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1.
Accurate reconstruction of the paleo-Mojave River and pluvial lake (Harper, Manix, Cronese, and Mojave) system of southern California is critical to understanding paleoclimate and the North American polar jet stream position over the last 500 ka. Previous studies inferred a polar jet stream south of 35°N at 18 ka and at ~ 40°N at 17–14 ka. Highstand sediments of Harper Lake, the upstream-most pluvial lake along the Mojave River, have yielded uncalibrated radiocarbon ages ranging from 24,000 to > 30,000 14C yr BP. Based on geologic mapping, radiocarbon and optically stimulated luminescence dating, we infer a ~ 45–40 ka age for the Harper Lake highstand sediments. Combining the Harper Lake highstand with other Great Basin pluvial lake/spring and marine climate records, we infer that the North American polar jet stream was south of 35°N about 45–40 ka, but shifted to 40°N by ~ 35 ka. Ostracodes (Limnocythere ceriotuberosa) from Harper Lake highstand sediments are consistent with an alkaline lake environment that received seasonal inflow from the Mojave River, thus confirming the lake was fed by the Mojave River. The ~ 45–40 ka highstand at Harper Lake coincides with a shallowing interval at downstream Lake Manix.  相似文献   

2.
Sedimentological and geomorphological studies of terraces around Lake Van (1647 m) provided a preliminary framework for lake‐level variations. The elevations of terraces and past lake level were measured with a differential global positioning system. A chronology is developed using 234U/230Th dating of travertines, 39Ar/40Ar dating of pyroclastites and 14C dating of organic matter. Facies and stratigraphic correlations identify four transgressions (C1′, C1″, C2′ and C2″), each followed by a regression which ended with low lake levels that caused river incision and terrace formation. Evidence of the oldest transgression (C1′) is found in the uppermost reaches of valleys up to 1755 m, an altitude higher than the present lake threshold (1736 m). This C1′ transgression may be related to pyroclastic flows which dammed an outlet located in the western part of the lake basin and which is dated to before 105 ka. After 100 ka, a second transgression (C1″) reached 1730/1735 m, possibly related to a younger ignimbrite flow, in association with high water inflow (warm and/or wetter conditions). The two younger transgressions reached 1700–1705 m. The first one (C2′) is dated to 26–24.5 cal. ka BP and the second one (C2″) to 21–20 cal. ka BP. Available data suggest that the long‐term lake‐level changes responded mainly to climate oscillations. Additional events such as river captures caused by volcanic falls filling valleys, tectonism, erosion and karstic diversion may have impacted these long‐term lake‐level changes. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

3.
Predominantly laminated lake sediments from a saline closed‐basin lake on the northeastern Tibetan Plateau were investigated using a multi‐proxy approach (14C‐accelerator mass spectrometry dating, smear‐slide analysis, loss on ignition, grain size, X‐ray diffraction, elemental concentration, ostracod assemblages, stable isotopes of ostracod shells) to trace the regional environmental and climatic history in the Lateglacial and Holocene. Before about 15 cal. ka BP, small saline water bodies probably filled the basin under unstable cold and harsh environmental conditions. Soon after about 14.9 cal. ka BP, a relatively deep saline lake was established, probably as a result of runoff from melting snow, ice and frozen ground in the lake's catchment. Large changes in flux of aeolian material to the lake were recorded during this initial period of formation of Lake Kuhai. Highest lake levels, a low sediment accumulation rate and less saline conditions were maintained between about 12.8 and 7.1 cal. ka BP when the aeolian influx diminished significantly. After about 7.1 cal. ka BP, the aeolian influx remained at a moderate level apart from a strongly increased dust delivery to the lake between about 6.1 and 5.4 cal. ka BP and a minor short‐lived period of slightly enhanced aeolian influx at about 2.7 cal. ka BP. The strongly enhanced dust input to the lake between 6.1 and 5.4 cal. ka BP represented the largest influx of aeolian material to Lake Kuhai during the entire Holocene. However, evidence for climatic deterioration during this period is not seen at most other palaeoclimate sites on the Tibetan Plateau, but instead a significant increase in aridity has been recorded at numerous sites in the northern foreland of the Tibetan Plateau and on the Chinese Loess Plateau. The large dust input to Lake Kuhai between 6.1 and 5.4 cal. ka BP probably did not result from a severe climate deterioration on the Tibetan Plateau itself, but from the pronounced aridity in its northern and eastern foreland. In contrast, the increase in dust influx about 2.7 cal. ka BP seems to correspond to a brief warming spell recorded at other sites on the Tibetan Plateau too. A slight increase in lake level and decrease in salinity after about 0.6 cal. ka BP suggests a slightly higher effective moisture during the final lake stage, accompanied by a somewhat larger dust influx. This apparent contradiction possibly results from enhanced human activities on the northeastern Tibetan Plateau during the last 600 years. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

