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Routine quarrying activity at the Nesher-Ramla Quarry, in the Judean Lowlands, Israel, has recently exposed a new Early Holocene archaeological site located in a small natural sinkhole, one of many dolines scattered in the area, dated to the Early Pre-Pottery Neolithic B (EPPNB). It is the first site of this period to be uncovered in the narrow strip of land between the Judean Mts. and the coastal plain. This site, dubbed NRQN, contains lithic artifacts, groundstone tools, shells and beads as well as botanical and faunal remains. Here we combine data from a series of studies on the site's stratigraphy and radiometric dating, paleoenvironment, sediments and material culture, with the aim of understanding the role of the site in the EPPNB sphere. Various human activities took place in or immediately adjacent to the sinkhole, predominantly domestic in nature, including stone-tool making and food consumption. However, some of the sediments deep within the sinkhole underwent intense in situ combustion, possibly associated with episodes of lime-plaster production. The filling of the sinkhole appears to have occurred rapidly, not exceeding a few hundred years (ca. 10,500–10,300 cal. BP) and was driven by both geogenic and anthropogenic sedimentation processes. Good preservation of microvertebrate, macrovertebrae, short-lived plants and wood remains at the site, provides a unique opportunity to study the environmental characteristics of this geographical area during the Early Holocene, which appears to have been of an open grassy landscape with patchy Mediterranean forest, resembling the current environmental conditions. Studying the characteristics of Early Holocene human activity at the site, its paleoenvironment, and the site formation mechanisms, also provides useful comparisons with the nearby NRQ Middle Paleolithic site (this issue).

The Ayyalon - Nesher Ramla (ANR) system combines hypogenic karst with endemic subterranean fauna. The unique faunal assemblage utilizes chemosynthetic food web based upon H2S within the ascending plumes of hydrothermal water. We attempt to constrain the regional biogeography and the age of the hypogene system using subterranean extant ‘living fossils’, combined with related taxa in the Dead Sea Rift and Mediterranean, as well as geological evidence and previously published molecular phylogenetic data. The molecular evidence of Typhlocaris ayyaloni and T. salentina suggested that ANR aquatic system age is > 5.8 Ma. Evidence from Dead Sea Rift and East Mediterranean biogeographic evolution of aquatic fauna indicates isolation of the rift water bodies from the Mediterranean ~7 Ma. The high endemism of terrestrial troglobites at Ayyalon - Nesher Ramla caves indicate longer isolation age, most probably ~14 Ma – the end of the last transgression which inundated the lower Shefela region. We show that the Ayyalon terrestrial fauna of tropical origin invaded the subsurface warm, humid, and food-rich habitat, escaping middle Miocene surface aridization. Shefela sinkholes preserving middle Miocene sediments share similar features with Nesher Ramla sinkholes, suggesting that they share the same formation processes ~14 Ma, and implying a minimum age of the sulfidic hypogenic aquifer.

2 páginas.- 1 figura.- 16 referencias, To the Editor — 2021 is the International Year of Caves and Karst. To honour this occasion, we wish to emphasize the vast potential embodied in planetary subsurfaces. While researchers have pondered the possibility of extraterrestrial caves for more than 50 years, we have now entered the incipient phase of planetary caves exploration....

The Levant region of Israel, located along the Eastern Mediterranean Sea, is characterized by Mediterranean climate, but sixty km eastwards towards the Dead Sea Rift Valley (DSRV), the region rapidly becomes a ‘rain shadowʼ desert. Speleothems from the Mediterranean climate zone continuously grew throughout several glacial/interglacial cycles, indicating that water was always available in the unsaturated zone. Their δ18O variations match global and regional climate changes, with the Eastern Mediterranean Sea being the major control on their δ18O values, as evident from the similarity between the speleothems and the planktonic foraminifer G. ruber records. In contrast, speleothems along the central and southern segments of the DSRV grew mainly during last glacial periods coinciding with the higher stands of Lake Lisan, the precursor of the present-day Dead Sea. This paper discusses the newly discovered Zalmon Cave speleothems, located in the northern segment of the DSRV shedding light on the hydrological conditions along the rift during last glacial. Unlike speleothems located further south along the DSRV, Zalmon Cave speleothems grew both during glacial and interglacial periods. However, during last glacial their δ18O values, shifted to lower values by ∼1–2‰ relative to speleothems from central Israel coinciding also with the largest difference in δ18O values between Zalmon Cave speleothems and the marine record. The data suggest that a change of the westerlies' storm tracks occurred during most of the last glacial period, which resulted in increased rainfall in the northern DSRV providing freshwater input during the otherwise relatively ‘drierʼ glacial.

Research on planetary caves requires cross-planetary-body investigations spanning multiple disciplines, including geology, climatology, astrobiology, robotics, human exploration and operations. The community determined that a roadmap was needed to establish a common framework for planetary cave research. This white paper is our initial conception

The southern Levant region at the fringe of the Saharan-Arabian deserts is particularly vulnerable to warming and desertification, therefore reconstruction of the hydroclimate conditions of this region during periods of past climate change provide important insight on what may occur in the future. Here we report on high temporal resolution 87Sr/86Sr, δ13C and δ18O isotope data of a stalagmite from the Har Nof cave in Jerusalem, demonstrating major climate changes during the last interglacial MIS5e between ~131–116 ka. We combine also data from other caves in Israel and the ICDP Dead Sea deep drill core. The following palaeoenvironmental history is observed: • At 131–127.5 ka, Jerusalem experienced moderate Mediterranean climate conditions. Desert dust accumulated above the cave, while salt deposition occurred in the Dead Sea. • At 127.5–122 ka, across the MIS5e insolation peak and Sapropel S5 interval in the Mediterranean, highly negative speleothem δ18O indicate both Mediterranean and southern (tropical) derived rains. Surface cover diminished, and by 122 ka the 87Sr/86Sr and δ13C values indicate complete soil removal above the cave. Very high temperatures and intensive fires caused the removal of C3 vegetation. The rainfall season shifted from winter to summer with tropical-sourced precipitation. • At 122–120.5 ka, the 87Sr/86Sr ratios indicate contributions of sea salts. Extremely high speleothem δ13C values indicate no vegetation. • At ~120.5–118 ka there was higher rainfall and lower temperatures, associated with re-establishment of vegetation, including savannah-like C4 pioneer grasses that appeared on soil patches. • At 118–116 ka, the sedimentation rate of Har Nof AF12 stalagmite is extremely low, indicating regional aridity, coinciding with massive salt deposition in the Dead Sea.

