scholarly journals Sharp changes in lake-levels preconditioning seismogenic mass failures in the Dead Sea

Author(s):  
Yin Lu ◽  
Amotz Agnon ◽  
Shmuel Marco ◽  
Revital Bookman ◽  
Nicolas Waldmann ◽  
...  

<p>Subaqueous mass failures that comprise slides, slumps and debris flows are a major process that transport sediments from the continental shelf and upper slope to the deep basins (both oceans and lacustrine settings). They are often viewed together with other natural hazards such as earthquakes, and can have serious socioeconomic consequences. It is increasingly important to understand the relationship between mass failures and climate-driven factors such as changes in water-level. Despite extensive marine investigations on this topic world-wide, the relationship between changes in water-level and mass failures is still highly disputed. This is due largely to the significant uncertainties in age dating and different potential triggers and preconditioning factors of mass failure events from different geological settings. Here, we present a 70 kyr-long record of mass failure from the Dead Sea Basin center (ICDP Core 5017-1). This sedimentary sequence has been dated in high accuracy (±0.6 kyr) and has similar responses to climate forcing. Moreover, the mass failure record is interpreted to be controlled by a single trigger mechanism (i.e. seismicity).<br>Based on the recent detailed study on the sedimentological signature of seismic shaking in the Dead Sea center, these seismogenic mass failures (seismites) account only for a part of the whole seismites catalog, suggesting that mass failure follows only part of seismic shaking irrespective of intensities of the shaking. This is evidenced by the common absence of mass failures following the in situ developed and preserved seismites (e.g., the in situ folded layer and intraclast breccias layer) which represent different intensities of seismic shaking. This feature implies that some non-seismic factor(s) must have preconditioned for the seismogenic mass failures in the Dead Sea center.<br>Our observations reveal decoupling between change in sedimentation rates and occurrence probability of these seismogenic mass failures, thus suggesting that a change in sedimentation rate is not the preconditioning factor for the failure events. While 79% of seismogenic mass failure events occurred during lake-level rise/drop in contrast to 21% events occurred in the quiescent intervals between. Our dataset implies that seismogenic mass failures can occur at any lake-level state, but are more likely to occur during lake-level rise/drop due to the instability of the basin margins. In addition, the seismogenic mass failures occurred more frequently during glacials (characterized by highstand and high-amplitude lake-level changes) than during interglacials, as a result of the morphologic characteristics of the lake margin slopes and different lithologies (e.g. halite) influences which are both connected to the glacial-interglacial lake-level changes.</p>

2020 ◽  
Author(s):  
Julius Jara-Muñoz ◽  
Amotz Agnon ◽  
Jens Fohlmeister ◽  
Jürgen Mey ◽  
Norbert Frank ◽  
...  

<p><span>High-resolution records of lake-level changes are crucial to elucidate the impact of local and global climatic changes in lacustrine basins. The Late Quaternary evolution of the Dead Sea has been characterized by substantial variability apparently linked with global climatic changes, beign subject of many research efforts since decades. Previous studies have defined two main lake phases, the Lake Lisan and the Dead Sea, the earlier was a highstand period that lasted between ~70 and ~15 ka, the  latter was the lowstand period that persisted until the present. Here we focus on the switch between Lake Lisan and Dead Sea studying fossil lake shorelines, a sequence that comprises dozens of levels exposed along the rims of the Dead Sea, containing abundant fossil stromatolites that we dated by mean of radiocarbon and U-decay series. We determined 90 radiocarbon and 35 U-Th ages from stromatolites from almost every shoreline level. We compared U-Th and radiocarbon ages to estimating a radiocarbon reservoir between 0.2 and 0.8 ka, used to correct the remaining radiocarbon ages before calibration. The resulting ages range between ~45  and ~20 ka. Dating was </span><span>complemented with analysis of stable oxygen and carbon isotopes. Furthermore, we applied a distributed hydrological balance model to constrain past precipitation and temperature conditions. Our results suggest that the duration of the last Lake Lisan highstand was shorter than previously estimated. Taking this at face value, the switch between Lake Lisan and Dead Sea occurred at ~28 ka, ~10 ka earlier than previously suggested. Oxygen and carbon isotopes show a consistent pattern, displaying a switch between wet and dry conditions at ~28 ka. Preliminary results from the hydrological model indicate a much stronger sensitivity of the lake level to precipitation amounts than to air temperature. From our results we can’t observe a clear link between global temperature variations and lake-level changes in the Lisan/Dead Sea lakes. Similar non-linear response to northern hemisphere climatic changes have been also documented in Holocene Dead Sea paleoclimatic records, suggesting that global climatic variations may led to variable lake-level responses. The results of this study adds further complexity to the understanding of factors controlling climate variability in the Dead Sea. </span></p>


