sole marking

geology

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Last updated

July 14, 2026

Quick Summary

Sole markings are geological features found on the bottom of a rock bed, commonly in sandstone and limestone layers that lie atop shale. These markings are essentially casts, formed by the filling of depressions on the surface of the underlying mud.1

Sole markings originate from several processes:
* Unequal loading on soft, wet mud.1
* The action of currents across the mud surface.1
* The activities of organisms on this surface.1

Load casts, for example, form when sandstone or limestone sinks into the mud below. Current marks can be created by water currents or by objects like wood and fossils being transported over soft sediment. These structures are valuable for geologists in understanding the depositional environment of rock layers.1

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sedimentary rock
Bedding structure
A great variety of markings, such as flutes and scour and fill grooves, can be found on the undersides of some sandstone beds. These markings are caused by swift currents during deposition; they are particularly abundant in sandstones deposited by turbidity currents.
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A great variety of markings, such as flutes and scour and fill grooves, can be found on the undersides of some sandstone beds. These markings are caused by swift currents during deposition; they are particularly abundant in sandstones deposited by turbidity currents.
Read More

sedimentary rock
Deformation structures
…of a bed are called sole markings, because they formed on the “sole” of the bed. Sole marks are commonly formed on sandstone and limestone beds that rest upon shale beds. They are termed casts, because they are fillings of depressions that formed on the surface of the underlying mud.…
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…of a bed are called sole markings, because they formed on the “sole” of the bed. Sole marks are commonly formed on sandstone and limestone beds that rest upon shale beds. They are termed casts, because they are fillings of depressions that formed on the surface of the underlying mud.…
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sedimentary rock
Wackes
…structures of wacke beds are sole markings, which occur on their undersurfaces. Flute and groove molds are the most characteristic, but many other structures have been recorded.
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…structures of wacke beds are sole markings, which occur on their undersurfaces. Flute and groove molds are the most characteristic, but many other structures have been recorded.
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