Pleistocene Ice-Rafted Pebble Abundance, Eastern North Atlantic Ocean: ABSTRACT

Abstract

Detailed examination of a suite of 8 deep-sea cores collected by USNS Kane, north of 48°N lat., in the eastern North Atlantic Ocean indicates an unusually high abundance of coarser than sand-size rafted debris. An average of 3 pebbles per core, each weighing greater than 8 g, characterizes the suite. In fact, the average weight for all pebbles found was 30 g. Assuming that these averages are compatible for the rest of the eastern North Atlantic, and assuming an average age of 300,000 years for the 8 cores, it has been calculated that over 2.6 × 1013 metric tons of coarse debris has been transported from Europe, Iceland, and the Faeroe Islands by ice-rafting since late middle Pleistocene time. If coarse debris represents a total of only 20% of all ice- afted sediment, then in the eastern North Atlantic, over 1.3 × 1014 metric tons of sediment has been ice-rafted in the last 300,000 years. End_of_Article - Last_Page 640------------