of microplastics in China. Copyright © 2018. Published by Elsevier B.V.

Neural-adaptive control of single-master-multiple-slaves teleoperation for coordinated multiple mobile manipulators with time-varying communication delays and input uncertainties.

PubMed

Li, Zhijun; Su, Chun-Yi

2013-09-01

In this paper, adaptive neural network control is investigated for single-master-multiple-slaves teleoperation in consideration of time delays and input dead-zone uncertainties for multiple mobile manipulators carrying a common object in a cooperative manner. Firstly, concise dynamics of teleoperation systems consisting of a single master robot, multiple coordinated slave robots, and the object are developed in the task space. To handle asymmetric time-varying delays in communication channels and unknown asymmetric input dead zones, the nonlinear dynamics of the teleoperation system are transformed into two subsystems through feedback linearization: local master or slave dynamics including the unknown input dead zones and delayed dynamics for the purpose of synchronization. Then, a model reference neural network control strategy based on linear matrix inequalities (LMI) and adaptive techniques is proposed. The developed control approach ensures that the defined tracking errors converge to zero whereas the coordination internal force errors remain bounded and can be made arbitrarily small. Throughout this paper, stability analysis is performed via explicit Lyapunov techniques under specific LMI conditions. The proposed adaptive neural network control scheme is robust against motion disturbances, parametric uncertainties, time-varying delays, and input dead zones, which is validated by simulation studies.

No place, new places: death and its rituals in urban Asia.

PubMed

Kong, Lily

2012-01-01

In many land-scarce Asian cities, planning agencies have sought to reduce space for the dead to release land for the living, encouraging conversion from burial to cremation over several decades. This has caused secular principles privileging efficient land use to conflict with symbolic values invested in burial spaces. Over time, not only has cremation become more accepted, even columbaria have become overcrowded, and new forms of burials (sea and woodland burials) have emerged. As burial methods change, so too do commemorative rituals, including new on-line and mobile phone rituals. This paper traces the ways in which physical spaces for the dead in several east Asian cities have diminished and changed over time, the growth of virtual space for them, the accompanying discourses that influence these dynamics and the new rituals that emerge concomitantly with the contraction of land space.

Student Projects that Make a Meaningful and Lasting Contribution to Course Content

ERIC Educational Resources Information Center

Schmidt, Shelly J.

2013-01-01

The objective of this teaching tip is to share with others an idea of how to transform student projects from a dead-end process to a value-added end product, value-added end products that make a meaningful and lasting contribution to course content for use by future students. (Contains 2 tables.)

Flow and transport within a coastal aquifer adjacent to a stratified water body

NASA Astrophysics Data System (ADS)

Oz, Imri; Yechieli, Yoseph; Eyal, Shalev; Gavrieli, Ittai; Gvirtzman, Haim

2016-04-01

The existence of a freshwater-saltwater interface and the circulation flow of saltwater beneath the interface is a well-known phenomenon found at coastal aquifers. This flow is a natural phenomenon that occurs due to density differences between fresh groundwater and the saltwater body. The goals of this research are to use analytical, numerical, and physical models in order to examine the configuration of the freshwater-saltwater interface and the density-driven flow patterns within a coastal aquifer adjacent to long-term stratified saltwater bodies (e.g. meromictic lake). Such hydrological systems are unique, as they consist of three different water types: the regional fresh groundwater, and low and high salinity brines forming the upper and lower water layers of the stratified water body, respectively. This research also aims to examine the influence of such stratification on hydrogeological processes within the coastal aquifer. The coastal aquifer adjacent to the Dead Sea, under its possible future meromictic conditions, serves as an ideal example to examine these processes. The results show that adjacent to a stratified saltwater body three interfaces between three different water bodies are formed, and that a complex flow system, controlled by the density differences, is created, where three circulation cells are developed. These results are significantly different from the classic circulation cell that is found adjacent to non-stratified water bodies (lakes or oceans). In order to obtain a more generalized insight into the groundwater behavior adjacent to a stratified water body, we used the numerical model to perform sensitivity analysis. The hydrological system was found be sensitive to three dimensionless parameters: dimensionless density (i.e. the relative density of the three water bodies'); dimensionless thickness (i.e. the ratio between the relative thickness of the upper layer and the whole thickness of the lake); and dimensionless flux. The results also show that this configuration of three interfaces and three circulation cells, which is expected to develop adjacent to the stratified Dead Sea, is expected to decrease the dissolution rates of salt layer that is located within the adjacent aquifer, by one order of magnitude in comparison to the dissolution rates today. Therefore, the processes of salt dissolution and sinkhole formation adjacent to the Dead Sea will be relatively restrained.

First report of systemic toxoplasmosis in a New Zealand sea lion (Phocarctos hookeri).

PubMed

Roe, W D; Michael, S; Fyfe, J; Burrows, E; Hunter, S A; Howe, L

2017-01-01

A 1-year-old female New Zealand sea lion (Phocarctos hookeri) was intermittently observed in the Otago region of New Zealand over an 11-month period, always dragging her hind flippers. In December 2012 the sea lion was found dead, after a period of several days being observed to be harassed by male sea lions. At gross postmortem examination the sea lion was in moderate body condition with signs of recent bite wounds and bruising. The lungs were dark and poorly inflated. Histological findings included meningoencephalomyelitis, radiculomyelitis of the cauda equina, myocarditis and myositis. Toxoplasmosis gondii organisms were detected histologically and following immunohistochemistry in the brain, spinal cord, spinal nerves and pelvic muscles. Nested PCR analysis and sequencing confirmed the presence of T. gondii DNA in uterine and lung tissue. A variant type II T. gondii genotype was identified using multilocus PCR-restriction fragment length polymorphism analysis. Systemic toxoplasmosis. Infection with T. gondii involving the spinal cord and nerves was the likely cause of the paresis observed in this sea lion before death. Ultimately, death was attributed to crushing and asphyxiation by a male sea lion, presumably predisposed by impaired mobility. Diagnosis of toxoplasmosis in a New Zealand sea lion highlights the possibility that this disease could play a role in morbidity and mortality in this endangered species, particularly in the recently established mainland populations that are close to feline sources of T. gondii oocysts.

Lesions and behavior associated with forced copulation of juvenile Pacific harbor seals (Phoca vitulina richardsi) by southern sea otters (Enhydra lutris nereis)

USGS Publications Warehouse

Harris, H.S.; Oates, S.C.; Staedler, M.M.; Tinker, M.T.; Jessup, David A.; Harvey, J.T.; Miller, M.A.

2010-01-01

Nineteen occurrences of interspecific sexual behavior between male southern sea otters (Enhydra lutris nereis) and juvenile Pacific harbor seals (Phoca vitulina richardsi) were reported in Monterey Bay, California, between 2000 and 2002. At least three different male sea otters were observed harassing, dragging, guarding, and copulating with harbor seals for up to 7 d postmortem. Carcasses of 15 juvenile harbor seals were recovered, and seven were necropsied in detail by a veterinary pathologist. Necropsy findings from two female sea otters that were recovered dead from male sea otters exhibiting similar behavior are also presented to facilitate a comparison of lesions. The most frequent lesions included superficial skin lacerations; hemorrhage around the nose, eyes, flippers, and perineum; and traumatic corneal erosions or ulcers. The harbor seals sustained severe genital trauma, ranging from vaginal perforation to vagino-cervical transection, and colorectal perforations as a result of penile penetration. One harbor seal developed severe pneumoperitoneum subsequent to vaginal perforation, which was also observed in both female sea otters and has been reported as a postcoital lesion in humans. This study represents the first description of lesions resulting from forced copulation of harbor seals by sea otters and is also the first report of pneumoperitoneum secondary to forced copulation in a nonhuman animal. Possible explanations for this behavior are discussed in the context of sea otter biology and population demographics.

46 CFR 111.20-1 - General requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-1 General requirements. Each transformer winding must be resistant to moisture, sea atmosphere, and oil vapor, unless special precautions...

46 CFR 111.20-1 - General requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-1 General requirements. Each transformer winding must be resistant to moisture, sea atmosphere, and oil vapor, unless special precautions...

46 CFR 111.20-1 - General requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-1 General requirements. Each transformer winding must be resistant to moisture, sea atmosphere, and oil vapor, unless special precautions...

46 CFR 111.20-1 - General requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-1 General requirements. Each transformer winding must be resistant to moisture, sea atmosphere, and oil vapor, unless special precautions...

46 CFR 111.20-1 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... REQUIREMENTS Transformer Construction, Installation, and Protection § 111.20-1 General requirements. Each transformer winding must be resistant to moisture, sea atmosphere, and oil vapor, unless special precautions...

Study of Pure Proteins, Nucleic Acids and their Complexes from Extreme Halobacteria of the Dead Sea: RNA Polymerase-DNA Interaction

DTIC Science & Technology

1988-10-10

identify by block number) FIELD GROUP S OUP - Archaebacteria , Halobacteria, Proteins Nucleic Acids, 08 RNA Polymerase-DNA Interactionsi R soimal operons...objectives of our program are to isolate and characterize a fully active DNA dependent RNA polymerase from the extremely halophilic archaebacteria from...Woese and his colleagues to suggest that all living organisms can be classified into three phylogenetic kingdoms : the eukaryotes, the eubacterla and

Ground Truth, Magnitude Calibration and Regional Phase Propagation and Detection in the Middle East and Horn of Africa

DTIC Science & Technology

2007-09-01

consists of late Proterozoic crystalline basement overlain by Tertiary and Quaternary volcanic rocks in some places. The breakup of the Arabian Plate from...with structure directly below the crust. To investigate upper mantle structure under the Arabian Shield, measured and inverted relative travel times...Plateau, Zagros Mountains, Arabian Peninsula, Turkish Plateau, Gulf of Aqaba, Dead Sea Rift) and the Horn of Africa (including the northern part of

Effect of formulation variables on the physical properties and stability of Dead Sea mud masks.

PubMed

Shahin, Sawsan; Hamed, Saja; Alkhatib, Hatim S

2015-01-01

The physical stability of Dead Sea mud mask formulations under different conditions and their rheological properties were evaluated as a function of the type and level of thickeners, level of the humectant, incorporation of ethanol, and mode of mud treatment. Formulations were evaluated in terms of visual appearance, pH, moisture content, spreadability, extrudability, separation, rate of drying at 32 degrees C, and rheological properties. Prepared mud formulations and over-the-shelf products showed viscoplastic shear thinning behavior; satisfactory rheological behavior was observed with formulations containing a total concentration of thickeners less than 10% (w/w). Casson and Herschel-Bulkley models were found the most suitable to describe the rheological data of the prepared formulations. Thickener incorporation decreased phase separation and improved formulation stability. Bentonite incorporation in the mud prevented color changes during stability studies while glycerin improved spreadability. Addition of 5% (w/w) ethanol improved mud extrudability, slightly increased percent separation, accelerated drying at 32 degrees C, and decreased viscosity and yield stress values. Different mud treatment techniques did not cause a clear behavioral change in the final mud preparation. B10G and K5B5G were labeled as "best formulas" based on having satisfactory physical and aesthetic criteria investigated in this study, while other formulations failed in one or more of the tests we have performed.

Intraplate Crustal Deformation Within the Northern Sinai Microplate: Evidence from Paleomagnetic Directions and Mechanical Modeling

NASA Astrophysics Data System (ADS)

Dembo, N.; Granot, R.; Hamiel, Y.

2017-12-01

The intraplate crustal deformation found in the northern part of the Sinai Microplate, located near the northern Dead Sea Fault plate boundary, is examined. Previous studies have suggested that distributed deformation in Lebanon is accommodated by regional uniform counterclockwise rigid block rotations. However, remanent magnetization directions observed near the Lebanese restraining bend are not entirely homogeneous suggesting that an unexplained and complex internal deformation pattern exists. In order to explain the variations in the amount of vertical-axis rotations we construct a mechanical model of the major active faults in the region that simulates the rotational deformation induced by motion along these faults. The rotational pattern calculated by the mechanical modeling predicts heterogeneous distribution of rotations around the faults. The combined rotation field that considers both the fault induced rotations and the already suggested regional block rotations stands in general agreement with the observed magnetization directions. Overall, the modeling results provide a more detailed and complete picture of the deformation pattern in this region and show that rotations induced by motion along the Dead Sea Fault act in parallel to rigid block rotations. Finally, the new modeling results unravel important insights as to the fashion in which crustal deformation is distributed within the northern part of the Sinai Microplate and propose an improved deformational mechanism that might be appropriate for other plate margins as well.

Effect of Water Surface Salinity on Evaporation: The Case of a Diluted Buoyant Plume Over the Dead Sea

NASA Astrophysics Data System (ADS)

Mor, Z.; Assouline, S.; Tanny, J.; Lensky, I. M.; Lensky, N. G.

2018-03-01

Evaporation from water bodies strongly depends on surface water salinity. Spatial variation of surface salinity of saline water bodies commonly occurs across diluted buoyant plumes fed by freshwater inflows. Although mainly studied at the pan evaporation scale, the effect of surface water salinity on evaporation has not yet been investigated by means of direct measurement at the scale of natural water bodies. The Dead Sea, a large hypersaline lake, is fed by onshore freshwater springs that form local diluted buoyant plumes, offering a unique opportunity to explore this effect. Surface heat fluxes, micrometeorological variables, and water temperature and salinity profiles were measured simultaneously and directly over the salty lake and over a region of diluted buoyant plume. Relatively close meteorological conditions prevailed in the two regions; however, surface water salinity was significantly different. Evaporation rate from the diluted plume was occasionally 3 times larger than that of the main salty lake. In the open lake, where salinity was uniform with depth, increased wind speed resulted in increased evaporation rate, as expected. However, in the buoyant plume where diluted brine floats over the hypersaline brine, wind speed above a threshold value (˜4 m s-1) caused a sharp decrease in evaporation probably due to mixing of the stratified plume and a consequent increase in the surface water salinity.

Variable slip-rate and slip-per-event on a plate boundary fault: The Dead Sea fault in northern Israel

NASA Astrophysics Data System (ADS)

Wechsler, Neta; Rockwell, Thomas K.; Klinger, Yann

2018-01-01

We resolved displacement on buried stream channels that record the past 3400 years of slip history for the Jordan Gorge (JGF) section of the Dead Sea fault in Israel. Based on three-dimensional (3D) trenching, slip in the past millennium amounts to only 2.7 m, similar to that determined in previous studies, whereas the previous millennium experienced two to three times this amount of displacement with nearly 8 m of cumulative slip, indicating substantial short term variations in slip rate. The slip rate averaged over the past 3400 years, as determined from 3D trenching, is 4.1 mm/yr, which agrees well with geodetic estimates of strain accumulation, as well as with longer-term geologic slip rate estimates. Our results indicate that: 1) the past 1200 years appear to significantly lack slip, which may portend a significant increase in future seismic activity; 2) short-term slip rates for the past two millennia have varied by more than a factor of two and suggest that past behavior is best characterized by clustering of earthquakes. From these observations, the earthquake behavior of the Jordan Gorge fault best fits is a "weak segment model" where the relatively short fault section (20 km), bounded by releasing steps, fails on its own in moderate earthquakes, or ruptures with adjacent segments.

Selenihalanaerobacter shriftii gen. nov., sp. nov., a halophilic anaerobe from Dead Sea sediments that respires selenate

USGS Publications Warehouse

Switzer, Blum J.; Stolz, J.F.; Oren, A.; Oremland, R.S.

2001-01-01

We isolated an obligately anaerobic halophilic bacterium from the Dead Sea that grew by respiration of selenate. The isolate, designated strain DSSe-1, was a gram-negative, non-motile rod. It oxidized glycerol or glucose to acetate+CO2 with concomitant reduction of selenate to selenite plus elemental selenium. Other electron acceptors that supported anaerobic growth on glycerol were nitrate and trimethylamine-N-oxide; nitrite, arsenate, fumarate, dimethylsulfoxide, thiosulfate, elemental sulfur, sulfite or sulfate could not serve as electron acceptors. Growth on glycerol in the presence of nitrate occurred over a salinity range from 100 to 240 g/l, with an optimum at 210 g/l. Analysis of the 16S rRNA gene sequence suggests that strain DSSe-1 belongs to the order Halanaerobiales, an order of halophilic anaerobes with a fermentative or homoacetogenic metabolism, in which anaerobic respiratory metabolism has never been documented. The highest 16S rRNA sequence similarity (90%) was found with Acetohalobium arabaticum (X89077). On the basis of physiological properties as well as the relatively low homology of 16S rRNA from strain DSSe-1 with known genera, classification in a new genus within the order Halanaerobiales, family Halobacteroidaceae is warranted. We propose the name Selenihalanaerobacter shriftii. Type strain is strain DSSe-1 (ATCC accession number BAA-73).

Natural outbreak of Streptococcus agalactiae (GBS) infection in wild giant Queensland grouper, Epinephelus lanceolatus (Bloch), and other wild fish in northern Queensland, Australia.

PubMed

Bowater, R O; Forbes-Faulkner, J; Anderson, I G; Condon, K; Robinson, B; Kong, F; Gilbert, G L; Reynolds, A; Hyland, S; McPherson, G; Brien, J O'; Blyde, D

2012-03-01

Ninety-three giant Queensland grouper, Epinephelus lanceolatus (Bloch), were found dead in Queensland, Australia, from 2007 to 2011. Most dead fish occurred in northern Queensland, with a peak of mortalities in Cairns in June 2008. In 2009, sick wild fish including giant sea catfish, Arius thalassinus (Rüppell), and javelin grunter, Pomadasys kaakan (Cuvier), also occurred in Cairns. In 2009 and 2010, two disease epizootics involving wild stingrays occurred at Sea World marine aquarium. Necropsy, histopathology, bacteriology and PCR determined that the cause of deaths of 12 giant Queensland grouper, three wild fish, six estuary rays, Dasyatis fluviorum (Ogilby), one mangrove whipray, Himantura granulata (Macleay), and one eastern shovelnose ray, Aptychotrema rostrata (Shaw), was Streptococcus agalactiae septicaemia. Biochemical testing of 34 S. agalactiae isolates from giant Queensland grouper, wild fish and stingrays showed all had identical biochemical profiles. The 16S rRNA gene sequences of isolates confirmed all isolates were S. agalactiae; genotyping of selected S. agalactiae isolates showed the isolates from giant Queensland grouper were serotype Ib, whereas isolates from wild fish and stingrays closely resembled serotype II. This is the first report of S. agalactiae from wild giant Queensland grouper and other wild tropical fish and stingray species in Queensland, Australia. © 2012 Blackwell Publishing Ltd and State of Queensland.

Earthquake bursts and fault branching: lessons from the Carmel fault branch (CFB) of the Dead Sea Transform (DST)

NASA Astrophysics Data System (ADS)

Agnon, A.; Rockwell, T. K.; Stein, S.; Raphael, K.

2017-12-01

The DST, accommodating most of the displacement across the boundary zone between the Arabian and Sinai plates, is an ideal plate boundary on which to study earthquake sequences because of 1) a long (>2 kyr) record of historical earthquakes (corroborated and extended several millennia back with ancient ruins); 2) deformed sediments and rockfalls, offering datable archives of strong shaking at various distances from the fault, spanning 300 kyr; 3) a moderate fault slip rate, allowing separation and dating of individual earthquakes for comparison to the historical record, and 4) a growing body of paleoseismic trench data on both timing and displacement across some sectors of the fault. Here we explore the role of a secondary fault branch on clustering using a new approach for the analysis of earthquake bursts. The CFZ is a ≥100 km long shear zone, branching northwestward from the N-S trending Jordan Valley segment of the DST. GPS monitoring of the CFZ indicates a slip rate of <1 mm/yr, absorbing up to 20% of the slip between Arabia Plate and the Sinai-Levant Block across the DST. CFZ seismicity is recorded by three datasets with different time scales and maximum magnitudes: 1) Instrumental seismicity, M≤5.3 (1984); 2) Historic documents suggesting a M>6 event in 363 CE, with ruins distributed up to 100 km from the CFZ; 3) 5 ka cave deposits showing damage greater than from any subsequent earthquake, implying 6The CFZ branch events interact with ruptures on the main DST. At 5 ka destruction was widespread along the DST. The 363 CE earthquake was accompanied by another event in the Arava Valley. The pair skipped the 100 km long Dead Sea segment of the DST. An earlier pair in the northern Levant preceded that pair by several decades: 303 & 347 CE, following a two-century long quiescence, and a harbinger for a shaky millennium. We suggest that the 363 CE pair reflects a rare state that enables a CFZ rupture. This oblique branch is unfavorably oriented for slip under the state of stress that drives the sinistral shear on the N-S DST. As local stress fields evolve after earthquakes, the CFZ can slip and then trigger instability on the entire DST. It is tempting to relate the 363 pair to the triggering of the 365 CE East Mediterranean earthquake burst.

