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Water and the Hydrosphere
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Ground that is frozen year round is called permafrost; Figure 12.37 shows permafrost on Svalbard, a Norwegian island. Stone rings, such as those shown in Figure 12.37, are one kind of patterned ground, features formed by repeated freezing and thawing, common natural features in some permafrost regions. Earth contains about 60 million square kilometers of permafrost, mostly in polar regions. Small amounts are also found at high elevations in the Rocky Mountains, the Himalaya, and elsewhere. In many places, the uppermost layers of permafrost melt during the summer and can support vegetation and other life. Permafrost is disappearing with global warming, but there is much uncertainty about the rate. Some scientists are concerned that melting of Arctic permafrost could release large amounts of methane that is presently trapped in frozen soils. More methane, a potent greenhouse gas, in the atmosphere could cause the rate of global warming to increase.
Landslides in the Transantarctic Mountains: lower Jurassic and older strata displaced in late Mesozoic to late Cenozoic time
Published in New Zealand Journal of Geology and Geophysics, 2022
Given the position of the slide, it is most probable that it occurred at a time when a steep slope or cliff consisting of those formations plus the Kirkpatrick Basalt was located adjacent to and approximately southwest of the slide, assuming the strike of the Kirkpatrick lavas in the slide block is perpendicular to the transport direction. Subsequently, the cliff or slope retreated as sub-aerial erosion processes created the ridge on which the extant slide is now located. Surficial debris was deposited later on the east slope of the ridge, and subsequently transformed into patterned ground. The northwest flank of today’s ridge falls more than 1000 m to the Prebble Glacier, whereas the southeast flank merges into the high ground that connects Mt. Falla to Mt. Kirkpatrick.