Delaware river: evidence for its former extension to wilmington submarine canyon.

Seismic-reflection profiles indicate that during the Pleistocene the Delaware River flowed across the continental shelf east of Delaware Bay and emptied into Wilmington Submarine Canyon. The ancestral valley (width, 3 to 8 kilometers; relief, 10 to 30 meters) is buried, is not reflected in the surface topography, and probably predates the formation of the present canyon head.

Eolian biogenic detritus in deep sea sediments: a possible index of equatorial ice age aridity.

Opal phytoliths and freshwater diatoms, transported mainly in dust to the equatorial Atlantic, are common in sediments deposited when ocean waters were cool, and sparse in those deposited when waters were warm, during the last 1.8 million years. Climate in source areas of the southern Sahara apparently was more arid during glacials and more humid during interglacials.

Opal phytoliths in a north atlantic dust fall.

Minute bodies (less than 80 microns) of isotropic silica, originally precipitated by terrestrial plants, are found together with freshwater diatoms in falls of dust over the ocean. Eolian transport from Africa can explain the occurrence of similar plant remains in deep-sea sediments of the equatorial Atlantic as far west as the Mid-Atlantic Ridge.