Living and dead foraminiferal assemblages from an active submarine canyon and surrounding sectors: the Gioia Canyon system (Tyrrhenian Sea, Southern Italy)

NASA Astrophysics Data System (ADS)

Letizia, Di Bella; Martina, Pierdomenico; Roberta, Porretta; Chiocci, Francesco Latino; Eleonora, Martorelli

2017-05-01

Living (rose Bengal stained) and dead benthic foraminiferal assemblages were studied from 23 stations located between 60 and 670 m depth along the Gioia Canyon and the adjacent continental shelf and slope (Southern Tyrrhenian Sea). The aim of this study is to investigate the relationships among sedimentary processes, hydrological patterns and benthic foraminiferal distribution, in a highly dynamic environment. High sedimentation rates on the shelf and occasional turbidity flows along the canyon, lead to unstable environmental conditions at the seafloor that reflect on the microbenthic community influencing faunal density, diversity, species composition and distribution inside the sediment. The foraminiferal distribution seems to be controlled by sedimentary processes, nutrient supply and organic matter recycling, which in turn are strongly controlled by the seasonal variability of riverine inputs and current dynamics in the Gulf of Gioia. From the inner shelf to the upper continental slope (550 m depth), the living foraminiferal assemblage is dominated by agglutinated taxa, likely favored by the high terrigenous supply. Frequent eutrophic taxa (Valvulineria bradyana and Nonionella turgida) tolerant high turbidity (Leptohalysis scottii,) and low oxygen (Bolivina spp. and Bulimina spp.) are recorded on the edge of the inner shelf, where channeling, deposition of coastal deposits and occasional sediment gravity flows occur. In the outer sector of the shelf a turnover of species is observed; L. scottii replaced by the opportunistic species Reophax scorpiurus, and taxa indicative of high energy conditions (Cassidulina spp.) become dominant in association with mesotrophic species like Globocassidulina subglobosa. Along the continental slope, lower sedimentation rates and more stable environmental conditions support richer and more diversified foraminiferal assemblage. The abundance of Bulimina marginata indicates eutrophic conditions at the shallower station (300 m depth) whereas at greater depth (550 m) typical open slope species dominate (Gyroidina spp., Uvigerina mediterranea). Within the Gioia Canyon, benthic assemblage indicates environmental conditions similar to those observed in other Mediterranean and extra-Mediterranean canyons. The assemblage is characterized by eutrophic and low oxygen taxa (Bolivina spp., Bulimina spp.) in relation to periodical fluxes of sediment and organic matter. Similar relationships arise from the analysis of dead foraminiferal assemblages. However, the comparison between living and dead faunas highlight compositional and structural changes related to taphonomic processes.

Regional hard coral distribution within geomorphic and reef flat ecological zones determined by satellite imagery of the Xisha Islands, South China Sea

NASA Astrophysics Data System (ADS)

Zuo, Xiuling; Su, Fenzhen; Zhao, Huanting; Zhang, Junjue; Wang, Qi; Wu, Di

2017-05-01

Coral reefs in the Xisha Islands (also known as the Paracel Islands in English), South China Sea, have experienced dramatic declines in coral cover. However, the current regional scale hard coral distribution of geomorphic and ecological zones, essential for reefs management in the context of global warming and ocean acidification, is not well documented. We analyzed data from field surveys, Landsat-8 and GF-1 images to map the distribution of hard coral within geomorphic zones and reef flat ecological zones. In situ surveys conducted in June 2014 on nine reefs provided a complete picture of reef status with regard to live coral diversity, evenness of coral cover and reef health (live versus dead cover) for the Xisha Islands. Mean coral cover was 12.5% in 2014 and damaged reefs seemed to show signs of recovery. Coral cover in sheltered habitats such as lagoon patch reefs and biotic dense zones of reef flats was higher, but there were large regional differences and low diversity. In contrast, the more exposed reef slopes had high coral diversity, along with high and more equal distributions of coral cover. Mean hard coral cover of other zones was <10%. The total Xisha reef system was estimated to cover 1 060 km2, and the emergent reefs covered 787 m2. Hard corals of emergent reefs were considered to cover 97 km2. The biotic dense zone of the reef flat was a very common zone on all simple atolls, especially the broader northern reef flats. The total cover of live and dead coral can reach above 70% in this zone, showing an equilibrium between live and dead coral as opposed to coral and algae. This information regarding the spatial distribution of hard coral can support and inform the management of Xisha reef ecosystems.

Biosorption of Cd(II) and Cs(I) from aqueous solution by live and dead cells of Saccharomyces carlsbergensis PTCC 5051.

PubMed

Sayyadi, Shayan; Ahmady-Asbchin, Salman; Kamali, Kasra

2018-02-01

The biosorption characteristics of Cd(II) and Cs(I) using live and dead cells of Saccharomyces carlsbergensis PTCC 5051 as biosorbents have been investigated in the present research. The influence of different experimental parameters such as initial pH (pHi), shaking rate, sorption time and initial metal concentration was evaluated. The optimum pH was obtained as 4 for Cd(II) and 7 for Cs(I). The experimental adsorption data were fitted to the Langmuir linear equation adsorption model. The highest metal uptake values of 0.593 and 0.473 mmol g -1 were calculated for Cd(II) and Cs(I), respectively. The results of Fourier transform infrared analysis suggested the involvement of amine, carboxyl and hydroxyl groups during the biosorption process and also indicated that more functional groups were involved in the biosorption process of live adsorbents, compared with those linked to dead biomass. The results showed that the biomass of S. carlsbergensis PTCC 5051 is a suitable biosorbent for the removal of Cd(II) and Cs(I) from the aqueous solutions.

Fungal Transformation of Tree Stumps into a Suitable Resource for Xylophagous Beetles via Changes in Elemental Ratios

PubMed Central

Filipiak, Michał; Sobczyk, Łukasz; Weiner, January

2016-01-01

The elements present in dead pine stumps inhabited by larvae of wood-boring beetles (Stictoleptura rubra, Arhopalus rusticus and Chalcophora mariana) were analyzed over the initial (first 5 years; a chronosequence) stages of wood decay. The quantities of N, P, K, Ca, Mg, Fe, Zn, Mn, Cu and Na (but not S) increased with increases in the content of ergosterol (used as a proxy for the amount of fungal tissue). In fact, the amounts of P, N, K, Fe and Cu presented marked increases. These findings show that fungi stoichiometrically rearrange dead wood by importing externally occurring nutrients to decaying stumps. During the first years of wood decay, the ratios of C to other elements decrease substantially, but differently, for various elements, whereas the N:Fe, N:Cu, N:P and N:K ratios remain relatively stable. Therefore, the stoichiometric mismatch between xylophages and their food is greatly reduced. By changing the nutritional stoichiometry of dead wood, fungi create a nutritional niche for wood-eaters, and these changes enable the development of xylophages.

Tolerance to high temperature and salinity by tadpoles of the Philippine frog, Rana cancrivora

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

Dunson, W.A.

1977-05-25

Amphibians as a group are considered rather intolerant of temperatures above 38C. Tadpoles were found in Philippine tidal pools which were as hot as 42C near midday. This represents an increase of about 3C over the previously recorded high temperature for tadpole survival. Groups of tadpoles were collected and acclimated at 22 to 25C and 35C for 5 to 21 days. Survival time was measured at 40 to 45C at 20% sea water. Tadpoles acclimated at 35C survived much longer. At 42C survival was greater than 40 h. A further test of tadpole survival in dilutions of seawater was mademore » at 25C. Tadpoles were placed 5 days each at 0, 20, 40, 60, 80 and 100% sea water. The percentage dead at end of 5 day period was 0, 0, 0, 5, 33, and 100%. The survival was more than 50% up through 80% sea water. (MU)« less

Brevetoxin exposure in sea turtles in south Texas (USA) during Karenia brevis red tide.

PubMed

Walker, Jennifer Shelby; Shaver, Donna J; Stacy, Brian A; Flewelling, Leanne J; Broadwater, Margaret H; Wang, Zhihong

2018-01-31

Five green (Chelonia mydas) and 11 Kemp's ridley (Lepidochelys kempii) sea turtles found dead, or that died soon after stranding, on the southern Texas (USA) coast during 2 Karenia brevis blooms (October 2015, September-October 2016) were tested for exposure to brevetoxins (PbTx). Tissues (liver, kidney) and digesta (stomach and intestinal contents) were analyzed by ELISA. Three green turtles found alive during the 2015 event and 2 Kemp's ridley turtles found alive during the 2016 event exhibited signs of PbTx exposure, including lethargy and/or convulsions of the head and neck. PbTx were detected in 1 or more tissues or digesta in all 16 stranded turtles. Detected PbTx concentrations ranged from 2 to >2000 ng g-1. Necropsy examination and results of PbTx analysis indicated that 10 of the Kemp's ridleys and 2 of the green turtles died from brevetoxicosis via ingestion. This is the first documentation of sea turtle mortality in Texas attributed to brevetoxicosis.

STS-57 Earth observation of the Eastern Mediterranean, Nile River, Asia Minor

NASA Technical Reports Server (NTRS)

1993-01-01

STS-57 Earth observation of the Eastern Mediterranean. From a high vantage point over the Nile River, this north-looking view shows the eastern Mediterranean and the entire landmass of Asia Minor, with the Black Sea dimly visible at the horizon. Many of the Greek islands can be seen in the Aegean Sea (top left), off the coast of Asia Minor. Cyprus is visible under atmospheric dust in the northeastern corner of the Mediterranean. The dust cloud covers the east end of the Mediterranean, its western edge demarcated by a line that cuts the center of the Nile Delta. This dust cloud originated far to the west, in Algeria, and moved northeast. A gyre of clouds in the southeast corner of the Mediterranean indicates a complementary counterclockwise (cyclonic) circulation of air. The Euphrates River appears as a thin green line (upper right) in the yellow Syrian desert just south of the mountains of Turkey. The Dead Sea (lower right) lies in a rift valley which extends north into Turkey and sout

Marine debris and human impacts on sea turtles in southern Brazil.

PubMed

Bugoni, L; Krause, L; Petry, M V

2001-12-01

Dead stranded sea turtles were recovered and examined to determine the impact of anthropogenic debris and fishery activities on sea turtles on the coast of Rio Grande do Sul State, Brazil. Esophagus/stomach contents of 38 juvenile green Chelonia mydas, 10 adults and sub-adults loggerhead Caretta caretta, and two leatherback Dermochelys coriacea turtles (adult or sub-adult) included plastic bags as the main debris ingested, predominated by white and colorless pieces. The ingestion of anthropogenic debris accounted for the death of 13.2% of the green turtles examined. Signs of damage over the body and carapace indicated that fishing activities caused the death of 13.6% (3/22) of loggerheads and 1.5% (1/56) of green turtles. Therefore, it appears that direct and indirect effects of fishing activities may pose a threat to these species in Brazilian waters. Other sources of plastic debris should be investigated as well as the direct impact of fisheries, especially bottom trawl and gill nets, in order to establish effective conservation action.

GEMINI-7 - EARTH-SKY VIEW - MIDDLE-EAST AREA - OUTER SPACE

NASA Image and Video Library

1965-12-08

S65-63849 (8 Dec. 1965) --- The eastern Mediterranean area as seen from the National Aeronautics and Space Administration's Gemini-7 spacecraft. The Nile Delta in Egypt is at bottom. The Suez Canal, Gulf of Suez and Red Sea are in the center of the photograph. The Sinai Peninsula is in the upper right corner of the picture. The body of water at the top edge of the photograph is the Gulf of Aqaba. The Dead Sea can be seen at top center. Israel, Palestine, Jordan and Syria are also at top center. The Island of Cyprus is at extreme left. Astronauts Frank Borman and James A. Lovell Jr. took this picture using a modified 70mm Hasselblad camera, with Eastman Kodak, Ektachrome MS (S.O. 217) color film. Photo credit: NASA

First report and characterization of adult Uncinaria spp. in New Zealand Sea Lion (Phocarctos hookeri) pups from the Auckland Islands, New Zealand.

PubMed

Castinel, A; Duignan, P J; Pomroy, W E; Lyons, E T; Nadler, S A; Dailey, M D; Wilkinson, I S; Chilvers, B L

2006-03-01

Two species of hookworms (Uncinaria lucasi and Uncinaria hamiltoni) have been formally described from pinnipeds, but dissimilar types are noted from these hosts. This report is the first description of hookworms (Uncinaria spp.) from the New Zealand sea lion, Phocarctos hookeri. The nematodes were collected from dead pups on Enderby Island (Auckland Islands, 50 degrees 30', 166 degrees 17') during January and February, 2004. Standard measurements of male and female hookworms were obtained, providing a general morphometric characterization of the hookworm species in P. hookeri. Considerable variations in the body length of adult hookworms were noted within the same host. The arrangement of some of the bursal rays differs from that described for U. lucasi and U. hamiltoni.

Sea otter mortality in fish and shellfish traps: Estimating potential impacts and exploring possible solutions

USGS Publications Warehouse

Hatfield, B.B.; Ames, J.A.; Estes, J.A.; Tinker, M.T.; Johnson, A.B.; Staedler, M.M.; Harris, M.D.

2011-01-01

Sea otters Enhydra lutris can be bycaught and drowned in fishing pots and traps, which may pose a threat to the welfare of otter populations. We explored this potential problem and its solutions using a wide variety of analyses. We exposed live California (USA) sea otters to finfish traps, lobster traps, and mock Dungeness crab traps in captive trials and found that the animals attempted to enter the circular and rectangular fyke openings, with some becoming entrapped. Using both live and dead sea otters, we found that a 3 ?? 9 inch (7.6 ?? 22.9 cm) fyke opening (1 inch narrower than the 4 ?? 9 inch [10.2 ?? 22.9 cm] openings currently used in California's commercial Dungeness crab fishery) would exclude most free-living (i.e. weaned from their mothers) otters while permitting the undiminished capture of crabs. Observer programs do not currently exist in California for these fisheries, so we calculated the effort required by an observer program to document sea otter bycatch over a range of hypothetical levels and evaluated the impact of those mortality rates on population growth. These analyses demonstrate that significant mortality from bycatch might easily go undetected, even with seemingly high levels of observer effort. As sea otters reoccupy portions of their former habitat in California, co-occurrence with finfish and shellfish traps with relatively large fyke openings will increase. ?? Inter-Research 2011.

Legacy phosphorus in the Baltic Sea and implications for reversing eutrophication

NASA Astrophysics Data System (ADS)

McCrackin, M. L.; Gustafsson, B.; Humborg, C.; Hong, B.; Svanbäck, A.; Swaney, D. P.; Viktorsson, L.

2015-12-01

Eutrophication has depleted concentrations of dissolved oxygen in bottom waters of the Baltic Sea, resulting in the world's largest "dead" zone. A number of measures have been implemented to reduce nutrient inputs and, indeed, between 1995 and 2012 phosphorus (P) loads to the sea deceased 19%. The long-term accumulation and subsequent release of P from both the catchment and marine sediments combined with 30-year water residence times could significantly delay recovery from eutrophication. We estimated net P accumulation (legacy P) for the Baltic Sea using the Net Anthropogenic Phosphorus Inputs (NAPI) approach and historical records of food and feed trade and riverine fluxes. Net P inputs to the catchment peaked at 0.7 million tons per year during the 1970's and since the political and economical changes in Eastern Europe during the 1990's, decreased to 0.2-0.3 million tons per year. P accumulation on land is ten times greater than accumulation in the sea (20 million and 2 million tons, respectively). Of the P retained on land, the majority (18-19 million tons) is in agricultural lands, with the balance in lake sediments. Of the 2 million tons in the sea, two-thirds are in sediments and one-third in the water column. The success of nutrient management actions in reducing river nutrient fluxes will lead to improvement in the Baltic Sea environment, but the massive accumulation of P on land will complicate efforts to achieve complete recovery.

Diatoms dominate the eukaryotic metatranscriptome during spring in coastal 'dead zone' sediments.

PubMed

Broman, Elias; Sachpazidou, Varvara; Dopson, Mark; Hylander, Samuel

2017-10-11

An important characteristic of marine sediments is the oxygen concentration that affects many central metabolic processes. There has been a widespread increase in hypoxia in coastal systems (referred to as 'dead zones') mainly caused by eutrophication. Hence, it is central to understand the metabolism and ecology of eukaryotic life in sediments during changing oxygen conditions. Therefore, we sampled coastal 'dead zone' Baltic Sea sediment during autumn and spring, and analysed the eukaryotic metatranscriptome from field samples and after incubation in the dark under oxic or anoxic conditions. Bacillariophyta (diatoms) dominated the eukaryotic metatranscriptome in spring and were also abundant during autumn. A large fraction of the diatom RNA reads was associated with the photosystems suggesting a constitutive expression in darkness. Microscope observation showed intact diatom cells and these would, if hatched, represent a significant part of the pelagic phytoplankton biomass. Oxygenation did not significantly change the relative proportion of diatoms nor resulted in any major shifts in metabolic 'signatures'. By contrast, diatoms rapidly responded when exposed to light suggesting that light is limiting diatom development in hypoxic sediments. Hence, it is suggested that diatoms in hypoxic sediments are on 'standby' to exploit the environment if they reach suitable habitats. © 2017 The Author(s).

Insurgency in Ancient Times: The Jewish Revolts Against the Seleucid and Roman Empires, 166 BC-73 AD

DTIC Science & Technology

2005-05-26

apocalyptic doctrine. One particular sect of the Essenes was the Qumran which is fairly well known today because they are believed to be the authors of...the Dead Sea Scrolls. The Qumran is believed to have come into existence in the late Hasmonean period and they are illustrative of one of many...Jewish nation. The Qumran also refers to a Teacher of Righteousness, who is a priest and a prophet. Additionally, this individual is referred to in

Modern Microbial Fossilization Processes as Signatures for Interpreting Ancient Terrestrial and Extraterrestrial Microbial Forms

NASA Technical Reports Server (NTRS)

Morris, Penny A.; Wentworth, Susan J.; Nelman, Mayra; Byrne, Monica; Longazo, Teresa; Galindo, Charles; McKay, David S.; Sams, Clarence

2003-01-01

Terrestrial biotas from microbially dominated hypersaline environments will help us understand microbial fossilization processes. Hypersaline tolerant biota from Storr's Lake, San Salvador Island (Bahamas), Mono Lake (California), and the Dead Sea (Israel) represent marine and nonmarine sites for comparative studies of potential analogs for interpreting some Mars meteorites and Mars sample return rocks [1,2,3,4,5,6]. The purpose of this study is to compare microbial fossilization processes, the dominant associated minerals, and potential diagenic implications.

Study of Pure Proteins, Nucleic Acids and Their Complexes from Halobacteria of the Dead Sea: RNA Polymerase-DNA Interaction.

DTIC Science & Technology

1987-09-21

objectives of our program are to isolate and characterize a fully active DNA dependent RNA polymerase from the extremely halophilic archaebacteria of the genus...operons in II. Marismortui. The halobacteriaceae are extreme halophiles . They require 3.5 M NaCI for optimal growth an(l no growth is observed below 2...was difficutlt to perform due to the extreme genetic instability in this strain (6). In contrast, the genoine of the extreme halophilic and prototrophic

A Chance in Hell: Evaluating the Efficacy of U.S. Military Health Systems in Foreign Disaster Relief

DTIC Science & Technology

2013-12-10

no direct access to rail or sea. Many of these roads were severed in the 2005 quake due to landslides.127 Regional tensions with India and...to the timing of the quake , many of the dead and injured were schoolchildren whose classrooms collapsed around them. 132Sharon Wiharta et al., The...139According to NATO’s Euro-Atlantic Response Center Report dated October 8, the top two priorities were rescue/cargo helicopters and earth moving

Postglacial Fringing-Reef to Barrier-Reef conversion on Tahiti links Darwin's reef types

NASA Astrophysics Data System (ADS)

Blanchon, Paul; Granados-Corea, Marian; Abbey, Elizabeth; Braga, Juan C.; Braithwaite, Colin; Kennedy, David M.; Spencer, Tom; Webster, Jody M.; Woodroffe, Colin D.

2014-05-01

In 1842 Charles Darwin claimed that vertical growth on a subsiding foundation caused fringing reefs to transform into barrier reefs then atolls. Yet historically no transition between reef types has been discovered and they are widely considered to develop independently from antecedent foundations during glacio-eustatic sea-level rise. Here we reconstruct reef development from cores recovered by IODP Expedition 310 to Tahiti, and show that a fringing reef retreated upslope during postglacial sea-level rise and transformed into a barrier reef when it encountered a Pleistocene reef-flat platform. The reef became stranded on the platform edge, creating a lagoon that isolated it from coastal sediment and facilitated a switch to a faster-growing coral assemblage dominated by acroporids. The switch increased the reef's accretion rate, allowing it to keep pace with rising sea level, and transform into a barrier reef. This retreat mechanism not only links Darwin's reef types, but explains the re-occupation of reefs during Pleistocene glacio-eustacy.

