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Detrital sediments of the Sea of Galilee are predominantly pedogenic products of settled dust and local bedrocks transported from Upper Galilee and the Golan Heights. Using the mineralogy, chemistry, and Nd and Sr isotope ratios of the core LK12-22 collected offshore of the Ginosar valley and of contemporaneous soils from the Nahal Tzalmon and Nahal Amud catchments, we reconstructed Late Holocene regional hydroclimate. The core samples span ɛNd isotope values of −6 to −2 and 87Sr/86Sr ratios of 0.7075 to 0.7077 between the isotope fields of the Terra rossa soils and basaltic soils. Sediments from the drier Iron Age and Arabic and Ottoman periods are closer in Nd-Sr isotope ratios of the basaltic soils, while those of the wetter Middle to Late Bronze and Roman–Byzantine periods are closer to the Terra rossa soils, reflecting enhanced mobilization of sediments from the Tzalmon catchment where Terra rossa–type soils accumulated. This result corroborates other regional data that indicate semiarid to temperate conditions in the south Levant during most of the Late Holocene. Wetter conditions over the Galilee Mountains and the Ginosar valley catchment during the Roman period could have promoted the flourishing farming-fishing society that heralded the rise of Christianity.

During the late Neogene, the east Mediterranean margins of the Levant went through major morphological changes due to tectonic activity associated with the Dead Sea Transform Fault. The regional fluvial systems inverted their flow direction from westward towards the Mediterranean to eastward towards the Jordan Valley. Tectonic basins that developed at that time in northern Israel were filled by lakes with intermittent connections to the sea. The tectonic processes were accompanied by volcanism of alkali basalts. This study focuses on the evolution of sedimentary-volcanic sequences, mainly included in the Bira and Gesher Formations that were deposited in lacustrine and palustrine environments in northern Israel. The study presents a comprehensive dataset and interpretation integrating new and old lithological and paleontological records from outcrops and drill holes, together with new petrographic and mineralogical data. The Bira Formation of Tortonian age, which overlies the Lower Basalt unit, consists mainly of lacustrine littoral limestone and dolostone and basinal marl. Sporadic occurrences of marine macrofauna indicate pulses of marine ingressions that reached the Jordan Valley depocenter, where thick sequences of gypsum and salt were deposited. The overlying Gesher Formation of Messinian-early Zanclean age, which has a similar lithology to that of the Bira Formation, represents an environmental evolution from restricted shallow lakes into a larger lake, or lakes, and finally to shallow isolated water bodies. The latter stage coincides with the Messinian Salinity Crisis, when climate became more arid in the Levant. Pyroclasts and some lava flows recorded an ongoing volcanic activity during this period that intensified toward the eruption of the Cover Basalt unit, that overlies the Gesher Formation. Overall, the Bira and Gesher formations provide a detailed sedimentological, tectonic and volcanic history of the continental margins of the east Mediterranean and its connection to the tectonic evolution of basin associated with the Dead Sea Transform Fault.

Initial soils covering archaeological ruins in the southern Levant include fine grain size fractions that may stem from aeolian sediments. Thus, ruins could act as effective dust traps which preserved rare Holocene aeolian records. We assessed physical parameters and chemical composition of initial soils covering archaeological ruins in the Negev and southern Jordan, including clay mineralogy and Sr- and Nd-isotopes, which we compared with modern dust from collectors installed close to the sites. A significant contribution from local weathered rocks could be observed in southern Jordan. In the Negev, the contribution of rocks was negligible, probably due to greater rock hardness and abundant biological crusts sealing surfaces. However, loessial paleosols surrounding the sampled archaeological ruins were "recycled" in the Negev. Compared to modern settled dust, archaeological soils in southern Jordan are enriched with various major and trace elements associated with clays and oxide coatings of fine silt particles. This was not due to in-situ weathering, which was found to be minimal. However, site-specific fixation processes may explain variations of dust records at the studied sites. In addition, modern dust samples associated with precipitation, in particular snow, were found associated with higher amounts of major and trace elements. Initial soils covering ruins in the southern Levant therefore suggest that the formation of soils in desert fringes may less be a function of dust supply, but more of dust deposition and fixation processes. There are multiple, local and regional dust sources and dust-generating processes active in drylands, but deep loessial soils form only when dust fixation is effective.

Ruins and archaeological structures in the southern Levant are often covered by initial soils that developed on debris. The fine grain size fractions of these soils may stem from aeolian sediments, and the ruins could serve as effective dust traps. The physical parameters and chemical composition of archaeological soils in hilltop ruins, cleanout spoils of cisterns, and ancient runoff-collecting terraces were determined in the Petra region in southern Jordan and the northern Negev in Israel. Different types of ruins could not be distinguished with regard to substrate composition. This indicates a predominance of aeolian processes for primary sedimentation, while fluvial processes only re-distribute aeolian material. In the Petra region, a significant local contribution from associated weathered rocks could be observed. Compared to modern settled dust, archaeological soils in southern Jordan are enriched with various major and trace elements associated with clays and oxide coatings of fine silt particles. In-situ weathering seems minimal, but preferential fixation of silt and clay by surface crusts (similar to desert pavements), and a role of moisture in sedimentation processes lead to increased sedimentation of calcareous silt. Contribution of rocks is negligible in the Negev due to greater rock hardness and abundant biological crusts sealing surfaces. Archaeological soils in the Negev and current settled dust consist of complex mixtures of local and remote sources, including significant portions of recycled material from paleosols. Archaeological soils in the southern Levant are archives of Holocene dust sources and aeolian sedimentation processes, with accretion rates exceeding those of Pleistocene hilltop loess in the Negev. Comparison with Pleistocene paleosols suggests that dust sources did not change significantly, but disappearance of snow could have reduced dust accumulation during the Holocene.

