Molasse
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Molasse refers to the sandstones, shales and conglomerates formed as terrestrial or shallow marine deposits in front of rising mountain chains 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, 243)
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.(Stanley, 243)
[edit] References
- Stanley, Steven M. Earth System History. New York: W.H. Freeman and Company, 1999. ISBN 0-7167-2882-6
