Abstract

Fifty-three pebbles and small cobbles, and several pieces of asphalt, were dredged from the deep Pacific Ocean 60 nautical miles southwest of Cedros Island, Baja California, at a depth of about 2100 fathoms. Thirteen of the rocks are igneous, 12 are metamorphic, and 28 are sedimentary. More than half of the pieces are rounded or sub-rounded. Eighteen sedimentary pieces contain holes or portions of holes due to the activities of boring animals such as pholads. An analysis of the asphalt failed to indicate if it is of natural origin or a refined product. The varied lithology, the rounding of a large number of pieces, and the pholad-type borings indicate that the rocks have been transported from a shallow-water environment to the deep sea. Several transporting mechanisms are discussed. Rafting of the rocks by floating kelp is the most likely means of transport.

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