Use of recombinant calreticulin and cercarial transformation fluid (CTF) in the serodiagnosis of Schistosoma mansoni.

PubMed

El Aswad, Bahaa El Deen Wade; Doenhoff, Michael J; El Hadidi, Abeer Shawky; Schwaeble, Wilhelm J; Lynch, Nicholas J

2011-03-01

Schistosomiasis is traditionally diagnosed by microscopic detection of ova in stool samples, but this method is labour intensive and its sensitivity is limited by low and variable egg secretion in many patients. An alternative is an ELISA using Schistosoma mansoni soluble egg antigen (SEA) to detect anti-schistosome antibody in patient samples. SEA is a good diagnostic marker in non-endemic regions but is of limited value in endemic regions, mainly because of its high cost and limited specificity. Here we assess seven novel antigens for the detection of S. mansoni antibody in an endemic region (the Northern Nile Delta). Using recombinant S. mansoni calreticulin (CRT) and fragments thereof, anti-CRT antibodies were detected in the majority of 97 patients sera. The diagnostic value of some of these antigens was, however, limited by the presence of cross-reacting antibody in the healthy controls, even those recruited in non-endemic areas. Cercarial transformation fluid (CTF), a supernatant that contains soluble material released by the cercariae upon transformation to the schistosomula, is cheaper and easier to produce than SEA. An ELISA using CTF as the detection antigen had a sensitivity of 89.7% and an estimated specificity of 100% when used in non-endemic regions, matching the performance of the established SEA ELISA. CTF was substantially more specific than SEA for diagnosis in the endemic region, and less susceptible than SEA to cross-reacting antibody in the sera of controls with other protozoan and metazoan infections. Copyright © 2010 Elsevier GmbH. All rights reserved.

Diversity of terrestrial avifauna in response to distance from the shoreline of the Salton Sea

USGS Publications Warehouse

Mendelsohn, M.B.; Boarman, W.I.; Fisher, R.N.; Hathaway, S.A.

2007-01-01

Large aquatic bodies influence surrounding terrestrial ecosystems by providing water and nutrients. In arid landscapes, the increased primary productivity that results may greatly enhance vertebrate biodiversity. The Salton Sea, a large saline lake in the Colorado Desert of southern California, provides nutrients in the form of hundreds of thousands of dead fish carcasses, brine flies, and chemical compounds through windborne salt sea spray. We performed point counts for landbirds and shorebirds monthly or every other month between March 2001 and February 2002 across a sampling grid of 35 points along the west edge of Salton Sea. We found that avian diversity (numbers of species and numbers per species) was dependent on proximity to the Sea. Diversity was at a maximum nearest the shore, and was significantly lower away from the Sea's edge, at all surveyed distances up to 1 km from the shore. Cover by the dominant shrubs on the study site also corresponded to proximity to the water's edge. Whereas one may hypothesize that the avian diversity patterns are caused by these differences in vegetation structure, our data did not support this. Future studies should further investigate this potential correlation between vegetation and bird patterns. Until more is understood about the relationship between elevated avian diversity and the physical environment of the land-shore interface, our results suggest that the Sea's surface be stabilized near its present level. Future management schemes at the Salton Sea that include reductions of water sources should be carefully analyzed, so as to not jeopardize the terrestrial avifauna at this unique ecosystem. ?? 2006 Elsevier Ltd. All rights reserved.

Experimental recovery of sea otter carcasses at Kodiak Island, Alaska, following the Exxon Valdez oil spill

USGS Publications Warehouse

DeGange, Anthony R.; Doroff, Angela M.; Monson, Daniel H.

1994-01-01

ound,  Alaska,  spilling  approximately  11  million  barrels  of  crude  oil.  Oil  wasdeposited  on  beaches  nearly  700  km  from  the  spill  site  (Galt  and  Payton  1990,Piatt  et  al.  1990),  affecting  thousands  of  hectares  of  sea  otter(Enhydra  lutris)habitat.  Two  of  the  principal  limitations  in  determining  the  initial  effects  of  theExxon  Valdez  oil  spill  on  sea  otter  populations  were  a  lack  of  recent  populationdata,  and  a  lack  of  information  on  the  proportion  of  the  total  number  of  seaotters  killed  by  the  spill  that  were  actually  recovered.ound,  Alaska,  spilling  approximately  11  million  barrels  of  crude  oil.  Oil  wasdeposited  on  beaches  nearly  700  km  from  the  spill  site  (Galt  and  Payton  1990,Piatt  et  al.  1990),  affecting  thousands  of  hectares  of  sea  otter(Enhydra  lutris)habitat.  Two  of  the  principal  limitations  in  determining  the  initial  effects  of  theExxon  Valdez  oil  spill  on  sea  otter  populations  were  a  lack  of  recent  populationdata,  and  a  lack  of  information  on  the  proportion  of  the  total  number  of  seaotters  killed  by  the  spill  that  were  actually  recovered.On 24 March 1989, the T/V Exxon Valdez ran aground in Prince William Sound, Alaska, spilling approximately 11 million barrels of crude oil. Oil was deposited on beaches nearly 700 km from the spill site (Galt and Payton 1990, Piatt et al. 1990), affecting thousands of hectares of sea otter (Enhydra lutris) habitat. Two of the principal limitations in determining the initial effects of the Exxon Valdez oil spill on sea otter populations were a lack of recent population data, and a lack of information on the proportion of the total number of sea otters killed by the spill that were actually recovered.In late April and early May oil spread to the Kodiak Archipelago. With the oil came wildlife rescue, beach cleanup, and other spill-response activities including searches for dead birds and mammals. We took this opportunity to assess experimentally the recovery of sea otter carcasses in the Kodiak Island area. Specifically, we were interested in the proportion of the total number of dead sea otters the recovered carcasses represented.

A Conserved Metal Binding Motif in the Bacillus subtilis Competence Protein ComFA Enhances Transformation.

PubMed

Chilton, Scott S; Falbel, Tanya G; Hromada, Susan; Burton, Briana M

2017-08-01

Genetic competence is a process in which cells are able to take up DNA from their environment, resulting in horizontal gene transfer, a major mechanism for generating diversity in bacteria. Many bacteria carry homologs of the central DNA uptake machinery that has been well characterized in Bacillus subtilis It has been postulated that the B. subtilis competence helicase ComFA belongs to the DEAD box family of helicases/translocases. Here, we made a series of mutants to analyze conserved amino acid motifs in several regions of B. subtilis ComFA. First, we confirmed that ComFA activity requires amino acid residues conserved among the DEAD box helicases, and second, we show that a zinc finger-like motif consisting of four cysteines is required for efficient transformation. Each cysteine in the motif is important, and mutation of at least two of the cysteines dramatically reduces transformation efficiency. Further, combining multiple cysteine mutations with the helicase mutations shows an additive phenotype. Our results suggest that the helicase and metal binding functions are two distinct activities important for ComFA function during transformation. IMPORTANCE ComFA is a highly conserved protein that has a role in DNA uptake during natural competence, a mechanism for horizontal gene transfer observed in many bacteria. Investigation of the details of the DNA uptake mechanism is important for understanding the ways in which bacteria gain new traits from their environment, such as drug resistance. To dissect the role of ComFA in the DNA uptake machinery, we introduced point mutations into several motifs in the protein sequence. We demonstrate that several amino acid motifs conserved among ComFA proteins are important for efficient transformation. This report is the first to demonstrate the functional requirement of an amino-terminal cysteine motif in ComFA. Copyright © 2017 American Society for Microbiology.

Bones as biofuel: a review of whale bone composition with implications for deep-sea biology and palaeoanthropology

PubMed Central

Higgs, Nicholas D.; Little, Crispin T. S.; Glover, Adrian G.

2011-01-01

Whales are unique among vertebrates because of the enormous oil reserves held in their soft tissue and bone. These ‘biofuel’ stores have been used by humans from prehistoric times to more recent industrial-scale whaling. Deep-sea biologists have now discovered that the oily bones of dead whales on the seabed are also used by specialist and generalist scavenging communities, including many unique organisms recently described as new to science. In the context of both cetacean and deep-sea invertebrate biology, we review scientific knowledge on the oil content of bone from several of the great whale species: Balaenoptera musculus, Balaenoptera physalus, Balaenoptera borealis, Megaptera novaeangliae, Eschrichtius robustus, Physeter macrocephalus and the striped dolphin, Stenella coeruleoalba. We show that data collected by scientists over 50 years ago during the heyday of industrial whaling explain several interesting phenomena with regard to the decay of whale remains. Variations in the lipid content of bones from different parts of a whale correspond closely with recently observed differences in the taphonomy of deep-sea whale carcasses and observed biases in the frequency of whale bones at archaeological sites. PMID:20702457

Discriminating Sea Spikes in Incoherent Radar Measurements of Sea Clutter

DTIC Science & Technology

2008-03-01

het detecteren echter niet te verwachten dat bet gebruik van sea spikes te onderzoeken. Een van deze modellen zal leiden tot een Auteur (s) dergelijk...report I TNO-DV 2008 A067 6/33 Abbreviations CFAR Constant False-Alarm Rate CST Composite Surface Theory FFT Fast Fourier Transform PDF Probability Density...described by the composite surface theory (CST). This theory describes the sea surface as small Bragg-resonant capillary waves riding on top of

High Grazing Angle and High Resolution Sea Clutter: Correlation and Polarisation Analyses

DTIC Science & Technology

2007-03-01

the azimuthal correlation. The correlation between the HH and VV sea clutter data is low. A CA-CFAR ( cell average constant false-alarm rate...to calculate the power spectra of correlation profiles. The frequency interval of the traditional Discrete Fourier Transform is NT1 Hz, where N and...sea spikes, the Entropy-Alpha decomposition of sea spikes is shown in Figure 30. The process first locates spikes using a cell -average constant false

Wildfires in Chernobyl-contaiminated forests and risks to the population and the environment: A new nuclear disaster about to happen?

Treesearch

Nikolaos Evangeliou; Yves Balkanski; Anne Cozic; Wei Min Hao; Anders Pape Moller

2014-01-01

Radioactive contamination in Ukraine, Belarus and Russia after the Chernobyl accident left large rural and forest areas to their own fate. Forest succession in conjunction with lack of forest management started gradually transforming the landscape. During the last 28 years dead wood and litter have dramatically accumulated in these areas, whereas climate change has...

I Want the People to Observe and to Learn! The St Petersburg "Kunstkamera" in the Eighteenth Century

ERIC Educational Resources Information Center

Baird, Olga A.

2008-01-01

The radical reforms of Peter the Great of Russia (1672-1725) transformed the whole country. Among his educational reforms, the establishment in 1714 of the first public museum as a tool for public education had no precedents in Russian history. Its functions were formulated as "teaching and enlarging knowledge of nature, dead and alive, and…

Ionoregulatory changes during metamorphosis and salinity exposure of juvenile sea lamprey (Petromyzon marinus L.)

USGS Publications Warehouse

Reis-Santos, P.; McCormick, S.D.; Wilson, J.M.

2008-01-01

Ammocoetes of the anadromous sea lamprey Petromyzon marinus L. spend many years in freshwater before metamorphosing and migrating to sea. Metamorphosis involves the radical transformation from a substrate-dwelling, filter feeder into a free-swimming, parasitic feeder. In the present work we examined osmoregulatory differences between ammocoetes and transformers (metamorphic juveniles), and the effects of salinity acclimation. We measured the expression of key ion-transporting proteins [Na+/K+-ATPase, vacuolar (V)-type H+-ATPase and carbonic anhydrase (CA)] as well as a number of relevant blood parameters (hematocrit, [Na+] and [Cl -]). In addition, immunofluorescence microscopy was used to identify and characterize the distributions of Na+/K+-ATPase, V-type H+-ATPase and CA immunoreactive cells in the gill. Ammocoetes did not survive in the experiments with salinities greater than 10???, whereas survival in high salinity (???25-35???) increased with increased degree of metamorphosis in transformers. Plasma [Na+] and [Cl -] of ammocoetes in freshwater was lower than transformers and increased markedly at 10???. In transformers, plasma ions increased only at high salinity (>25???). Branchial Na+/K+-ATPase levels were ??? tenfold higher in transformers compared to ammocoetes and salinity did not affect expression in either group. However, branchial H +-ATPase expression showed a negative correlation with salinity in both groups. Na+/K+-ATPase immunoreactivity was strongest in transformers and associated with clusters of cells in the interlamellar spaces. H+-ATPase (B subunit) immunoreactivity was localized to epithelial cells not expressing high Na+/K+-ATPase immunoreactivity and having a similar tissue distribution as carbonic anhydrase. The results indicate that branchial Na+/K+-ATPase and salinity tolerance increase in metamorphosing lampreys, and that branchial H+-ATPase is downregulated by salinity.

Photo-damage protective effect of two facial products, containing a unique complex of Dead Sea minerals and Himalayan actives.

PubMed

Wineman, Eitan; Portugal-Cohen, Meital; Soroka, Yoram; Cohen, Dror; Schlippe, Gerrit; Voss, Werner; Brenner, Sarah; Milner, Yoram; Hai, Noam; Ma'or, Zeevi

2012-09-01

Skin appearance is badly affected when exposed to solar UV rays, which encourage physiological and structural cutaneous alterations that eventually lead to skin photo-damage. To test the capability of two facial preparations, extreme day cream (EXD) and extreme night treatment (EXN), containing a unique complex of Dead Sea water and three Himalayan extracts, to antagonize biological effects induced by photo-damage. Pieces of organ cultures of human skin were used as a model to assess the biological effects of UVB irradiation and the protective effect of topical application of two Extreme preparations. Skin pieces were analyzed for mitochondrial activity by MTT assay, for apoptosis by caspase 3 assay, and for cytokine secretion by solid phase ELISA. Human subjects were tested to evaluate the effect of Extreme preparations on skin wrinkle depth using PRIMOS and skin hydration by a corneometer. UVB irradiation induced cell apoptosis in the epidermis of skin organ cultures and increased their pro-inflammatory cytokine, tumor necrosis α (TNFα) secretion. Topical applications of both preparations significantly attenuated all these effects. Furthermore, in human subjects, a reduction in wrinkle depth and an elevation in the intense skin moisture were observed. The observations clearly show that EXD and EXN preparations have protective anti-apoptotic and anti-inflammatory properties that can attenuate biological effects of skin photo-damage. Topical application of the preparations improves skin appearance by reducing its wrinkles depth and increasing its moisturizing impact. © 2012 Wiley Periodicals, Inc.

Dead Sea mud packs for chronic low back pain.

PubMed

Abu-Shakra, Mahmoud; Mayer, Amit; Friger, Michael; Harari, Marco

2014-09-01

Low back pain (LBP) is chronic disease without a curative therapy. Alternative and complementary therapies are widely used in the management of this condition. To evaluate the efficacy of home application of Dead Sea mud compresses to the back of patients with chronic LBP. Forty-six consecutive patients suffering from chronic LBP were recruited. All patients were followed at the Soroka University Rheumatic Diseases Unit. The patients were randomized into two groups: one group was treated with mineral-rich mud compresses, and the other with mineral-depleted compresses. Mud compresses were applied five times a week for 3 consecutive weeks. The primary outcome was the patient's assessment of the overall back pain severity. The score of the Ronald & Morris questionnaire served as a secondary outcome. Forty-four patients completed the therapy and the follow-up assessments: 32 were treated with real mud packs and 12 used the mineral-depleted packs. A significant decrease in intensity of pain, as described by the patients, was observed only in the treatment group. In this group, clinical improvement was clearly seen at completion of therapy and was sustained a month later. Significant improvement in the scores of the Roland & Morris questionnaire was observed in both groups. The data suggest that pain severity was reduced in patients treated with mineral-rich mud compresses compared with those treated with mineral-depleted compresses. Whether this modest effect is the result of a "true" mud effect or other causes can not be determined in this study.

Quantitative assessment of glacial fluctuations in the level of Lake Lisan, Dead Sea rift

NASA Astrophysics Data System (ADS)

Rohling, Eelco J.

2013-06-01

A quantitative understanding of climatic variations in the Levant during the last glacial cycle is needed to support archaeologists in assessing the drivers behind hominin migrations and cultural developments in this key region at the intersection between Africa and Europe. It will also foster a better understanding of the region's natural variability as context to projections of modern climate change. Detailed documentation of variations in the level of Lake Lisan - the lake that occupied the Dead Sea rift during the last glacial cycle - provides crucial climatic information for this region. Existing reconstructions suggest that Lake Lisan highstands during cold intervals of the last glacial cycle represent relatively humid conditions in the region, but these interpretations have remained predominantly qualitative. Here, I evaluate realistic ranges of the key climatological parameters that controlled lake level, based on the observed timing and amplitudes of lake-level variability. I infer that a mean precipitation rate over the wider catchment area of about 500 mm y-1, as proposed in the literature, would be consistent with observed lake levels if there was a concomitant 15-50% increase in wind speed during cold glacial stadials. This lends quantitative support to previous inferences of a notable increase in the intensity of Mediterranean (winter) storms during glacial periods, which tracked eastward into the Levant. In contrast to highstands during ‘regular’ stadials, lake level dropped during Heinrich Events. I demonstrate that this likely indicates a further intensification of the winds during those times.

Satellite observations of turbidity in the Dead Sea

NASA Astrophysics Data System (ADS)

Nehorai, R.; Lensky, I. M.; Hochman, L.; Gertman, I.; Brenner, S.; Muskin, A.; Lensky, N. G.

2013-06-01

A methodology to attain daily variability of turbidity in the Dead Sea by means of remote sensing was developed. 250 m/pixel moderate resolution imaging spectroradiometer (MODIS) surface reflectance data were used to characterize the seasonal cycle of turbidity and plume spreading generated by flood events in the lake. Fifteen minutes interval images from meteosat second generation 1.6 km/pixel high-resolution visible (HRV) channel were used to monitor daily variations of turbidity. The HRV reflectance was normalized throughout the day to correct for the changing geometry and then calibrated against available MODIS surface reflectance. Finally, hourly averaged reflectance maps are presented for summer and winter. The results show that turbidity is concentrated along the silty shores of the lake and the southern embayments, with a gradual decrease of turbidity values from the shoreline toward the center of the lake. This pattern is most pronounced following the nighttime hours of intense winds. A few hours after winds calm the concentric turbidity pattern fades. In situ and remote sensing observations show a clear relation between wind intensity, wave amplitude and water turbidity. In summer and winter similar concentric turbidity patterns are observed but with a much narrower structure in winter. A simple Lagrangain trajectory model suggests that the combined effects of horizontal transport and vertical mixing of suspended particles leads to more effective mixing in winter. The dynamics of suspended matter contributions from winter desert floods are also presented in terms of hourly turbidity maps showing the spreading of the plumes and their decay.

Gas hydrate and spatial venting variations in the continental margin offshore Southwestern Taiwan

NASA Astrophysics Data System (ADS)

Lin, S.; Lim, Y.; Hsieh, W.; Yang, T.; Wang, Y.

2006-12-01

Strong BSR, high methane contents and rapid sulfate reduction were found in the continental margin sediments offshore southwestern Taiwan. In order to identify the venting phenomena and its relationship with gas hydrate, this research investigate sea floor vent features using WHOI?|s Towcam system as well as piston core in the study region. A total of 10 dives were conducted on board the r/v OR-1. Pore water sulfate, dissolved sulfide, methane, chloride, del O18 ratio, sediment organic carbon, carbonate content and carbonate del C13 ratio, pyrite-S were measured Large spatial variations were found based on pictures obtained from Towcam system and piston cores. Active venting features include bacteria mat, live dense bivalve patches, gas plume, temperature and salinity fluctuations, rapid sulfate reduction and high concentrations of methane in sediments. In addition, vent chimney, pockmark and large authigenic carbonate buildup were also observed in the active venting area. In contrast, in some areas without active venting features, scatter dead chimney, semi- buried carbonate structures, and dead bivalves were found. Total sulfate depletion was found at depth as shallow as 1 meter below sediment water interface in area near active vent whereas almost no sulfate depletion was observed in areas without any vent feature. Stages of carbonate build up existed, with initial phase dominated by small tube, chimney, and later with massive carbonate structures protruding the sea floor. The appearances of massive carbonate buildup structures seemed to indicate the end stage of gas hydrate venting phenomena.