δ88/86Sr data published over the last few years suggest that continental waters are enriched with 88Sr as compared to the rocks in their drainage basins. In an attempt to understand this phenomenon, this study established the fractionation in the 88Sr/86Sr ratio during precipitation of continental carbonates (i.e., carbonates precipitated on land from surface, pedogenic, or ground waters), and evaluated the contribution of this process to the 88Sr-enrichment in rivers. For this, stable and radiogenic Sr isotopes (88Sr, 87Sr and 86Sr) were measured in calcite samples and their precipitating waters collected in various continental environments, such as soil, cave, streams and groundwater. The results indicate that continental carbonates are 88Sr-depleted relative to their precipitating waters, placing them as one of the most 88Sr-depleted reservoirs on earth. The average difference in δ88/86Sr values between waters and solid CaCO3 (tufas or speleothems) that they precipitate is Δ carb-water = − 0.218 ± 0.014 ‰ (1SD). An even larger fractionation ( e carb-water = − 0.285 ± 0.02 ‰ ) was measured in groundwater with particularly high carbonate-alkalinity and high carbonate precipitation rate that depleted ∼65% of the Sr in the groundwater, resulting in substantial 88Sr-enrichment in the residual dissolved Sr ( δ Sr 88 / 86 = 0.656 ‰ ). Results also suggest that pedogenic carbonate precipitation in soil profile removes 50–85% of the Sr from the recharging soil–water, thereby increasing the δ88/86Sr value of the soil-water from ∼ 0.18 ‰ to 0.3 ‰ – 0.6 ‰ . Similar 88Sr-enrichment was observed in drip water from a karst cave. A maximum removal flux of Sr into continental carbonates of about 20 Gmol(Sr)⋅y−1 is required to yield the reported 88Sr-enrichment in global rivers ( δ Sr 88 / 86 = 0.32 ‰ ) relative to their rock sources when using the fractionation factor derived in this study, Δ carb-water = − 0.218 ‰ , and the published δ88/86Sr composition of marine carbonates of 0.16‰. This surprisingly large flux requires that ∼40% of the originally weathered Sr should co-precipitate with continental carbonates. This calculation may suggest that CaCO3 precipitation is a significant mechanism in the continental Sr cycle. It is possible however that other mechanisms such as Sr uptake by plants or incongruent weathering of silicates, could also contribute to the riverine 88Sr-enrichment. Alternatively, the average δ88/86Sr value of marine carbonate rock sections undergoing weathering is higher than suggested in current literature. It is concluded that additional δ88/86Sr data on marine carbonate rock sections should be collected to resolve the enigma of the high value of riverine δ88/86Sr.

Archaeological structures are often filled with sediments and may serve as effective dust traps. The physical parameters and chemical composition of archaeological soils in hilltop ruins, ancient runoff-collecting terraces, and cleanout spoils of cisterns were determined in the Petra region in southern Jordan and the Northern Negev in Israel. Different types of ruins are characterized by certain soil structures, but could not be distinguished with regard to substrate composition. This reflects a predominance of aeolian processes for primary sedimentation, while fluvial processes seem to only re-distribute aeolian material. In the Petra region, the physical and chemical properties of all archaeological soils show a significant local contribution from associated weathered rocks. Compared to modern settled dust, archaeological soils in Southern Jordan are enriched with various major and trace elements associated with clays and oxide coatings of fine silt particles. This seems connected with preferential fixation of silt and clay by surface crusts, and a role of moisture in sedimentation processes as calcareous silt was found to be deposited in greater amounts when associated with precipitation. In contrast, the contribution of rocks is negligible in the Negev due to greater rock hardness and abundant biological crusts that seal surfaces. Archaeological soils in the Negev are chemically similar to current settled dust, which consists of complex mixtures of local and remote sources, including significant portions of recycled material from paleosols. Archaeological soils are archives of Holocene dust sources and aeolian sedimentation processes, with accretion rates exceeding those of Pleistocene hilltop loess in the Negev. Comparison with Pleistocene paleosols suggests that dust sources did not change significantly, but disappearance of snow could have reduced dust accumulation during the Holocene.