4.
Photosynthetic pigments and other indicators of phytoplankton were analyzed in a dated undisturbed sediment core obtained from the southern basin of Lake Baikal to reveal temporal changes in the phytoplankton community in the lake through the last glacial/post-glacial transition. The sedimentation age of the core spans the last 24 14C ka. Chlorophyll a, its derivatives, carotenoids and total organic carbon (TOC) started to increase after 15 14C ka, and the onset of biogenic silica occurred at 10 14C ka. This indicated that the post-glacial growth of diatoms was preceded by that of other phytoplankton groups. In the record of the pigments and TOC, a temporary decrease was observed in the period 11.5–10.5 14C ka, corresponding to the Younger Dryas cold period. The similarity found between the depth profiles of pyropheophytin a and steryl chlorin esters formed through predation of phytoplankton by zooplankton and that of TOC suggested the important contribution of fecal pellets to sedimentary organic matter in the lake.  相似文献   

5.
Research on abrupt paleoclimatic and paleoenvironmental change provides a scientific basis for evaluating future climate. Because of spatial variability in monsoonal rainfall, our knowledge about climate change during the mid-to lateHolocene in southern China is still limited. We present a multi-proxy record of paleoclimatic change in a crater lake, Lake Shuangchi. Based on the age-depth model from 210 Pb, 137 Cs and AMS14 C data, high-resolution mid-to late-Holocene climatic and environmental records were reconstructed using multiple indices(TOC, TN, C/N, δ13 C and grain size). Shuangchi underwent a marked change from a peat bog to a lake around 1.4 kaBP. The C3 plants likely dominated during 7.0–5.9 ka and 2.5–1.4 kaBP, while C4 plants dominated between 5.9–3.2 and 3.0–2.5 kaBP. Algae were dominant sources of organic matter in the lake sediments after 1.4 kaBP. Several intervals with high concentrations of coarser grain sizes might be due to flood events. These results reveal that several abrupt paleoclimatic events occurred around 6.6 ka, 6.1 ka, 5.9 ka, 3.0 ka, 2.5 ka and 1.4 kaBP. The paleoclimatic change recorded in the lake may be related to the migration of the Intertropical Convergence Zone(ITCZ) and El Ni?o-Southern Oscillation(ENSO) activity.  相似文献   

6.
博斯腾湖湖泊沉积物光释光年代测量*   总被引：2，自引：0，他引：2  
使用光释光年代学的单片再生法测量了博斯腾湖沉积剖面中碳酸盐泥及粉砂质泥底部的浅湖相灰色粉细砂和风成沙的年龄,对剖面上部碳酸盐层中陆生植物残体进行了AMS 14 C测年。通过不同测片的等效剂量(De)值的分布状况评价了样品的晒褪程度,选择不随灵敏度校正后的自然释光信号变化的相对集中的等效剂量(De)值计算了样品的埋藏年龄。通过这些年龄结果的对比,发现石英矿物的OSL年龄和AMS 14 C年龄在地层上是一致的,表明尽管在浅湖相细砂中存在不完全晒褪,但根据相对较小而集中的De值计算得到的年龄结果是可靠的。这些年龄结果和地层资料揭示末次冰消期以来至早全新世,博斯腾湖处于无水干盆地向深水湖泊转化的浅水湖泊状态,现代深水博斯腾湖大约形成于距今8ka前后。  相似文献   