2017 ◽  
Vol 464 ◽  
pp. 211-226 ◽  
Author(s):  
Yael Kiro ◽  
Steven L. Goldstein ◽  
Javier Garcia-Veigas ◽  
Elan Levy ◽  
Yochanan Kushnir ◽  
...  

2002 ◽  
Vol 57 (1) ◽  
pp. 9-21 ◽  
Author(s):  
Yuval Bartov ◽  
Mordechai Stein ◽  
Yehouda Enzel ◽  
Amotz Agnon ◽  
Ze'ev Reches

AbstractLake Lisan, the late Pleistocene precursor of the Dead Sea, existed from ∼70,000 to 15,000 yr B.P. It evolved through frequent water-level fluctuations, which reflected the regional hydrological and climatic conditions. We determined the water level of the lake for the time interval ∼55,000–15,000 cal yr B.P. by mapping offshore, nearshore, and fan-delta sediments; by application of sequence stratigraphy methods; and by dating with radiocarbon and U-series methods. During the studied time interval the lake-level fluctuated between ∼340 and 160 m below mean sea level (msl). Between 55,000 and 30,000 cal yr B.P. the lake evolved through short-term fluctuations around 280–290 m below msl, punctuated (at 48,000–43,000 cal yr B.P.) by a drop event to at least 340 m below msl. At ∼27,000 cal yr B.P. the lake began to rise sharply, reaching its maximum elevation of about 164 m below msl between 26,000 and 23,000 cal yr B.P., then it began dropping and reached 300 m below msl at ∼15,000 cal yr B.P. During the Holocene the lake, corresponding to the present Dead Sea, stabilized at ca. 400 m below msl with minor fluctuations. The hypsometric curve of the basin indicates that large changes in lake area are expected at above 403 and 385 m below msl. At these elevations the lake level is buffered. Lake Lisan was always higher than 380 m below msl, indicating a significantly large water contribution to the basin. The long and repetitious periods of stabilization at 280–290 m below msl during Lake Lisan time indicate hydrological control combined with the existence of a physical sill at this elevation. Crossing this sill could not have been achieved without a dramatic increase in the total water input to the lake, as occurred during the fast and intense lake rise from ∼280 to 160 m below msl at ∼27,000 cal yr B.P.


2006 ◽  
Vol 66 (3) ◽  
pp. 421-431 ◽  
Author(s):  
Claudia Migowski ◽  
Mordechai Stein ◽  
Sushma Prasad ◽  
Jörg F.W. Negendank ◽  
Amotz Agnon

AbstractA comprehensive record of lake level changes in the Dead Sea has been reconstructed using multiple, well dated sediment cores recovered from the Dead Sea shore. Interpreting the lake level changes as monitors of precipitation in the Dead Sea drainage area and the regional eastern Mediterranean palaeoclimate, we document the presence of two major wet phases (∼ 10–8.6 and ∼ 5.6–3.5 cal kyr BP) and multiple abrupt arid events during the Holocene. The arid events in the Holocene Dead Sea appear to coincide with major breaks in the Near East cultural evolution (at ∼ 8.6, 8.2, 4.2, 3.5 cal kyr BP). Wetter periods are marked by the enlargement of smaller settlements and growth of farming communities in desert regions, suggesting a parallelism between climate and Near East cultural development.