Benthic foraminifera-based transfer function models provide accurate sea-level reconstructions for shelf and coastal environments around the world. This study presents for the first time results of a foraminiferal transfer function aiming at the reconstruction of relative sea-level in the southeastern Mediterranean shelf during the past one million years. A Weighted Averaging-Partial Least Squares (WA-PLS) regression method was used for the development of the transfer function based on an extensive set of surface samples (modern training data set) from the study area. The transfer function was applied to three shelf sediment successions retrieved from Haifa Bay, Israel. The Modern Analog Technique (MAT) and the random TF test were used to investigate similarity between modern and fossil foraminiferal faunas, testing the reliability and significance of our model for paleowater depth reconstruction. The performance of the WA-PLS transfer functions suggests a strong relationship between the observed and estimated water depths in the modern data set with relatively precise reconstructions of 7.0 m (Root Mean Squared error of Prediction) over a water depth range of 3 to 80 m. The deepest paleo water depths were reconstructed for the earliest sea-level highstands recorded in the sediment records (MIS 27? and MIS 29?) in the down-faulted boreholes due to tectonic movements, whereas the younger interglacial sedimentary units (MIS 25?, 13, 11, 7, 5.5 and 1) were mostly deposited at

A subsurface sequence in Haifa Bay, the Levant basin, was studied for its clay mineralogy by X-ray diffraction (XRD) in order to examine the response of clay assemblages to sea-level changes and alternating environments over a long period, apparently longer than ever recorded before. The study was conducted on continuous cores of three boreholes that represent ~ 1 m.y. of very shallow (

This study presents the first in-depth analysis of properties, micromorphology, clay mineralogy, magnetic susceptibility, and general properties of Quaternary paleosols from two boreholes in Haifa Bay subsurface, whose chronostratigraphic position was determined previously. The current analytical results allowed us to identify the type, hydrologic regime, polygenesis, mode of pedosedimentary evolution, and some subsequent alterations of paleosols. The analogs of polygenic Haplo- and Rhodo-xeralf soils (Brown, Mollic, and Ortho-Hamra) are associated with marine isotope stages (MIS) 3.1, 5.4, 6 and 8.0 (or 7.4) and likely developed in response to a changing climate. Paleosols prior to MIS 12, yet difficult to attribute to specific MIS, are distinct from Hamra soils by striking mottling, poor preservation of argillic horizons, abundant deformations in microfabric, and overprinting processes of gley and calcium carbonate accumulation. It is assumed that calcification may have affected the earlier formed clay illuviation and amorphous features, and was related with marine/coastal groundwater interface. The older calcic gleyed paleosols of earlier Middle Pleistocene likely indicate that coastal paleogeography was characterized by both high discharge of the ancient Qishon River and a high water table. The thin section micromorphology is particularly valuable for refined paleopedological taxonomy. Identified Pleistocene paleosols including their type, hydrology and mode of evolution, are proposed to serve additional stratigraphic markers in coastal settings.

The diagenetic grade of a 2.7 km thick sequence of lower Palaeozoic marine sediments in the Tobolka 1 deep exploration borehole was investigated by analysing organic and mineral components and fluid inclusions embedded in vein minerals. The reflectance of organic matter ( R r %) increases down-section from values of about 0.77% at the top of the Devonian Srbsko Formation to values around 3% at the base of the Ordovician Letna Formation. In the Devonian and Silurian sediments the reflectance values of vitrinite-like and graptolite fragments (0.77–1.13% R r and 1.09–1.46% R r respectively) and the composition of fluid inclusions entrapped in vein minerals (CH 4 + CO 2 + complex saline solutions ± light gaseous hydrocarbons ± liquid petroleum; T h = 170–230 °C) collectively indicate organic maturation within the high-temperature part of the oil window to the wet gas stage. In the Ordovician sediments below 1000 m, chitinozoan reflectance values (1.38–3.03% R r ) and the CH 4 -dominated composition of the fluid inclusions ( T h = 250–310 °C) indicate a wet gas/condensate stage to an advanced dry gas stage. The clay mineral assemblage remains uniform throughout the whole succession and consists of illite, mixed-layered illite–smectite (IS), chlorite and kaolinite. Below 1400 m the illite content gradually increases down-hole, forming up to 45–55% of the clay fraction in the deeply-buried Ordovician sediments. Throughout the borehole, the IS displays uniformly low expandability (7–12 ± 3% of smectite layers) and an ISII ordering. The illite crystallinity broadly correlates with organic matter reflectance values and improves with depth (from 1.1 to 0.54° Δ2 θ according to the Crystallinity Index Standard (CIS) scale) indicating high-grade diagenesis to incipient anchimetamorphism. The chlorite crystallinity ( ChC index), however, shows no systematic correlations with depth. The combined evidence from organic matter, clay minerals and fluid inclusions points to maximum paleotemperatures of ~ 100–230 °C in the Silurian–Devonian strata, and up to ~ 250 °C or even higher in the Ordovician strata. Apatite fission track analysis (AFTA) data suggests that maximum heating occurred between 340 and 380 Ma, i.e. during Variscan orogenic deformations. These paleotemperatures and the degree of diagenesis may have been produced by a post-Middle Devonian burial or tectonic load that was subsequently eroded, or by higher paleogeothermal gradients, or by a combination of both.