Recent environmental processes are studied in ʻA’rak Naʻasane Cave at the northern Judean Desert, Israel. The outer zone of the cave is heavily influenced by the outside environment through a large entrance, facilitating entry of air flow, fauna and humans, with minor cave-forming modifications. Conversely, the inner cave sustains humid and warm conditions, favoring modifications by condensation corrosion of convective air flow, associated with deposition of popcorn speleothems at the lower parts of dissolution pockets. The warm humid air of the inner cave may be associated with an underlying thermal water table. Active condensation corrosion is decreasing, possibly because of gradual change in the cave microclimate, associated with falling water table and ventilation. Increasing connection with the surface is indicated by high collapse domes, rare flood invasion, and a large Trident Leaf-nosed bat community which spends the winter within the innermost parts of the cave. Bat guano supports bedrock corrosion and a rich invertebrate fauna, but humans preferred the outer parts of the cave, particularly for refuge during the second Jewish revolt against the Romans. Rare occasions of ancient human entry into the inner cave support this scenario by the small number of artifacts compared with the outer cave. Enigmatic small cairns in the largest inner hall were probably erected during the Intermediate Bronze Age.

Banded terrain is a planetary enigma that may be associated with salt diapirs. We study such features in Mount Sedom diapir, which is one of the few places on Earth where rock-salt is partly exposed and well-preserved because of the extreme aridity of its setting. The relief and surface features of the diapir generally reflect its parent-rock geological structure, stratigraphy and lithology on one hand, and recent erosion and dissolution on the other hand. We show that these features are commonly aligned along parallel strike-oriented lines forming banded terrain. We measure the surface deformation, demonstrating an absolute uplift rate reaching ~7–8 mm/yr. The extruded volume rate of Mt. Sedom bedrock is estimated to be 48,000 ± 12,000 m3/yr. Subtracting erosion and dissolution, the ridge mass increases by 70,000 ± 20,000 metric tons per year, inducing a young (Holocene) and steep landscape. We compare surface landforms with subsurface geology exposed in caves. They include lines of sliding faults, dissolution furrows, sinkholes of dissolution and collapse origin, karstic shafts, and an irregular disrupted drainage system dominated by blind valleys. The diapir rock-salt is covered by residual caprock, in its turn partly overlain by less consolidated hardly-soluble sediments and gravels. Terraces of abrasion and regressing lakeshore of the Dead Sea appear along the ridge margins. Exposed salt outcrops are relatively rare and undergo rapid dissolution, demonstrated by karst features which range from ponors to the longest salt caves known globally. The extreme solubility of the underlying salt influences the surface and subsurface landscape, inducing high permeability along fractures, and promoting runoff capture into the underlying salt. All studied landforms contribute to the banded relief of Mount Sedom, which can be used to analyze banded or closely-related honeycomb terrain across other terrestrial and planetary diapirs.

A karst survey of the western upper Galilee in Israel shows that karst has been a dominant geomorphic factor throughout the Cenozoic. We discuss the geomorphic character of Manot Cave on the background of other karst features of the region, in order to decipher the preferences of the humans who favored this cave over others. Tens of caves distributed over the study area demonstrate that phreatic and hypogene isolated voids and conduit segments are more abundant than vadose shafts, sinking stream caves and spring caves, although all these types are present. Most caves belong to old stages of landform development, prior to Plio-Pleistocene uplift and stream entrenchment. Manot Cave is a relict chamber cave, which corresponds to a plaeo-water table and the erosion plain above it. Subaerial denudation and slope processes have opened the cave to the surface during the mid-late Pleistocene. Manot Cave is compared with other caves in the region, demonstrating its unique character. It may have been selected due to the small entrance facing to the SW, and the large inner chamber which could be used for non-domestic purposes. This suggests a possible role of a unique behavioral and cultural suite of characters which influenced hominin preferences. The cave was used by hominins and animals until being closed again by colluvium and possibly collapse, ∼30 ka. Clastic, chemical, archaeozoological and anthropogenic accumulations reflect the various stages of cave development and gradual sealing of the entrance.

Evaporite karst is intensively developing at the Dead Sea (DS), both along its western and eastern shores. The collapse of overlying sediments into evaporite karst cavities results in sinkhole formation. The dissolution is produced by undersaturated water, aggressive concerning halite. The evaporite karst is developing rapidly, in the time scale of months to years, so groundwater aggressiveness is a relevant factor for sinkhole susceptibility assessment. The present study analyzes sinkhole development concerning groundwater aggressiveness. The aggressiveness is evaluated from bulk resistivity (ρx) of the aquifer, measured from the surface using the Transient Electromagnetic (TEM) method, and from resistivity (ρw) of groundwater filling its pores. We suggest a methodology for water aggressiveness determination and its classification concerning salt. We then demonstrate a significant correlation between water aggressiveness and the actual distribution of sinkholes in five study areas along the Dead Sea. Conversely, we show that the timing of sinkholes occurrence within recent decades does not correlate with water aggressiveness. The timing is attributed to the multiple factors that control the dissolution of salt and consequent collapse. Acknowledging that the real hydrogeological conditions involve multifactorial processes, we shortly analyze other concurrent factors, including water table depth, existing salt karstification east of the salt edge, and site location relative to the salt edge.