Natural versus human control on subsurface salt dissolution and development of thousands of sinkholes along the Dead Sea coast

NASA Astrophysics Data System (ADS)

Abelson, Meir; Yechieli, Yoseph; Baer, Gidon; Lapid, Gil; Behar, Nicole; Calvo, Ran; Rosensaft, Marcelo

2017-06-01

One of the most hazardous results of the human-induced Dead Sea (DS) shrinkage is the formation of more than 6000 sinkholes over the last 25 years. The DS shrinkage caused eastward retreat of underground brine replaced by fresh groundwater, which in turn dissolved a subsurface salt layer, to generate cavities and collapse sinkholes. The areal growth rate of sinkhole clusters is considered the most pertinent proxy for sinkholes development. Analysis of light detection and ranging, digital elevation models, and interferometric synthetic aperture radar allows translation of the areal growth rate to a salt dissolution rate of the salt layer, revealing two peaks in the history of the salt dissolution rate. These peaks cannot be attributed to the decline of the DS level. Instead, we show that they are related to long-term variations of precipitation in the groundwater source region, the Judea Mountains, and the delayed response of the aquifer system between the mountains and the DS rift. This response is documented by groundwater levels and salinity variations. We thus conclude that while the DS level decline is the major trigger for sinkholes formation, the rainfall variations more than 30 km to the west dominate their evolution rate. The influence of increasing rainfall in the Judea Mountains reaches the DS at a typical time lag of 4 years, and the resulting increase in the salt dissolution rate lags by a total time of 5-6 years.

Salt diapirs in the Dead Sea basin and their relationship to Quaternary extensional tectonics

USGS Publications Warehouse

Al-Zoubi, A.; ten Brink, Uri S.

2001-01-01

Regional extension of a brittle overburden and underlying salt causes differential loading that is thought to initiate the rise of reactive diapirs below and through regions of thin overburden. We present a modern example of a large salt diapir in the Dead Sea pull-apart basin, the Lisan diapir, which we believe was formed during the Quaternary due to basin transtension and subsidence. Using newly released seismic data that are correlated to several deep wells, we determine the size of the diapir to be 13 x 10 km. its maximum depth 7.2 km. and its roof 125 m below the surface. From seismic stratigraphy, we infer that the diapir started rising during the early to middle Pleistocene as this section of the basin underwater rapid subsidence and significant extension of the overburden. During the middle to late Pleistocene, the diapir pierced through the extensionally thinned overburden, as indicated by rim synclines, which attest to rapid salt withdrawal from the surrounding regions. Slight positive topography above the diapir and shallow folded horizons indicate that it is still rising intermittently. The smaller Sedom diapir, exposed along the western bounding fault of the basin is presently rising and forms a 200 m-high ridge. Its initiation is explained by localized E-W extension due monoclinal draping over the edge of a rapidly subsiding basin during the early to middle Pleistocene, and its continued rise by lateral squeezing due to continued rotation of the Amazyahu diagonal fault. 

An adenovirus associated with intestinal impaction and mortality of male eiders (Somateria mollissima) in the Baltic Sea

USGS Publications Warehouse

Hollmén, Tuula E.; Franson, J. Christian; Kilpi, Mikael; Docherty, Douglas E.; Myllys, V.

2003-01-01

We examined 10 common eider (Somateria mollissima) males found dead in 1998 during a die-off in the northern Baltic Sea off the southwestern coast of Finland. We diagnosed impaction of the posterior small intestine with mucosal necrosis as the cause of death in all 10 and isolated adenoviruses from cloacal samples of six birds. The adenovirus isolates were not neutralized by reference antisera to group I, II, or III avian adenoviruses. Cloacal swabs from 22 apparently healthy eider females nesting at the mortality area were negative for viruses. An adenovirus isolated from one of the eiders caused clinical signs of illness and gastrointestinal pathology in experimentally infected mallard (Anas platyrhynchos) ducklings. These findings suggest that the adenovirus contributed to the mortality of common eider males in the Finnish archipelago.

New Challenges, New Mindsets, New Disciplines: Transforming the SEA into a Modern Performance Organization. Solutions. Issue No. 1

ERIC Educational Resources Information Center

Gross, Betheny; Jochim, Ashley; Nafziger, Dean

2013-01-01

State education agencies (SEAs) are under fire and face new expectations from all sides. The federal government, state legislatures and governors, and citizens themselves are calling upon the SEA to do "more"--more to improve outcomes for students, more to close the achievement gap, and more to meet the diverse instructional needs of students.…

Comparison of live and dead molluscan assemblages suggests recent human-driven decline in benthic diversity in Phetchaburi (NW Gulf of Thailand)

NASA Astrophysics Data System (ADS)

Negri, Mauro Pietro; Sanfilippo, Rossana; Basso, Daniela; Rosso, Antonietta

2015-12-01

Dead and live molluscan assemblages from the coastal area of Phetchaburi (NW Gulf of Thailand) were compared by means of multivariate analysis. Seven thanatofacies were recognized, thriving in the area after the 1960s. Five of them, scattered along the tidal flat, represent oligotypic intertidal biotopes linked to a variety of environmental factors; the remaining two mirror high-diversity infralittoral associations. Conversely, only two poor, ill-defined biofacies thrive at present between the intertidal and the shallow infralittoral zones, somewhat resembling two of the thanatofacies. Diversity indexes reveal a dramatic biodiversity decline occurred from the 1960s onwards, far beyond the effects of time-averaging and accumulation. The responsibility for this reduction is largely attributable to the high impact of human activities, such as the intensive sea bottom trawling, the wastewaters from aquaculture (shrimp and fish ponds) and dense coastal villages, and, at a minor extent, the digging of edible molluscs from the tidal flat.

Chemical Composition by the APXS along the Downhill Traverse of the Mars Exploration Rover Spirit at Gusev Crater

NASA Technical Reports Server (NTRS)

Bruckner, J.; Dreibus, G.; Gellert, R.; Clark, B.C.; Cohen, B.; McCoy, T.; Ming, D.W.; Mittlefehldt, D.W.; Yen, A.; Athena Science Team

2006-01-01

The Alpha Particle X-ray Spectrometer (APXS) onboard the Mars Exploration Rover Spirit continues to determine the elemental composition of samples at Gusev Crater. Starting around sol 600 the rover descended Husband Hill, which is part of the Columbia Hills, visited the inner basin with a large dune field, called 'El Dorado', and parked at Low Ridge to conserve energy during the martian winter. Many unique samples were discovered by the instruments onboard Spirit during her downhill traverse. Here, we report only on the chemical data obtained by the APXS. The compositions of some of the soil samples are comparable to the mean soil determined along the earlier traverse. However, a light-toned subsurface sample (disturbed by the rover wheels), called Dead Sea Samra , showed the highest sulfur content of all soil samples, the lowest Na, Mg, Al, Cl, K, Ca, Ti, Mn, and Zn, among the lowest Si and P, and among the highest Cr, Fe and Ni. Assuming ferric sulfate as a major mineral, large amounts of a pure silica phase must be present. Color and quantity of Dead Sea Samra resemble somewhat an earlier soil called Paso Robles , though the latter is a mixture of sulfates with phosphate-rich soil. Manganese in Dead Sea Samra is so low that the Fe/Mn ratio exceeds 300, a value that has never been found previously on Mars (Fe/Mn ratio of 46 for Gusev basalts), indicating that only Fe(3+) occurs. The dune field El Dorado contained granulated material that exhibited the highest Mg and Ni concentrations and the lowest S and Cl compared to all other soils implying an enrichment of olivine-rich sands. Two outcrops, called Algonquin and Comanche , revealed compositions that differ significantly from those of earlier outcrops as they have the highest concentrations of Mg, Fe, and Ni (except for Ni in Independence) and the lowest of Al, K (detection limit), Ca, and Ti of all brushed and almost all abraded rocks. Normative estimates assign them the highest olivine contents ever found for martian rocks and a very mafic nature based on their high Mg/(Mg+Fe) and low Al, Ca and Na. Their significantly high Ni contents point to a different source than the Gusev plains basalts. The elemental compositions of samples encountered during the downhill traverse revealed a larger chemical diversity of the Columbia Hills than the uphill trek already published.

Beryllium isotopes as tracers of Lake Lisan (last Glacial Dead Sea) hydrology and the Laschamp geomagnetic excursion

NASA Astrophysics Data System (ADS)

Belmaker, Reuven; Stein, Mordechai; Beer, Jürg; Christl, Marcus; Fink, David; Lazar, Boaz

2014-08-01

The content of the cosmogenic isotope 10Be (t1/2=1.39 Ma) in lacustrine sediments that deposit in lakes with a large watershed is susceptible to both climate and cosmogenic production rate variations. In order to distinguish between these two controls, we measured 10Be and major elements in several sections of the annually laminated sediments of the Lake Lisan (the last Glacial precursor of the Dead Sea) that are composed of detrital sediments and primary (evaporitic) aragonites. The sections were selected to represent regional hydrology and climate as reflected by different lake configurations (level rise, drop and high-stands) and rapid change in the 10Be production rate during the Laschamp geomagnetic excursion. Since the short-lived cosmogenic “sister” of 10Be, 7Be (t1/2=53.3 d) has virtually no recycled component, the recycled 10Be in Lake Lisan detrital sediments was evaluated by measuring 7Be in their modern equivalents: modern flood suspended matter, dust and mud cracks. Our results demonstrate that although the recycled 10Be component is significant, secular variations in the 10Be concentration in Lake Lisan sediments correlate with hydrological variations and geomagnetic excursions. During periods of moderate variations in 10Be production rate, the 10Be concentration in the Lisan detrital sediments positively correlates with lake level, Al + Fe content and the (Al + Fe)/(Ca + Mg) ratio. These correlations suggest that the 10Be is adsorbed on the fine silicate component (probably clays) of the detrital laminae. The fine silicates together with carbonates were transported to Dead Sea drainage basin mainly as airborne dust that after a short residence time was washed into Lake Lisan as flood suspended matter. We suggest that preferential dissolution of carbonates in the flood suspended matter concentrated the residual fine component leading to the positive correlation between 10Be and the (Al + Fe)/(Ca + Mg) ratio. During periods of increased water discharge more carbonates were dissolved and hence the 10Be concentration in the detrital laminae increased. During periods of rapid increase in the 10Be production rate (e.g. the Laschamp excursion), 10Be showed a ∼2 fold increase, beyond the above-mentioned correlations (lake levels and Al + Fe contents). This observation suggests that Lake Lisan can serve as a potential high-resolution archive of 10Be production rate variations during periods of geomagnetic excursions.

Severe scuticociliate (Philasterides dicentrarchi) infection in a population of sea dragons (Phycodurus eques and Phyllopteryx taeniolatus).

PubMed

Rossteuscher, S; Wenker, C; Jermann, T; Wahli, T; Oldenberg, E; Schmidt-Posthaus, H

2008-07-01

Scuticociliatosis is a disease of fish induced by ciliated parasites of the genus Scuticociliatida. It has been described in sea horses (Hippocampus sp.), flounders (Paralichthys olivaceus), and turbots (Scophthalmus maximus). Here we present a case study of a population of sea dragons chronically infected with scuticociliates identified as Philasterides dicentrarchi by histopathology and PCR. Beginning in 2004, over a period of 19 months, 10 sea dragons (Phycodurus eques and Phyllopteryx taeniolatus) were found dead in an aquarium of the Zoological Garden Basle, Switzerland. Clinically, the animals showed only faint symptoms of disease over a short period of time. At necropsy, macroscopic lesions were confined to the skin with multiple, often hemorrhagic, ulcerations. Histologically, epidermal ulcers were associated with necrosis and inflammation of the underlying dermis and musculature. Numerous ciliates, with a morphology consistent with scuticociliates, were present in these lesions. In several animals these ciliates had invaded blood vessels and were detected in gills and internal organs including kidney, thyroid gland, and central nervous system (CNS). In these organs, mild degenerative lesions and inflammatory reactions were evident. The ciliates were identified as Philasterides dicentrarchi based on small-subunit ribosomal RNA (SSUrRNA) gene sequences obtained by polymerase chain reaction (PCR) on DNA extracted from paraffin-embedded tissue sections. Our report shows that scuticociliate infections of sea dragons can develop into a systemic infection and that both species of sea dragons can be affected.

Transient groundwater-lake interactions in a continental rift: Sea of Galilee, Israel

USGS Publications Warehouse

Hurwitz, S.; Stanislavsky, E.; Lyakhovsky, V.; Gvirtzman, H.

2000-01-01

The Sea of Galilee, located in the northern part of the Dead Sea rift, is currently an intermediate fresh-water lake. It is postulated that during a short highstand phase of former Lake Lisan in the late Pleistocene, saline water percolated into the subsurface. Since its recession from the Kinarot basin and the instantaneous formation of the fresh-water lake (the Sea of Galilee), the previously intruded brine has been flushed backward toward the lake. Numerical simulations solving the coupled equations of fluid flow and of solute and heat transport are applied to examine the feasibility of this hypothesis. A sensitivity analysis shows that the major parameters controlling basin hydrodynamics are lake-water salinity, aquifer permeability, and aquifer anisotropy. Results show that a highstand period of 3000 yr in Lake Lisan was sufficient for saline water to percolate deep into the subsurface. Because of different aquifer permeabilities on both sides of the rift, brine percolated into a aquifers on the western margin, whereas percolation was negligible on the eastern side. In the simulation, after the occupation of the basin by the Sea of Galilee, the invading saline water was leached backward by a topography-driven flow. It is suggested that the percolating brine on the western side reacted with limestone at depth to form epigenetic dolomite at elevated temperatures. Therefore, groundwater discharging along the western shores of the Sea of Galilee has a higher calcium to magnesium ratio than groundwater on the eastern side.

Recovery of transplantable organs after cardiac or circulatory death: Transforming the paradigm for the ethics of organ donation

PubMed Central

Verheijde, Joseph L; Rady, Mohamed Y; McGregor, Joan

2007-01-01

Organ donation after cardiac or circulatory death (DCD) has been introduced to increase the supply of transplantable organs. In this paper, we argue that the recovery of viable organs useful for transplantation in DCD is not compatible with the dead donor rule and we explain the consequential ethical and legal ramifications. We also outline serious deficiencies in the current consent process for DCD with respect to disclosure of necessary elements for voluntary informed decision making and respect for the donor's autonomy. We compare two alternative proposals for increasing organ donation consent in society: presumed consent and mandated choice. We conclude that proceeding with the recovery of transplantable organs from decedents requires a paradigm change in the ethics of organ donation. The paradigm change to ensure the legitimacy of DCD practice must include: (1) societal agreement on abandonment of the dead donor rule, (2) legislative revisions reflecting abandonment of the dead donor rule, and (3) requirement of mandated choice to facilitate individual participation in organ donation and to ensure that decisions to participate are made in compliance with the societal values of respect for autonomy and self-determination. PMID:17519030

Tectonic and hydrological controls on multiscale deformations in the Levant: numerical modeling and theoretical analysis

NASA Astrophysics Data System (ADS)

Belferman, Mariana; Katsman, Regina; Agnon, Amotz; Ben Avraham, Zvi

2016-04-01

Understanding the role of the dynamics of water bodies in triggering deformations in the upper crust and subsequently leading to earthquakes has been attracting considerable attention. We suggest that dynamic changes in the levels of the water bodies occupying tectonic depressions along the Dead Sea Transform (DST) cause significant variations in the shallow crustal stress field and affect local fault systems in a way that eventually leads to earthquakes. This mechanism and its spatial and temporal scales differ from those in tectonically-driven deformations. In this study we present a new thermo-mechanical model, constructed using the finite element method, and extended by including a fluid flow component in the upper crust. The latter is modeled on a basis of two-way poroelastic coupling with the momentum equation. This coupling is essential for capturing fluid flow evolution induced by dynamic water loading in the DST depressions and to resolve porosity changes. All the components of the model, namely elasticity, creep, plasticity, heat transfer, and fluid flow, have been extensively verified and presented in the study. The two-way coupling between localized plastic volumetric deformations and enhanced fluid flow is addressed, as well as the role of variability of the rheological and the hydrological parameters in inducing deformations in specific faulting environments. Correlations with historical and contemporary earthquakes in the region are discussed.

Enhydrina schistosa (Elapidae: Hydrophiinae) the most dangerous sea snake in Sri Lanka: three case studies of severe envenoming.

PubMed

Kularatne, S A M; Hettiarachchi, R; Dalpathadu, J; Mendis, A S V; Appuhamy, P D S A N; Zoysa, H D J; Maduwage, K; Weerasinghe, V S; de Silva, A

2014-01-01

Sea snakes are highly venomous and inhabit tropical waters of the Indian and Pacific Oceans. Enhydrina schistosa is a common species of sea snake that lives in the coastal waters, lagoons, river mouths and estuaries from the Persian Gulf through Sri Lanka and to Southeast Asia. It is considered one of the most aggressive sea snakes in Sri Lanka where fishermen and people wading are at high risk. However, sea snake bites are rarely reported. In this report, we describe three cases where E. schistosa was the offending species. These three patients presented to two hospitals on the west coast of Sri Lanka within the course of 14 months from November 2011 with different degrees of severity of envenoming. The first patient was a 26-year-old fisherman who developed severe myalgia with very high creatine kinase (CK) levels lasting longer than 7 days. The second patient was a 32-year-old fisherman who developed gross myoglobinuria, high CK levels and hyperkalaemia. Both patients recovered and their electromyographic recordings showed myopathic features. The nerve conduction and neuromuscular transmission studies were normal in both patients suggesting primary myotoxic envenoming. The third patient was a 41-year-old man who trod on a sea snake in a river mouth and developed severe myalgia seven hours later. He had severe rhabdomyolysis and died three days later due to cardiovascular collapse. In conclusion, we confirm that E. schistosa is a deadly sea snake and its bite causes severe rhabdomyolysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

Echinoid bioerosion and herbivory on Kenyan coral reefs: the role of protection from fishing.

PubMed

Carreiro-Silva, M; McClanahan, T R.

2001-07-30

During feeding, echinoids remove a large proportion of calcium carbonate in addition to the algae growing on dead coral and are consequently of importance in estimating the turnover of organic and inorganic carbon in coral reefs. Rates of herbivory and the erosion of dead coral substratum, referred to as bioerosion, by the most abundant echinoid species in Kenyan reefs, Echinothrix diadema (Linnaeus), Diadema setosum (Leske), D. savignyi (Michelin) and Echinometra mathaei (de Blainville), were compared in three different reef categories with different histories of fishing and its exclusion. These were reefs: (i) protected within Marine National Parks, which exclude all forms of fishing, coral and shell collection for more than 25 years; (ii) one reef within a Marine Park, which has received protection from fishing activities for 8 years (referred to as 'newly protected' reef); and (iii) unprotected reefs, which experience heavy fishing and some coral collection. The aim was to investigate the grazing and bioerosion activity by the above echinoid species in these reef categories. We surveyed sea urchin population densities and determined their rates of bioerosion and herbivory per individual and square meter. Individual rates of bioerosion and herbivory, of the species D. setosum, D. savignyi and E. diadema were estimated from laboratory gut content analysis and gut evacuation experiments in the field, using elevated underwater cages. Individual rates of bioerosion and herbivory of E. mathaei were obtained from a previous field study [J. Exp. Mar. Biol. Ecol. 147 (1991) 121]. Sea urchin bioerosion was greater than herbivory for all studied species and proportional to the body size of the sea urchin species. The large-bodied E. diadema exhibited the highest bioerosion and herbivory rates (5.5+/-0.9 and 2.2+/-0.3 g individual(-1) day(-1), respectively) followed by D. setosum (1.8+/-0.3 and 1.1+/-0.2 g individual(-1) day(-1)) and D. savignyi (0.7+/-0.2 and 0.4+/-0.1 g individual(-1) day(-1)). Highest sea urchin densities were recorded at unprotected reefs (6.2+/-1.5 individual m(-2)), and therefore, bioerosion and herbivory by sea urchins were also highest in this reef category (1180+/-230 g CaCO(3) m(-2) year(-1) and 450+/-77 g algae m(-2) year(-1)). Protected reefs recorded 20 times lower sea urchin bioerosion and herbivory rates (50.3+/-25.8 g CaCO(3) m(-2) year(-1) and 20.7+/-10.4 g algae m(-2) year(-1)), due to the low sea urchin population densities in these reefs (0.06+/-0.01 individual m(-2)). The newly protected reef, with intermediate number of sea urchins (1.2+/-0.1 individual m(-2)), had intermediate rates of sea urchin bioerosion and herbivory (711+/-157 g CaCO(3) m(-2) year(-1) and 299+/-63 g algae m(-2) year(-1)). These findings suggest that echinoids are important in the carbon cycle and reef development, and that fishing can influence these ecological processes.

Detection of Rossby Waves in Multi-Parameters in Multi-Mission Satellite Observations and HYCOM Simulations in the Indian Ocean

NASA Technical Reports Server (NTRS)

Subrahmanyam, Bulusu; Heffner, David M.; Cromwell, David; Shriver, Jay F.

