Active sand seas and the formation of desert loess

Crouvi, Onn; Amit, Rivka; Enzel, Yehouda; Gillespie, Alan R.

doi:10.1016/j.quascirev.2010.04.026

Cited by 163 publications

(103 citation statements)

References 106 publications

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“…19). Thus, our feldspar and calcite results support the hypothesis of Crouvi et al (2008Crouvi et al ( , 2010Crouvi et al ( , 2012, Enzel et al (2008Enzel et al ( , 2010, and Amit et al (2011) that the SinaieNegev erg could be at least a partial source for loess in Israel. It is important to point out, however, that loess in Israel, at least in places, contains significant amounts of very fine-grained particles that are unlikely to be produced by abrasion in the SinaieNegev erg.…”

Section: Implications For the Origin Of Loess From Aeolian Sand In Thsupporting

confidence: 84%

“…1). Crouvi et al (2008Crouvi et al ( , 2010Crouvi et al ( , 2012, Enzel et al (2008Enzel et al ( , 2010, and Amit et al (2011) have emphasized the importance of this dunefield in supplying silt-sized quartz, generated by aeolian abrasion of sand-sized quartz, to loess downwind. If reduction of sand-sized quartz to silt size by aeolian abrasion has occurred, then other minerals in the SinaieNegev erg should also be affected by this process.…”

Section: Introductionmentioning

confidence: 99%

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Origin of the Sinai–Negev erg, Egypt and Israel: mineralogical and geochemical evidence for the importance of the Nile and sea level history

Muhs

Roskin

Tsoar

et al. 2013

Quaternary Science Reviews

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"Origin of the Sinai-Negev erg, Egypt and Israel: mineralogical and geochemical evidence for the importance of the Nile and sea level history" (2013 Overall, the mineralogical data suggest that the dunes are derived dominantly from the Nile Delta, with Sinai wadi sands being a minor contributor. Geochemical data that proxy for both the light mineral fraction (SiO 2 /10eAl 2 O 3 þ Na 2 O þ K 2 OeCaO) and heavy mineral fraction (Fe 2 O 3 eMgOeTiO 2 ) also indicate a dominant Nile Delta source for the dunes. Thus, we report here the first empirical evidence that the SinaieNegev dunes are derived dominantly from the Nile Delta. Linkage of the SinaieNegev erg to the Nile Delta as a source is consistent with the distribution of OSL ages of Negev dunes in recent studies. Stratigraphic studies show that during the Last Glacial period, when dune incursions in the SinaieNegev erg began, what is now the Nile Delta area was characterized by a broad, sandy, minimally vegetated plain, with seasonally dry anastomosing channels. Such conditions were ideal for providing a ready source of sand for aeolian transport under what were probably much stronger glacial-age winds.With the post-glacial rise in sea level, the Nile River began to aggrade. Post-glacial sedimentation has been dominated by fine-grained silts and clays. Thus, sea level, along with favorable climatic conditions, emerges as a major influence on the timing of dune activity in the SinaieNegev erg, through its control on the supply of sand from the Nile Delta. The mineralogy of the SinaieNegev dunes is also consistent with a proposed hypothesis that these sediments are an important source of loess in Israel.Published by Elsevier Ltd.

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Section: Implications For the Origin Of Loess From Aeolian Sand In Thsupporting

confidence: 84%

Section: Introductionmentioning

confidence: 99%

Origin of the Sinai–Negev erg, Egypt and Israel: mineralogical and geochemical evidence for the importance of the Nile and sea level history

Muhs

Roskin

Tsoar

et al. 2013

Quaternary Science Reviews

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“…The sediments accumulated during the Late Pleistocene period when desert storms brought sands from the northern Sinai Desert to the area (Yaalon and Dan, 1974;Crouvi et al, 2010). Since the distance from the parent material to the accumulation site is relatively short, these wind-blown sediments maintained a fairly coarse-grain composition, contrary to the classic silt-size loess sediments (Crouvi et al, 2010). Nevertheless, the grain size distribution in the loessial sediments is highly variable and depends on the wind speed (Crouvi et al, 2010).…”

Section: Study Areamentioning

confidence: 99%

Infiltration in layered loessial deposits: Revised numerical simulations and recharge assessment