A last interglacial (Marine Isotope Stage, MIS5e) marine-coastal sequence has been identified along the Galilee coast of Israel, with the type section located at Rosh Hanikra (RH). The microtidal regime and tectonic stability, along with the detailed stratigraphy of the RH shore, make the study region ideally suited for determining relative sea level (RSL) through the MIS5e interval in the eastern Mediterranean. The sequence contains fossilized microtidal subunits at a few meters above the current sea level. Unfortunately, all fossils were found to be altered, so that U-Th datings cannot be considered to represent initial deposition. We contend that U-Th dating of Strombus bubonius shells (recrystallized to calcite) suffices to indicate a lower limit of ?110 ± 8 ka for the time sea level dropped below the RH sedimentary sequence. The RH-section comprises three main subunits of a previously determined member (the Yasaf Member): (a) a gravelly unit containing the diagnostic gastropod Strombus bubonius Lamarck (Persististrombus latus), which was deposited in the intertidal to super-tidal stormy zone; (b) Vermetidae reef domes indicating a shallow-water depositional environment; and (c) coarse to medium-sized, bioclastic sandstone, probably deposited in the shallow sub-tidal zone. The sequence overlies three abrasion platforms that are cut by tidal channels at elevations of +0.8 m, +2.6 m and +3.4 m, and which are filled with MIS5e sediments. We present a detailed study of the sequence, with emphasis on stratigraphic, sedimentological, and palaeontological characteristics that indicate sea-level changes. Although without precise absolute dating, the stratigraphic sequence of RH through MIS5e allows us to identify a time-series of RSL positions, using the elevations of three stratigraphic subunits. Reconstructed RSL values range from +1.0 m to +7 m (with uncertainly < 1 m), and most fall within a narrow range of +1.0 to +3.3 m. Toward the end of MIS5e, RSL exceeded about +7 m. Glacial isostatic adjustment (GIA) modelling using multiple ice histories suggests that GIA corrections range between about ?1.8 m and +5.4 m. This implies that global mean sea level resided between ?0.8 m and +8.7 m during most of MIS5e. The absolute GIA correction would not be constant through the interglacial, and reduces to a range of ?1.2 m to+ 2.4 m towards the end of the interglacial.

South-western Samaria is emerging as a major province of Paleolithic cave sites. Most recently discovered caves have been naturally filled with terra-rossa type colluvial deposits when the hillslopes above the caves were stripped from vegetation during late Quaternary times. Site formation processes differ significantly between caves with pit-like openings, such as Qesem, Emanuel, and Rantis caves, vs. those with cliff-side entrances, such as Shukbah, Tinshemet, and Deir Kaddis caves. The former favored accumulation of colluvial debris, while the latter were relatively protected from these deposits. Caves discovered in the 20th century were mainly of the latter, cliff-face type, while in the 21st century new discoveries commonly occur where construction works intersect previously unnoticed filled caves.

Middle Paleolithic human occupation in the Levant (250–50 ka ago) has been recorded in roofed (cave and rockshelter) and open-air sites. Research at these different types of sites yielded different perspectives on the Middle Paleolithic human behavior and evolution. Until recently, open-air Middle Paleolithic sites in the Levant were found in three major sedimentary environments: fluvial, lake-margin and spring. Here we describe a unique depositional environment and formation processes at the recently discovered open-air site of Nesher Ramla (Israel) and discuss their contribution to understanding site formation processes in open-air sites in the Levant. The site is 8-m-thick Middle Paleolithic sequence (OSL dated to 170–80 ka) that is located in a karst sinkhole formed by gravitational deformation and sagging into underground voids. The sedimentary sequence was shaped by gravitational collapse, cyclic colluviation of soil and gravel into the depression, waterlogging, in situ pedogenesis and human occupation. Original bedding and combustion features are well-preserved in the Lower archaeological sequence, a rare occurrence in comparison to other open-air archaeological sites. This phenomenon coincides with episodes of fast sedimentation/burial, which also allowed better preservation of microscopic remains such as ash. The Upper archaeological sequence does not exhibit bedding or preservation of ash, despite presence of heat-affected lithic artifacts, which makes it similar to other open-air sites in the Levant. We suggest that rate of burial is the major factor that caused the difference between the Upper and Lower sequences. The differences in the burial rate may be connected to environmental and vegetation changes at the end of MIS 6. We also identified an interplay between sediment in-wash and density of human activity remains, i.e. during episodes of low natural sediment input the density of artifacts is higher relative to episodes with high rate of sediment in-wash. The detailed analysis of natural and anthropogenic processes at Nesher Ramla suggests a much wider spectrum of processes than previously reported for southern Levantine Paleolithic sites. Nesher Ramla shares certain depositional and post-depositional characteristics with both cave and open-air sites and provides a better insight into processes which control both types of sites.