2009-01-01

Rossby waves are difficult to detect with in situ methods. However, as we show in this paper, they can be clearly identified in multi-parameters in multi-mission satellite observations of sea surface height (SSH), sea surface temperature (SST) and ocean color observations of chlorophyll-a (chl-a), as well as 1/12-deg global HYbrid Coordinate Ocean Model (HYCOM) simulations of SSH, SST and sea surface salinity (SSS) in the Indian Ocean. While the surface structure of Rossby waves can be elucidated from comparisons of the signal in different sea surface parameters, models are needed to gain direct information about how these waves affect the ocean at depth. The first three baroclinic modes of the Rossby waves are inferred from the Fast Fourier Transform (FFT), and two-dimensional Radon Transform (2D RT). At many latitudes the first and second baroclinic mode Rossby wave phase speeds from satellite observations and model parameters are identified.

A group filter algorithm for sea mine detection

NASA Astrophysics Data System (ADS)

Cobb, J. Tory; An, Myoung; Tolimieri, Richard

2005-06-01

Automatic detection of sea mines in coastal regions is a difficult task due to the highly variable sea bottom conditions present in the underwater environment. Detection systems must be able to discriminate objects which vary in size, shape, and orientation from naturally occurring and man-made clutter. Additionally, these automated systems must be computationally efficient to be incorporated into unmanned underwater vehicle (UUV) sensor systems characterized by high sensor data rates and limited processing abilities. Using noncommutative group harmonic analysis, a fast, robust sea mine detection system is created. A family of unitary image transforms associated to noncommutative groups is generated and applied to side scan sonar image files supplied by Naval Surface Warfare Center Panama City (NSWC PC). These transforms project key image features, geometrically defined structures with orientations, and localized spectral information into distinct orthogonal components or feature subspaces of the image. The performance of the detection system is compared against the performance of an independent detection system in terms of probability of detection (Pd) and probability of false alarm (Pfa).

SeaMARC II mapping of transform faults in the Cayman Trough, Caribbean Sea

USGS Publications Warehouse

Rosencrantz, Eric; Mann, Paul

1992-01-01

SeaMARC II maps of the southern wall of the Cayman Trough between Honduras and Jamaica show zones of continuous, well-defined fault lineaments adjacent and parallel to the wall, both to the east and west of the Cayman spreading axis. These lineaments mark the present, active traces of transform faults which intersect the southern end of the spreading axis at a triple junction. The Swan Islands transform fault to the west is dominated by two major lineaments that overlap with right-stepping sense across a large push-up ridge beneath the Swan Islands. The fault zone to the east of the axis, named the Walton fault, is more complex, containing multiple fault strands and a large pull-apart structure. The Walton fault links the spreading axis to Jamaican and Hispaniolan strike-slip faults, and it defines the southern boundary of a microplate composed of the eastern Cayman Trough and western Hispaniola. The presence of this microplate raises questions about the veracity of Caribbean plate velocities based primarily on Cayman Trough opening rates.

Irregular earthquake recurrence patterns and slip variability on a plate-boundary Fault

NASA Astrophysics Data System (ADS)

Wechsler, N.; Rockwell, T. K.; Klinger, Y.

2015-12-01

The Dead Sea fault in the Levant represents a simple, segmented plate boundary from the Gulf of Aqaba northward to the Sea of Galilee, where it changes its character into a complex plate boundary with multiple sub-parallel faults in northern Israel, Lebanon and Syria. The studied Jordan Gorge (JG) segment is the northernmost part of the simple section, before the fault becomes more complex. Seven fault-crossing buried paleo-channels, offset by the Dead Sea fault, were investigated using paleoseismic and geophysical methods. The mapped offsets capture the long-term rupture history and slip-rate behavior on the JG fault segment for the past 4000 years. The ~20 km long JG segment appears to be more active (in term of number of earthquakes) than its neighboring segments to the south and north. The rate of movement on this segment varies considerably over the studied period: the long-term slip-rate for the entire 4000 years is similar to previously observed rates (~4 mm/yr), yet over shorter time periods the rate varies from 3-8 mm/yr. Paleoseismic data on both timing and displacement indicate a high COV >1 (clustered) with displacement per event varying by nearly an order of magnitude. The rate of earthquake production does not produce a time predictable pattern over a period of 2 kyr. We postulate that the seismic behavior of the JG fault is influenced by stress interactions with its neighboring faults to the north and south. Coulomb stress modelling demonstrates that an earthquake on any neighboring fault will increase the Coulomb stress on the JG fault and thus promote rupture. We conclude that deriving on-fault slip-rates and earthquake recurrence patterns from a single site and/or over a short time period can produce misleading results. The definition of an adequately long time period to resolve slip-rate is a question that needs to be addressed and requires further work.

Radiographic features of the limbs of juvenile and subadult loggerhead sea turtles (Caretta caretta)

PubMed Central

Valente, Ana Luisa; Marco, Ignasi; Zamora, Maria Angeles; Parga, Maria Luz; Lavín, Santiago; Alegre, Ferran; Cuenca, Rafaela

2007-01-01

This study aimed to provide the normal radiographic anatomic appearance of the limbs of the loggerhead sea turtle, Caretta caretta. Dorsopalmar and dorsoplantar radiographs were taken of the forelimbs and hindlimbs of 15 juvenile and 15 subadult loggerhead sea turtles, 17 alive and 13 dead. For comparison, computed tomographic, gross anatomic, osteologic, and histologic studies were performed on the limbs of 5 of the sea turtles. Bones from the distal part of the fore and hind flippers were seen in detail with a mammographic film–screen combination. The pectoral and pelvic girdles, superimposed by the carapace, were better seen on standard radiographs with the use of rare-earth intensifying screens. Mammographic radiographs of the manus of 5 small juvenile turtles showed active growth zones. Visualization of bone contours in the distal part of the limbs was clearer than in mammals owing to the very few superimpositions. The presence of a substantial amount of cartilage in the epiphyses produced better visibility of limb ends. We conclude that use of a mammography film–screen combination is the best way to evaluate the bony and joint structures of the limbs of sea turtles. Radiography provides reliable images for clinical purposes. Considering the low cost and logistics of this technique, it is a practical ancillary test for marine animal rehabilitation centers to use. PMID:17955906

Lead exposure in raptors from Japan and source identification using Pb stable isotope ratios.

PubMed

Ishii, Chihiro; Nakayama, Shouta M M; Ikenaka, Yoshinori; Nakata, Hokuto; Saito, Keisuke; Watanabe, Yukiko; Mizukawa, Hazuki; Tanabe, Shinsuke; Nomiyama, Kei; Hayashi, Terutake; Ishizuka, Mayumi

2017-11-01

Lead (Pb) poisoning is widespread among raptors and water birds. In Japan, fragments of Pb ammunition are still found in endangered eagles although more than 10 years have passed since legislation regarding use of Pb ammunition was introduced. This study was performed to investigate Pb exposure in raptors from various locations in Japan. We measured hepatic and renal Pb concentrations and hepatic Pb isotope ratios of Steller's sea eagles (Haliaeetus pelagicus), white-tailed sea eagles (Haliaeetus albicilla), golden eagles (Aquila chrysaetos), and 13 other species (total 177 individuals) that were found dead, as well as blood samples from three eagles found in a weakened state during 1993-2015 from Hokkaido (northern part), Honshu (the main island), and Shikoku (a southern island) of Japan. In the present study in Hokkaido, one quarter of the sea eagles showed a high Pb concentration, suggesting exposure to abnormally high Pb levels and Pb poisoning. Pb isotope ratios indicated that endangered Steller's sea eagle and white-tailed sea eagle were poisoned by Pb ammunition that was used illegally in Hokkaido. In other areas of Japan, both surveillance and regulations were less extensive than in Hokkaido, but Pb poisoning in raptors was also noted. Therefore, Pb poisoning is still a serious problem in raptors in various areas of Japan due to accidental ingestion of materials containing Pb, especially Pb ammunition. Copyright © 2017. Published by Elsevier Ltd.

Keeping patients safe: Institute of Medicine looks at transforming nurses' work environment.

PubMed

2004-01-01

In November 1999, the Institute of Medicine (IOM) released To Err Is Human: Building a Safer Health System, which brought to the public's attention the serious--and sometimes deadly--dangers posed by medical errors occurring in healthcare organizations. Exactly 4 years later, an IOM committee released a new report that focuses on the need to reinforce patient safety defenses in the nurses' working environments.

Maternal transfer and sublethal immune system effects of brevetoxin exposure in nesting loggerhead sea turtles (Caretta caretta) from western Florida.

PubMed

Perrault, Justin R; Bauman, Katherine D; Greenan, Taylor M; Blum, Patricia C; Henry, Michael S; Walsh, Catherine J

2016-11-01

Blooms of Karenia brevis (also called red tides) occur almost annually in the Gulf of Mexico. The health effects of the neurotoxins (i.e., brevetoxins) produced by this toxic dinoflagellate on marine turtles are poorly understood. Florida's Gulf Coast represents an important foraging and nesting area for a number of marine turtle species. Most studies investigating brevetoxin exposure in marine turtles thus far focus on dead and/or stranded individuals and rarely examine the effects in apparently "healthy" free-ranging individuals. From May-July 2014, one year after the last red tide bloom, we collected blood from nesting loggerhead sea turtles (Caretta caretta) on Casey Key, Florida USA. These organisms show both strong nesting and foraging site fidelity. The plasma was analyzed for brevetoxin concentrations in addition to a number of health and immune-related parameters in an effort to establish sublethal effects of this toxin. Lastly, from July-September 2014, we collected unhatched eggs and liver and yolk sacs from dead-in-nest hatchlings from nests laid by the sampled females and tested these samples for brevetoxin concentrations to determine maternal transfer and effects on reproductive success. Using a competitive enzyme-linked immunosorbent assay (ELISA), all plasma samples from nesting females tested positive for brevetoxin (reported as ng brevetoxin-3[PbTx-3] equivalents [eq]/mL) exposure (2.1-26.7ng PbTx-3eq/mL). Additionally, 100% of livers (1.4-13.3ng PbTx-3eq/mL) and yolk sacs (1.7-6.6ng PbTx-3eq/mL) from dead-in-nest hatchlings and 70% of eggs (<1.0-24.4ng PbTx-3eq/mL) tested positive for brevetoxin exposure with the ELISA. We found that plasma brevetoxin concentrations determined by an ELISA in nesting females positively correlated with gamma-globulins, indicating a potential for immunomodulation as a result of brevetoxin exposure. While the sample sizes were small, we also found that plasma brevetoxin concentrations determined by an ELISA in nesting females significantly correlated with liver brevetoxin concentrations of dead-in-nest hatchlings and that brevetoxins could be related to a decreased reproductive success in this species. This study suggests that brevetoxins can still elicit negative effects on marine life long after a bloom has dissipated. These results improve our understanding of maternal transfer and sublethal effects of brevetoxin exposure in marine turtles. Copyright © 2016 Elsevier B.V. All rights reserved.

Metagenomic Analysis of Genes Encoding Nutrient Cycling Pathways in the Microbiota of Deep-Sea and Shallow-Water Sponges.

PubMed

Li, Zhiyong; Wang, Yuezhu; Li, Jinlong; Liu, Fang; He, Liming; He, Ying; Wang, Shenyue

2016-12-01

Sponges host complex symbiotic communities, but to date, the whole picture of the metabolic potential of sponge microbiota remains unclear, particularly the difference between the shallow-water and deep-sea sponge holobionts. In this study, two completely different sponges, shallow-water sponge Theonella swinhoei from the South China Sea and deep-sea sponge Neamphius huxleyi from the Indian Ocean, were selected to compare their whole symbiotic communities and metabolic potential, particularly in element transformation. Phylogenetically diverse bacteria, archaea, fungi, and algae were detected in both shallow-water sponge T. swinhoei and deep-sea sponge N. huxleyi, and different microbial community structures were indicated between these two sponges. Metagenome-based gene abundance analysis indicated that, though the two sponge microbiota have similar core functions, they showed different potential strategies in detailed metabolic processes, e.g., in the transformation and utilization of carbon, nitrogen, phosphorus, and sulfur by corresponding microbial symbionts. This study provides insight into the putative metabolic potentials of the microbiota associated with the shallow-water and deep-sea sponges at the whole community level, extending our knowledge of the sponge microbiota's functions, the association of sponge- microbes, as well as the adaption of sponge microbiota to the marine environment.

Sarcocystis neurona retinochoroiditis in a sea otter (Enhydra lutris kenyoni)

USGS Publications Warehouse

Dubey, J.P.; Thomas, N.J.

2011-01-01

Sarcocystis neurona is an important cause of fatal disease in sea otters in the USA. Encephalitis is the predominant lesion and parasites are confined to the central nervous system and muscles. Here we report retinochoroiditis in a sea otter (Enhydra lutris kenyoni) found dead on Copalis Beach, WA, USA. Salient lesions were confined to the brain and eye. Multifocal nonsuppurative meningoencephalitis was present in the cerebrum and cerebellum associated with S. neurona schizonts. The retina of one eye had a focus of inflammation that contained numerous S. neurona schizonts and merozoites. The focus extended from the retinal pigment epithelium inward through all layers of the retina, but inflammation was most concentrated at the inner surface of the tapetum and the outer retina. The inner and outer nuclear layers of the retina were disorganized and irregular at the site of inflammation. There was severe congestion and mild hemorrhage in the choroid, and mild hemorrhage into the vitreous body. Immunohistochemistry with S. neurona-specific polyclonal rabbit antibodies stained schizonts and merozoites. To our knowledge this is the first report of S. neurona-associated retinochoroiditis in any naturally infected animal.

Revisiting Seafloor-Spreading in the Red Sea: Basement Nature, Transforms and Ocean-Continent Boundary

NASA Astrophysics Data System (ADS)

Tapponnier, P.; Dyment, J.; Zinger, M. A.; Franken, D.; Afifi, A. M.; Wyllie, A.; Ali, H. G.; Hanbal, I.

2013-12-01

A new marine geophysical survey on the Saudi Arabian side of the Red Sea confirms early inferences that ~ 2/3 of the eastern Red Sea is floored by oceanic crust. Most seismic profiles south of 24°N show a strongly reflective, landward-deepening volcanic basement up to ~ 100 km east of the axial ridge, beneath thick evaporitic deposits. This position of the Ocean-Continent Boundary (OCB) is consistent with gravity measurements. The low amplitudes and long wavelengths of magnetic anomalies older than Chrons 1-3 can be accounted for by low-pass filtering due to thick sediments. Seafloor-spreading throughout the Red Sea started around 15 Ma, as in the western Gulf of Aden. Its onset was coeval with the activation of the Aqaba/Levant transform and short-cutting of the Gulf of Suez. The main difference between the southern and northern Red Sea lies not in the nature of the crust but in the direction and modulus of the plate motion rate. The ~ 30° counterclockwise strike change and halving of the spreading rate (~ 16 to ~ 8 mm/yr) between the Hermil (17°N) and Suez triple junctions results in a shift from slow (≈ North Atlantic) to highly oblique, ultra-slow (≈ Southwest Indian) ridge type. The obliquity of spreading in the central and northern basins is taken up by transform discontinuities that stop ~ 40 km short of the coastline, at the OCB. Three large transform fault systems (Jeddah, Zabargad, El Akhawein) nucleated as continental transfer faults reactivating NNE-trending Proterozoic shear zones. The former two systems divide the Red Sea into three main basins. Between ~15 and ~5 Ma, for about 10 million years, thick evaporites were deposited directly on top of oceanic crust in deep water, as the depositional environment, modulated by climate, became restricted by the Suez and Afar/Bab-el-Mandeb volcano-tectonic 'flood-gates.' The presence of these thick deposits (up to ~ 8 km) suffices to account for the difference between the Red Sea and the Gulf of Aden. Widespread salt tectonics was triggered by the flow of large evaporite sheets and salt glaciers toward the ridge axis. Such flow was more pervasive in the north, where slower spreading resulted in a deeper trough, and was guided by the rugged topography of the oceanic seafloor. The Red Sea may represent the best model for comparably deep evaporitic basins along the Earth's passive margins, particularly in the South Atlantic.

Downstream migration of recently transformed sea lampreys before and after treatment of a Lake Michigan tributary with a lampricide

USGS Publications Warehouse

Hodges, John W.

1972-01-01

After the Pere Marquette River was treated with a lampricide in May 1964, the number of recently transformed sea lampreys (Petromyzon marinus) collected in the water-intake structure of a chemical plant near the mouth of the stream dropped 99.5%, from 13,913 (average for 1962-63 and 1963-64) to 76 (average for the next four migration seasons). Average length of the lampreys caught increased markedly after the treatment. In five of the six migration seasons, the catch of downstream migrants was higher in the fall than in the spring.

Transforming Undergraduate Research Opportunities Using Telepresence

ERIC Educational Resources Information Center

Pallant, Amy; McIntyre, Cynthia; Stephens, A. Lynn

2016-01-01

The National Science Foundation funded the "Transforming Remotely Conducted Research through Ethnography, Education, and Rapidly Evolving Technologies" (TREET) project to explore ways to utilize advances in technology and thus to provide opportunities for scientists and undergraduate students to engage in deep sea research. The…

Tobacco control, stigma, and public health: rethinking the relations.

PubMed

Bayer, Ronald; Stuber, Jennifer

2006-01-01

The AIDS epidemic has borne witness to the terrible burdens imposed by stigmatization and to the way in which marginalization could subvert the goals of HIV prevention. Out of that experience, and propelled by the linkage of public health and human rights, came the commonplace assertion that stigmatization was a retrograde force.Yet, strikingly, the antitobacco movement has fostered a social transformation that involves the stigmatization of smokers. Does this transformation represent a troubling outcome of efforts to limit tobacco use and its associated morbidity and mortality; an ineffective, counterproductive, and moralizing approach that leads to a dead end; or a signal of public health achievement? If the latter is the case, are there unacknowledged costs?

Effects of wildfire on sea otter (Enhydra lutris) gene transcript profiles

USGS Publications Warehouse

Bowen, Lizabeth; Miles, A. Keith; Kolden, Crystal A.; Saarinen, Justin A.; Bodkin, James L.; Murray, Michael J.; Tinker, M. Tim

2015-01-01

Wildfires have been shown to impact terrestrial species over a range of temporal scales. Little is known, however, about the more subtle toxicological effects of wildfires, particularly in downstream marine or downwind locations from the wildfire perimeter. These down-current effects may be just as substantial as those effects within the perimeter. We used gene transcription technology, a sensitive indicator of immunological perturbation, to study the effects of the 2008 Basin Complex Fire on the California coast on a sentinel marine species, the sea otter (Enhydra lutris). We captured sea otters in 2008 (3 mo after the Basin Complex Fire was controlled) and 2009 (15 mo after the Basin Complex Fire was controlled) in the adjacent nearshore environment near Big Sur, California. Gene responses were distinctly different between Big Sur temporal groups, signifying detoxification of PAHs, possible associated response to potential malignant transformation, and suppression of immune function as the primary responses of sea otters to fire in 2008 compared to those captured in 2009. In general, gene transcription patterns in the 2008 sea otters were indicative of molecular reactions to organic exposure, malignant transformation, and decreased ability to respond to pathogens that seemed to consistent with short-term hydrocarbon exposure.

Continuous Wavelet Transform Analysis of Acceleration Signals Measured from a Wave Buoy

PubMed Central

Chuang, Laurence Zsu-Hsin; Wu, Li-Chung; Wang, Jong-Hao

2013-01-01

Accelerometers, which can be installed inside a floating platform on the sea, are among the most commonly used sensors for operational ocean wave measurements. To examine the non-stationary features of ocean waves, this study was conducted to derive a wavelet spectrum of ocean waves and to synthesize sea surface elevations from vertical acceleration signals of a wave buoy through the continuous wavelet transform theory. The short-time wave features can be revealed by simultaneously examining the wavelet spectrum and the synthetic sea surface elevations. The in situ wave signals were applied to verify the practicality of the wavelet-based algorithm. We confirm that the spectral leakage and the noise at very-low-frequency bins influenced the accuracies of the estimated wavelet spectrum and the synthetic sea surface elevations. The appropriate thresholds of these two factors were explored. To study the short-time wave features from the wave records, the acceleration signals recorded from an accelerometer inside a discus wave buoy are analysed. The results from the wavelet spectrum show the evidence of short-time nonlinear wave events. Our study also reveals that more surface profiles with higher vertical asymmetry can be found from short-time nonlinear wave with stronger harmonic spectral peak. Finally, we conclude that the algorithms of continuous wavelet transform are practical for revealing the short-time wave features of the buoy acceleration signals. PMID:23966188

Aphanius kruppi, a new killifish from Oman with comments on the A. dispar species group (Cyprinodontiformes: Aphaniidae).

