Molasse

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Not to be confused with molasses.

Molasse refers to the sandstones, or less commonly shales formed as shore deposits, for example that left from the rising Alps, or erosion in the Himalaya. More generally, the term means the terrestrial deposits eroded from a mountain chain and deposited in a foreland basin, especially on top of flysch. 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)