foreset bed

geology

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June 26, 2026

Quick Summary

A foreset is a layer of sediment deposited on the steeper, outer slope of a delta, or on the lee side of a dune. These layers are inclined seaward and are typically coarser near the river mouth, becoming finer in deeper water. Foreset beds are a key component of delta stratigraphy, representing the accumulation of sediment where a river meets a body of standing water. The angle of inclination can vary, with steeper angles observed in deposits like braid deltas. Foresets are part of a larger depositional sequence that includes topset and bottomset beds.123

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Deposits and stratigraphy
Foreset deposits accumulate in the subaqueous delta front zone. The deposits are usually coarser at the river mouth and become finer as they radiate seaward into deeper water. Strata in the foreset unit are inclined seaward at an angle reflecting that of the delta slope…
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Foreset deposits accumulate in the subaqueous delta front zone. The deposits are usually coarser at the river mouth and become finer as they radiate seaward into deeper water. Strata in the foreset unit are inclined seaward at an angle reflecting that of the delta slope…
Read More