7.
A 10.5 m core from Changeable Lake in the Severnaya Zemlya Archipelago just north of the Taymyr Peninsula intersects ca. 30 cm of diamicton at its base, interpreted as a basal till. Because the upper 10.13 m of this core consists of non‐glacial sediments, a maximum numeric age for these non‐glacial sediments would provide a clear lower limit to the timing of the last glaciation in the area of Changeable Lake. Radiocarbon (14C) dating of several materials from this core yielded widely scattered results. Consequently we applied photonic dating to sediments above the diamicton. The experimental single‐aliquot‐regenerative (SAR) dose fine‐grain method was applied to two samples, using the ‘double SAR’ approach. With one exception, these fine‐grain SAR results and the results of application of the SAR method to sand‐sized quartz grains from two samples, at ca. 9.95 m and ca. 10.05 m depth, are discrepant with age estimates from the multi‐aliquot infrared‐photon‐stimulated luminescence (IR‐PSL) method applied to fine grains. Multi‐aliquot IR‐PSL dating of 10 samples produces ages increasing monotonically from ca. 4 ka at 2 m to 53 ± 4 ka at 9.97 m. These self‐consistent multi‐aliquot IR‐PSL ages, along with limiting 14C ages of >47 ka at ca. 10 m, provide direct evidence that glacial ice did not advance over this lake basin during the Last Glacial Maximum, and thus delimit the northeastern margin of the Barents–Kara Sea ice‐sheet to somewhere west of this archipelago. The last regional glaciation probably occurred during marine isotope stage (MIS) 4 or earlier. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

8.
Seismostratigraphical studies of the 11.8‐km2‐large and ~140‐m‐deep Lake Bolshoye Shchuchye, Polar Ural Mountains, reveal up to 160‐m‐thick acoustically laminated sediments in the lake basin. Using a dense grid of seismic lines, the spatial and temporal distributions of the sedimentary history have been reconstructed. Three regional seismic horizons have been identified and correlated with the well‐dated 24‐m‐long sediment core retrieved from the lake. Isopach maps constructed from the seismic data show four phases of sedimentation. A contour map of the deepest regional seismic reflector represents the earliest hemipelagic sedimentation in the lake. Three contour maps represent time intervals covering the last 23 cal. ka based on the well‐dated core stratigraphy from the lake. The detailed time constraints on the upper stratigraphical units in the lake allow calculation of the lake's development in terms of sediment fluxes and the denudation rates from the Last Glacial Maximum (LGM) to the present. The sedimentation in Lake Bolshoye Shchuchye has been dominated by hemipelagic processes during at least the last 24 cal. ka BP only locally interrupted by delta progradation and slope processes. A major shift in the sediment accumulation at c. 18.7 cal. ka BP is interpreted to mark the end of the local glacial maximum, greatly reduced denudation and the onset of the deglaciation period; this also demonstrates how fast the glaciers melted and possibly disappeared at the end of the LGM. The denudation rate during the Holocene is only a fifth of the LGM rate. The age of the oldest stratified sediments in Lake Bolshoye Shchuchye is not well constrained, but estimated as c. 50–60 ka.  相似文献   

9.
Models of factors controlling late Pleistocene pluvial lake-level fluctuations in the Great Basin are evaluated by dating lake levels in Jakes Valley. “Jakes Lake” rose to a highstand at 13,870 ± 50 14C Yr B.P., receded to a stillstand at 12,440 ± 50 14C yr B.P., and receded steadily to desiccation thereafter. The Jakes Lake highstand is roughly coincident with highstands of lakes Bonneville, Lahontan and Russell. The rise to highstand and recession of Jakes Lake were most likely controlled by a storm track steered by the polar jet stream. The final stillstand of Jakes Lake helps constrain timing of northward retreat of the polar jet stream during the Pleistocene-Holocene transition.  相似文献   

10.
Thorium-230 dating on saline of the Lower Salt unit in pluvial Searles Lake, California, shows that this unit was formed between 24,500 and 32,000 years ago. The initial apparent 14C age of the lake is estimated to be about 900 years. After correcting for nonradiogenic 230Th and for the initial 14C age, excellent agreement between 230Th and 14C ages is obtained. The reliability of 230Th dating on salt deposit opens a new way for continuation of absolute chronology below the Lower Salt in Searles Lake.  相似文献   

11.
Thorium-230 dating on saline of the Lower Salt unit in pluvial Searles Lake, California, shows that this unit was formed between 24,500 and 32,000 years ago. The initial apparent 14C age of the lake is estimated to be about 900 years. After correcting for nonradiogenic 230Th and for the initial 14C age, excellent agreement between 230Th and 14C ages is obtained. The reliability of 230Th dating on salt deposit opens a new way for continuation of absolute chronology below the Lower Salt in Searles Lake.  相似文献   

