GSA Connects 2023 Meeting in Pittsburgh, Pennsylvania

Paper No. 158-6
Presentation Time: 9:45 AM

WET PHASES IN THE LEVANT CORRIDOR DURING THE LATE PLEISTOCENE: INSIGHTS FROM A MULTI-PROXY STUDY OF LAKE SEDIMENTS FROM NORTHERN ISRAEL


WALDMANN, Nicolas1, YASSINE, Abdel-Aziz Abdrahamane1, PARTH, Shah1, WEINSTEIN-EVRON, Mina2 and MAZZINI, Ilaria, PhD3, (1)Dr. Moses Strauss Department of Marine Geosciences, University of Haifa, Haifa, 3498838, Israel, (2)Zinman Institute of Archaeology, University of Haifa, Haifa, 3498838, Israel, (3)Institute of Environmental Geology and Geoengineering, Rome, 00015, Italy

The Levant is an environmentally sensitive region that had faithfully responded to any small-scale hydro-climate variability in the geological past. Moreover, in recent years it has been in the focus of concern because of recurring draughts and temperature extremes, which, in turn, might have played a key role in local geopolitical instabilities. Terrestrial archives from this region can thus serve as valuable recorders of climate variability and its forcing factors, as well as to disentangle the impact on the ecology and environment. A multi-proxy approach is applied to a >160 m long sedimentary record from Lake Hula, northern Israel to identify the possible impact of precipitation and temperature changes on the hydrological system during the Late Pleistocene. The measurements include sedimentology (grain size), geochemistry (elemental content, mineralogy, total organic matter content, isotopes), and biological proxies (ostracods), in order to reconstruct the processes occurring within both the limnic environment and allogenic processes. Initial investigation of the lithology and elemental ratio concentrations shows alternating intervals that appear to be associated with lower runoff from the lake catchment (identified as a decrease in allogenic minerals and increase in authigenic components), intercalating with intervals characterized by higher runoff. This initial interpretation implies intercalation between dry and wet climate conditions. Furthermore, variations in the sediment lithology and geochemical proxies suggest fluctuations related to the dominating precipitation regime (winter rains from the Mediterranean), thus proposing that a millennial-scale orbital forcing variability could potentially be disentangled out from the record. In parallel, isotopic analyses (δ18O and δ13C) of ostracod shells can help estimating water temperatures and lake level changes, which can be associated with precipitation intensity changes over the region. Moreover, by reconstructing the behavior of the lake system in regard to hydro-climate variability through time, one can better comprehend the current impact of anthropogenic stress and assess future trends. Overall, this study provides a comprehensive picture of the different mechanisms driving abrupt climate changes in the region and explores their potential relevance to future climatic studies.