Implications of the Wadi al-Hammeh sequences for the terminal drying of Lake Lisan, Jordan

Remnant lake and stream terraces of the Wadi el Hasa (west‐central Jordan) are associated with in situ prehistoric sites spanning > 100,000 years. Eighteen radiocarbon dates from cultural and geological deposits on the terraces facilitate the first comprehensive prehistoric landscape chronology for the southern Levant east of the Jordan Rift. In the eastern Hasa basin, the uppermost of three cut and fill surfaces (>20 m) is linked to massive fossil spring deposits and an early Middle Paleolithic occupation (100,000–70,000 B. P.), suggestive of considerably wetter climates. A later Middle Paleolithic occupation may be synchronous with the emergence of Pleistocene Lake Hasa (ca. 70,000 B. P.). Peak lake levels were attained 40,000 years ago. Dates proliferate after 25,000 B. P. and register recession of Lake Hasa (ca. 20,000 B. P.), an intervening erosional phase, and the initiation of complex humid‐desiccation cycles for the terminal Pleistocene—Holocene (17,000–9,000 B. P.). The contemporary Wadi el Hasa channel began aggrading its floodplain after 8000 B. P. and was incised to its present depths 1000–500 years ago. The prehistoric landscape history of the Hasa drainage is broadly synchronous with sequences in the Rift Valley and Negev desert and offers baseline chronologies for the Late Quaternary of eastern Jordan and the Arabian peninsula. © 1994 John Wiley & Sons, Inc.

Section: Late Quaternary Landscapes: El Hasa In Regional Perspectivementioning

confidence: 97%

Landscape and prehistoric chronology of West‐Central Jordan

Schuldenrein

Clark

1994

“…The Hasa may have been part of a more extensive regional lake complex with a series of self-contained drainage subbasins (Moumani, 1996;Hill, 2002). The upper Hasa Lake plain was infilled by Late Quaternary sediments analogous to those accumulated in the Lisan (Begin et al, 1974(Begin et al, , 1985Kaufman et al, 1992;Bartov et al, 2002) and in lake basins east of the Rift including the Hammeh Valley (Macumber and Head, 1991).…”

Section: Prehistoric Terraces and Surfacesmentioning

confidence: 97%

A Reassessment of the holocene stratigraphy of the Wadi Hasa Terrace and Hasa formation, Jordan

Schuldenrein

2007

Vita-Finzi's 1960s model for Mediterranean terrace evolution was once the basis for regional valley histories across much of the Levant. A revisit to the Hasa terrace, formerly considered Early to Middle Holocene in age, resulted in a revised chronostratigraphy. Sedimentological and geochemical analyses bolstered by radiocarbon dating indicate that valley floor construction began shortly after the end of the Middle Holocene, at least 2000 years later than initially proposed. An updated model for floodplain evolution proposes three discrete phases of accretion and alluvial plain formation. A weak cambic soil overprints the alluvium and suggests slightly moister climates than at present for much of the Late Holocene. This model is in accord with settlement data. Intensified uplands agropastoralism accelerated the erosion of slope soils that were recycled and deposited as alluvium across the valley floor. The valley floor sequences of the Hasa are analogous to alluvial chronologies for neighboring wadis of the eastern Jordan Rift and can be tied to key Middle and Late Holocene geomorphic events in the Dead Sea and the southwestern Levant. The data strongly indicate that alluvial fill histories after 1800 cal B.C. were anthropogenically driven, whereas Middle Holocene landscape changes were climatically and structurally triggered.

“…in the Azraq basin as wetter than present. During this time, lake levels and springs on the western plateau edge were supporting numerous Upper-Paleolithic habitations in the wadi systems draining into the Rift Valley including: the wadis Hasa (Schuldenrein and Clark 2001), Hisma (Henry, 1997), and Hummeh (Macumber and Head, 1991).…”

Section: Geoarchaeology: An International Journalmentioning

confidence: 99%

Quaternary paleoenvironments and potential for human exploitation of the Jordan plateau desert interior

Davies

2005

The physical, chemical, numerical, and radiometric analyses of a 31-m sediment core from the Qa'el-Jafr basin provide an important record of Quaternary paleoenvironments for the Jordan Plateau and evidence for several significant changes in climate regime. Cluster and PCA analyses of the geochemical data support the designation of major sedimentation regimes identified by stratigraphic and sediment analyses. Multiple cycles of alluvial deposition, lacustrine units, and erosional unconformities characterize the deepest sediments, followed by a period(s) of intense evaporation. Radiocarbon ages of charcoal in the uppermost 7 m place the aeolian/alluvial phase between 16,030 Ϯ 140 yr B.P. and 24,470 Ϯ 240 yr B.P. Deflation processes may explain the lack of a Holocene sequence. Despite lacking radiometric ages for the lower sediments, the thickness and degree of calcium-carbonate cementation suggest considerable age for the basal sediments, which suggests that a very long terrestrial record of Quaternary climate changes has been preserved in the Jafr basin. This new record of paleoenvironments provides important context to the archaeological record of the Jordan Plateau during the Quaternary. Several archaeological surveys demonstrate extensive human exploitation of lakes and springs of the major wadis along the western margin of the Rift Valley. However, little is known of human exploitation of the desert interiors. Qa'el-Jafr sediments demonstrate significant lacustrine and high moisture phases sufficient for human exploitation of the eastern desert during the Pleistocene.