The type and composition of freshwater and marine sediments are key factors in environmental research of (a) natural processes such as sediment transport and accumulation, biodiversity, and biogeochemical reactions within sediments and (b) evaluation of source and progress of contamination, as aquatic sediments act as a sink for nonorganic and organic toxic substances. Above certain levels, such substances could harm biological diversity and human health. Geochemical investigations of aquatic sediments in fluvial, lacustrine, estuarine, and marine environments are of fundamental interest for the assessment of natural ecosystems and the level of pollution that potentially harms them. Detailed determination of the chemical constituents of aquatic sediments assists in detecting sources of pollution as sewage, industry, agriculture, abandoned and active mines, landfills, harbor activities, and oil drilling [leakage]. In addition, natural anomalies may indicate mineral resources in a particular region. New methods and approaches for sampling and analysis are continuously being introduced in aquatic sediment research. More attention is given to qualitative and quantitative monitoring of sediment and sediment fluxes, which is regularly established in most European countries and many others worldwide. Unfortunately, uniform legislation of sediment quality [and load] still does not exist on an international level and in most countries does not exist even on the national level. Therefore, more attention should be given to further expansion of sediment monitoring and of establishing criteria for assessing sediment quality and legislative for toxic inorganic and organic pollutants.

The current study evaluates clay distribution in modern surface sediments, mainly soils, to which desert dust is a major contributor. The mineralogical composition of the clay fraction of seventy seven samples was analyzed by X-ray diffraction. Twenty nine soil and dust samples were also analyzed for their bulk chemical composition. The samples are settled dust, soils developed on various sedimentary rocks, stream and lake sediments. They were collected along a climate gradient from hyper-arid to Mediterranean regimes in Israel. The purpose of the study is to decipher the main factors that control variable clay distribution along this gradient including annual precipitation, substrate type and topography. The common clay composition for most samples, of all sources, is illite–smectite (IS) > kaolinite > illite. Trace amounts of chlorite, palygorskite, goethite and quartz might be present. Pedogenic processes are recognized even under arid climate where loessial soils display kaolinite depletion and more illitic IS phases than dust. Two main processes shape clay composition under a Mediterranean climate regime, regardless of the parent material. A smectitization process occurs in leached, low-permeable clayey soils, and reaches optimum evolution with ~ 90% smectite, or smectitic IS. This evolutionary trend is also recognized in poorly-drained soils of catenary chains that are related to other soil types like terra rossa, hamra and pale rendzina. Kaolinitization and apparently illite pedogenic formation occur in well-drained red Mediterranean soils of the terra rossa and hamra types to the detriment of smectitic IS phases of parent materials. In the most evolved terra rossa and hamra soils kaolinite becomes the principal mineral and illite is significantly enriched. Pedogenic evolution of the clay fraction mineralogical composition affects bulk chemical composition of most soil types. Clay inheritance from the bedrock is rather limited in leached soils. It is widely recognized in pale rendzina soils by the presence of smectite, or smectite and palygorskite, derived from late Cretaceous or Eocene chalks, respectively. Streams' clay composition, like that of dust, is fairly uniform, as streams average various sources across their drainage basins. However, composition variations can be attributed to local contribution from certain sources.

Benthic and planktonic foraminifera were studied in inner shelf sedimentary sequences in Haifa Bay, Israel. Three boreholes, taken at water depths from 5 to 14 m, spanning about the last 1 Ma, and a set of modern sediment samples used as modern analogue, were utilized for reconstructing palaeoenvironments and palaeobathymetry. The palaeoenvironmental data were used for assessing tectonic activity of the Carmel Fault, a branch of the Dead Sea transform that bounds the southern side of the bay. Quantitative analyses showed four biofacies: a fresh to brackish wetland environment, and three progressively deepening marine biofacies. Relative water depth ranges were estimated using changes in benthic foraminiferal assemblages, presence or absence of Ammonia sp. 1, and the percentage of planktonic foraminifera. The distribution of the biofacies suggests water depths no deeper than 15 m during most interglacial stages, water depths to 15–40 m during short transgressive phases of MIS 5.5, 7, 11 and 13, and water depth reaching 40–80 m in the earliest transgressive phases (MIS 27? and MIS 29?). The environmental conditions on both sides of the fault were quite similar along the succession. This suggests that the movements of the uplifted and down-faulted blocks have more or less coincided since about 1 Ma.

Catenary relationships of surface soils in the vicinity of kibbutz Shomrat in the Galilee coastal plain of Israel were studied including optically stimulated luminescence (OSL). The research provides new insights into the local pedogeomorphic history and confirms that the study area is of different age than the central coastal plain of Israel. The soil toposequence is composed of polygenic red Hamra (Rhodoxeralf) on the hilltop, a calcareous Rhodoxeralf (Husmas) on the middle slope, both older than 250 ka, and a complex pedosedimentary sequence in a lower position spanning Middle Pleistocene–Holocene OSL ages. The hilltop red Hamra is strongly reworked by soil burrowing animals, magnetically enhanced, and contains aged clay coatings and a few petrocalcic nodules. Micromorphology revealed a relict nature of cemented carbonate nodules and allowed us to establish a sequence of pedogenic episodes, e.g. rubification and clay illuviation that intermittently affected nodule growth and re-crystallization. All soils are dominated by interstratified illite–smectite, whose amount and expandability increase downhill. In the lowest topographic positions, soil development was compounded by additional fine-grained accumulation via eolian and slope processes which may have intensified during periods of geomorphic instability. Our data and interpretations suggest that to the north of Haifa Bay, coastal geomorphic surfaces are formed by late Mid-Pleistocene exhumed paleosol toposequences, which are sporadically overprinted by younger paleosols, and continue to function as presently active soils.

