C-14 age control of pre- and post-LGM events using N. pachyderma preserved in deep-sea sediments (Ross Sea, Antarctica)

Biogenic carbonates in Antarctic marine sequences are critical to constrain reliable chronologies for Late Quaternary glacial/interglacial events. Increased amounts of iceberg rafted debris (IBRD) in ice-proximal sediments are proxies for climate-induced disruption of the Ross Ice Shelf system. However, ice rafting events seen in deepsea sediments from this region lack of age control because they are typically barren of calcareous microfossils. We document here evidence of carbonate preservation in three out of eight cores collected from the Ross Sea continental slope (2058-3360 m-depth). AMS-C14 dates from N. pachyderma-rich IBRD range between 28.2ka and 17.2ka B.P, and between ~19 ka and 14.4 ka B.P suggesting that deep Ross Sea sediments can retain a reliable record of pre- and post- LGM events involving massive destabilization of the Ross Ice shelf-sea ice system. These events occurred at a regional scale and were possibly linked to global sea-level rise from meltwater pulse (MWP) events e.g., 19-kyr MWP.