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__NOTOC__ The term "molasse" refers to the sandstones, shales and conglomerates formed as terrestrial or shallow marine deposits in front of rising mountain chains. The molasse is deposited in a foreland basin, especially on top of flysch, for example that left from the rising Alps, or erosion in the Himalaya. These deposits are typically the non-marine alluvial and fluvial sediments of lowlands, as compared to deep-water flysch sediments. Sedimentation stops once the orogeny stops, or once the mountains have eroded flat.〔 Stanley, Steven M., ''Earth System History'', New York: W.H. Freeman and Company, 1999, p.243 ISBN 0-7167-2882-6 〕 The molasse can sometimes completely fill a foreland basin, creating a nearly flat depositional surface, that nonetheless remains a structural syncline. Molasse can be very thick near the mountain front, but usually thins out towards the interior of a craton; such massive, convex accumulations of sediment are known as ''clastic wedges''.〔 ==See also== *Geology of the Himalaya *Molasse basin 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「molasse」の詳細全文を読む スポンサード リンク
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