scallop

cave feature

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July 13, 2026

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A scallop is a marine bivalve mollusk known for its fan-shaped shell with undulated edges. These mollusks, belonging to the family Pectinidae, are found worldwide and can swim by rhythmically clapping their shells. Scallops feed on microscopic organisms and possess numerous light-detecting eyes along the edge of their mantle.12

In geology, a scallop refers to a small, scoop-like depression found on cave walls and ceilings. These features are formed by water flow and are asymmetrical, with a steeper side upstream and a gentler slope downstream. The size of a scallop is inversely related to the water's flow velocity, allowing geologists to determine both the direction and speed of ancient water currents within caves.3

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cave
Solutional sculpturings
…small scooplike depressions known as scallops. Scallops vary in size from a few centimetres to more than one metre. They are asymmetrical in cross section, having a steep wall on the upstream side and a gentler slope on the downstream side. Scallops thus provide information as to the direction of…
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…small scooplike depressions known as scallops. Scallops vary in size from a few centimetres to more than one metre. They are asymmetrical in cross section, having a steep wall on the upstream side and a gentler slope on the downstream side. Scallops thus provide information as to the direction of…
Read More