The western and eastern Dead Sea (DS) shores are hit by intensive sinkhole collapse during the last 30 years. The first researchers have considered a piping model of sinkhole formation, based on washing out fines by underground flows. Then, it was proved by numerous boreholes and seismic refraction surveys that sinkholes along western shore are caused by dissolution of buried salt layers and collapse of the surface into dissolution caverns. However, signs of piping and subsurface flows were observed in some sinkhole sites. In this paper, we show that robust identification of sinkhole origin can be achieved when proper geophysical methodologies and their application are used. We consider Newe Zohar site located in the southern part of the Dead Sea in order to analyse different signs of sinkhole formation models using various geophysical methods. The Seismic refraction method (SRFR), enables us to discover the salt layer based on longitudinal wave velocity Vp; the Multichannel Analysis of Surface Waves (MASW) method allows to determine the salt layer properties (rigidity) based on shear wave velocity Vs; finally, the Time Electromagnetic (TEM) method allows us to evaluate the degree of aggressiveness of groundwater with respect to salt, based on bulk resistivity values. Here we analyse competitive models of sinkhole formation and suggest geophysical methods to determine the subsurface geomorphology. We show that various geophysical methods should be applied in concert to explore the subsurface for the occurrence of salt, as well as understanding sinkhole formation processes. The underlying voids along the Dead Sea are shown to form primarily by salt dissolution, with some cases of additional piping. Applying the right geophysical parameters for groundwater and salt sediments classification proves to be crucial for understanding the subsurface geomorphology.

Despite numerous studies examining salt tectonics, relatively little is known regarding the internal movements of salt units that build diapirs such as the Mount Sedom salt wall. In this study we focus on the recent deformation processes of southern Mount Sedom. We choose a fossilized dissolution surface known as the “salt mirror” of Mount Sedom as a structural datum, in order to understand and resolve the deformation processes during the last 14 ka. Surveying the salt mirror surface from outcrops and natural dissolution “chimney” caves, sets constraints for the structural map. Our results indicate that the salt wall rises as a telescopic antenna, with the internal salt units sliding across each other along bedding-plane slip faults, influenced by the subsiding Dead Sea basin. The flow of the rising salt forms an elongated ridge, distinctly asymmetric across its short dimension. The uplift rate of the Southern part of Mount Sedom throughout the last 14 ka is at least 11 mm/yr. This result is somewhat higher but in a fair agreement with the results of previous studies that assessed the rates in a variety of methods. The telescopic behavior of the salt wall represents a mode of internal deformation that might be applicable to other salt diapirs worldwide.

We show that clusters of karst sinkholes can occur on carbonate hypogene karst terrains. Unlike common doline karst of dissolution origin, the studied sinkholes form mainly by sagging and collapse. Thermal survey, OSL dating and morphologic analysis during quarrying and excavations are applied to study the sinkholes at the Ayyalon karst, Israel. The thermal survey shows the spatial pattern of rising warm water plumes, whose temperature is > 2 °C warmer than the surrounding aquifer water. These plumes dissolve the limestone, creating large voids and maze caves. Mass wasting forms surface sinkholes mainly by sagging and collapse. Both types of deformation often occur within the same depression. Lack of hydrologic connection between the surface and underground voids constrain drainage and promote rapid accumulation of colluvium, dust and pedogenic clays. These have filled the sinkholes up to their rim before the late Holocene. OSL dating constrains the rate of sediment accumulation within the sinkholes. The average filling rate (thickness divided by elapsed time) is ~ 47 mm ka − 1 for the last 53 ± 4 ka in Sinkhole 1, while in Sinkhole 2 (“Nesher Ramla karst depression”), the rate is ~ 61 mm ka − 1 from ~ 200 to 78 ka, and ~ 173 mm ka − 1 since ~ 78 ka. Between ~ 170 and 78 ka, Sinkhole 2 was intensively used by Middle Paleolithic hominins. The studied sinkholes may be considered as a type locality for hypogene sinkhole terrain on carbonate rocks.

Inland notches are defined herein as horizontal “C”-shaped indentations, developed on the carbonate slopes or cliffs in the Mediterranean to semi-arid zones. The notches are shaped like half tubes that extend over tens or hundreds of meters along the stream valley slopes. In Mt. Carmel, a series of 127 notches have been mapped. On average, their height and width are 2–2.5 m but they can reach 6 m in height and 9.5 m in width. The geomorphic processes that create a notch combine chemical, mechanical, and biogenic weathering, which act together to generate initial dissolution and later flake weathering (exfoliation) of the bed, forming the notch cavity. We propose an epikarstic-subaerial mechanism for the formation and evolution of the notches. The notches are unique landforms originating from the dissolution and disintegration of the rock under subaerial conditions, by differential weathering of beds with different petrographic properties. The notches follow specific beds that enable their formation and are destroyed by the collapse of the upper bed. The formation and destruction alternate in cyclical episodes and therefore, the notches are local phenomena that vary over time and space.

The Judean Desert in eastern Israel consists of a Late Cretaceous epicontinental carbonate terrain formed at the interface between the Neotethys Ocean and the Gondwanian African-Arabian plate. Various rock types were deposited through fluctuations between marine and continental environments due to ingressions and regressions. Orogenic folding of the Syrian Arc fold system occurred between the Late Cretaceous and the Neogene. The folds formed a barrier for deep flowing groundwater, which upwelled along the SE flank of the folds. Possibly mixing with local confined circulation, the hypogene flow created maze caves at the top of the Late Cretaceous limestone, under the confinement of thick chalk, and marl successions. The larger caves are up to 3.5-km-long 2D mazes, less commonly with some additional tiers. Speleogenesis occurred most likely during the Oligocene, when far-field recharge could reach the Judean Desert. During the Neogene, the Dead Sea transform has dissected the region, forming a deep endorheic depression at the eastern border of the Judean Desert. This was followed by the lowering of the water table and related dewatering of the caves. Fault escarpments and downcutting canyons have dissected the caves, forming the present entrances. The caves are mostly dry, with rare speleothems. Gypsum rinds indicate that hydrogen sulfide and sulfuric acid took part in speleogenesis.

