Freshwater ostracodes in Quaternary Permafrost deposits from the Siberian Arctic

• Main Authors: Wetterich, Sebastian, Schirrmeister, Lutz
• Format: Conference Object
• Language: unknown
• Published: 2005
• Subjects: Arctic; Laptev Sea; Ice; laptev; permafrost; wedge*
• Online Access: https://epic.awi.de/id/eprint/12895/; https://hdl.handle.net/10013/epic.23300

Ostracode analysis was carried out on samples from ice-rich permafrost deposits obtained on the BykovskyPeninsula (Laptev Sea). A composite profile was investigated that covers most of a 38 m thick permafrost sequence and corresponds to the last ca. 60 kyr of the Late Quaternary. The ostracode assemblages are similar to those known from European Quaternary lake deposits during cold stages. The ostracode habitatswere small, shallow, cold, oligotrophic pools located in low-centred ice-wedge polygons or in smallthermokarst depressions. In total, fifteen taxa, representing seven genera, were identified from 65 samples.The studied section is subdivided into six ostracode zones that correspond to Late Quaternary climatic and environmental stadial-interstadial variations established by other paleoenvironmental proxies: (1) cold anddry Zyrianian stadial (58 to 53 kyr BP); (2) warm and dry Karginian interstadial (48 to 34 kyr BP); (3) transitionfrom the Karginian interstadial to the cold and dry Sartanian stadial (34 to 21 kyr BP); (4) transitionfrom the Sartanian stadial to the warm and dry Late Pleistocene period, the Allerød (21 to 14 kyr BP); (5)transition from the Allerød to the warm and wet Middle Holocene (14 to 7 kyr BP); and (6) cool and wet Late Holocene (ca. 3 kyr BP). The abundance and diversity of the ostracodes will be used as an additional bioindicator for paleoenvironmental reconstructions of the Siberian Arctic