Fossil-Based Reconstructions of Ancient Water Bodies in the Levantine Deserts

Mischke, Steffen; Ginat, Hanan; Al-Saqarat, Bety S.; Faershtein, Galina; Porat, Naomi; Rech, Johanna; Enzel, Yehouda; Bar‐Yosef, Ofer

doi:10.1017/9781316106754.045

Cited by 4 publications

(13 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The lower and upper parts of the Gharandal sequence were not dated. Moreover, given that the OSL and 14 C ages are stratigraphically inconsistent (Braun, 2015;Mischke et al, 2017;Ginat et al, 2017), and 14 C ages draw close to the limit of the method, there is a need for a better chronology for this site, especially in the context of the lithic artefacts observed within the stratified sediments by Henry et al (2001).…”

Section: Wadi Gharandal a Riverine Oasis In Southern Jordanmentioning

confidence: 99%

A wetland oasis at Wadi Gharandal spanning 125–70 ka on the human migration trail in southern Jordan

et al. 2020

View full text Add to dashboard Cite

Former lakes and wetlands can provide valuable insights to the late Pleistocene environments encountered by the first humans to enter the Levant from Africa. Fluvial incision along Wadi Gharandal in hyperarid southern Jordan has exposed remnants of a small riverine wetland that accumulated as a sedimentary sequence up to ~20 m thick. We conducted a chronometric and sedimentological study of this wetland, including 10 optically stimulated luminescence dates. The wetland sequence accumulated during the period ~125 to 70 ka in response to a positive water balance coupled with a (possibly coseismic) landslide that dammed the outlet. The valley fill was dissected when the dam was incised shortly after ~36 ± 3 ka. Comparison of our ages with regional palaeoclimate indicates that the Gharandal oasis developed during the relatively humid Marine Isotope Stage 5. A minimum age of 74 ± 7 ka for two Levallois flakes collected from stratified sediments suggests that the oasis was visited by humans during the critical 130–90 ka time window of human migration out of Africa. Gharandal joins a growing network of freshwater sites that enabled humans to cross areas of the Levant and Arabia along corridors of human dispersal.

show abstract

Section: Wadi Gharandal a Riverine Oasis In Southern Jordanmentioning

confidence: 99%

A wetland oasis at Wadi Gharandal spanning 125–70 ka on the human migration trail in southern Jordan

et al. 2020

View full text Add to dashboard Cite

show abstract

“…By contrast, evaporites commonly develop in waning stages of closed-basin lakes. Detailed analysis of the microfauna will often assist in the distinction between lake versus GWDs (e.g., Mischke et al, 2017).…”

Section: Megalakes In the Sahara? 257mentioning

confidence: 99%

Megalakes in the Sahara? A Review

et al. 2018

View full text Add to dashboard Cite

The Sahara was wetter and greener during multiple interglacial periods of the Quaternary, when some have suggested it featured very large (mega) lakes, ranging in surface area from 30,000 to 350,000 km2. In this paper, we review the physical and biological evidence for these large lakes, especially during the African Humid Period (AHP) 11–5 ka. Megalake systems from around the world provide a checklist of diagnostic features, such as multiple well-defined shoreline benches, wave-rounded beach gravels where coarse material is present, landscape smoothing by lacustrine sediment, large-scale deltaic deposits, and in places, tufas encrusting shorelines. Our survey reveals no clear evidence of these features in the Sahara, except in the Chad basin. Hydrologic modeling of the proposed megalakes requires mean annual rainfall ≥1.2 m/yr and a northward displacement of tropical rainfall belts by ≥1000 km. Such a profound displacement is not supported by other paleo-climate proxies and comprehensive climate models, challenging the existence of megalakes in the Sahara. Rather than megalakes, isolated wetlands and small lakes are more consistent with the Sahelo-Sudanian paleoenvironment that prevailed in the Sahara during the AHP. A pale-green and discontinuously wet Sahara is the likelier context for human migrations out of Africa during the late Quaternary.

show abstract

“…The authors inferred the lake to have existed during the last glacial period based on archaeological materials and one 14 C age of 25,000 14 C yr on bulk carbonate (Huckriede and Wiesemann, 1968). Subsequent work, however, has demonstrated that these deposits are wetland and not lake deposits, and that the deposits are >40,000 yr old (Enzel et al, 2008; Mischke et al, 2015, 2017; Rech et al, 2017). Although the deposits indicate more pluvial conditions existed in the past, the unknown age of the deposits limits their significance as a paleoclimatic proxy.…”

Section: Discussionmentioning

confidence: 99%

“…Unit C deposits represent greater groundwater discharge and wetter climatic conditions at this time (Winer, 2010; Rech et al, 2017). Wetland deposits have also been identified in Wadi Gharandal, where a radiocarbon and an OSL age indicate that water tables there were elevated at ~32 ka, but the duration of wetland formation at this locality is not well constrained (Mischke et al, 2017).…”

Section: Discussionmentioning

confidence: 99%

Activation of a small ephemeral lake in southern Jordan during the last full glacial period and its paleoclimatic implications

Catlett

Rech

Pigati³

et al. 2017

Quat. res.

Self Cite

View full text Add to dashboard Cite

Playas, or ephemeral lakes, are one of the most common depositional environments in arid and semiarid lands worldwide. Playa deposits, however, have mostly been avoided as paleoclimatic archives because they typically contain exceptionally low concentrations of organic material, making14C dating difficult. Here, we describe a technique for concentrating organic matter in sediments for radiocarbon dating and apply it to playa sediments recovered from a 2.35 m sediment core from a small playa in southern Jordan. Based on14C ages of the organic concentrate fraction, the playa was active from ~29 to 21 ka, coincident with the last major high stand of Paleolake Lisan and wet conditions recorded by other paleoclimatic proxies in the southernmost Levant during the last full glacial period (35–20 ka). The timing and spatial pattern of these records suggests that the increased moisture was likely derived from more frequent and deeper eastern Mediterranean (EM) cyclones associated with the intensification of the westerlies. The presence of full glacial pluvial deposits in southern Jordan (29°N), and the lack of similarly aged deposits in the northern Arabian Peninsula to the south, suggests that the southerly limit of the incursion of EM cyclones during last full glacial period was ~28°N.

show abstract

Fossil-Based Reconstructions of Ancient Water Bodies in the Levantine Deserts

Cited by 4 publications

References 0 publications

A wetland oasis at Wadi Gharandal spanning 125–70 ka on the human migration trail in southern Jordan

A wetland oasis at Wadi Gharandal spanning 125–70 ka on the human migration trail in southern Jordan

Megalakes in the Sahara? A Review

Activation of a small ephemeral lake in southern Jordan during the last full glacial period and its paleoclimatic implications

Contact Info

Product

Resources

About