12.
The Bonneville Basin is a continental lacustrine system accommodating extensive microbial carbonate deposits corresponding to two distinct phases: the deep Lake Bonneville (30 000 to 11 500 14C bp ) and the shallow Great Salt Lake (since 11 500 14C bp ). A characterization of these microbial deposits and their associated sediments provides insights into their spatio‐temporal distribution patterns. The Bonneville phase preferentially displays vertical distribution of the microbial deposits resulting from high‐amplitude lake level variations. Due to the basin physiography, the microbial deposits were restricted to a narrow shoreline belt following Bonneville lake level variations. Carbonate production was more efficient during intervals of relative lake level stability as recorded by the formation of successive terraces. In contrast, the Great Salt Lake microbial deposits showed a great lateral distribution, linked to the modern flat bottom configuration. A low vertical distribution of the microbial deposits was the result of the shallow water depth combined with a low amplitude of lake level fluctuations. These younger microbial deposits display a higher diversity of fabrics and sizes. They are distributed along an extensive ‘shore to lake’ transect on a flat platform in relation to local and progressive accommodation space changes. Microbial deposits are temporally discontinuous throughout the lake history showing longer hiatuses during the Bonneville phase. The main parameters controlling the rate of carbonate production are related to the interaction between physical (kinetics of the mineral precipitation, lake water temperature and runoff), chemical (Ca2+, Mg2+ and HCO3? concentrations, Mg/Ca ratio, dilution and depletion) and/or biological (trophic) factors. The contrast in evolution of Lake Bonneville and Great Salt Lake microbial deposits during their lacustrine history leads to discussions on major chemical and climatic changes during this interval as well as the role of physiography. Furthermore, it provides novel insights into the composition, structure and formation of microbialite‐rich carbonate deposits under freshwater and hypersaline conditions.  相似文献   

13.
Based on geological and archaeological proxies from NW Russia and NE Estonia and on GIS‐based modelling, shore displacement during the Stone Age in the Narva‐Luga Klint Bay area in the eastern Gulf of Finland was reconstructed. The reconstructed shore displacement curve displays three regressive phases in the Baltic Sea history, interrupted by the rapid Ancylus Lake and Litorina Sea transgressions c. 10.9–10.2 cal. ka BP and c. 8.5–7.3 cal. ka BP, respectively. During the Ancylus transgression the lake level rose 9 m at an average rate of about 13 mm per year, while during the Litorina transgression the sea level rose 8 m at an average rate of about 7 mm per year. The results show that the highest shoreline of Ancylus Lake at an altitude of 8–17 m a.s.l. was formed c. 10.2 cal. ka BP and that of the Litorina Sea at an altitude of 6–14 m a.s.l., c. 7.3 cal. ka BP. The oldest traces of human activity dated to 8.5–7.9 cal. ka BP are associated with the palaeo‐Narva River in the period of low water level in the Baltic basin at the beginning of the Litorina Sea transgression. The coastal settlement associated with the Litorina Sea lagoon, presently represented by 33 Stone Age sites, developed in the area c. 7.1 cal. ka BP and existed there for more than 2000 years. Transformation from the coastal settlement back to the river settlement indicates a change from a fishing‐and‐hunting economy to farming and animal husbandry c. 4.4 cal. ka BP, coinciding with the time of the overgrowing of the lagoon in the Narva‐Luga Klint Bay area.  相似文献   

14.
The Provo shoreline of Lake Bonneville formed following the Bonneville flood, and, based on previous dating, was formed during a period of overflow from about 17.5 to 15.0 cal. ka. In many places the Provo shoreline consists of a pair of distinct shorelines, one ～3 m higher than the other. We present data from two cuts through double beaches to show that the upper beach is younger and represents sedimentation after a lake‐level rise. In addition, the lower beach deposits are internally stratified by beds that suggest three more lake‐level rises during its development. The Provo beach complex thus appears to have been built during rising lake levels, which can be explained by rises in the overflow threshold by sequential landslide deposition. Evaluation of beach altitudes demonstrates that the two beach crests throughout the Bonneville basin experienced equivalent rebound from removal of the lake load, and therefore they formed after the rebound associated with the Bonneville flood occurred in early Provo time. However, radiocarbon ages on gastropods collected within the beach deposits suggest both that the sequence of five beach deposits formed from c.18.1 to c. 17.0 cal. ka, and that the Bonneville flood occurred before 18 cal. ka. These ages are discordant with previous dates on shells within offshore sands, and raise questions about the validity of radiocarbon ages for shells in Lake Bonneville as well as about the age of the Bonneville flood and Provo shoreline. The timing for maximum Provo lake depths and its association with climate stages during deglaciation remain unresolved.  相似文献   

