Acoustic facies on the inner Kara Sea Shelf: implications for late Weichselian to Holocene sediment dynamics

• Published in: Marine Geology
• Main Author: Dittmers, Klaus
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: ELSEVIER SCIENCE BV 2008
• Subjects: Kara Sea
• Online Access: https://epic.awi.de/id/eprint/14633/; https://doi.org/10.1016/j.margeo.2008.06.004; https://hdl.handle.net/10013/epic.39240

We studied the impact of the last glacial (late Weichselian) sea level cycle on sediment architecture in theinner Kara Sea using high-resolution acoustic sub-bottom profiling. The acoustic lines were ground-truthedwith dated sediment cores. Furthermore we refined the location of the eastern LGM ice margin, by new subbottom profiles. New model results of post-Last Glacial Maximum (LGM) isostatic rebound for this area allowa well-constrained interpretation of acoustic units in terms of sequence stratigraphy. The lowstand (orregressive) system tract sediments are absent but are represented by an unconformity atop of Pleistocenesediments on the shelf and by a major incised dendritic paleo-river network. The subsequent transgressiveand highstand system tracts are best preserved in the incised channels and the recent estuaries while onlyminor sediment accumulation on the adjacent shelf areas is documented. The Kara Sea can be subdividedinto three areas: estuaries (A), the shelf (B) and (C) deeper lying areas that accumulated a total of 114 x1010 t of Holocene sediments.