Five-fold expansion of the Caspian Sea in the late Pliocene: New and revised magnetostratigraphic and 40Ar/39Ar age constraints on the Akchagylian Stage

作者：Sergei Lazarev, Klaudia F. Kuiper, Oriol Oms, Maia Bukhsianidze, Davit Vasilyan, Elisabeth L. Jorissen, Max J. Bouwmeester, V. Aghayeva, A.J. van Amerongen, Jordi Agustı́, David Lordkipanidze, Wout Krijgsman · 发表于：Global and Planetary Change · 年份：2021 · DOI：10.1016/j.gloplacha.2021.103624 · 被引用次数：33 · 研究领域：Marine and environmental studies、Geology and Paleoclimatology Research、Archaeology and ancient environmental studies

The Global climate reorganisation in the late Pliocene linked to enhancement of the Atlantic Ocean Thermohaline Circulation (AOTC), instigated a transition to glacial-interglacial cyclicity in the Quaternary. Enhancement of the AOTC amplified atmospheric precipitation over the Eurasian interior strengthening Northern Hemisphere Glaciation. Increased rainfall on the vast Russian Plain drained into the endorheic Caspian Sea, which makes the Caspian geological record highly potential for tracing atmospheric precipitation changes. Two major palaeohydrological events in the Caspian Sea, the Akchagylian transgression and the Akchagylian marine incursion, led to a five-fold enlargement of the Caspian Sea surface area and transformed the basin palaeoecology, enabling active interregional faunal dispersals. The Akchagylian Stage still lacks an unequivocal age model with two age constraints – the “long Akchagylian” (3.6–1.8 Ma) and the “short Akchagylian” (2.7–2.1 Ma) standing on magnetostratigraphic studies of geological records in Turkmenistan and the Kura Basin, respectively. The age discrepancies also exist within the Kura Basin, where the fossil mammal-bearing Kvabebi locality with Akchagylian marine fauna was magnetostratigraphically dated at 3.2 Ma. In this paper, we try to resolve the age contradictions for the Akchagylian Stage. We revisit the Kvabebi (Georgia) and Kushkuna (Azerbaijan) sections of the western Kura Basin and provide new magnetostratigraphic and 40Ar/39Ar age c...