The stable isotope composition of strontium (the ratio 88 Sr/ 86 Sr expressed as δ 88/86 Sr) showed significant fractionation in mountain soils of the Judea Highland. In order to understand this phenomenon, we studied the elemental composition and the stable and radiogenic Sr isotopic composition in soil transects conducted from semi-arid (desert fringe) to wetter (Mediterranean) climate zones. These transects were selected because the degree of soil leaching depends on the amount of precipitation and the permeability of the underlying bedrock. These soils are the pedogenic products of leaching of the accumulated desert dust and the underlying carbonate bedrocks resulting in, among others, enrichment of the residual soils in Al-clays. A clear negative correlation was found between the δ 88/86 Sr and Al 2 O 3 (Al-clay content) values of the soils, the high δ 88/86 Sr-low Al 2 O 3 being the dust end-member. This preliminary study demonstrates the feasibility of using stable 88 Sr- 86 Sr isotopes as tracers of terrestrial weathering processes.

The sources and routes of transport of fine detritus material ( FDM ) to the lakes filling the late Quaternary Dead Sea basin were studied by petrographic, mineralogical, grain size, chemical and Sr–Nd isotope analyses on sediments of the late Quaternary lacustrine formations, including river flood material, dust, and loess from the lake watershed. The lacustrine formations comprise two sedimentary facies: one that consists of alternating laminae of primary aragonite and silty-detritus material ( aad facies ), and another that consists mainly of laminated detritus particles and generally lacks aragonite ( ld facies ). The aad facies characterizes the glacial intervals (e.g. MIS2 and 4) when lake levels were high, while the ld facies characterizes interglacials (e.g. MIS1, 5) and warmer glacial intervals (e.g. MIS3), when lake levels were low. The detritus of both aad and ld facies show similar mineralogy: mainly quartz and calcite grains with minor feldspars and clays, but distinct grain-sizes (8–10 μm and 50–60 μm, respectively), and distinct 87 Sr/ 86 Sr and eNd (0.711–0.712 and ∼−7 to −8, versus 0.709–0.710 and ∼−5, respectively). The aad and ld FDM comprise desert dust of mixed granitic – basaltic composition that was blown from the Sahara desert and from the Nile delta to the northern Negev desert (e.g. the loess deposits) and the Judean Mountains bordering the Dead Sea basin, mainly during glacial intervals along with enhanced Mediterranean rain fronts. The aad FDM reflects an enhanced transport of Saharan granitic dust to the vicinity of the lake mainly during glacials. The ld FDM was recycled from the loess surface cover of the Negev desert mainly during interglacials and warm glacial intervals.

The current detailed chronostratigraphic framework of the last 1 Ma of an eastern Mediterranean sequence (Haifa Bay, Israel) aims to examine the relative roles of sea-level changes, climate and tectonics. Seven continuous marine cores, up to � 120 m long, were recovered from shallow water depths. The cores were dated by optically stimulated luminescence, 14 C, magnetostratigraphy, 230 Th/ 234 U, 26 Al/ 10 Be, occurrence of index fossils and correlated to the global sea-level curve and Marine Isotope Stages (MIS). The sedimentary sequence accumulated during the last ca. 1.0 Ma consists of 21 transgression-regression units with hiatuses between them. Five marine/ terrestrial cycles, which occur in the lower part of the sequence, are attributed to the Jaramillo subchron and the Brunhes-Matuyama boundary, and correspond to MIS 29-21. The top � 50 m includes three sedimentary cycles deposited in the last ca. 400 ka. The regressive phases during this interval correspond to Glacial MIS 8, 6 and 2, while the transgressions correspond to Interglacial MIS 11, 7, 5 and 1. Thus, for the first time, this study documents the longest Quaternary succession dated so far in a key area of the Levant, sensitive to global history of sea-level changes and glacial/interglacial fluctuations. Copyright # 2012 John Wiley & Sons, Ltd.

Altered crystalline rocks occur at the peneplain exposed in southern Israel and in other localities across North Africa and Arabia where they underlie an extensive blanket of Cambro–Ordovician sandstones. This study focuses on the petrography, mineralogy and geochemistry of top basement rocks of the northern Arabian-Nubian Shield. The altered rocks are shown to be weathering profiles that can be subdivided into three horizons interpreted as apparently unweathered granite, or saprock, which grades upwards to a saprolite, topped by a thin clayey plasmic zone. The plasmic zone is enriched in iron and aluminium and is depleted in silicon, calcium, magnesium and potassium relative to the underlying saprolite. The chemical index of alteration increases upward, but does not exceed 90 and, therefore, lags behind values observed in strongly leached present-day tropical soils. Petrographic examinations reveal iron mobility under local fluctuating redox conditions, similar to modern and Proterozoic soils. A variety of birefringence fabrics induced by shrinkage and expansion of clays during wetting and drying cycles and clay illuviation strongly indicate pedogenic processes rather than a post-depositional alteration. Illite and ordered illite-smectite phases coexist with smectitic illite-smectite in the lower part of the saprolite and with kaolinite in the plasmic zone, in line with increasing chemical index of alteration. Observations are in accordance with the current profile being a remnant of a thick weathering profile whose top was truncated by fluvial incision just prior to deposition of the overlying Early Cambrian sequence. A previously documented Devonian thermal event reaching temperatures of at least 200� C overprinted the studied rocks. During burial diagenesis, illitization affected original smectite rather than kaolinite. However, in spite of the elevated temperatures, illitization was incomplete implying restricted potassium addition. The sub-Cambrian weathering reflects warm and humid conditions in a tropical or sub-tropical climate, in line with several plate reconstructions placing Israel at low latitudes during Cambrian time.