2013 ◽  
Vol 40 (2) ◽  
pp. 115-143 ◽  
Author(s):  
David N. Herda ◽  
Stephen A. Reed ◽  
William F. Bowlin

This study explores the Dead Sea Scrolls to demonstrate how Essene socio-religious values shaped their accounting and economic practices during the late Second Temple period (ca. first century BCE to 70 CE). Our primary focus is on the accounting and commercial responsibilities of a leader within their community – the Examiner. We contend that certain sectarian accounting practices may be understood as ritual/religious ceremony and address the performative roles of the Essenes' accounting and business procedures in light of their purity laws and eschatological beliefs. Far from being antithetical to religious beliefs, we find that accounting actually enabled the better practice and monitoring of religious behavior. We add to the literature on the interaction of religion with the structures and practices of accounting and regulation within a society.


2021 ◽  
Vol 19 (1) ◽  
pp. 15-26
Author(s):  
Cecilia Wassén

Abstract In this article, I engage with Joel Marcus’s recent book on John the Baptist, focusing on the relationship between John and the Dead Sea Scrolls. While I appreciate many parts of his detailed study, I question the claim that John was a former member of the Essenes. Although there are intriguing similarities, the question is how far reaching conclusions we may draw concerning such a relationship. I problematize some aspects of the comparison between the sources. Like many scholars, Marcus refers in particular to 1QS and the site of Khirbet Qumran for reconstructing the Essenes and hence John’s background. In response, I highlight the uncertainty about the Sitz im leben of 1QS in relation to Khirbet Qumran and ask why this particular manuscript should be privileged over others. Not least when it comes to purity halakhah there are many other documents than 1QS from Qumran that are highly relevant to the issue. Finally, I critically evaluate Marcus’s view that John the Baptist had a favorable attitude towards Gentiles, which according Marcus differed from the views of the Essenes.


2021 ◽  
Author(s):  
Musab Mbideen ◽  
Balázs Székely

<p>Remote Sensing (RS) and Geographic Information System (GIS) instruments have spread rapidly in recent years to manage natural resources and monitor environmental changes. Remote sensing has a vast range of applications; one of them is lakes monitoring. The Dead Sea (DS) is subjected to very strong evaporation processes, leading to a remarkable shrinkage of its water level. The DS is being dried out due to a negative balance in its hydrological cycle during the last five decades. This research aims to study the spatial changes in the DS throughout the previous 48 years. Change detection technique has been performed to detect this change over the research period (1972-2020). 73 Landsat imageries have been used from four digital sensors; Landsat 1-5 MSS C1 Level-1, Landsat 4-5 TM C1 Level-1, Land sat 7 ETM+ C1  Level-1, and Landsat 8 OLI-TIRS C1 Level. After following certain selection criteria , the number of studied images decreased. Furthermore, the Digital Surface Model of the Space Shuttle Radar Topography Mission and a bathymetric map of the Dead Sea were used. The collected satellite imageries were pre-processed and normalized using ENVI 5.3 software by converting the Digital Number (DN) to spectral radiance, the spectral radiance was converted to apparent reflectance, atmospheric effects were removed, and finally, the black gaps were removed. It was important to distinguish between the DS lake and the surrounding area in order to have accurate results, this was done by performing classification techniques. The digital terrain model of the DS was used in ArcGIS (3D) to reconstruct the elevation of the shore lines. This model generated equations to detect the water level, surface area, and water volume of the DS. The results were compared to the bathymetric data as well. The research shows that the DS water level declined 65 m (1.35 m/a) in the studied period. The surface area and the water volume declined by 363.56 km<sup>2 </sup>(7.57 km<sup>2</sup>/a) and 53.56 km<sup>3</sup> (1.11 km<sup>3</sup>/a), respectively. The research also concluded that due to the bathymetry of the DS, the direction of this shrinkage is from the south to the north. We hypothesize that anthropogenic effects have contributed in the shrinkage of the DS more than the climate. The use of the DS water by both Israel and Jordan for industrial purposes is the main factor impacting the DS, another factor is the diversion of the Jordan and Yarmouk rivers. Our results also allow to give a prediction for the near future of the DS: the water level is expected to reach –445 m in 2050, while the surface area and the water volume is expected to be 455 km<sup>2</sup> and 142 km<sup>3</sup>, respectively. </p>