International audience; Kahf Kharrat Najem Cave is a small cave in United Arab Emirates (UAE) that hosts a bat colony which is the source of guano deposits and peculiar centimeter-long yellowish stalactites. The mineralogy and geochemistry of these deposits were analyzed using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopic microanalysis (EDX), scanning electron microscope (SEM), and stable isotope composition (δ 13 C and δ 15 N). Urea CO(NH 2) 2 was found to be the main compound of these stalactites, while allantoin C 4 H 6 N 4 O 3 was found to be an accessory urea byproduct. This paper is the first to mention allantoin in a cave environment. We also identified rare sulfate minerals (aphthitalite, alunite) and phosphates that probably correspond to the archerite-biphosphammite series. The occurrence of these rare bat-related minerals is due to the extremely dry conditions in the cave, which accounts for the extraordinary preservation of the guano deposits and allows for the crystallization of these very soluble minerals. cave minerals, allantoin, bat guano, bat urea, Kahf Kharrat Najem Cave, United Arab Emirates

A new approach for dating ancient quarries is applied to shed new light on the problem of calcite-alabaster provenance in the southern Levant. Until now, calcite-alabaster artifacts from this region were commonly attributed to Egyptian sources. This raw material was used for the production of luxury vessels as well as high-class architectural elements and furniture. We show for the first time that calcite-alabaster was quarried in the southern Levant from flowstone, which is deposited in karstic caves under free air conditions. Two flowstone quarries were discovered, in Te'omim and 'Abud Caves, located on the western slopes of the Central Highlands of Israel. Both quarries produced together over 200 m 3 of raw material. A broken column at 'Abud Cave indicates that large calcite-alabaster artifacts were produced inside the cave. Following the quarrying, additional flowstone was deposited on top of the quarried surface by continuous sheet flow of water. We use this deposit to constrain the quarrying period. The first abandoned parts of the Te'omim quarry are dated by U–Th to the Middle Bronze Age (first half of the 2nd millennium BCE). This dating is corroborated by archaeological finds within Te'omim Cave, as well as by the wide distribution of calcite-alabaster artifacts in south Levantine sites during this period.

We report the discovery of a new type of hominin site in the Levant, inhabited during MIS 6–5. The site, found within a karst depression at Nesher Ramla, Israel, provides novel evidence for Middle Paleolithic lifeways in an environmental and depositional setting that is previously undocumented in the southern Levant. The carbonate bedrock in the area is characterized by surface depressions formed by gravitational sagging of the rock into underlying karst voids. In one such depression, an 8 m thick sequence comprising rich and well-preserved lithic and faunal assemblages, combustion features, hundreds of manuports and ochre was discovered. Here we focus on the geological and environmental setting and present optically stimulated luminescence (OSL) ages for the 8 m sequence, aiming to place the site within a firm chronological framework and determine its significance for a more complete reconstruction of cultural developments in the Levantine Middle Paleolithic. To that end, preliminary results of the lithic and faunal studies are also presented.

There are two conflicting models of sinkhole development along the Dead Sea (DS). The first one considers structural control on sinkholes, constraining them to tectonic lineaments. This hypothesis is based on seismic reflection studies suggesting that sinkholes are the surface manifestations of active neotectonic faults that may serve as conduits for under-saturated groundwater, enabling its access across aquiclude layers. Another hypothesis, based on results of multidisciplinary geophysical studies, considers the salt edge dissolution front as the major site of sinkhole formation. This hypothesis associates sinkholes with karstification of the salt edge by deep and shallow undersaturated groundwater. Our recent seismic reflection and surface wave studies suggest that salt formed along the active neotectonic faults. Sinkholes form in a narrow strip (60–100 m wide) along a paleo-shoreline constrained by faults and alluvial fans which determined the edge of the salt layer. This scenario reconciles the two major competing frameworks for sinkhole formation.

This study focuses on warm Last Glacial episodes in the southernmost extension of the Alpine karst range of the Eastern Mediterranean (Levant) region through the study speleothems in Mizpe Shelagim Cave, located in Mt. Hermon. The Alpine karst range extends from Turkey through Syria and Lebanon, reaching its southern limit in Mt. Hermon at an elevation of more than 2000 m. Under present-day conditions, southern Mt. Hermon receives 1000–2000 mm precipitation, mostly as snow, that originates in the Eastern Mediterranean Sea. Speleothems deposition in this high altitude region was continuous during interglacials, but during the Last Glacial growth only occurred when average annual temperatures exceeded ∼3 °C as inferred from the study of speleothem fluid inclusions. Warming episodes occurred at: ∼65 ka, ∼56 ka, 54.5 ka, ∼52.5–51 ka, ∼49 ka, ∼42 ka, and ∼36 ka and are coincident with maximum insolation at 65 °N. The main depositional period from ∼56 ka to 51 ka coincides with Dansgaard–Oeschger interstadial 15 and 14, and warming in the northeastern basin of the Mediterranean Sea. Warming in the southern Alpine karst range of the Eastern Mediterranean was manifested by vegetation development, together with significant snow melting that resulted in the drainage of large amount of water to the Dead Sea Rift Valley.

This paper explores the environmental conditions that faced the people of ancient Jawa during the Holocene, as well as previous prehistoric periods of the mid-late Pleistocene. Calcite speleothems in a lava tube are dated using the U-Th method, to marine oxygen isotope stage 7 from ∼250 to 240 ka and from ∼230 to ∼220 ka; and the stage 5/4 transition between ∼80 and 70 ka. The available evidence indicates general aridity of the Black Desert during most of the mid-late Quaternary, punctuated by short wetter periods, when the Mediterranean cyclonic systems intensified and penetrated the north Arabian Desert. These Mediterranean systems had a longer and more intense effect on the desert fringe closer to the Mediterranean and only rarely penetrated the Black Desert of Jawa. The results do not exclude some increase of rainfall which did not change water availability dramatically during the warm Holocene. The ancient Jawa city appears to have depended on technological ability to build elaborate runoff-collection systems, which became the prime condition for success. © 2008 University of Washington. All rights reserved.

