Postorogenic shoshonitic rocks and their origin by melting underplated basalts: The Miocene of Limnos, Greece
Georgia Pe-Piper et al., Department of Geology, Saint Mary's University, Halifax, Nova Scotia B3H 3C3, Canada. Pages 39-54.
Potassium-rich volcanic rocks, termed shoshonites, are a common feature of many mountain belts, including the Absaroka Range of Wyoming. Precisely how such volcanic rocks form and their relationship to mountain building processes is disputed. Unusual features of 20-million-year-old shoshonite volcanoes in the island of Limnos, Greece, demonstrate that the magma was largely derived by the melting of the lower part of the Earth's crust and Pe-Piper et al. argue that this process is of general applicability to this rock type. Formation of such volcanoes, thus, depends on a suitable source of heat from the Earth's mantle during mountain building processes.
Formation and dating of a salt pillar in Mount Sedom diapir, Israel
Amos Frumkin, Department of Geography, The Hebrew University of Jerusalem, 91905 Jerusalem, Israel. Pages 286-293.
The formation of a 20-meter-high salt pillar in Mount Sedom, Dead Sea area, was analyzed and dated in the study by Frumkin, and these results were complemented by measurement of present uplift rate because the pillar is a part of the actively rising Sedom diapir. Contrary to earlier assumptions, which stated that the salt pillar was formed by direct rainfall, the observed soluti
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