2022 ◽  
pp. 1118-1129
Author(s):  
Nawaf N. Hamadneh

In this study, the performance of adaptive multilayer perceptron neural network (MLPNN) for predicting the Dead Sea water level is discussed. Firefly Algorithm (FFA), as an optimization algorithm is used for training the neural networks. To propose the MLPNN-FFA model, Dead Sea water levels over the period 1810–2005 are applied to train MLPNN. Statistical tests evaluate the accuracy of the hybrid MLPNN-FFA model. The predicted values of the proposed model were compared with the results obtained by another method. The results reveal that the artificial neural network (ANN) models exhibit high accuracy and reliability for the prediction of the Dead Sea water levels. The results also reveal that the Dead Sea water level would be around -450 until 2050.


2011 ◽  
Vol 75 (3) ◽  
pp. 430-437 ◽  
Author(s):  
Liisa Nevalainen ◽  
Kaarina Sarmaja-Korjonen ◽  
Tomi P. Luoto

AbstractThe usability of subfossil Cladocera assemblages in reconstructing long-term changes in lake level was examined by testing the relationship between Cladocera-based planktonic/littoral (P/L) ratio and water-level inference model in a surface-sediment dataset and in a 2000-yr sediment record in Finland. The relationships between measured and inferred water levels and P/L ratios were significant in the dataset, implying that littoral taxa are primarily deposited in shallow littoral areas, while planktonic cladocerans accumulate abundantly mainly in deepwater locations. The 2000-yr water-level reconstructions based on the water-level inference model and P/L ratio corresponded closely with each other and with a previously available midge-inferred water-level reconstruction from the same core, showing a period of lower water level around AD 300–1000 and suggesting that the methods are valid for paleolimnological and -climatological use.


2019 ◽  
Author(s):  
Samiro Khodayar ◽  
Johannes Hoerner

Abstract. The Dead Sea desertification-threatened region is affected by continual lake level decline and occasional, but life-endangering flash-floods. Climate change has aggravated such issues in the past decades. In this study, the impact of the Dead Sea drying on the severe convection generating heavy precipitation in the region is investigated. Perturbation simulations with the high-resolution convection-permitting regional climate model COSMO-CLM and several numerical weather prediction (NWP) runs on an event time scale are performed over the Dead Sea area. A reference simulation covering the 2003 to 2013 period and a twin sensitivity experiment, in which the Dead Sea is dried out and set to bare soil, are compared. NWP simulations focus on heavy precipitation events exhibiting relevant differences between the reference and the sensitivity decadal realization to assess the impact on the underlying convection-related processes. On a decadal scale, the difference between the simulations points out that in future regional climate, under ongoing lake level decline, a decrease in evaporation, higher air temperatures and less precipitation is to expect. Particularly, an increase in the number of dry days and in the intensity of heavy precipitation is foreseen. The drying of the Dead Sea is seen to affect the atmospheric conditions leading to convection in two ways: (a) the local decrease in evaporation reduces moisture availability in the lower boundary layer locally and in the neighbouring, directly affecting atmospheric stability. Weaker updrafts characterize the drier and more stable atmosphere of the simulations where the Dead Sea has been dried out. (b) Thermally driven wind system circulations and resulting divergence/convergence fields are altered preventing in many occasions convection initiation because of the omission of convergence lines.


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