PubMed

Freyhof, Jörg; Weissenbacher, Anton; Geiger, Matthias

2017-10-26

Eight species are recognised in the Aphanius dispar group. Aphanius dispar from the Red and Mediterranean Sea basins, A. stoliczkanus from coastal areas of the Arabian/Persian Gulf, the northern Arabian Sea east to Gujarat in India, the Gulf of Oman and some endorheic basins in Iran and Pakistan, A. richardsoni from springs in the Dead Sea basin in Jordan and Israel, A. sirhani from the Azraq Oasis in Jordan, A. ginaonis from one spring in Iran, A. furcatus from few streams and springs in Iran and A. stiassnyae from one lake in Ethiopia. Aphanius kruppi, new species, from the Wadi al Batha drainage in northern Oman, is distinguished from adjacent A. stoliczkanus by having 9-14 brown or grey lateral bars on the flank in the male, a roundish, diamond-shaped or somewhat vertically-elongate blotch centred on the caudal-fin base in the female and 2-3 scale rows on the caudal-fin base. The available molecular genetic data for A. dispar reject the hypothesis of the presence of a single widespread coastal species in the Middle East and make it likely that two additional unidentified species occur in the Red Sea basin.

The epizootiology of type C botulism in fish-eating birds at Salton Sea, California

USGS Publications Warehouse

Nol, P.

2002-01-01

During 1996, type C avian botulism killed over 15,000 fish-eating birds at the Salton Sea in southern California. Amont those affected were nearly 10,000 western white pelicans (Pelecanus erythrorhynchos) and over 1,200 endangered California brown pelicans (Pelecanus occidentalis californicus). Since 1996, smaller epizootics have occurred every year. Type C botulism is not typically associated with fish-eating birds. In the case of the Salton Sea, Mozambique tilapia (Oreochromis mossambicus) are the suspected source of type C toxin, although the mechanism by which the fish acquire the toxin is still unknown. The goals of this study were to: 1) Determine presence/absence of active Clostridium botulinum type C and type C botulinum toxin in tilapia in the Salton Sea. 2) Use geospatial analyses to evaluate relationships between patterns of mortality in birds and fish and presence/absence of toxin and/or toxin-producing bacteria in sediments and fish. We investigated a method of detecting C. botulinum type C cells in the intestinal contents of Mozambique tilapia. This method involved extraction of predominantly cellular DNA and uses a polymerase chain reaction assay to detect presence of type C toxin gene. We collected sick, dead and healthy fish from various sites throughout the Sea during the summers of 1999 to 2001 in order to test them for the presence of active C. botulinum type C by PCR and for the presence of type C toxin by ELISA and mouse test. The results demonstrate that the tilapia population in the Salton Sea harbors C. botulinum type C cells within their gastrointestinal tract and the prevalence of this organism varies from year to year. The total number of fish with toxin-producing bacteria was significantly greater in 2000 than in 2001. No difference in the numbers of positives was detected between sick and dead fish compared to live fish, and there were no differences noted with regard to location of fish collection. The prevalence of active type C toxin in tilapia was low and the majority of samples positive for toxin by ELISA were negative on mouse test. Further investigation is currently underway. From 1999-2001, routine surveillance was conducted July through November to detect morbidity and mortality in pelicans. Location of retrieval and total number of birds collected were documented. In all three years, the majority of botulism-affected pelicans were retrieved from the vicinities of the river deltas although the Whitewater River had the fewest birds of the three. It has yet to be determined what roles the tilapia and pelican populations play in influencing these patterns.

Killing the dead: chemotherapeutic strategies against free-living cyst-forming protists (Acanthamoeba sp. and Balamuthia mandrillaris).

PubMed

Siddiqui, Ruqaiyyah; Aqeel, Yousuf; Khan, Naveed Ahmed

2013-01-01

The opportunist free-living protists such as Acanthamoeba spp. and Balamuthia mandrillaris have become a serious threat to human life. As most available drugs target functional aspects of pathogens, the ability of free-living protists to transform into metabolically inactive cyst forms presents a challenge in treatment. It is hoped, that the development of broad spectrum antiprotist agents acting against multiple cyst-forming protists to provide target-directed inhibition will offer a viable drug strategy in the treatment of these rare infections. Here, we present a comprehensive report on upcoming drug targets, with emphasis on cyst wall biosynthesis along with the related biochemistry of encystment pathways, as we strive to bring ourselves a step closer to being able to combat these deadly diseases. © 2013 The Author(s) Journal of Eukaryotic Microbiology © 2013 International Society of Protistologists.

Sex ratio estimations of loggerhead sea turtle hatchlings by histological examination and nest temperatures at Fethiye beach, Turkey

NASA Astrophysics Data System (ADS)

Kaska, Yakup; Ilgaz, Çetin; Özdemir, Adem; Başkale, Eyüp; Türkozan, Oğuz; Baran, Ibrahim; Stachowitsch, Michael

2006-07-01

Hatchling sex ratios in the loggerhead turtle ( Caretta caretta) were estimated by placing electronic temperature recorders in 21 nests at Fethiye beach during 2000 2002. Over the seasons, the mean temperature in the middle third of the incubation period ranged from 26.7 to 32.1°C, and incubation periods ranged from 49 to 67 days. Based on the mean temperatures during the middle third of the incubation period, and on histologically sexed dead hatchlings, the sex ratios of hatchlings at Fethiye beach were roughly equal, i.e. 60 65% of the hatchlings were females. This contrasts with the highly female-skewed sex ratios in loggerhead turtles elsewhere; Fethiye has a relatively high proportion of male hatchlings. For endangered sea turtles, the knowledge of hatchling sex ratios at different beaches, coupled with appropriate conservation measures, can make an important contribution to their survival.

Anatomy of ridge discontinuities, transform fault and overlapping spreading centre, at the slow spreading sedimented Andaman Sea Spreading Centre

NASA Astrophysics Data System (ADS)

Jourdain, A.; Singh, S. C.; Klinger, Y.

2013-12-01

Transform faults are the major discontinuities and define the main segment boundaries along spreading centres but their anatomy is poorly understood because of their complex seafloor morphology, even though they are observed at all types of spreading centres. Here, we present high-resolution seismic reflection images across the sedimented Andaman Sea Transform Fault where the sediments record the faulting and allow studying the evolution of the transform fault both in space and time. Furthermore, sediments allow the imaging of the faults down to the Moho depth that provides insight on the interplay between tectonic and magmatic processes. On the other hand, overlapping spreading centres (OSC) are small-scale discontinuities, possibly transient, and are observed only along fast or intermediate spreading centres. Exceptionally, an overlapping spreading centre is present at the slow spreading Andaman Sea Spreading Centre, which, we suggest, is due to the presence of thick sediments that hamper the efficient hydrothermal circulation allowing magma to stay much longer in the crust at different depths, and up to close to the segment ends, leading to the development of an overlapping spreading. The seismic reflection images across the OSC indicate the presence of large magma bodies in the crust. Seismic images also provide images of active faults allowing to study the link between faulting and magmatism. Interestingly, an earthquake swarm occurred at propagating limb of the OSC in 2006, after the great 2004 Andaman-Sumatra earthquake of Mw=9.3, highlighting the migration of the OSC westward. In this paper, we will show seismic reflection images and interpret these images in the light of bathymetry and earthquake data, and provide the anatomy of the ridge discontinuities along the slow spreading sedimented Andaman Sea Spreading Centre.

A High-Resolution Model of Water Mass Transformation and Transport in the Weddell Sea

NASA Astrophysics Data System (ADS)

Hazel, J.; Stewart, A.

2016-12-01

The ocean circulation around the Antarctic margins has a pronounced impact on the global ocean and climate system. One of these impacts includes closing the global meridional overturning circulation (MOC) via formation of dense Antarctic Bottom Water (AABW), which ventilates a large fraction of the subsurface ocean. AABW is also partially composed of modified Circumpolar Deep Water (CDW), a warm, mid-depth water mass whose transport towards the continent has the potential to induce rapid retreat of marine-terminating glaciers. Previous studies suggest that these water mass exchanges may be strongly influenced by high-frequency processes such as downslope gravity currents, tidal flows, and mesoscale/submesoscale eddy transport. However, evaluating the relative contributions of these processes to near-Antarctic water mass transports is hindered by the region's relatively small scales of motion and the logistical difficulties in taking measurements beneath sea ice.In this study we develop a regional model of the Weddell Sea, the largest established source of AABW. The model is forced by an annually-repeating atmospheric state constructed from the Antarctic Mesoscale Prediction System data and by annually-repeating lateral boundary conditions constructed from the Southern Ocean State Estimate. The model incorporates the full Filchner-Ronne cavity and simulates the thermodynamics and dynamics of sea ice. To analyze the role of high-frequency processes in the transport and transformation of water masses, we compute the model's overturning circulation, water mass transformations, and ice sheet basal melt at model horizontal grid resolutions ranging from 1/2 degree to 1/24 degree. We temporally decompose the high-resolution (1/24 degree) model circulation into components due to mean, eddy and tidal flows and discuss the geographical dependence of these processes and their impact on water mass transformation and transport.

Estimation of climate change impact on dead fuel moisture at local scale by using weather generators

NASA Astrophysics Data System (ADS)

Pellizzaro, Grazia; Bortolu, Sara; Dubrovsky, Martin; Arca, Bachisio; Ventura, Andrea; Duce, Pierpaolo

2015-04-01

The moisture content of dead fuel is an important variable in fire ignition and fire propagation. Moisture exchange in dead materials is controlled by physical processes, and is clearly dependent on atmospheric changes. According to projections of future climate in Southern Europe, changes in temperature, precipitation and extreme events are expected. More prolonged drought seasons could influence fuel moisture content and, consequently, the number of days characterized by high ignition danger in Mediterranean ecosystems. The low resolution of the climate data provided by the general circulation models (GCMs) represents a limitation for evaluating climate change impacts at local scale. For this reason, the climate research community has called to develop appropriate downscaling techniques. One of the downscaling approaches, which transform the raw outputs from the climate models (GCMs or RCMs) into data with more realistic structure, is based on linking a stochastic weather generator with the climate model outputs. Weather generators linked to climate change scenarios can therefore be used to create synthetic weather series (air temperature and relative humidity, wind speed and precipitation) representing present and future climates at local scale. The main aims of this work are to identify useful tools to determine potential impacts of expected climate change on dead fuel status in Mediterranean shrubland and, in particular, to estimate the effect of climate changes on the number of days characterized by critical values of dead fuel moisture. Measurements of dead fuel moisture content (FMC) in Mediterranean shrubland were performed by using humidity sensors in North Western Sardinia (Italy) for six years. Meteorological variables were also recorded. Data were used to determine the accuracy of the Canadian Fine Fuels Moisture Code (FFM code) in modelling moisture dynamics of dead fuel in Mediterranean vegetation. Critical threshold values of FFM code for Mediterranean climate were identified by percentile analysis, and new fuel moisture code classes were also defined. A stochastic weather generator (M&Rfi), linked to climate change scenarios derived from 17 available General Circulation Models (GCMs), was used to produce synthetic weather series, representing present and future climates, for four selected sites located in North Western Sardinia, Italy. The number of days with critical FFM code values for present and future climate were calculated and the potential impact of future climate change was analysed.

Sinkhole formation and subsidence along the Dead Sea coast, Israel

NASA Astrophysics Data System (ADS)

Yechieli, Yoseph; Abelson, Meir; Baer, Gideon

2016-05-01

More than 4,000 sinkholes have formed since the 1980s within a 60-km-long and 1-km-wide strip along the western coast of the Dead Sea (DS) in Israel. Their formation rate accelerated in recent years to >400 sinkholes per year. They cluster mostly in specific sites up to 1,000 m long and 200 m wide, which align parallel to the general direction of the fault systems associated with the DS Rift. The abrupt appearance of the sinkholes reflects changes to the groundwater regime around the shrinking DS. The eastward retreat of the shoreline and the lake-level drop (1 m/year in recent years) cause an eastward and downward migration of the fresh/saline groundwater interface. Consequently, a subsurface salt layer, which was previously enveloped by saline groundwater, is gradually being invaded and submerged by relatively fresh groundwater, and cavities form due to the rapid dissolution of the salt. Collapse of the overlying sediments into these cavities results in sinkholes at the surface. An association between sinkhole sites and land subsidence is revealed by interferometric synthetic aperture radar (InSAR) measurements. On a broad scale (hundreds of meters), subsidence occurs due to compaction of fine-grained sediments as groundwater levels decline along the retreating DS shoreline. At smaller scales (tens of meters), subsidence appears above subsurface cavities in association with the sinkholes, serving in many cases as sinkhole precursors, a few weeks to more than a year before their actual appearance at the surface. This paper overviews the processes of sinkhole formation and their relation to land subsidence.

Factors controlling the configuration of the fresh-saline water interface in the Dead Sea coastal aquifers: Synthesis of TDEM surveys and numerical groundwater modeling

USGS Publications Warehouse

Yechieli, Y.; Kafri, U.; Goldman, M.; Voss, C.I.

2001-01-01

TDEM (time domain electromagnetic) traverses in the Dead Sea (DS) coastal aquifer help to delineate the configuration of the interrelated fresh-water and brine bodies and the interface in between. A good linear correlation exists between the logarithm of TDEM resistivity and the chloride concentration of groundwater, mostly in the higher salinity range, close to that of the DS brine. In this range, salinity is the most important factor controlling resistivity. The configuration of the fresh-saline water interface is dictated by the hydraulic gradient, which is controlled by a number of hydrological factors. Three types of irregularities in the configuration of fresh-water and saline-water bodies were observed in the study area: 1. Fresh-water aquifers underlying more saline ones ("Reversal") in a multi-aquifer system. 2. "Reversal" and irregular residual saline-water bodies related to historical, frequently fluctuating DS base level and respective interfaces, which have not undergone complete flushing. A rough estimate of flushing rates may be obtained based on knowledge of the above fluctuations. The occurrence of salt beds is also a factor affecting the interface configuration. 3. The interface steepens towards and adjacent to the DS Rift fault zone. Simulation analysis with a numerical, variable-density flow model, using the US Geological Survey's SUTRA code, indicates that interface steep- ening may result from a steep water-level gradient across the zone, possibly due to a low hydraulic conductivity in the immediate vicinity of the fault.

Protective effects of a cream containing Dead Sea minerals against UVB-induced stress in human skin.

PubMed

Portugal-Cohen, Meital; Soroka, Yoram; Ma'or, Zeevi; Oron, Miriam; Zioni, Tamar; Brégégère, François Menahem; Neuman, Rami; Kohen, Ron; Milner, Yoram

2009-09-01

Dead Sea (DS) mud and water are known for their unique composition of minerals, and for their therapeutic properties on psoriasis and other inflammatory skin diseases. Their mode of action, however, remains poorly known. To analyse the ability of Dermud, a leave-on skin preparation containing DS mud and other ingredients like DS water, zinc oxide, aloe-vera extract, pro-vitamin B5 and vitamin E, to antagonize biological effects induced by UVB irradiation in skin when topically applied in organ cultures. We have used human skin organ cultures as a model to assess the biological effects of UVB irradiation and of Dermud cream topical application. Skin pieces were analysed for mitochondrial activity by MTT assay, for apoptosis by caspase 3 assay, for cytokine secretion by solid phase ELISA, for overall antioxidant capacity by ferric reducing antioxidant power and Oxygen radical absorbance capacity assays (epidermis) or by cyclic voltammetry (external medium), and for uric acid (UA) content by HPLC. We report that UVB irradiation decreases cell viability, total antioxidant capacity and UA contents in the epidermis of skin organ cultures, while increasing the levels of apoptosis in cells and their cytokine secretion. Topical application of Dermud decreased all these effects significantly. Our results clearly show that Dermud has protective, anti-oxidant and anti-inflammatory properties that can antagonize biological effects of UVB irradiation in skin. It may therefore be able to reduce skin photodamage and photoaging, and more generally to reduce oxidative stress and inflammation in skin pathologies.

Anaerobic oxidation of methane by sulfate in hypersaline groundwater of the Dead Sea aquifer

PubMed Central

Avrahamov, N; Antler, G; Yechieli, Y; Gavrieli, I; Joye, S B; Saxton, M; Turchyn, A V; Sivan, O

2014-01-01

Geochemical and microbial evidence points to anaerobic oxidation of methane (AOM) likely coupled with bacterial sulfate reduction in the hypersaline groundwater of the Dead Sea (DS) alluvial aquifer. Groundwater was sampled from nine boreholes drilled along the Arugot alluvial fan next to the DS. The groundwater samples were highly saline (up to 6300 mm chlorine), anoxic, and contained methane. A mass balance calculation demonstrates that the very low δ13CDIC in this groundwater is due to anaerobic methane oxidation. Sulfate depletion coincident with isotope enrichment of sulfur and oxygen isotopes in the sulfate suggests that sulfate reduction is associated with this AOM. DNA extraction and 16S amplicon sequencing were used to explore the microbial community present and were found to be microbial composition indicative of bacterial sulfate reducers associated with anaerobic methanotrophic archaea (ANME) driving AOM. The net sulfate reduction seems to be primarily controlled by the salinity and the available methane and is substantially lower as salinity increases (2.5 mm sulfate removal at 3000 mm chlorine but only 0.5 mm sulfate removal at 6300 mm chlorine). Low overall sulfur isotope fractionation observed (34ε = 17 ± 3.5‰) hints at high rates of sulfate reduction, as has been previously suggested for sulfate reduction coupled with methane oxidation. The new results demonstrate the presence of sulfate-driven AOM in terrestrial hypersaline systems and expand our understanding of how microbial life is sustained under the challenging conditions of an extremely hypersaline environment. PMID:25039851

Anaerobic oxidation of methane by sulfate in hypersaline groundwater of the Dead Sea aquifer.

PubMed

Avrahamov, N; Antler, G; Yechieli, Y; Gavrieli, I; Joye, S B; Saxton, M; Turchyn, A V; Sivan, O

2014-11-01

Geochemical and microbial evidence points to anaerobic oxidation of methane (AOM) likely coupled with bacterial sulfate reduction in the hypersaline groundwater of the Dead Sea (DS) alluvial aquifer. Groundwater was sampled from nine boreholes drilled along the Arugot alluvial fan next to the DS. The groundwater samples were highly saline (up to 6300 mm chlorine), anoxic, and contained methane. A mass balance calculation demonstrates that the very low δ(13) CDIC in this groundwater is due to anaerobic methane oxidation. Sulfate depletion coincident with isotope enrichment of sulfur and oxygen isotopes in the sulfate suggests that sulfate reduction is associated with this AOM. DNA extraction and 16S amplicon sequencing were used to explore the microbial community present and were found to be microbial composition indicative of bacterial sulfate reducers associated with anaerobic methanotrophic archaea (ANME) driving AOM. The net sulfate reduction seems to be primarily controlled by the salinity and the available methane and is substantially lower as salinity increases (2.5 mm sulfate removal at 3000 mm chlorine but only 0.5 mm sulfate removal at 6300 mm chlorine). Low overall sulfur isotope fractionation observed ((34) ε = 17 ± 3.5‰) hints at high rates of sulfate reduction, as has been previously suggested for sulfate reduction coupled with methane oxidation. The new results demonstrate the presence of sulfate-driven AOM in terrestrial hypersaline systems and expand our understanding of how microbial life is sustained under the challenging conditions of an extremely hypersaline environment. © 2014 The Authors. Geobiology Published by John Wiley & Sons Ltd.

Rheological characterization of hair shampoo in the presence of dead sea salt.

PubMed

Abu-Jdayil, B; Mohameed, H A; Sa'id, M; Snobar, T

2004-02-01

In Jordan, a growing industry has been established to produce different types of Dead Sea (DS) cosmetics that have DS salt (contains mainly NaCl, KCl, and MgCl(2)) in their formulas. In this work, the effect of DS salt on the rheology of hair shampoo containing the sodium lauryl ether sulfate as a main active matter was studied. The effects of DS salt and active matter concentration, and the temperature and time of salt mixing, on the rheological properties of hair shampoo were investigated. The salt-free shampoo showed a Newtonian behavior at 'low active matter' (LAM) and shear thinning at 'high active matter' (HAM). The presence of DS salt changed the rheological behavior of LAM shampoo from Newtonian (for the salt-free shampoo) to shear thinning. On the other hand, the behavior of HAM shampoo switched from shear thinning to Newtonian behavior in the presence of high concentration of DS salt. The addition of DS salt increased the apparent viscosity of shampoo to reach a maximum value that corresponded to a salt concentration of 1.5 wt.%. Further addition of DS salt led to a decrease in the shampoo viscosity to reach a value less than that of the salt-free sample at high salt concentration. Changing the mixing temperature (25-45 degrees C) and mixing time (15-120 min) of DS salt with shampoo has no significant influence on the rheological behavior. However, the mixing process increased the apparent viscosity of salt-free shampoo. The power law model fitted well the flow curves of hair shampoo with and without DS salt.