Rock quarrying and processing is a source of coarse and fine particulate matter, which is transported by wind to the quarry surroundings and may have an environmental impact. The current study evaluated the possible contribution of dust from such a pollution source, a limestone quarry in north Israel, during the dry summer season. Accumulated dust and total suspended particulate matter were collected following an analysis of the prevailing synoptic conditions to evaluate the background dust, its origin and expected mineralogical and chemical properties. We performed comparative gravimetric, chemical and mineralogical analyses between sites lying upwind and downwind of the limestone quarry and defined the background dust and its origin. During the summer season under the Persian trough synoptic system, mineral dust in the research area was mostly composed of material similar to the local lithosphere, mainly carbonate rocks, and thus to the quarried rock. High concentrations of some trace metals, on the other hand, were related to remote sources, as has been documented previously for the Persian trough synoptic condition. Gravimetric analysis found 300 to 400% more accumulated dust and up to 400% more total suspended particulate matter about 1 km downwind versus upwind of the quarry. Mineralogical and chemical analyses of the dust samples, and of the quarried rock, revealed that the downwind site is enriched, relative to the upwind site, in the major component of the quarried rock–calcite, and that both sites are enriched in the major components of background dust.

There is interest in studying interactions between organic modifiers and raw commercial clays aiming the production of low-cost “organoclays”. In this study we report the interaction between berberine — a monovalent organic cation — and three commercial bentonites and a Turkish zeolite. The Turkish zeolite exhibited adsorption at values of 5–10% of the cation exchange capacity (CEC) with no neutralization of the particles. Adsorption of the organo-cation on Egyptian bentonite, Volclay KWK and Pure-Flo B80, was above the CEC of the bentonites, yielding neutral and even slightly positively charged particles. Electron microscopy and X-ray diffraction results showed expansion of the basal spacing of the smectite. Such low-cost organo-bentonites might be suitable for environmental applications as removal of pollutants, drug and pesticides delivery, or water treatment. Application in turbidity reduction of industrial effluents is demonstrated.

Suspended atmospheric particles were collected in Israel in order to identify their nature and relationships with the major synoptic-scale circulation patterns. The particles were analyzed for their major and trace element concentrations and mineralogical composition. Samples were collected during three synoptic systems associated with desert dust storms: Red Sea trough, Sharav cyclone and cold depression, and during deep and shallow modes of Persian Gulf trough, which prevails in the summer months and is not associated with dust storms. All samples mostly contain particles smaller than 2 μm. The suspended desert dust is composed primarily of illite–smectite and calcite. Some indicative secondary minerals were found for each of the dust transporting synoptic systems (e.g., palygorskite for Red Sea trough). The bulk chemistry data support the mineralogical observations and reveal additional chemical signatures of each dust transporting system. For instance, Red Sea trough samples have significantly higher Ca/Al and Ca/Mg in the carbonate and Mg/Al in Al-silicate fraction than cold depression samples. Nevertheless, Sharav cyclone samples have intermediate values in spite of the fact that the source of the dust during these conditions is similar to cold depression (i.e., North Africa). Even though differences in the chemical and the mineralogical composition of desert dust do exist, this study reveals their overall chemical and mineralogical similarities. In contrast to the synoptic systems that carry desert dust, the inorganic fraction of the Persian Gulf trough samples contains significant amount (up to 50%) of non-mineral material that has a pronounced chemical signature in terms of major element concentrations (e.g., Al, Ca, Mg, Na, S) implying their anthropogenic nature, probably from countries around the Black Sea. This striking finding is indicative for atmospheric pollution in the Eastern Mediterranean region during the summer.

Grain size analyses of three hilltop, primary eolian loess sequences in the Negev desert, southern Israel, show a bimodal grain-size distribution at 50–60 μm and 3–8 μm. Using analyses of mineralogy and OSL ages we demonstrate that the coarse mode is composed mostly of quartz grains and its relative magnitude increases regionally with time, suggesting an enhancement of a time-transgressive proximal dust source compared to a distal, Saharan fine-grain dust. The only proximal dust source for large amount of coarse silt quartz grains is the sands that advanced into Sinai and the Negev concurrently with the loess accretion during the late Pleistocene as a result of the exposure of the Mediterranean shelf. We therefore propose that the coarse silt quartz grains were formed through eolian abrasion within the margins of an advancing sand sea. This relationship between desert sand seas as a source for proximal coarse dust and desert margin loess deposits can be applicable to other worldwide deserts such as Northern Africa, China and Australia.