The Middle-Late Pliocene climate was 2-3°C warmer than today, but with similar levels of atmospheric CO2. This period reflects climate conditions expected in the near future, and is therefore an important target for current data-modeling studies. This study reconstructs the Pliocene-Quaternary evolution of arid conditions on the northern margin of the Saharan-Arabian desert, using radiometrically (U-Pb) dated periods of speleothem deposition from three caves of the Negev Desert, Israel. Speleothem growth started between ~3.75 and ~3Ma, at the end of the first significant tectonic uplift of the western shoulder of the Dead Sea Rift. Major speleothem deposition, indicating wet conditions, occurred during the Pliocene around ~3.1Ma, with subsequent aridity during the last 3Myr, punctuated by short wet episodes - the Pleistocene Negev Humid Periods (NHP). The oldest dated NHP occurred between ~1.7 and ~1.25Ma, and other short humid episodes continued intermittently later. Speleothem δ18O values (-6.9‰ to -11.2‰) show that the humid episodes were associated with periods of low global ice volume and warm temperatures. After correction for rainfall δ18O changes associated with ice volume and temperature effects, the observed relative constancy of speleothem δ18O values from Pliocene to Late Pleistocene indicates rainfall was from a common source, most probably the eastern Mediterranean Sea. The humid Pliocene conditions could be generated by more southerly position of the Mediterranean coast (allowing the access of Mediterranean precipitation to the Negev), as well as by warmer Atlantic Sea Surface Temperatures, that weakened the Azores High Pressure Cell. Maximum amounts of precipitation were 500-600mm/a during the Pliocene and >300mm/a during Pleistocene NHP. The Pliocene and the earliest Pleistocene NHP are associated with formation of lakes in the Negev. Low 87Sr/86Sr ratios of ~0.7078 in the Pliocene speleothems are indicative of low dust supply, low water residence time in the vadose zone and relatively high weathering rates of the cave host rock. Increase of 87Sr/86Sr ratios to 0.7082-0.7083 in the Pleistocene suggest an increased supply of desert dust, high water residence time in the vadose zone and reduced host rock weathering. © 2013 Elsevier B.V.

In a recent article in this journal, geologists Amihai Sneh, Ram Weinberger, and Eyal Shalev proposed a new model for the why, how, and when of the Iron Age II Siloam Tunnel in ancient Jerusalem. Here we focus on the how of their contribution. Offered without presentation of new data or discussion of recently published evidence, their model is a refinement of ideas introduced since the early 20th century, mostly by scholars who had little geological knowledge and/or who failed to observe the internal features of the tunnel. Their model suggests that the tunnel follows a natural winding route of interconnected karstic cavities along fissures and bedding planes by jumping from one into the other close to the water table. Although theoretically possible in other karstic terrains, such a model is not applicable to the Siloam Tunnel because it clashes with the geological and other field evidence manifested along the tunnel. Our field observations show no indications of a groundwater water table close to the tu...

A geophysical approach is presented for analyzing processes of subsurface salt dissolution and associated sinkhole hazard along the Dead Sea. The implemented methods include Seismic Refraction (SRFR), Transient Electromagnetic Method (TEM), Electric Resistivity Tomography (ERT), and Ground Penetration Radar (GPR). The combination of these methods allows the delineation of the salt layer boundaries, estimating its porosity distribution, finding cavities within the salt layer, and identifying deformations in the overlying sediments. This approach is shown to be useful for anticipating the occurrence of specific sinkholes, as demonstrated on both shores of the Dead Sea. These sinkholes are observed mainly along the edge of a salt layer deposited during the latest Pleistocene, when Lake Lisan receded to later become the Dead Sea. This salt layer is dissolved by aggressive water flowing from adjacent and underlying aquifers which drain to the Dead Sea. Sinkhole formation is accelerating today due to the rapid fall of the Dead Sea levels during the last 30 years, caused by anthropogenic use of its water.

summary Deep karst voids can be identified by a new method of geophysical interpretation of commonly used borehole logs in deeply confined carbonate aquifers. We show that deep, buried karst voids can be characterized by combining this geophysical interpretation together with geological and hydrological data, and with known speleological constraints. We demonstrate how this characterization can reveal past hydrological regimes and allow mapping of karst distribution on a basin-wide scale. A combined analysis of geophysical, geological, hydrological, and speleological data in the confined Yarkon–Taninim aquifer, Israel, led us to reconstruct past groundwater levels at different relief and sea levels, with the karst voids as a marker for long-term flow close to the water table. Paleo-canyons along the Mediterranean Sea shoreline strongly affected the region’s paleo-hydrology, by serving as major outlets of the aquifer during most of the Cenozoic. We conclude that intensive karstification was promoted by flow periods of longer duration and/or higher flux and flow velocities close to the aquifer’s past and present outlets. In addition, we suggest that karst voids found under shallow confinement were developed by renewed aggressivity due to hypogene water rising in cross-formational flow becoming mixed with fresh lateral water flow from the east.

