6 research outputs found
Late pleistocene sedimentation history of the Shirshov Ridge, Bering Sea
The analysis of the lithology, grain-size distribution, clay minerals, and geochemistry of Upper
Pleistocene sediments from the submarine Shirshov Ridge (Bering Sea) showed that the main source area was
the YukonâTanana terrane of Central Alaska. The sedimentary materials were transported by the Yukon
River through Beringia up to the shelf break, where they were entrained by a strong northwestward-flowing
sea current. The lithological data revealed several pulses of ice-rafted debris deposition, roughly synchronous
with Heinrich events, and periods of weaker bottom-current intensity. Based on the geochemical results, we
distinguished intervals of an increase in paleoproductivity and extension of the oxygen minimum zone. The
results suggest that there were three stages of deposition driven by glacioeustatic sea-level fluctuations and
glacial cycles in Alaska