Molasse identification and geology

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• Flysch
• Conglomerate
• Sandstone

Sources, scope & corrections

These authoritative resources support category-level nomenclature, terminology, identification methods, and safety. When a specimen-specific safety warning appears, the public-health source listed here directly supports that precaution. They are not line-by-line citations for every other property on this entry, and natural specimens vary.

Editorial owner

GeoMiner

Last updated

2026-03-30T14:39:17.405301+00:00

Review status

Published; not independently peer-reviewed

• Rocks — U.S. National Park Service. Authoritative overview of rock groups, the rock cycle, and geologic processes.
• Can you identify my rock or mineral? — U.S. Geological Survey. Identification limitations and routes to in-person professional verification.

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Common questions

What is Molasse?

Thick sequence of coarse continental sediments conglomerate, sandstone deposited in foreland basins after mountain uplift.

How can you identify Molasse?

Compare several properties rather than relying on colour alone. This entry records rock type: Sedimentary Clastic; texture: Coarse, poorly sorted; grain size: Coarse conglomerate to sandstone; common minerals: Quartz, Feldspar, Rock fragments, Clay. Confirm an important identification with additional field tests or qualified laboratory work.

How does Molasse form?

Deposited in foreland basins by rivers draining newly uplifted mountain belts. Represents post-orogenic erosion.

Where is Molasse commonly found?

Swiss Molasse Basin, Himalayan foreland, Appalachian foreland; post-orogenic continental deposits.

What is Molasse commonly confused with?

Molasse may be confused with Flysch, Conglomerate, Sandstone. Compare multiple diagnostic properties because colour and surface appearance can overlap.