Estimating parasitic sea lamprey abundance in Lake Huron from heterogenous data sources

USGS Publications Warehouse

Young, Robert J.; Jones, Michael L.; Bence, James R.; McDonald, Rodney B.; Mullett, Katherine M.; Bergstedt, Roger A.

2003-01-01

The Great Lakes Fishery Commission uses time series of transformer, parasitic, and spawning population estimates to evaluate the effectiveness of its sea lamprey (Petromyzon marinus) control program. This study used an inverse variance weighting method to integrate Lake Huron sea lamprey population estimates derived from two estimation procedures: 1) prediction of the lake-wide spawning population from a regression model based on stream size and, 2) whole-lake mark and recapture estimates. In addition, we used a re-sampling procedure to evaluate the effect of trading off sampling effort between the regression and mark-recapture models. Population estimates derived from the regression model ranged from 132,000 to 377,000 while mark-recapture estimates of marked recently metamorphosed juveniles and parasitic sea lampreys ranged from 536,000 to 634,000 and 484,000 to 1,608,000, respectively. The precision of the estimates varied greatly among estimation procedures and years. The integrated estimate of the mark-recapture and spawner regression procedures ranged from 252,000 to 702,000 transformers. The re-sampling procedure indicated that the regression model is more sensitive to reduction in sampling effort than the mark-recapture model. Reliance on either the regression or mark-recapture model alone could produce misleading estimates of abundance of sea lampreys and the effect of the control program on sea lamprey abundance. These analyses indicate that the precision of the lakewide population estimate can be maximized by re-allocating sampling effort from marking sea lampreys to trapping additional streams.

The ocean mixed layer under Southern Ocean sea-ice: Seasonal cycle and forcing

NASA Astrophysics Data System (ADS)

Pellichero, Violaine; Sallée, Jean-Baptiste; Schmidtko, Sunke; Roquet, Fabien; Charrassin, Jean-Benoît

2017-02-01

The oceanic mixed layer is the gateway for the exchanges between the atmosphere and the ocean; in this layer, all hydrographic ocean properties are set for months to millennia. A vast area of the Southern Ocean is seasonally capped by sea-ice, which alters the characteristics of the ocean mixed layer. The interaction between the ocean mixed layer and sea-ice plays a key role for water mass transformation, the carbon cycle, sea-ice dynamics, and ultimately for the climate as a whole. However, the structure and characteristics of the under-ice mixed layer are poorly understood due to the sparseness of in situ observations and measurements. In this study, we combine distinct sources of observations to overcome this lack in our understanding of the polar regions. Working with elephant seal-derived, ship-based, and Argo float observations, we describe the seasonal cycle of the ocean mixed-layer characteristics and stability of the ocean mixed layer over the Southern Ocean and specifically under sea-ice. Mixed-layer heat and freshwater budgets are used to investigate the main forcing mechanisms of the mixed-layer seasonal cycle. The seasonal variability of sea surface salinity and temperature are primarily driven by surface processes, dominated by sea-ice freshwater flux for the salt budget and by air-sea flux for the heat budget. Ekman advection, vertical diffusivity, and vertical entrainment play only secondary roles. Our results suggest that changes in regional sea-ice distribution and annual duration, as currently observed, widely affect the buoyancy budget of the underlying mixed layer, and impact large-scale water mass formation and transformation with far reaching consequences for ocean ventilation.

Influence of air-sea coupling on Indian Ocean tropical cyclones

NASA Astrophysics Data System (ADS)

Lengaigne, Matthieu; Neetu, S.; Samson, Guillaume; Vialard, Jérôme; Krishnamohan, K. S.; Masson, Sébastien; Jullien, Swen; Suresh, I.; Menkes, Christophe E.

2018-02-01

This paper assesses the impact of air-sea coupling on Indian Ocean tropical cyclones (TCs) by comparing a 20-year long simulation of a ¼° regional coupled ocean-atmosphere model with a twin experiment, where the atmospheric component is forced by sea surface temperature from the coupled simulation. The coupled simulation reproduces the observed spatio-temporal TCs distribution and TC-induced surface cooling reasonably well, but overestimates the number of TCs. Air-sea coupling does not affect the cyclogenesis spatial distribution but reduces the number of TCs by 20% and yields a better-resolved bimodal seasonal distribution in the northern hemisphere. Coupling also affects intensity distribution, inducing a four-fold decrease in the proportion of intense TCs (Cat-2 and stronger). Air-sea coupling damps TCs growth through a reduction of inner-core upward enthalpy fluxes due to the TC-induced cooling. This reduction is particularly large for the most intense TCs of the northern Indian Ocean (up to 250 W m-2), due to higher ambient surface temperatures and larger TC-induced cooling there. The negative feedback of air-sea coupling on strongest TCs is mainly associated with slow-moving storms, which spend more time over the cold wake they induce. Sensitivity experiments using a different convective parameterization yield qualitatively similar results, with a larger ( 65%) reduction in the number of TCs. Because of their relatively coarse resolution (¼°), both set of experiments however fail to reproduce the most intense observed TCs. Further studies with finer resolution models in the Bay of Bengal will be needed to assess the expectedly large impact of air-sea coupling on those intense and deadly TCs.

The contribution of apoptosis and necrosis in freezing injury of sea urchin embryonic cells.

PubMed

Boroda, Andrey V; Kipryushina, Yulia O; Yakovlev, Konstantin V; Odintsova, Nelly A

2016-08-01

Sea urchins have recently been reported to be a promising tool for investigations of oxidative stress, UV light perturbations and senescence. However, few available data describe the pathway of cell death that occurs in sea urchin embryonic cells after cryopreservation. Our study is focused on the morphological and functional alterations that occur in cells of these animals during the induction of different cell death pathways in response to cold injury. To estimate the effect of cryopreservation on sea urchin cell cultures and identify the involved cell death pathways, we analyzed cell viability (via trypan blue exclusion test, MTT assay and DAPI staining), caspase activity (via flow cytometry and spectrophotometry), the level of apoptosis (via annexin V-FITC staining), and cell ultrastructure alterations (via transmission electron microscopy). Using general caspase detection, we found that the level of caspase activity was low in unfrozen control cells, whereas the number of apoptotic cells with activated caspases rose after freezing-thawing depending on cryoprotectants used, also as the number of dead cells and cells in a late apoptosis. The data using annexin V-binding assay revealed a very high apoptosis level in all tested samples, even in unfrozen cells (about 66%). Thus, annexin V assay appears to be unsuitable for sea urchin embryonic cells. Typical necrotic cells with damaged mitochondria were not detected after freezing in sea urchin cell cultures. Our results assume that physical cell disruption but not freezing-induced apoptosis or necrosis is the predominant reason of cell death in sea urchin cultures after freezing-thawing with any cryoprotectant combination. Copyright © 2016 Elsevier Inc. All rights reserved.

Prognostic characteristics of the lowest-mode internal waves in the Sea of Okhotsk

NASA Astrophysics Data System (ADS)

Kurkin, Andrey; Kurkina, Oxana; Zaytsev, Andrey; Rybin, Artem; Talipova, Tatiana

2017-04-01

The nonlinear dynamics of short-period internal waves on ocean shelves is well described by generalized nonlinear evolutionary models of Korteweg - de Vries type. Parameters of these models such as long wave propagation speed, nonlinear and dispersive coefficients can be calculated using hydrological data (sea water density stratification), and therefore have geographical and seasonal variations. The internal wave parameters for the basin of the Sea of Okhotsk are computed on a base of recent version of hydrological data source GDEM V3.0. Geographical and seasonal variability of internal wave characteristics is investigated. It is shown that annually or seasonally averaged data can be used for linear parameters. The nonlinear parameters are more sensitive to temporal averaging of hydrological data and detailed data are preferable to use. The zones for nonlinear parameters to change their signs (so-called "turning points") are selected. Possible internal waveforms appearing in the process of internal tide transformation including the solitary waves changing polarities are simulated for the hydrological conditions in the Sea of Okhotsk shelf to demonstrate different scenarios of internal wave adjustment, transformation, refraction and cylindrical divergence.

Comparison of trace element concentrations in livers of diseased, emaciated and non-diseased southern sea otters from the California coast

USGS Publications Warehouse

Kannan, K.; Agusa, T.; Perrotta, E.; Thomas, N.J.; Tanabe, S.

2006-01-01

Infectious diseases have been implicated as a cause of high rates of adult mortality in southern sea otters. Exposure to environmental contaminants can compromise the immuno-competence of animals, predisposing them to infectious diseases. In addition to organic pollutants, certain trace elements can modulate the immune system in marine mammals. Nevertheless, reports of occurrence of trace elements, including toxic heavy metals, in sea otters are not available. In this study, concentrations of 20 trace elements (V, Cr, Mn, Co, Cu, Zn, Rb, Sr, Mo, Ag, Cd, In, Sn, Sb, Cs, Ba, Hg, Tl, Pb, and Bi) were measured in livers of southern sea otters found dead along the central California coast (n = 80) from 1992 to 2002. Hepatic concentrations of trace elements were compared among sea otters that died from infectious diseases (n = 27), those that died from non-infectious causes (n = 26), and otters that died in emaciated condition with no evidence of another cause of death (n = 27). Concentrations of essential elements in sea otters varied within an order of magnitude, whereas concentrations of non-essential elements varied by two to five orders of magnitude. Hepatic concentrations of Cu and Cd were 10- to 100-fold higher in the sea otters in this study than concentrations reported for any other marine mammal species. Concentrations of Mn, Co, Zn, and Cd were elevated in the diseased and emaciated sea otters relative to the non-diseased sea otters. Elevated concentrations of essential elements such as Mn, Zn, and Co in the diseased/emaciated sea otters suggest that induction of synthesis of metallothionein and superoxide dismutase (SOD) enzyme is occurring in these animals, as a means of protecting the cells from oxidative stress-related injuries. Trace element profiles in diseased and emaciated sea otters suggest that oxidative stress mediates the perturbation of essential-element concentrations. Elevated concentrations of toxic metals such as Cd, in addition to several other organic pollutants, may contribute to oxidative stress-meditated effects in sea otters.

Coral Microatolls and Their Role as Fixed Biological Indicators of Holocene Sea-Level Changes

NASA Astrophysics Data System (ADS)

Woodroffe, C. D.; Smithers, S. G.; McGregor, H. V.

2008-12-01

Corals microatolls are individual colonies of massive coral that have grown up to a level at which further upward growth is constrained by exposure at low tide, and which then continue to grow outwards, resulting in a flat-topped discoid morphology. Typically, microatolls comprise a single colony of massive Porites up to several metres in diameter. Modern microatolls are living on their outer margin but are predominantly dead on their upper surface. Microatolls are fixed biological sea-level indicators of the former upper limits to coral growth providing information on sea level at several temporal scales. Fossil microatolls have been used extensively to reconstruct broad patterns of Holocene sea-level trends in the Indo-Pacific reef province. Where they are preserved at a height above that of their living counterparts in the eastern Indian Ocean, Southeast Asia, northern Australia, and across much of the equatorial Pacific Ocean, they indicate that reef flats have experienced relatively higher sea levels in the mid- and late Holocene. Progressively lower corals have been interpreted to record the fall in sea level to its present position over millennial time scales. Large specimens of microatolls can reach several metres in diameter and contain a growth record of tens to hundreds of years; the upper surfaces of these can be used to track the pattern of sea-level variation over several decades. In this paper we explore the potential for using concentric annuli and subtle undulations preserved on microatoll upper surfaces to interpret sea-level changes over decadal to millennial time scales. We demonstrate that in the central Pacific modern microatolls preserve a surface morphology that reflects oscillations of sea level associated with El Niño. We evaluate the extent to which similar fluctuations may be recorded in the morphology of Indian Ocean microatolls, and the circumstances which promote the preservation of these morphological records of sea-level change over longer time scales. We discuss the potential to reconstruct extended records of sea-level change by using geochemical signatures preserved within microatoll skeletons to improve cross-correlations between colonies, and assess the precision with which sea level can be inferred.

Histopathologic lesions in sea otters exposed to crude oil

USGS Publications Warehouse

Lipscomb, T.P.; Harris, R.K.; Moeller, R.B.; Pletcher, J.M.; Haebler, R.J.; Ballachey, Brenda E.

1993-01-01

Following the Exxon Valdez oil spill in Prince William Sound, Alaska, sea otters (Enhydra lutris) that appeared to be contaminated with oil, that were in danger of becoming contaminated, or that were behaving abnormally were captured and taken to rehabilitation centers. Exposure to oil was assessed by visual examination when otters arrived at the centers. Degree of oil exposure was graded according to the following criteria: oil covering greater than 60% of the body - heavily contaminated; oil covering 30–60% of the body - moderately contaminated; oil covering less than 30% of the body or light sheen on fur - lightly contaminated. If there was no oil visible, otters were considered uncontaminated. Tissues from 51 oil-contaminated sea otters (14 males, 37 females) and from six uncontaminated sea otters (three males, three females) that died in rehabilitation centers were examined histologically. Among oil-contaminated sea otters, 19/46 had interstitial pulmonary emphysema, 13/40 had gastric erosion and hemorrhage, 11/47 had centrilobular hepatic necrosis, 14/47 had periportal to diffuse hepatic lipidosis, and 10/42 had renal tubular lipidosis. Of the uncontaminated sea otters, 1/6 had gastric erosion and hemorrhage and 1/6 had diffuse hepatic lipidosis. Histologic examinations were performed on tissues from five sea otters (three males, two females) found dead with external oil present 15 to 16 days after the spill. Periportal hepatic lipidosis and renal tubular lipidosis were found in 3/5, and interstitial pulmonary emphysema was found in 1/5. Tissues from six apparently normal sea otters (four males, two females) collected from an area not affected by an oil spill were examined histologically, and none of these lesions were found. We conclude that interstitial pulmonary emphysema, centrilobular hepatic necrosis, and hepatic and renal lipidosis of sea otters were associated with exposure to crude oil. Gastric erosion and hemorrhage may have been associated with stress of captivity and/or oil exposure.

Application of Huang-Hilbert Transforms to Geophysical Datasets

NASA Technical Reports Server (NTRS)

Duffy, Dean G.

2003-01-01

The Huang-Hilbert transform is a promising new method for analyzing nonstationary and nonlinear datasets. In this talk I will apply this technique to several important geophysical datasets. To understand the strengths and weaknesses of this method, multi- year, hourly datasets of the sea level heights and solar radiation will be analyzed. Then we will apply this transform to the analysis of gravity waves observed in a mesoscale observational net.

Canopy reflectance related to marsh dieback onset and progression in Coastal Louisiana

USGS Publications Warehouse

Ramsey, Elijah W.; Rangoonwala, A.

2006-01-01

In this study, we extended previous work linking leaf spectral changes, dieback onset, and progression of Spartina alterniflora marshes to changes in site-specific canopy reflectance spectra. First, we obtained canopy reflectance spectra (approximately 20 m ground resolution) from the marsh sites occupied during the leaf spectral analyses and from additional sites exhibiting visual signs of dieback. Subsequently, the canopy spectra were analyzed at two spectral scales: the first scale corresponded to whole-spectra sensors, such as the NASA Earth Observing-1 (EO-1) Hyperion, and the second scale corresponded to broadband spectral sensors, such as the EO-1 Advanced Land Imager and the Landsat Enhanced Thematic Mapper. In the whole-spectra analysis, spectral indicators were generated from the whole canopy spectra (about 400 nm to 1,000 nm) by extracting typical dead and healthy marsh spectra, and subsequently using them to determine the percent composition of all canopy reflectance spectra. Percent compositions were then used to classify canopy spectra at each field site into groups exhibiting similar levels of dieback progression ranging from relatively healthy to completely dead. In the broadband reflectance analysis, blue, green, red, red-edge, and near infrared (NIR) spectral bands and NIR/green and NIR/red transforms were extracted from the canopy spectra. Spectral band and band transform indicators of marsh dieback and progression were generated by relating them to marsh status indicators derived from classifications of the 35 mm slides collected at the same time as the canopy reflectance recordings. The whole spectra and broadband spectral indicators were both able to distinguish (a) healthy marsh, (b) live marsh impacted by dieback, and (c) dead marsh, and they both provided some discrimination of dieback progression. Whole-spectra resolution sensors like the EO-1 Hyperion, however, offered an enhanced ability to categorize dieback progression. ?? 2006 American Society for Photogrammetry and Remote Sensing.

Water mass transformation along the Indonesian throughflow in an OGCM

NASA Astrophysics Data System (ADS)

Koch-Larrouy, Ariane; Madec, Gurvan; Blanke, Bruno; Molcard, Robert

2008-11-01

The oceanic pathways connecting the Pacific Ocean to the Indian Ocean are described using a quantitative Lagrangian method applied to Eulerian fields from an ocean general circulation model simulation of the Indonesian seas. The main routes diagnosed are in good agreement with those inferred from observations. The secondary routes and the Pacific recirculation are also quantified. The model reproduces the observed salt penetration of subtropical waters from the South Pacific, the homohaline stratification in the southern Indonesian basins, and the cold fresh tongue which exits into the Indian Ocean. These particular water mass characteristics, close to those observed, are obtained when a tidal mixing parameterization is introduced into the model. Trajectories are obtained which link the water masses at the entrance and at the exit of the Indonesian throughflow (ITF), and the mixing along each trajectory is quantified. Both the ITF and the Pacific recirculation are transformed, suggesting that the Indonesian transformation affects both the Indian and Pacific stratification. A recipe to form Indonesian water masses is proposed. We present three major features of the circulation that revisit the classical picture of the ITF and its associated water mass transformation, while still being in agreement with observations. Firstly, the homohaline layer is not a result of pure isopycnal mixing of the North Pacific Intermediate Water and South Pacific Subtropical Water (SPSW) within the Banda Sea, as previously thought. Instead, the observed homohaline layer is reproduced by the model, but it is caused by both isopycnal mixing with the SPSW and a dominant vertical mixing before the Banda Sea with the NPSW. This new mechanism could be real since the model reproduces the SPSW penetration as observed. Secondly, the model explains why the Banda Sea thermocline water is so fresh compared to the SPSW. Until now, the only explanation was a recirculation of the freshwater from the western route. The model does not reproduce this recirculation but instead shows strong mixing of the SPSW within the Halmahera and Seram Seas, which erodes the salinity maximum so that its signature is not longer perceptible. Finally, this work highlights the key role of the Java Sea freshwater. Even though its annual net mass contribution is small, its fresh salinity contribution is highly significant and represents the main reason why the Pacific salinity maxima are eroded.

Immediate impact of the 'Exxon Valdez' oil spill on marine birds

USGS Publications Warehouse

Piatt, John F.; Lensink, Calvin J.; Butler, William; Kendziorek, Marshal

1990-01-01

On 24 March 1989, the oil tanker 'Exxon Valdez' spilled 260,000 barrels of crude oil in Prince William Sound, Alaska. Oil eventually drifted over $30,000\\ {\\rm km}^{2}$ of coastal and offshore waters occupied by approximately one million marine birds. More than 30,000 dead birds of 90 species were retrieved from polluted areas by 1 August 1989. Of those identified, murres (74%), other alcids (7.0%), and sea ducks (5.3%) suffered the highest mortality from oil, and most (88%) birds were killed outside of Prince William Sound. A colony of 129,000 murres at the Barren Islands was probably devastated. Another 7,000 birds were retrieved between 1 August and 13 October, but most of those birds appeared to have died from natural causes. This later die-off was composed largely of shearwaters and other procellariids (51%), gulls (22%), and puffins (14%). Based on aerial and ship-based surveys for populations at risk, and extrapolating from the number of dead birds recovered, we estimate that the total kill from oil pollution was from 100,000 to 300,000 birds.

Origin of marginal basins of the NW Pacific and their plate tectonic reconstructions

NASA Astrophysics Data System (ADS)

Xu, Junyuan; Ben-Avraham, Zvi; Kelty, Tom; Yu, Ho-Shing

2014-03-01

Geometry of basins can indicate their tectonic origin whether they are small or large. The basins of Bohai Gulf, South China Sea, East China Sea, Japan Sea, Andaman Sea, Okhotsk Sea and Bering Sea have typical geometry of dextral pull-apart. The Java, Makassar, Celebes and Sulu Seas basins together with grabens in Borneo also comprise a local dextral, transform-margin type basin system similar to the central and southern parts of the Shanxi Basin in geometry. The overall configuration of the Philippine Sea resembles a typical sinistral transpressional "pop-up" structure. These marginal basins except the Philippine Sea basin generally have similar (or compatible) rift history in the Cenozoic, but there do be some differences in the rifting history between major basins or their sub-basins due to local differences in tectonic settings. Rifting kinematics of each of these marginal basins can be explained by dextral pull-apart or transtension. These marginal basins except the Philippine Sea basin constitute a gigantic linked, dextral pull-apart basin system.

