Activities of Japanese Party in McMurdo Sound Area During the 1978-1979 Field Season

Abstract

To carry out four research programs, three Japanese scientists visited McMurdo Station and Victoria Land for a period from October 27, 1978 to January 19, 1979. Search for Antarctic meteorites : A U. S. -Japan meteorites search project was continued in the 1978-79 season in Victoria Land. Four U. S. participants and three Japanese revisited the bare ice field in the Allan Hills in Victoria Land, 230km north of McMurdo Station. Newly selected searching sites for this season are located in the blue ice field around the Darwin Glacier, namely, Boomerang Range, Warren Range, Finger Ridges, Butcher Ridge, Upper Darwin Glacier, Darwin Mountains, Turnstile Ridge, Westhaven Nunatak, Bates Nunataks and Lonewolf Nunataks. During this season, a total of 310 individual specimens were collected. Glaciological survey in the Allan Hills bare ice field : To clarify the accumulation mechanism of many meteorites on the bare ice surface of a limited small area near the Allan Hills, a triangulation line about 15 km long was installed in the bare ice field on the plateau side of the Allan Hills during the period from December 7, 1978 to January 2, 1979. Ice samples for the dating and crystallography were collected from this bare ice field. Geological survey in the Dry Valley area : Survey of the basement metamorphic rocks was conducted in the Dry Valley and Miers Valley area. Many dikes and their mutual relationship near Vanda Station of the Wright Valley were surveyed. The succession of intrusion is as follows in order of time : Black-colored lamprophyre A and B, grey-colored lamprophyre, porphyry A, B, and C, granite porphyry A and B, felsitic dike, basalt (Ferrer dolerite) and acidic dike in dolerite. Sampling of palaeomagnetic rock specimens : About 420 specimens were collected from Mt. Circe, Mt. Fleming, Mt. Knobhead, Allan Hills, Carapace Nunatak and Ross Island area. These specimens consist of various gneisses, marble, and granitic varieties of the basement ; sandstone, shale, coal, and petrified wood of the Beacon Formation ; many dike rocks in the Beacon Formation ; Ferrer dolerite and McMurdo volcanic rocks.