Petrogenesis of a Phonolite-Trachyte Succession at Mount Sidley, Marie Byrd Land, Antarctica
نویسندگان
چکیده
منابع مشابه
Holocene deglaciation of Marie Byrd Land, West Antarctica.
Surface exposure ages of glacial deposits in the Ford Ranges of western Marie Byrd Land indicate continuous thinning of the West Antarctic Ice Sheet by more than 700 meters near the coast throughout the past 10,000 years. Deglaciation lagged the disappearance of ice sheets in the Northern Hemisphere by thousands of years and may still be under way. These results provide further evidence that pa...
متن کاملSelective glacial erosion and weathering zones in the coastal mountains of Marie Byrd Land, Antarctica
In the coastal mountains of Marie Byrd Land, Antarctica, there is a juxtaposition of ice moulded landforms at lower altitudes and upstanding summits with weathered surfaces bearing tors. This paper uses geomorphological mapping and exposure dating to test two hypotheses commonly used to explain such a landscape contrast: either the pattern reflects contrasts in glacial erosion related to the ba...
متن کاملEastern margin of the Ross Sea Rift in western Marie Byrd Land, Antarctica: Crustal structure and tectonic development
[1] The basement rock and structures of the Ross Sea rift are exposed in coastal western Marie Byrd Land (wMBL), West Antarctica. Thinned, extended continental crust forms wMBL and the eastern Ross Sea continental shelf, where faults control the regional basin-and range-type topography at 20 km spacing. Onshore in the Ford Ranges and Rockefeller Mountains of wMBL, basement rocks consist of Earl...
متن کاملPetrogenesis of Mount St. Helens Dacitic Magmas
The most frequent and voluminous eruptive Kurasawa, 1983], (4) partial melting of the lower crust products at Mount St. Helens are dacitic in composition, [e.g., Grant et al., 1984; Reid and Cole, 1983], and (5) although a wide variety of magma types (basalt to formation of compositional gradients in response to rhyodacite) is represented. To address the petrogenesis of convective and diffusive...
متن کاملFlow dynamics of Byrd Glacier, East Antarctica
Force-balance calculations on Byrd Glacier, East Antarctica, reveal large spatial variations in the along-flow component of driving stress with corresponding sticky spots that are stationary over time. On the large scale, flow resistance is partitioned between basal (�80%) and lateral (�20%) drag. Ice flow is due mostly to basal sliding and concentrated vertical shear in the basal ice layers, i...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Petrology
سال: 1997
ISSN: 1460-2415
DOI: 10.1093/petrology/38.9.1225