@article{oai:u-ryukyu.repo.nii.ac.jp:02005287, author = {Shinjo, Ryuichi and Motoyama, Isao and Nakamura, Mamoru and Takaki, Yasuaki and Nishida, Hideaki and Morii, Yasuhiro and Tanaka, Hitoshi and 新城, 竜一 and 中村, 衛}, issue = {65}, journal = {琉球大学理学部紀要, Bulletin of the College of Science. University of the Ryukyus}, month = {Mar}, note = {As a part of the educational cruise (RN97 Cruise) for students of College of Science, University of the Ryukyus, by T/S Nagasaki Maru, the scientific survey is carried out during November 15 to 24, 1997. We dredge seafloor samples at several seaknolls which locate in the southern Okinawa Trough. Pumices and dacitic lava fragments are dredged. The rocks are quite fresh, and thus appear to be Quaternary eruptives, confirming the presence of continuous volcanic front from the northern Ryukyu Arc to the southern Ryukyu Arc. Surface sediment type varies depending on depositional settings. Sediments recovered by a grab sampler are composed of quartz sand in the continental shelf, biogenic calcareous sand in the Hokuto-Sekibi Bank and the Ryukyu Ridge, and mud in the Okinawa Trough. The radiolarian assemblage from the surface sediment sample in the Okinawa Trough is characterized by warm water species in accord with the oceanographic setting., 紀要論文}, pages = {39--51}, title = {Report on RN97 Cruise by T/S Nagasaki Maru in the Southern Okinawa Trough}, year = {1998} }