Rantis Cave is a recently discovered filled cave in central Israel, displaying a rich faunal accumulation of micro- mammals, ungulates and carnivores. U-Th dating assigns the beginning of accumulation to ca. 140 ka. The accumulation is culturally assigned to the late half of the Middle Paleolithic (MP) period. Single-grain optically stimulated luminescence measurements attest to a complex sedimentological history. We present the cross-disciplinary results of taphonomic and geomorphological analyses, which point to the cave serving as a natural pitfall trap for the large fauna, with little human or carnivore activity. The fauna is dominated by Dama among the ungulates and by Microtus among the micromammals. These data in conjunction with ungulate tooth mesowear analysis suggest a xeric Mediterranean environment on the eastern margin of the southern Levantine foothills. The relative taxonomic abundance of ungulate taxa shows some differences from anthropogenic MP sites, possibly reflecting the prey choice patterns of MP hunters. Overall, the natural accumulation scenario for Rantis Cave provides a rare paleoenvironmental and paleoeconomic reference to the rich anthropogenic MP faunas of the Southern Levant, enabling the reconstruction of a rich and diverse environmental setting for this important human dispersal route. Copyright # 2011 John Wiley & Sons, Ltd.

This paper explores the impact of major glacial/interglacial paleohydrologic variations in the Middle-Paleolithic Levant on hominin migration and occupation. The climatic reconstruction is based primarily on the most straight-forward paleohydrologic records recently published. These terrestrial proxies convey direct paleoenvironmental signals of effective precipitation and aquifer recharge. The two main proxies are temporal changes of terminal lake levels in the Dead Sea basin and periods of deposition or non-deposition of speleothems. Other records, such as stable isotopes, if interpreted correctly, correspond well with these two direct proxies. All the records consistently indicate that the last two glacial periods in the central Levant were generally wet and cool, while the last two interglacials were dry and warm, so more water was available for the ecosystem and thus hominins during glacial periods than during interglacials. Some proxies indicate that the higher precipitation/evaporation ratio during glacial periods involved higher precipitation rather than only reduced evaporation. Beyond the general mean glacial/interglacial climate suggested here, variations occurred at all temporal scales throughout glacial or interglacial periods. In the Sahara-Negev arid barrier, moister conditions occurred during Marine Isotope Stage (MIS) 6a-5e, when Anatomically Modern Humans apparently migrated out of Africa. We suggest that this migration, as well as the later Neanderthal expansion from Southeast Europe or the Anatolian plateau into the Levant during early MIS 4, could be facilitated by the observed major climatic variations.

Understanding recharge mechanisms and controls in karst regions is extremely important for managing water resources because of the dynamic nature of the system. The objective of this study was to evaluate water percolation through epikarst by monitoring water flow into a cave and conducting artificial irrigation and tracer experiments, at Sif Cave in Wadi Sussi, Israel from 2005 through 2007. The research is based on continuous high-resolution direct measurements of both rainfall and water percolation in the cave chamber collected by three large PVC sheets which integrate drips from three different areas (17, 46, and 52 m2). Barrels equipped with pressure transducers record drip rate and volume for each of the three areas. The combined measured rainfall and cave data enables estimation of recharge into the epikarst and to better understand the relationship of rainfall-recharge. Three distinct types of flow regimes were identified: (1) ‘Quick flow’ through preferential flow paths (large fractures and conduits); (2) ‘Intermediate flow’ through a secondary crack system; and (3) ‘Slow flow’ through the matrix. A threshold of ∼100 mm of rain at the beginning of the rainy season is required to increase soil water content allowing later rainfall events to percolate deeper through the soil and to initiate dripping in the cave. During winter, as the soil water content rises, the lag time between a rain event and cave drip response decreases. Annual recharge (140–160 mm in different areas in the cave) measured represents 30–35% of annual rainfall (460 mm). Copyright © 2011 John Wiley & Sons, Ltd.

We present here the results of a U–Th dating project at Qesem Cave, a Middle Pleistocene, late Lower Paleolithic site in Israel. It provides 54 new MC-ICP-MS U–Th ages for speleothems from the cave. The results indicate that human occupation started sometime between ∼420 and 320 ka and ended between 220 and 194 ka. A survey of dates from culturally similar sites in the Levant indicates that the general range of ca. 400–ca. 200 ka is an appropriate estimate for the life span of the Acheulo-Yabrudian Cultural Complex (AYCC).

Speleothems in arid and hyper-arid areas of Negev Desert, Israel, are used in paleoclimate reconstruction of northern margins of Saharan-Arabian Desert, focused on the following objectives: 1) precise U–Th dating of the timing of speleothem growth as an indicator of periods of humid climate, i.e. positive effective precipitation; 2) the origin of rainfall using the speleothem δ18O and changes in spatial pattern of speleothem deposition and speleothem thickness along a north–south transect; 3) changes of vegetation cover based on speleothem δ13C variations. During the last 350 ka major humid periods, referred to herein as Negev Humid Periods (NHP), occurred in the central and southern Negev Desert at 350–310 ka (NHP-4), 310–290 ka (NHP-3), 220–190 ka (NHP-2), and 142–109 ka (NHP-1). NHP-4, NHP-2 and NHP-1 are interglacial events, whereas NHP-3 is associated with a glacial period. During NHP-1, 2 and 3 the thickness and volume of the speleothems decrease from the north to the south, and in the most southern part of the region only a very thin flowstone layer formed during NHP-1, with no speleothem deposition occurring during NHP-2 and 3. These data imply that the Eastern Mediterranean Sea was the major source of the rainfall in northern and central Negev. More negative speleothem δ18O values, relative to central parts of Israel (Soreq Cave) are attributed to Rayleigh distillation because of the increasing distance from the Mediterranean Sea. Speleothem deposition during the NHP-4 in the southern Negev was more intensive than in most of the central Negev, suggesting the prominence of the tropical rain source. Decrease in speleothem δ13C during NHP events indicates growth of the vegetation cover. Nevertheless, the ranges of δ13C values show that the vegetation remained semi-desert C4 type throughout the NHPs, with an additional significant carbon fraction coming from the host rock and the atmosphere. These observations, together with small thickness of the speleothem layers, favor that NHP events consisted of clusters of very short humid episodes interspersed with long droughts. NHP events were contemporaneous with climate periods with monsoon index of ≥51 (cal/cm2 × day) and with the formation of sapropel layers in the Mediterranean Sea. Such simultaneous intensification of the monsoon and Atlantic-Mediterranean cyclones is probably related to the weakening of the high pressure cell above sub-tropical Atlantic Ocean, which enabled more rainfall to penetrate into the Saharan-Arabian Desert from the north and south. The contemporaneous occurrence of the NHP events and the increased monsoon rainfall could have opened migration corridors, creating climatic “windows of opportunity” for dispersals of hominids and animals out of the African continent.