Dafny

Šimůnek

2016

Journal of Hydrology

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s u m m a r yThe objective of this study is to assess recharge rates and their timing under layered loessial deposits at the edge of arid zones. Particularly, this study is focused on the case of the coastal plain of Israel and Gaza. First, results of a large-scale field infiltration test were used to calibrate the van Genuchten parameters of hydraulic properties of the loessial sediments using HYDRUS (2D/3D). Second, optimized soil hydraulic parameters were used by HYDRUS-1D to simulate the water balance of the sandy-loess sediments during a 25-year period for three environmental conditions: bare soil, and soil with both sparse and dense natural vegetation.The best inverse parameter optimization run fitted the infiltration test data with the RMSE of 0.27 d (with respect to a moisture front arrival) and R 2 of 96%. The calibrated model indicates that hydraulic conductivities of the two soil horizons, namely sandy loam and sandy clay loam, are 81 cm/d and 17.5 cm/d, respectively. These values are significantly lower than those previously reported, based on numerical simulations, for the same site. HYDRUS-1D simulation of natural recharge under bare soil resulted in recharge estimates (to the aquifer) in the range of 21-93 mm/yr, with an average recharge of 63 mm/yr. Annual precipitation in the same period varied between 100 and 300 mm/yr, with an average of 185 mm/yr. For semi-stabilized dunes, with 26% of the soil surface covered by local shrub (Artemisia monosperma), the mean annual recharge was 28 mm. For the stabilized landscape, with as much as 50% vegetation coverage, it was only 2-3 mm/yr. In other words, loessial sediments can either be a source of significant recharge, or of no recharge at all, depending on the degree of vegetative cover. Additionally, the time lag between specific rainy seasons and corresponding recharge events at a depth of 22 m, increased from 2.5 to 5 years, and to about 20 years, respectively, with an increasing vegetative cover. For this reason, and also likely due to a great depth of loessial sediments, no correlation was found between annual recharge and annual precipitations of the same year or subsequent years. Similarly, no differences were found between summer and winter recharge fluxes. Instead, numerical simulations indicated continuous year-round recharge of the aquifer. We conclude that the layered subsurface acts as a short-term (annual) and long-term (multi-annual) buffer to smooth sudden precipitation/infiltration events. Vegetation conditions can help in predicting long-term recharge rates (as percentage of annual precipitation), which in turn need to be considered when assigning recharge characteristics in regional assessments and models.

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“…The silty texture and the high accretion rate of the floodplain are thought to reflect intense redistribution by the Wadi of loess material provided by the coastal sand desert. Other more distant sources of loess such as the Rub' al Khali desert in the Arabian Peninsula (Crouvi et al, 2010) or East Africa (Middleton and Goudie, 2001) are also possibly involved. Coarsergrained lenses are locally intercalated in the sequence and correspond to secondary channels or crevasse splay deposits.…”

Section: Environmental Context 55000 Years Agomentioning

confidence: 99%

Cultural and human dynamics in southern Arabia at the end of the Middle Paleolithic

Delagnes

Crassard

Bertrán

et al. 2013

Quaternary International

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a b s t r a c tThe Arabian Peninsula has long been considered as a region devoid of long-term human settlement until the Holocene period, as a result of drastic climatic changes throughout the Pleistocene. It might be expected that the area was deserted during hyper-arid and arid periods, and populated by new migrant groups during humid events, according to a "push and pull" phenomenon. Although this scenario may be perfectly valid for a large part of the Peninsula, a set of recent data points to the persistence of populations in several regions, which may have served as refugia for human groups who developed their own technological traditions. Such a scenario is suggested by:(1) The succession of dense human occupations under arid conditions between ca. 60 and 50 ka, in the Wadi Surdud basin, a small sedimentary basin in the foothills of the Yemeni Western Highlands. This archaeological site complex encompasses several successive human settlements characterized by a Middle Paleolithic tradition which significantly differs from the Middle Paleolithic and Middle Stone Age contemporaneous traditions from neighboring regions; (2) The regional diversity of the Middle Paleolithic throughout the Saharo-Arabian arid belt during MIS 3, expressed by an array of local techno-typological facies that likely relate to distant and disconnected source regions where populations contracted when climate worsened.Together with a set of high-resolution archaeological contexts recently discovered in the Arabian Peninsula and dated to MIS 5, these data suggest that the major human expansion waves which occurred in the region during the Upper Pleistocene are correlated with the wet phases of MIS 5, while populations probably contracted into a few refugia areas at the beginning of MIS 3.

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Active sand seas and the formation of desert loess

Cited by 163 publications

References 106 publications

Origin of the Sinai–Negev erg, Egypt and Israel: mineralogical and geochemical evidence for the importance of the Nile and sea level history

Origin of the Sinai–Negev erg, Egypt and Israel: mineralogical and geochemical evidence for the importance of the Nile and sea level history

Infiltration in layered loessial deposits: Revised numerical simulations and recharge assessment

Cultural and human dynamics in southern Arabia at the end of the Middle Paleolithic

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