Ripple cross-laminated sediments on the East Antarctic Shelf: evidence for episodic bottom water production during the Holocene?

Biosiliceous sediments sampled from a submarine valley system on the continental shelf of East Antarctica contain intervals of ripple cross-lamination interspersed with massively bedded units. Based on radiocarbon dates from one core collected on the Mac.Robertson Shelf, the most intensely cross-laminated sediments were deposited between 6 000 and 3 500 years before the present, with isolated cross-laminae deposited at other times in the Holocene.

从东南极大陆架海底谷系采集的生物硅质沉积物，其层序中夹有发育波纹交错层理的层段与块状层理地层单元。基于麦克·罗伯逊陆架（Mac.Robertson Shelf）上采集的单根岩芯的放射性碳定年结果，交错层理最为发育的沉积物沉积于距今6000至3500年之间，而孤立的交错层理则形成于全新世（Holocene）的其他时段。