bay-mouth bar

geology

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Last updated

June 22, 2026

Quick Summary

A bay-mouth bar is a ridge of sand or gravel that forms across the entrance of a bay. This deposition, created by waves and currents, can either partially or completely block the opening, leaving the bay connected to the main body of water by only a narrow outlet.1

Sandbars, in general, are submerged or partially exposed ridges of sand built by wave action offshore from a beach. The process involves waves excavating a trough and depositing sand to form the bar. Bay-mouth bars are a specific type of sandbar that extends across a bay's mouth.2

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sandbar
Bay-mouth bars may extend partially or entirely across the mouth of a bay; bay-head bars occur at the heads of bays, a short distance from shore.
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Bay-mouth bars may extend partially or entirely across the mouth of a bay; bay-head bars occur at the heads of bays, a short distance from shore.
Read More