Humid phases on the southwestern Arabian Peninsula are consistent with the last two interglacials

Stone, A., Inglis, R. H., Candy, I., Sahy, D., Jourdan, A.-L., Barfod, D. N. and Alsharekh, A. M. (2023) Humid phases on the southwestern Arabian Peninsula are consistent with the last two interglacials. Quaternary Science Reviews, 319, 108333. (doi: 10.1016/j.quascirev.2023.108333)

Abstract

Past environmental and climatic conditions within the Arabian Peninsula are key to understanding the setting for hominin dispersal across the Saharo-Arabian dryland belt. The tufa deposits within the volcanic harrats on the southwest coast of Saudi Arabia fill a significant spatial gap in the distribution of palaeoenvironmental records on the west coast of the Arabian Peninsula adjacent to the Red Sea. In the catchment of Wadi Dabsa in the Harrat Al Birk, there are widespread fossil palustrine to shallow-lacustrine tufa deposits with fluvial elements. Several phases of tufa accumulation, separated by fluvial downcutting, are observable within these powerful palaeoenvironmental proxies. U–Th dating of targeted dense, banded tufa facies, yield ages that are stratigraphically consistent at the landscape scale, and indicate that tufa accumulation occurred during distinct humid phases broadly coeval with the last two warm interglacial Marine Isotope Stages (MIS 7 and MIS 5). For the first time this shows humid intervals in southwest Arabia coincident with the southern coast. There is a simlar pattern emerging further north in the Arabian Peninsula, The Sinai and Levant and further on into continental Europe. Furthermore, tufa δ18O ranges from −14.6 to −1.9‰, covering a range similar to those reported for tufa from north African oasis sites and speleothems elsewhere on the Arabian Peninsula and The Levant. The lowest δ18O values are derived from MIS 5e samples, a pattern in agreement with speleothems in Yemen and Oman, and consistent with an isotopic-enabled climate model simulation for this time slice. The δ13C and Sr isotopic compositions of dated tufa samples indicate deposition from shallow-circulating meteoric water, with no geothermal influence. This, along with the δ18O values, suggest a freshwater supply that was a potable water source in this landscape. The δ13C signatures at Wadi Dabsa are more negative than for parts of north Africa, suggesting Wadi Dabsa may have experienced comparatively higher biomass, thicker soils and wetter conditions with lower evaporative losses. This new record of tufa deposition during the middle and late Pleistocene, suggests for the first time that the west coast of Arabia experienced a similar history of humid phases over the past 250 ka as southern Arabia and the Nefud in the northern interior. These regional changes in hydroclimatic regime occur at timescales coincident with hominin dispersals.

• Item Type: Articles
• Additional Information: A.M.A. acknowledges the support of the Researchers Supporting Project number (RSP-2022/126), King Saud University, Riyadh, Saudi Arabia. Work at Wadi Dabsa was carried out within the SURFACE project funded by the EU's Horizon 2020 research and innovation program under Marie Skłodowska-Curie Actions (Grant No. 660343), “Human-Landscape- Interactions and Global Dispersals: The SURFACE Record of Paleolithic Arabia”. For fieldwork funding we thank: The Gerald Avery Wainwright Fund for Near Eastern Archaeology at the University of Oxford (2015, 2017); the British Academy, Albert Reckitt Fund (2017); the British Foundation for the Study of Arabia (International Association for the Study for Arabia) (2017); and the Department of Archaeology Research Fund, University of York (2015). Funding for U–Th dating was provided by the NERC isotopes Geosciences Facilities (IP-1739-0517). Funding for isotopic analysis was provided by the British Foundation for the Study of Arabia (International Association for the Study for Arabia) (2019) under grant “Stable isotopic signatures from tufa carbonates: Providing environmental context for Palaeolithic archaeology and palaeorainfall composition data to validate climate models.” and subsampling was undertaken by A.S. at Centre for Quaternary Research, Department of Geography at Royal Holloway, University of London.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Barfod, Dr Dan
• Authors: Stone, A., Inglis, R. H., Candy, I., Sahy, D., Jourdan, A.-L., Barfod, D. N., and Alsharekh, A. M.
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Quaternary Science Reviews
• Publisher: Elsevier
• ISSN: 0277-3791
• ISSN (Online): 1873-457X
• Published Online: 29 September 2023
• Copyright Holders: Copyright © 2023 The Authors.
• First Published: First published in Quaternary Science Reviews 319:108333
• Publisher Policy: Reproduced under a Creative Commons license