International audience; The purpose of the current study was to quantitatively explore the dynamics of clay pedogenesis in red-brown soils of the terra-rossa type and associated soils (mainly Rhodoxeralfs) of the Mediterranean region with respect to bedrock and dust composition, and the impact of the vegetation-translocated elements silicon and potassium. Fifteen non-cultivated, shallow and leached mountain pedons were sampled in Israel along three transects that represent various rainfall ranges and bedrock lithologies. Bulk and clay fraction chemical and mineralogical compositions, as well as grain size, were determined. Quantitative relative analysis of clay minerals displayed a large variability that was largely affected by leaching. Leaching was dependent on rainfall amount and bedrock/soil permeability. In general, if the better soils were drained and leached the higher were the amounts of both kaolinite and illitic phases. Soil clay assemblages lay between two mineralogical end members: one with dominance of smectite and the second with high values of kaolinite and illitization parameters. Potassium and silicon were mobile in soils relative to aluminum, but under high rainfall or certain vegetation, translocation by vegetation reached a degree that promoted illite or smectite formation. Local combinations of rainfall, bedrock/soil permeability, and vegetation translocation of potassium and silicon dictated a large variability in clays, including illite formation, within a restricted group of red-brown Mediterranean soils.

The transition between the Permian and the Triassic systems in Israel is evident only in the subsurface. Two cores, from the Makhtesh Qatan 2 (core 9) and Avedat 1 (core 5) drillholes, in which the Permian–Triassic boundary was found marked by a fungal event, were sampled at close intervals and analysed for palynological, petrographical, mineralogical, chemical, and isotopic properties. Three palynozones were recorded: Lueckisporites virkkia Zone (Late Permian), Fungal Event, and Endosporites papillatus Zone (Early Triassic). The Fungul Event occurs in a narrow interval of ∼ 1 m and contains almost exclusively fungal remains and recycled woody particles. The two cores consist of laminated sediments, mainly siliciclastic, that were deposited in very shallow to restricted marine environments with a minor presence of evaporites and no bioturbation. Green glauconitic material and framboidal pyrite suggest suboxic conditions even in the shallow waters; reddish brown particles and plant fragments derived from nearby soils, now outcropping on the northeast side of the Dead Sea. These materials, as well as recycled brown glauconitic grains, suggest a drop in sea level and intense erosion before sedimentation, which was apparently continuous. Major and trace element compositions, including rare-earth elements, do not exhibit any particular pattern that might be related to the Fungul Event or to other core intervals. The rare-earth element patterns are basically normal and their concentration correlates with the clay content, reflecting the provenance of the Arabo-Nubian Massif and its sedimentary rims. Iridium results were mostly at the background level, and therefore the two distinct anomalous values are inconclusive. Microspherules, mainly of ∼ 2 μm size and Al–Si composition, were observed in a few samples in both cores. Their origin could not be determined, though they are considered to be natural. There was no evidence for shocked quartz. δ13Corg excursion exhibits a marked negative shift in both cores, just below the Fungal Event. The lowest values, − 37‰ and − 42‰, are among the lowest ever recorded near the Permian–Triassic boundary and suggest large-scale release of methane-hydrates.

Authigenic K-feldspar was investigated in two Albian to Turonian sections in Israel using K-Ar and Ar-Ar dating, X-ray diffraction, scanning electron microscopy and chemical analysis. Both sections comprise a similar succession of shallow-marine limestones, dolomites and marls, with some sandstone and shale beds of continental origin. The HCl-insoluble residue fraction of the studied samples consists of clays, quartz, feldspars, goethite and trace amounts of heavy minerals. Most of the insoluble residues have a relatively high K-feldspar content that has an adularia habit and is concentrated in the 4–7 µm size fraction. The authigenic origin of the K-feldspar in the fine silt fraction is indicated by its high content relative to quartz, the uniform and idiomorphic shape of the crystals and its limited size range. Of the fine silt (4–7 or 4–10 µm) separates, 40% have ages that are similar to stratigraphic ages within the analytical and biostratigraphic errors. Ar-Ar dating of a fine silt fraction with 94% K-feldspar (4–10 µm, sample GYP 7) yields a plateau age identical to the total gas age and similar to the stratigraphic age. These results indicate that the K-Ar age is not a mixture between detrital and late diagenetic K-feldspar ages, but is rather an age of formation within a few million years after deposition. It is suggested that the early formation of the K-feldspar was associated with dolomitization and was induced by residual brines as part of a reflux process.

Sediments from Lunkaransar dry lake in northwestern India reveal regional water table and lake level fluctuations over decades to centuries during the Holocene that are attributed to changes in the southwestern Indian monsoon rains. The lake levels were very shallow and fluctuated often in the early Holocene and then rose abruptly around 6300 carbon-14 years before the present ( 14 C yr B.P.). The lake completely desiccated around 4800 14 C yr B.P. The end of this 1500-year wet period coincided with a period of intense dune destabilization. The major Harrapan-Indus civilization began and flourished in this region 1000 years after desiccation of the lake during arid climate and was not synchronous with the lacustral phase.

