41. CENOZOIC CLAY MINERALOGY OF SITES 604 AND 605, NEW JERSEY TRANSECT, DEEP SEA DRILLING PROJECT LEG 931

• Main Authors: Dean A. Dunn, David M. Patrick, Ulysses Cooley, Department Of Geology
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.619.2048; http://www.deepseadrilling.org/93/volume/dsdp93_41.pdf

Examination of the clay mineralogy of Cenozoic sediment samples from Deep Sea Drilling Project Sites 604 and 605 on the upper continental rise off New Jersey indicates that sediment deposition of two different clay mineral facies has occurred. These sites are marked by Paleogene deposition of illite with subordinate kaolinite and smectite covarying in inverse proportion, and by Neogene deposition dominated by illite with subordinate kaolinite and chlorite. Leg 93 re-sults agree with the clay mineral facies proposed by Hathaway (1972), which defined a "Northern facies " consisting of illite and chlorite, with feldspar and hornblende, from erosion of rocks north of Cape Hatteras, and a "Southern fa-cies " composed of smectite, kaolinite, and mixed-layer illite-smectites. Neogene and Quaternary sediments at Sites 604 and 605 contain the "Northern facies, " and Paleogene sediments contain the "Southern facies " minerals. Feldspar is exclusively found in Neogene-Quaternary sediments, as is the majority of the amphibole found in these samples. Wide-spread Paleogene volcanic source materials are suggested by the presence of smectite throughout the early Paleocene-middle Eocene sediments recovered at Site 605. The clay mineral stratigraphy at Leg 93 sites is comparable to the record at nearby DSDP sites on the lower continental rise and abyssal plain of the northwestern Atlantic (DSDP Sites 388, 105, and 106), and also with the sediments recovered by drilling on the Mazagan Plateau off northwestern Morocco (DSDP Sites 544-547) in the eastern North Atlantic.