15.
High-time resolution 14C dating of Lake Baikal sediment cores indicates negative and positive anomalies of calculated linear sedimentation rate (LSR; 1.1 and 35.6 cm/ka, respectively) during the period of climate transition from the last glacial to Holocene. The timing of the Lake Baikal apparent LSR anomalies is consistent with that of the changes in the atmospheric radiocarbon concentration (Δ14C) during Younger Dryas rapid cooling event. 14C dating of lipids in the Lake Baikal surface sediments revealed that the sources of sedimentary lipids were different in each basin. In the Northern Basin of Lake Baikal, the 14C age of total lipids from the surface sediment (4.0 14C ka) was found to be older than that of TOC (1.6 14C ka). By contrast, the 14C age of total lipids in the Southern Basin was younger than that of the TOC by ca. 0.7–3.0 ka.In the Lake Hovsgol sediment cores, ages of the main lithologic boundaries during the last glacial–interglacial transition were estimated based on new 14C data sets. TOC concentration in the cores started to rapidly increase at 13.8 ± 0.3 14C ka at the base of the basinwide finely laminated layer deposited during Bølling/Allerød. The base of the layer diatomaceous mud corresponds to the end of Younger Dryas event (10.6 ± 0.1 14C ka).  相似文献   

16.
Saline, 450-m-deep Lake Van (Eastern Anatolia, Turkey) is, with 576 km3, the third largest closed lake on Earth and its largest soda lake. In 1989 and 1990, we investigated the hydrochemistry of the lake’s water column and of the tributary rivers. We also cored the Postglacial sediment column at various water depths. The sediment is varved throughout, allowing precise dating back to ca. 15 ka BP. Furthermore, lake terrace sediments provided a 606-year-long floating chronology of the Glacial high-stand of the lake dating to 21 cal. ka BP. The sediments were investigated for their general mineralogical composition, important geochemical parameters, and pore water chemistry as well. These data allow reconstructing the history of the lake level that has seen several regressions and transgressions since the high-stand at the end of the Last Glacial Maximum. Today, the lake is very alkaline, highly supersaturated with Ca-carbonate and has a salt content of about 22 g kg?1. In summer, the warmer epilimnion is diluted with river water and forms a stable surface layer. Depth of winter mixing differs from year to year but during time of investigation the lake was oxygenated down to its bottom. In general, the lake is characterized by an Na–CO3–Cl–(SO4)-chemistry that evolved from the continuous loss of calcium as carbonate and magnesium in the form of Mg-silica-rich mineral phases. The Mg cycle is closely related to that of silica which in turn is governed by the production and dissolution of diatoms as the dominant phytoplankton species in Lake Van. In addition to Ca and Mg, a mass balance approach based on the recent lake chemistry and river influx suggests a fractional loss of potassium, sodium, sulfur, and carbon in comparison to chloride in the compositional history of Lake Van. Within the last 3 ka, minor lake level changes seem to control the frequency of deep water renewal, the depth of stratification, and the redox state of the hypolimnion. Former major regressions are marked by Mg-carbonate occurrences in the otherwise Ca-carbonate dominated sediment record. Pore water data suggest that, subsequent to the major regression culminating at 10.7 ka BP, a brine layer formed in the deep basin that existed for about 7 ka. Final overturn of the lake, triggered by the last major regression starting at about 3.5 ka BP, may partly account for the relative depletion in sulfur and carbon due to rapid loss of accumulated gases. An even stronger desiccation phase is proposed for the time span between about 20 and 15 ka BP following the LGM, during which major salts could have been lost by precipitation of Na-carbonates and Na-sulfates.  相似文献   

