Preliminary report of the TH97 geological and geophysical survey results, north of the Antarctic Peninsula

• Main Authors: Tanahashi,Manabu, Nishimura,Akira, Oda,Hirokuni, Murakami,Fumitoshi
• Format: Report
• Language: English
• Published: Geological Survey of Japan/Geological Survey of Japan/Geological Survey of Japan/Technology Research Center, Japan National Oil Corporation 1999
• Subjects: Pacific Margin of the Antarctic Peninsula; Bransfield Strait; marine geological and geophysical surveys; sedimentary sequences; Antarctic; The Antarctic; Antarctic Peninsula; Austral; Pacific; Elephant Island; Antarc*; British Antarctic Survey; Polar geoscience
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=3052; http://id.nii.ac.jp/1291/00003052/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=3052&item_no=1&attribute_id=18&file_no=1

Geophysical and geological surveys of the Japan National Oil Corporation (JNOC) TH97 cruise on the R/V Hakurei-maru, in the Pacific margin of the northern part of the Antarctic Peninsula, were carried out in the 1997-98 austral summer season. The cruise was devoted to the western, northern and eastern continental margins of the northern part of the Antarctic Peninsula. The seismic data are interpreted together with the data which were collected in this area during JNOC TH80, 88, 96 and PetroBras and British Antarctic Survey cruises. The area north of the Antarctic Peninsula is interpreted as the triple junction area among the Antarctic-Scotia-(former) Phoenix plates. The seismic data on the continental shelf of the northern part of the Antarctic Peninsula show distributed highly deformed sedimentary basins and volcanic features. Kr-Ar dating of fresh andesite recovered from a minor ridge south of Elephant Island gave a 7 to 8 Ma, Late Miocene age. It suggests the Late Miocene tectonic event which outlined the tectonic framework in the area. The deformation trend is interpreted to be controlled by the regional trend of sinistral transtensional movement between the Antarctic and Scotia plates.