The upper surface of alluvial terraces at Mt. Sedom, Israel are covered with a biogenic crust populated by filamentous cyanobacteria. The cyanobacteria expand when wet and shrink when dry, forming when time passes cracks in the soil surface in the form of polygons. These polygons are smaller than those formed by shrinking of the mineralogical component of the substratum. Continuing to grow and expand laterally the cyanobacteria cause upfolding of the polygon margins which in time become populated with cyanophilous lichens. The lateral growth accompanied by increasing trapping of airborne dust in the cracks of thalli of cyanophilous lichens leads to the development of microridges along the former upturned margins of cracks. Increasing water storage in the depressions of the surface with augmenting roughness ameliorates the moisture regime by decreasing water runoff from the soil surface. Cyanobacteria of the early stages of colonization occur at the drought-latent stage below the surface of the flat soil and emerge phototactically when sufficiently wetted. Their fronds are green. The microbionts on the elevated terraces representing progressive, older stages of colonization are situated above the rugged-surfaced soil and have dark thalli or fronds. The number of microbiont species, chlorophylla, and polysaccharide content of the crust increase from the young to the old terrace. Calcite content, compaction, and linear structure increase too. All these quantitative changes lead us to regard the different stands as parts of microbiotic succession. We recommend the use of the micro-geomorphological structures as age indicators which are correlated here with the relative time sequence system of alluvial terraces in other places, even if they are not in such an obvious chronosequence.

An unusual form of niter–monomineralic potassium nitrate stalactites (up to 90 cm long) and stalagmites–was discovered in a limestone cave in the Lower Galilee, Israel. Chemical and nitrogen isotope analysis of the deposit and potential source materials, together with hydrologic evidence, suggest the following special circumstances for its formation. Very high precipitation during the winter of 1991/92 resulted in rapid transmission of rain water, with low dissolved ion concentrations, through wide fissures in the limestone; this led to the saturation of excreta‐rich cave floor sediments that are normally dry. Resulting solutions rich in potassium nitrate dripped into an underlying cave close to its large entrance, where the cave humidity is largely influenced by the humidity of the outside air. For most of the time the humidity was sufficiently low to cause evaporative oversaturation and deposition of niter from the dripping solutions. When dripping decreased, however, occasional periods of high humidity...

The Middle East is one of the regions in the world where relatively high concentrations of atmospheric particulate matter (PM) have been detected frequently. It has been suggested that PM levels in the Middle East are present at levels that lead to adverse health effects and to poor visibility. In the current study, we summarize results published by our group over the last decade and introduce new data which demonstrate the extent of trans-boundary PM transport, and the fact that synoptic conditions control its chemical and mineralogical composition and might also affect its toxicity.

In this study we combine Pb isotopes, Pb, Ni, Cu, Zn, and several major metal concentrations, identification of the aerosol particles, and synoptic and back trajectory analyses to obtain direct evidence for the extent and nature of mixing between Middle Eastern and European sources emissions of metals and aerosols. During the summer months aerosols collected in Israel are highly polluted by metals (EF(Ni) = 120, EF(Cu) = 320, EF(Zn) = 30, EF(Pb) = 540; average values). The fraction of European Pb of mostly industrial sources is 61 +/- 21% in Jerusalem, and the fraction of European Cu, Zn, Ni, and aerosols should be on the same order. Whenever a steep pressure gradient is built between the barometric trough originating from the Persian Gulf and the subtropical ridge along the African coast, stronger westerly winds and cooler temperatures (deep Persian Trough) prevail overthe Middle East, and higher amounts of European pollution are observed in the atmosphere (74 +/- 13%). On the other hand, when the Persian Trough is in its shallow mode, the proportion of European pollution is lower (45 +/- 18%, based on Pb isotopes). This study demonstrates that atmospheric pollution over the East Mediterranean region during the summer is influenced not only by local atmospheric dispersion conditions but also by the ability of the atmosphere to inherit a significant proportion of pollutants from European sources.

DTA is one of the preferred methods used to determine quartz quantitatively. It is well known that for quartz of small particle size (less than 0.5gm) large discrepancies are found between X-ray and thermal results, raising doubts as to the reliability of the DTA method. However we show that the height of the DTA high-low inversion quartz peak is a function of both the amount of quartz in the sample and of the crystallinity index (CI) of quartz as defined by Murata and Norman [1]. DTA can be used in a routine manner for the quantitative determination of quartz for well crystallized quartz (CI above 8); for other cases, special curves with appropriate standards have to be prepared, and for poorly crystallized quartz (CI less than 3), DTA cannot be used.

Kerogen and humic acid extracted from Eocene chalks and cherts display composition variations which do not follow normal thermal maturation trends. Decrease in the H/C ratio is followed by an increase of the O/C, S/C and N/C ratios; and the 12 C is also enriched. The humic acids are always heavier in their δ 13 C composition than the kerogens extracted from the same samples, their H/C, O/C and S/C ratios are usually higher and their structure is more aliphatic and less aromatic. The compositional trends observed in the humic acids and kerogens apparently result mostly from increased microbial oxidation of aliphatic chains into carboxyl groups by sulfate-reducing bacteria. This process is corroborated by infrared spectra which reveal a negative correlation between aliphatic and oxygen-containing groups, coinciding with the negative H/C-O/C relationship. The change from humic acids to kerogen, on the other hand, is the result of thermal maturation accompanied by microbial oxidation. Since the chert and chalk samples reflect the same evolution trends it appears that the microbial oxidation affected the organic matter prior to chertification.