Glacial history and palaeo-environmental change of southern Taimyr Peninsula, Arctic Russia, during the Middle and Late Pleistocene

Abstract

This Data in Brief paper contains data (including images) from Quaternary sedimentary successions investigated along the Bol'shaya Balakhnya River and the LuktakheUpper TaimyraeLogata river system on southern Taimyr Peninsula, NW Siberia (Russia). Marine foraminifera and mollusc fauna composition, extracted from sediment samples, is presented. The chronology (time of deposition) of the sediment successions is reconstructed from three dating methods; (i) radiocarbon dating of organic detritus (from lacustrine/fluvial sediment) and molluscs (marine sediment) as finite ages (usually <42 000 years) or as non-finite ages (>42 000e48 000 years) on samples/sediments beyond the radiocarbon

Unveiling the Ecological Applications of Ancient DNA From Mollusk Shells

“…The above-lying unit B fluvial sediments were dated to their deposition by Optically Stimulated Luminescence to 42-43 kyr (± 3-4 kyr), which is within the Middle Zyryanka (MIS 3), while redeposited mollusks (P. arctica) within the unit B sediments, eroded from underlying marine unit A, gave ESR ages of 122 and 123 kyr (± 15 kyr). Möller et al, 2019b thus concluded that the unit A marine sediment can be placed with high confidence to their deposition within the Karginsky interglacial (MIS 5e), equivalent to the North West European Eemian. Site BBR 17 is located ∼50 km from the ocean today, but paleoenvironmental reconstructions showed marine inundation of the Taimyr lowlands in front of the retreating ice margin at the transition between the Taz glaciation (MIS 6) and into the Karginsky interglacial (MIS 5e), with sea level at its maximum reaching levels in excess of 80 m above present sea level in this area (Möller et al, 2019b).…”

“…Möller et al, 2019b thus concluded that the unit A marine sediment can be placed with high confidence to their deposition within the Karginsky interglacial (MIS 5e), equivalent to the North West European Eemian. Site BBR 17 is located ∼50 km from the ocean today, but paleoenvironmental reconstructions showed marine inundation of the Taimyr lowlands in front of the retreating ice margin at the transition between the Taz glaciation (MIS 6) and into the Karginsky interglacial (MIS 5e), with sea level at its maximum reaching levels in excess of 80 m above present sea level in this area (Möller et al, 2019b). The shells subjected to aDNA analyses were sampled from frozen marine unit A sediment (permafrost) at site BBR 17A and have been kept frozen since the time of collection in 2010 to optimize DNA preservation post-excavation.…”

“…For aDNA analyses, we selected three fossils identified as mollusk shells, sampled in a river-cut sediment succession along the lower reaches of the Bol'shaya Balaknya River (site BBR17 in Möller et al, 2019b, with close-by subsites 17A and 17B), situated in the southern portion of the Taimyr Peninsula, Russian Federation (N73 • 37,084 ; E105 • 38,178 ; Supplementary Table S1). This location is south of the limits of repeated Kara Seabased glaciations during the last glacial cycle (the Zyryanka, Marine Isotope Stage (MIS) 5d-2) (Svendsen et al, 2004;Möller et al, 2015Möller et al, , 2019b. The samples were all found in a distinct marine silty clay designated sediment unit A, overlaid by fluvial sand and gravel (sediment unit B) (see sediment log in Möller et al, 2019b).…”

“…This location is south of the limits of repeated Kara Seabased glaciations during the last glacial cycle (the Zyryanka, Marine Isotope Stage (MIS) 5d-2) (Svendsen et al, 2004;Möller et al, 2015Möller et al, , 2019b. The samples were all found in a distinct marine silty clay designated sediment unit A, overlaid by fluvial sand and gravel (sediment unit B) (see sediment log in Möller et al, 2019b). The marine unit A sediment is rich in bivalve and gastropod shells ( Supplementary Table S2), including subarctic species such as Buccinum undatum, Mytilus edulis, and Macoma balthica, not present today in the Kara Sea (to the north) and the Laptev Sea (to the east), thus suggesting interglacial conditions at sediment deposition (Möller et al, 2019b).…”

“…The samples were all found in a distinct marine silty clay designated sediment unit A, overlaid by fluvial sand and gravel (sediment unit B) (see sediment log in Möller et al, 2019b). The marine unit A sediment is rich in bivalve and gastropod shells ( Supplementary Table S2), including subarctic species such as Buccinum undatum, Mytilus edulis, and Macoma balthica, not present today in the Kara Sea (to the north) and the Laptev Sea (to the east), thus suggesting interglacial conditions at sediment deposition (Möller et al, 2019b). Three shells (Portlandia arctica) from the unit A sediments were dated by Electron-Spin Resonance (ESR) to 101-105 kyr (± 9-12 kyr; averaged here to ≥100 kyr).…”