Evaporitic-lagoonal marl and dolomite laminar fill sediments are preserved in relict dry caves of the Dead Sea Fault Escarpment (Israel) which has been tectonically active since the Late Neogene. The hosting caves are located within Turonian massive carbonate bedrock and at higher altitudes than previously documented fill sediments of the Dead Sea depression. Based on the relative altitudes of the cave sediments, the ‘reversed stratigraphy’ of the Dead Sea depression fill sediments, possible partial correlation of the cave sediments with other fill sedimentary units of the depression, and sedimentary, geochemical and mineralogical characteristics, it is concluded that: (i) the cave sediments are among the oldest of the depression fill; and (ii) the deposition of the cave sediments took place in hypersaline dolomite-precipitating water bodies of Late Neogene age, during the initial morphotectonic stages of the depression formation. Variable and relatively low Sr/Ca and δ34S ratios of the cave sediments (assuming precipitation from sea water) suggest variable fresh water input into the depositional brine. The present altitudes of the cave sediments reflect Late Neogene levels of water bodies in the depression, modified by vertical post-Late Neogene tectonic movements within the still active fault escarpment. According to these altitudes, a 50 to 250 m uplift of the western margins of the depression since the Late Miocene to Early Pliocene is inferred.

Trees growing on the Mt. Sedom salt diapir, at the southern Dead Sea shore, were swept by runoff into salt caves and subsequently deposited therein, sheltered from surface weathering. A subfossilTamarixtree trunk, found in a remote section of Sedom Cave is radiocarbon dated to between ∼ 2265 and 1930 BCE. It was sampled in 109 points across the tree rings for carbon and nitrogen isotopes. The SedomTamarixdemonstrates a few hundred years of13C and15N isotopic enrichment, culminating in extremely high δ13C and δ15N values. Calibration using modernTamarixstable isotopes in various climatic settings in Israel shows direct relationship between isotopic enrichment and climate deterioration, particularly rainfall decrease. The subfossilTamarixprobably reflects an environmental crisis during the Intermediate Bronze Age, which subsequently killed the tree ∼ 1930 BCE. This period coincides with the largest historic fall of the Dead Sea level, as well as the demise of the large regional urban center of the 3rd millennium BCE. The environmental crisis may thus explain the archaeological evidence of a shift from urban to pastoral culture during the Intermediate Bronze Age. This was apparently the most severe long-term historical drought that affected the region in the mid-late Holocene.

The Qesem karst system may serve as an example for aging chamber caves. It includes two caves which have undergone several stages of natural and human-induced deposition, as well as subsidence and collapse. Natural deposits include calcite speleothems, bedrock collapse debris, and clay fill. Karst dissolution and associated sagging and decomposition have operated since the initial cave formation. Inclined sediments are attributed to several processes, mostly dominated by gravitational sagging into underlying dissolution voids, affecting cave deposits and sometimes the host-rock. U-Th dating shows that speleothem deposition has been common during the mid-late Quaternary, but deposition sites shifted according to local conditions. The aging of caves occurs when they become totally filled by sediments and ultimately consumed by surface denudation, as documented in Qesem Cave. © 2008 Elsevier B.V. All rights reserved.

A varied assemblage of algal stromatolites was encountered in caves along the northern section of the Dead Sea Fault Escarpment. The caves are situated at the lower part of the escarpment at altitudes -310 to -188 m relative to mean sea level (m.s.l.), i.e. ca 110-230 m above the present Dead Sea level. The cave stromatolites are mainly composed of aragonite yielding U-Th ages of ∼75-17 ka. The altitude, mineralogy and ages, as well as comparison with previously documented stromatolite outcrops in the area, ascribe the cave stromatolites to the aragonite-precipitating hypersaline Lake Lisan-the Late Pleistocene predecessor of the Dead Sea. The stromatolites are used as a lake level gauge, based on the algae being reliant upon the light of the upper water layer. Preservation of the original structure and aragonite mineralogy of the stromatolites, suggests a closed system regarding the radioactive elements, enabling reliable U-Th dating. A curve of Lake Lisan levels is constructed based on the stromatolite ages and cave elevations. The following points are noted: (1) Lake levels of -247 m relative to m.s.l., are recorded at ∼75-72.5 ka; (2) relatively high lake levels above -220 m relative to m.s.l., are achieved at ∼41.5 ka, and are still recorded at ∼17 ka; (3) the peak level is -188 m relative to m.s.l., at ∼35.5-29.5 ka. These results indicate lake stands up to 80 m higher than previously accepted, for large parts of the Lake Lisan time span. This difference is explained by tectonic subsidence of up to 2.2 m/ka within the Dead Sea depression since the latest Pleistocene. This subsidence rate is in the same order of magnitude with previously calculated subsidence rates for the Dead Sea depression [Begin, Z.B., Zilberman, E., 1997. Main Stages and Rate of the Relief Development in Israel. Geological Survey of Israel report, Jerusalem]. Unlike previous Lake Lisan level estimations, the new curve is measured at the relatively stable shoulders of the Dead Sea depression. © 2008 Elsevier Ltd. All rights reserved.