Fluvial environmental contexts for archaeological sites in the Upper Khabur basin (northeastern Syria)

Abstract

Today the eastern tributaries of the Upper Khabur run dry during the summer and the landscape is devoid of trees. This picture is misleading when we try to understand archaeological sites within their former environmental context. Interdisciplinary geomorphological, archaeobotanical and ostracod research on a sequence from the Wadi Jaghjagh indicates that relatively stable, perennial flow velocities occurred during the mid 4th to mid-3rd millennium BC. Evidence was found for a gallery forest and swamp belt along the Jaghjagh during the mid-4th millennium BC. Oak park woodland was present within the region in the 3rd millennium BC and probably up to at least the 3rd century AD. Shortly after 2500 BC, Jaghjagh stream velocities probably decreased or the stream bed had changed its location. Later deposits, possibly dating to the 5th century BC, indicate similar, rather stable flow of the Jaghjagh. More recently however, about ca. AD 900 or afterwards, a flashflood-like regime occurred, which may relate to deforestation. The Wadi Khanzir sediment archives reflect the flashy intermittent regime of this stream, like it still is today, with flashflood evidence dating to the first half of the Holocene and probably dating to approximately AD 400 or later. Along the Jarrah, topsoil was eroded and redeposited by the wadi sometime between 1300 and 600 BC. This may have been caused by the intensive resettlement program of this region around 800 BC. Between about 600 and 300 BC 1.5 m of clay was deposited on the plain.

Contextualizing Early Urbanization: Settlement Cores, Early States and Agro-pastoral Strategies in the Fertile Crescent During the Fourth and Third Millennia BC

“…These semi-arid plains are dissected by smaller valleys, some of which, such as the Jaghjagh near Brak, during the mid fourth millennium BC, were remarkably verdant with a rich riverine vegetation of Populus (poplar) and Salix (willow), alongside slow flowing cool waters (Riehl 2011, p. 104). Although alluviation is limited across much of their extent, the flood plains themselves show significant but varying degrees of sedimentation, resulting in localized burial of settlements (Kuzucuoglu et al 2004;Casana and Wilkinson 2005;Deckers 2011;Deckers and Riehl 2007).…”

Regional power and local ecologies: Accumulated population trends and human impacts in the northern Fertile Crescent

“…However, as a result of over-extraction for modern irrigation the river was essentially dry during the summers by the 1990s and 2000s when the alluvial sequence was investigated. During the 5th and 4th millennia BC the channel fill of well-bedded sand and gravel containing micro-fossils indicates a fairly steady flow, with additional inflow from springs (Riehl 2011;Deckers and Riehl, 2007). Bed deposits were diachronous, with flowing water deposits being especially evident in the 5th and 4th millennium and continuing into the first millennium BC both to the north near Tell Hamidi (Deckers 2011: 88-92) and to the south at Tell Ma'az, Tell Barri and al-Amal (Figs.…”

“…Upstream and within other tributaries, OSL, thermoluminescence (TL) screening, and radiocarbon dating of sediments and carbonized material from the Wadis Jaghjagh, Khanzir and Jarrah provide age estimates on this upper clay fill in the region of 2600+400 BP (OSL), 2600+800 BP (TL screening), 2300+200 BP (OSL) and 2,200+900 (TL screening) (Deckers and Riehl, 2007). In addition, around AD 244 (1780 + 30 BP), fragments of oak charcoal in clayey sand in the Wadi Jaghjagh (Deckers and Riehl, 2007) suggest that there was localized woodland destruction during the Roman/Parthian period.…”

“…In addition, around AD 244 (1780 + 30 BP), fragments of oak charcoal in clayey sand in the Wadi Jaghjagh (Deckers and Riehl, 2007) suggest that there was localized woodland destruction during the Roman/Parthian period. Despite the broad standard deviations, the above dates for the upper fill support the artefactual and stratigraphic data from near Tell Brak for a later low-energy upper fill of Iron Age and later date.…”

Paleohydrological implications of late Quaternary fluvial deposits in and around archaeological sites in Syria

“…Such data provide only indirect information about fluvial processes. Some studies investigated Holocene fluvial deposits along rivers and wadis in the Levant (e.g., Butzer, 1980;Wilkinson, 1999;Deckers and Riehl, 2007) because younger deposits exposed along the riverside can be studied relatively easily. The number of studies on fluvial deposits, however, remains limited in the Levant, especially in some countries, including Syria.…”