17.
In order to reconstruct the late Pleistocene seismic stratigraphy, 550 km of high-density 3.5 kHz sub-bottom seismic-reflection profiles were recorded within a 70 km2 area in the narrow offshore border zone between Germany and Denmark. A depositional unit 3 was analysed for its seismic facies association, and in the central study area mound, oblique, channel, reflection-free, shingled, hummocky, broken and parallel associations occurred. The rims of the association shows mound, oblique, hummocky and minor parallel seismic facies. Stratigraphic control was available from 32 coring sites. In the central study area, unit 3 represents rhythmic layers of silt with fine sand and clay in an overall fining-upward 3 to 5-m-thick sequence. At the rim of the basin, the unit comprises fine sand, silt and rhythmic layers of silt with clay and fine sand. Unit 3 is proposed as having formed during the transgression of a lake, partly in contact with the Baltic Ice Lake, some time between 10.8–10.0 14C ka BP. After 10.0 14C ka BP the water body stagnated when contact with the Baltic Basin was cut off. Analysis of base level of the subunits implies tectonic activity resulting in subsidence of the central study area which could possibly have influenced the transgressive development.  相似文献   

18.
The early Holocene final drainage of glacial Lake Minong is documented by 21 OSL ages on quartz sand from parabolic dunes and littoral terraces and one radiocarbon age from a lake sediment core adjacent to mapped paleoshorelines in interior eastern Upper Michigan. We employ a simple model wherein lake-level decline exposes unvegetated littoral sediment to deflation, resulting in dune building. Dunes formed subsequent to lake-level decline prior to stabilization by vegetation and provide minimum ages for lake-level decline. Optical ages range from 10.3 to 7.7 ka; 15 ages on dunes adjacent to the lowest Lake Minong shoreline suggest final water-level decline ∼ 9.1 ka. The clustering of optical ages from vertically separated dunes on both sides of the Nadoway-Gros Cap Barrier around 8.8 ka and a basal radiocarbon date behind the barrier (8120 ± 40 14C yr BP [9.1 cal ka BP]) support the hypothesis that the barrier was breached and the final lake-level drop to the Houghton Low occurred coincident with (1) high meltwater flux into the Superior basin and (2) an abrupt, negative shift in oxygen isotope values in Lake Huron.  相似文献   

19.
Uranium-series dating of dense tufa deposited in a small cave, at former lake margins, and in large tufa mounds clarifies the timing of lake-level variation during the past 400,000 yr in the Pyramid Lake basin. A moderate-sized lake occasionally overflowed the Emerson Pass sill at elevation of 1207 m between ca. 400,000 and 170,000 and from ca. 60,000 to 20,000 yr B.P., as shown by230Th/234U ages of the cave samples,230Th-excess ages of tubular tufas, and average isochron-plot ages of shoreline-deposited tufas. (By comparison, modern Pyramid Lake is 50 m below this sill). There is a lack of tufa record during the intervening period from ca. 170,000 to 60,000 yr B.P. After ca. 20,000 yr, Pyramid Lake underwent abrupt changes in level and, based on previous14C ages, reached its highest elevation (ca 1335 m) at ca. 14,000 yr B.P. The youngest uranium-series ages are comparable with previously reported14C ages.  相似文献   

20.
In this paper we describe the stratigraphy and sediments deposited in Lake Samra that occupied the Dead Sea basin between ∼ 135 and 75 ka. This information is combined with U/Th dating of primary aragonites in order to estimate a relative lake-level curve that serves as a regional paleohydrological monitor. The lake stood at an elevation of ∼ 340 m below mean sea level (MSL) during most of the last interglacial. This level is relatively higher than the average Holocene Dead Sea (∼ 400 ± 30 m below MSL). At ∼ 120 and ∼ 85 ka, Lake Samra rose to ∼ 320 m below MSL while it dropped to levels lower than ∼ 380 m below MSL at ∼ 135 and ∼ 75 ka, reflecting arid conditions in the drainage area. Lowstands are correlated with warm intervals in the Northern Hemisphere, while minor lake rises are probably related to cold episodes during MIS 5b and MIS 5d. Similar climate relationships are documented for the last glacial highstand Lake Lisan and the lowstand Holocene Dead Sea. Yet, the dominance of detrital calcites and precipitation of travertines in the Dead Sea basin during the last interglacial interval suggest intense pluvial conditions and possible contribution of southern sources of wetness to the region.  相似文献   

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