Fatal Attraction of Short-Tailed Shearwaters to Artificial Lights

PubMed Central

Rodríguez, Airam; Burgan, Graeme; Dann, Peter; Jessop, Roz; Negro, Juan J.; Chiaradia, Andre

2014-01-01

Light pollution is increasing around the world and altering natural nightscapes with potential ecological and evolutionary consequences. A severe ecological perturbation caused by artificial lights is mass mortalities of organisms, including seabird fledglings that are attracted to lights at night on their first flights to the sea. Here, we report on the number of fledging short-tailed shearwaters Ardenna tenuirostris found grounded in evening and morning rescue patrols conducted at Phillip Island, Australia, during a 15-year period (1999–2013). We assessed factors affecting numbers of grounded birds and mortality including date, moon phase, wind direction and speed, number of visitors and holiday periods. We also tested experimentally if birds were attracted to lights by turning the lights off on a section of the road. Of 8871 fledglings found, 39% were dead or dying. This mortality rate was 4–8 times higher than reported elsewhere for other shearwater species, probably because searching for fledglings was part of our systematic rescue effort rather than the opportunistic rescue used elsewhere. Thus, it suggests that light-induced mortality of seabirds is usually underestimated. We rescued more birds (dead and alive) in peak fledging, moonless and windy nights. Mortality increased through the fledging period, in the mornings and with increased traffic on holiday periods. Turning the road lights off decreased the number of grounded birds (dead and alive). While moon, wind and time are uncontrolled natural constraints, we demonstrated that reduction of light pollution and better traffic management can mitigate artificial light-induced mortality. PMID:25334014

Carbon dynamics in a Late Quaternary-age coastal limestone aquifer system undergoing saltwater intrusion.

PubMed

Bryan, Eliza; Meredith, Karina T; Baker, Andy; Andersen, Martin S; Post, Vincent E A

2017-12-31

This study investigates the inorganic and organic aspects of the carbon cycle in groundwaters throughout the freshwater lens and transition zone of a carbonate island aquifer and identifies the transformation of carbon throughout the system. We determined 14 C and 13 C carbon isotope values for both DIC and DOC in groundwaters, and investigated the composition of DOC throughout the aquifer. In combination with hydrochemical and 3 H measurements, the chemical evolution of groundwaters was then traced from the unsaturated zone to the deeper saline zone. The data revealed three distinct water types: Fresh (F), Transition zone 1 (T1) and Transition zone 2 (T2) groundwaters. The 3 H values in F and T1 samples indicate that these groundwaters are mostly modern. 14 C DOC values are higher than 14 C DIC values and are well correlated with 3 H values. F and T1 groundwater geochemistry is dominated by carbonate mineral recrystallisation reactions that add dead carbon to the groundwater. T2 groundwaters are deeper, saline and characterised by an absence of 3 H, lower 14 C DOC values and a different DOC composition, namely a higher proportion of Humic Substances relative to total DOC. The T2 groundwaters are suggested to result from either the slow circulation of water within the seawater wedge, or from old remnant seawater caused by past sea level highstands. While further investigations are required to identify the origin of the T2 groundwaters, this study has identified their occurrence and shown that they did not evolve along the same pathway as fresh groundwaters. This study has also shown that a combined approach using 14 C and 13 C carbon isotope values for both DIC and DOC and the composition of DOC, as well as hydrochemical and 3 H measurements, can provide invaluable information regarding the transformation of carbon in a groundwater system and the evolution of fresh groundwater recharge. Copyright © 2017 Elsevier B.V. All rights reserved.

How to build a model illustrating sea-floor spreading and subduction

USGS Publications Warehouse

Lahr, J.C.

1999-01-01

This report describes how to build a model of the outer 300 km (180 miles) of the Earth that can be used to develop a better understanding of the principal features of plate tectonics, including sea-floor spreading, the pattern of magnetic stripes frozen into the sea floor, transform faulting, thrust faulting, subduction, and volcanism. In addition to a paper copy of this report, the materials required are a cardboard shoebox, glue, scissors, straight edge, and safety razor blade.

Aeronautic Instruments. Section VI : Aerial Navigation and Navigating Instruments

NASA Technical Reports Server (NTRS)

Eaton, H N

1923-01-01

This report outlines briefly the methods of aerial navigation which have been developed during the past few years, with a description of the different instruments used. Dead reckoning, the most universal method of aerial navigation, is first discussed. Then follows an outline of the principles of navigation by astronomical observation; a discussion of the practical use of natural horizons, such as sea, land, and cloud, in making extant observations; the use of artificial horizons, including the bubble, pendulum, and gyroscopic types. A description is given of the recent development of the radio direction finder and its application to navigation.

Hagai Ron (1944-2012)

NASA Astrophysics Data System (ADS)

Tauxe, Lisa

2012-11-01

Hagai Ron was born on a small kibbutz in Palestine, north of the Dead Sea. He passed away in the presence of his family on 10 September 2012. He is survived by three daughters and four grandchildren. After completing his Ph.D. at the Hebrew University of Jerusalem in 1984, he was a postdoctoral scholar at Stanford University, specializing in paleomagnetism and structural geology. He returned to Israel in 1987, building the first paleomagnetic laboratory in Israel at the Geophysical Institute of Israel. In 2001, he moved with his lab to the Hebrew University of Jerusalem, where he stayed until his retirement earlier this year.

Balneotherapy for osteoarthritis.

PubMed

Verhagen, A P; Bierma-Zeinstra, S M A; Boers, M; Cardoso, J R; Lambeck, J; de Bie, R A; de Vet, H C W

2007-10-17

Balneotherapy (or spa therapy, mineral baths) for patients with arthritis is one of the oldest forms of therapy. One of the aims of balneotherapy is to soothe the pain and as a consequence to relieve patients' suffering and make them feel well. In this update we included one extra study. To assess the effectiveness of balneotherapy for patients with osteoarthritis (OA). We searched the following databases up to October 2006: EMBASE, PubMed, the Cochrane 'Rehabilitation and Related Therapies' Field database, PEDro, CENTRAL (Issue 3, 2006) and performed reference checking and communicated with authors to retrieve eligible studies. Randomised controlled trials (RCT) comparing balneotherapy with any intervention or no intervention. At least 90% of the patient population had to be diagnosed with OA. Two authors independently assessed quality and extracted data. Disagreements were solved by consensus. In the event of clinical heterogeneity or lack of data we refrained from statistical pooling. Seven trials (498 patients) were included in this review. Two studies compared spa-treatment with no treatment. One study evaluated baths as an add-on treatment to home exercises and another compared thermal water from Cserkeszölö with tap water (placebo). Three studies evaluated sulphur or Dead Sea baths with no treatment or mineral baths with tap water baths or no treatment. Only one of the trials performed an intention-to-treat analysis and two studies provided data to perform an intention-to-treat analysis ourselves. A 'quality of life' outcome was reported by one trial. We found: silver level evidence concerning the beneficial effects on pain, quality of life and analgesic intake of mineral baths compared to no treatment (SMD between 1.82 and 0.34). a statistically significant difference in pain and function of Dead Sea + sulphur versus no treatment, only at end of treatment (WMD 5.7, 95%CI 3.3 to 8.1), but not at 3 month follow-up (WMD 2.6, 95%CI -1.1 to 6.3). no statistically significant differences in pain or function at one or three months of Dead Sea baths versus no treatment (WMD 0.5, 95%CI -0.6 to 1.6) or at one or three months of sulphur baths versus no treatment (WMD 0.4, 95%CI -0.9 to 1.7). Adverse events were not measured in the included trials. We found silver level evidence (www.cochranemsk.org) concerning the beneficial effects of mineral baths compared to no treatment. Of all other balneological treatments no clear effects were found. However, the scientific evidence is weak because of the poor methodological quality and the absence of an adequate statistical analysis and data presentation. Therefore, the noted "positive findings" should be viewed with caution.

Controls on the pH of hyper-saline lakes - A lesson from the Dead Sea

NASA Astrophysics Data System (ADS)

Golan, Rotem; Gavrieli, Ittai; Ganor, Jiwchar; Lazar, Boaz

2016-01-01

The pH of aqueous environments is determined by the dominant buffer systems of the water, defined operationally as total alkalinity (TA). The major buffer systems in the modern ocean are carbonic and boric acids of which the species bicarbonate, carbonate and borate make up about 77%, 19% and 4% of the TA, respectively. During the course of seawater evaporation (e.g. lagoons) the residual brine loses considerable portion of the dissolved inorganic carbon (DIC) and carbonate alkalinity (CA) already at the early stages of evaporation. DIC and CA decrease due to massive precipitation of CaCO3, while total boron (TB) increases conservatively, turning borate to the dominant alkalinity species in marine derived brines. In the present work we assess the apparent dissociation constant value of boric acid (KB‧) in saline and hypersaline waters, using the Dead Sea (DS) as a case study. We explain the DS low pH (∼6.3) and the effect of the boric and carbonic acid pK‧-s on the behavior of the brine's buffer system, including the pH increase that results from brine dilution. The KB‧ in DS was estimated from TB, TA, DIC and pH data measured in this study and early empirical data on artificial DS brines containing just carbonic acid. The KB‧ value was corroborated by Pitzer ion interaction model calculations using PHREEQC thermodynamic code applied to the chemical composition of the DS. Our results show that KB‧ increases considerably with the brine's ionic strength, reaching in the DS to a factor of 100 higher than in ;mean; seawater. Based on theoretical calculations and analyses of other natural brines it is suggested that brines' composition is a major factor in determining the KB‧ value and in turn the pH of such brines. We show that the higher the proportion of divalent cations in the brine the higher the dissociation constants of the weak acids (presumably due to formation of complexes). The low pH of the Dead Sea is accordingly explained by its extremely high ionic strength (TDS = 348 g/L) and the dominance of the divalent cation, Mg2+. Other natural hyper-saline brines with high concentration of divalent cations such as Kunteyi Lake in China and Don-Juan Pond in Antarctica follow the same general pattern. In contrast, the high pH of soda lakes results not only from their high TA but also by the dominance of the monovalent cation, Na+. Our study emphasizes the strong control of brine composition on pKB‧ and pH. These factors should be taken into consideration when reconstructing past and present environmental evaporitic environments.

High-resolution InSAR constraints on flood-related subsidence and evaporite dissolution along the Dead Sea shores: Interplay between hydrology and rheology

NASA Astrophysics Data System (ADS)

Shviro, Maayan; Haviv, Itai; Baer, Gidon

2017-09-01

Sinkhole generation and land subsidence are commonly attributed to dissolution of subsurface layers by under-saturated groundwater and formation of cavities. Along the Dead Sea (DS) shorelines, this process also involves seasonal flash floods that are drained into the subsurface by existing and newly formed sinkholes. We quantify the contribution of flash-floods to salt dissolution and land subsidence using high-resolution interferometric synthetic aperture radar (InSAR). Subsidence rates during a 3-year period (2012-2015) were calculated from 57 COSMO SkyMed X-band interferograms bracketing major flood events and intra-flood periods in 21 sinkhole sites. The sites are located within channels and alluvial fans along the western shores of the Dead Sea, Israel. The observed subsidence reaches maximum rates of 2.5 mm/day, accumulating in specific sites to 500 mm/year. In most of the sinkhole sites a gradual increase in the annual subsidence rate is observed during the 3-year study period. Three different modes of response to floods were observed: (1) sites where floodwater is not directly channeled into sinkholes do not respond to floods; (2) sites adjacent to active channels with sinkholes are unaffected by specific floods but their subsidence rates increase gradually from early winter to mid-summer, and decay gradually until the following winter; and (3) sites in active channels with sinkholes are characterized by an abrupt increase in subsidence rates immediately after each flood (by a factor of up to 20) and by a subsequent quasi-exponential subsidence decay over periods of several months. In these latter sites, subsidence rates after each flood are temporally correlated with alternating groundwater levels in adjacent boreholes. The rapid rise in groundwater head following floods increases the hydraulic gradient of the under-saturated groundwater and hence also the groundwater discharge and the dissolution rate of the subsurface salt layer. A subsequent quasi-exponential water level drop results in similar deceleration in dissolution and subsidence rates, with a similar characteristic decay time of about 150 days. The observed subsidence decay pattern may also be explained by viscoelastic relaxation of the overburden in response to instantaneously-formed dissolution cavities. Utilizing a Kelvin viscoelastic model, we show that the contribution of this process is most probably < 30% of the total observed subsidence and is sensitive to the sediment mechanical properties. On a broader scale, this study demonstrates how high-resolution InSAR measurements can improve our understanding of subsurface dissolution and subsidence processes and provide independent constraints on the mechanical properties of heterogeneous alluvial sediments.

Lagrangian study of transport of subarctic water across the Subpolar Front in the Japan Sea

NASA Astrophysics Data System (ADS)

Prants, Sergey V.; Uleysky, Michael Yu.; Budyansky, Maxim V.

2018-06-01

The southward near-surface transport of transformed subarctic water across the Subpolar Front in the Japan Sea is simulated and analyzed based on altimeter data from January 1, 1993 to December 31, 2017. Computing Lagrangian indicators for a large number of synthetic particles, advected by the AVISO velocity field, we find preferred transport pathways across the Subpolar Front. The southward transport occurs mainly in the central part of the frontal zone due to suitable dispositions of mesoscale eddies promoting propagation of subarctic water to the south. It is documented with the help of Lagrangian origin and L-maps and verified by the tracks of available drifters. The transport of transformed subarctic water to the south is compared with the transport of transformed subtropical water to the north simulated by Prants et al. (Nonlinear Process Geophys 24(1):89-99, 2017c).

Lagrangian study of transport of subarctic water across the Subpolar Front in the Japan Sea

NASA Astrophysics Data System (ADS)

Prants, Sergey V.; Uleysky, Michael Yu.; Budyansky, Maxim V.

2018-05-01

The southward near-surface transport of transformed subarctic water across the Subpolar Front in the Japan Sea is simulated and analyzed based on altimeter data from January 1, 1993 to December 31, 2017. Computing Lagrangian indicators for a large number of synthetic particles, advected by the AVISO velocity field, we find preferred transport pathways across the Subpolar Front. The southward transport occurs mainly in the central part of the frontal zone due to suitable dispositions of mesoscale eddies promoting propagation of subarctic water to the south. It is documented with the help of Lagrangian origin and L-maps and verified by the tracks of available drifters. The transport of transformed subarctic water to the south is compared with the transport of transformed subtropical water to the north simulated by Prants et al. (Nonlinear Process Geophys 24(1):89-99, 2017c).

Plant genetic transformation efficiency of selected Malaysian rice based on selectable marker gene (hptII).

PubMed

Htwe, Nwe Nwe; Ling, Ho Chai; Zaman, Faridah Qamaruz; Maziah, Mahmood

2014-04-01

Rice is one of the most important cereal crops with great potential for biotechnology progress. In transformation method, antibiotic resistance genes are routinely used as powerful markers for selecting transformed cells from surrounding non-transformed cells. In this study, the toxicity level of hygromycin was optimized for two selected mutant rice lines, MR219 line 4 and line 9. The mature embryos were isolated and cultured on an MS medium with different hygromycin concentrations (0, 20, 40, 60, 80 and 100 mg L(-1)). Evidently, above 60 mg L(-1) was effective for callus formation and observed completely dead. Further there were tested for specific concentration (0-60). Although, 21.28% calli survived on the medium containing 45 mg L(-1) hygromycin, it seemed suitable for the identification of putative transformants. These findings indicated that a system for rice transformation in a relatively high frequency and the transgenes are stably expressed in the transgenic plants. Green shoots were regenerated from the explant under hygromycin stress. RT-PCR using hptII and gus sequence specific primer and Southern blot analysis were used to confirm the presence of the transgene and to determine the transformation efficiency for their stable integration in regenerated plants. This study demonstrated that the hygromycin resistance can be used as an effective marker for rice transformation.

Recent Changes in Land Water Storage and its Contribution to Sea Level Variations

NASA Astrophysics Data System (ADS)

Wada, Yoshihide; Reager, John T.; Chao, Benjamin F.; Wang, Jida; Lo, Min-Hui; Song, Chunqiao; Li, Yuwen; Gardner, Alex S.

2017-01-01

Sea level rise is generally attributed to increased ocean heat content and increased rates glacier and ice melt. However, human transformations of Earth's surface have impacted water exchange between land, atmosphere, and ocean, ultimately affecting global sea level variations. Impoundment of water in reservoirs and artificial lakes has reduced the outflow of water to the sea, while river runoff has increased due to groundwater mining, wetland and endorheic lake storage losses, and deforestation. In addition, climate-driven changes in land water stores can have a large impact on global sea level variations over decadal timescales. Here, we review each component of negative and positive land water contribution separately in order to highlight and understand recent changes in land water contribution to sea level variations.

Recent Changes in Land Water Storage and Its Contribution to Sea Level Variations

NASA Technical Reports Server (NTRS)

Wada, Yoshihide; Reager, John T.; Chao, Benjamin F.; Wang, Jida; Lo, Min-Hui; Song, Chunqiao; Li, Yuwen; Gardner, Alex S.

2016-01-01

Sea level rise is generally attributed to increased ocean heat content and increased rates glacier and ice melt. However, human transformations of Earth's surface have impacted water exchange between land, atmosphere, and ocean, ultimately affecting global sea level variations. Impoundment of water in reservoirs and artificial lakes has reduced the outflow of water to the sea, while river runoff has increased due to groundwater mining, wetland and endorheic lake storage losses, and deforestation. In addition, climate-driven changes in land water stores can have a large impact on global sea level variations over decadal timescales. Here, we review each component of negative and positive land water contribution separately in order to highlight and understand recent changes in land water contribution to sea level variations.

Transformational Capacity - Exploring a Places Ability to Change

NASA Astrophysics Data System (ADS)

Hirschfeld, D.

2016-12-01

In the face of climate change, there is an emerging consensus that local transformations are necessary in order to avoid the most catastrophic of losses (Burch et al. 2014; Preston et al. 2013). Specifically, it is well known that rising sea levels will lead to increased flooding and habitat loss (McGranahan, et al., 2007). Solutions to sea level rise and its associated impacts will require the active participation of coastal communities who will continue to be relied upon for most of the critical land use and planning decisions (Hurlimann and March 2012). While local governments are needed, these changes are known to be extremely difficult and require a shift to a new development path. Additionally, municipalities need to be able to identify places that can be altered to prepare for sea level rise. Thus we need to enhancer our understanding of transformational capacity. The range of future sea level rise projections are well understood, what is not known is how people will react and change the coastal landscape to address these threats. Additionally, it is not well understood how these different shorezone strategies will in turn impact people. Building on other long-term historical models in coastal engineering, we have developed a framework to generate potential future shorezones in a complex estuarine environment. As shown in Figure 1, the framework includes three general components to determine potential future shorezones. Within each general part of the framework, there are a number of critical data sets used to support this part of the model. For example, the economic piece of the analysis includes, the costs of coastal protective infrastructure and the values of upland parcels. The future shorezones generated through this analysis will be used in sea level rise impacts assessments allowing for a richer conversation in the climate adaptation process. Ultimately, the goals of this presentation are to 1) introduce this specific framework designed to assess the transformational capacity of places 2) use the framework to compare and assess components of the system and 3) show results from research in the San Francisco Bay.

Sarcocystis neurona retinochoroiditis in a sea otter (Enhydra lutris kenyoni).

PubMed

Dubey, J P; Thomas, N J

2011-12-29

Sarcocystis neurona is an important cause of fatal disease in sea otters in the USA. Encephalitis is the predominant lesion and parasites are confined to the central nervous system and muscles. Here we report retinochoroiditis in a sea otter (Enhydra lutris kenyoni) found dead on Copalis Beach, WA, USA. Salient lesions were confined to the brain and eye. Multifocal nonsuppurative meningoencephalitis was present in the cerebrum and cerebellum associated with S. neurona schizonts. The retina of one eye had a focus of inflammation that contained numerous S. neurona schizonts and merozoites. The focus extended from the retinal pigment epithelium inward through all layers of the retina, but inflammation was most concentrated at the inner surface of the tapetum and the outer retina. The inner and outer nuclear layers of the retina were disorganized and irregular at the site of inflammation. There was severe congestion and mild hemorrhage in the choroid, and mild hemorrhage into the vitreous body. Immunohistochemistry with S. neurona-specific polyclonal rabbit antibodies stained schizonts and merozoites. To our knowledge this is the first report of S. neurona-associated retinochoroiditis in any naturally infected animal. Copyright © 2011 Elsevier B.V. All rights reserved.