Offshore Bar

sandbar

 or offshore bar

Submerged or partly exposed ridge of sand or coarse sediment that is built by waves offshore from a beach. The swirling turbulence of waves breaking off a beach excavates a trough in the sandy bottom. Some of this sand is carried forward onto the beach and the rest is deposited on the offshore flank of the trough. Sand suspended in the backwash and in rip currents adds to the bar, as does some sand moving shoreward from deeper water. The bar's top is kept below still-water level by the plunge of the waves breaking over it.

---

offshore bar [′ȯf¦shȯr ′bär]

(geology)

longshore bar

---

Offshore Bar 

the simplest coastal accumulative relief form, formed by the action of sweeping breakers. The bar has the form of a low ridge (bar), extending along the shoreline. Bars can reach hundreds of m or several km in length and 1–4 m in height; they are defined by the energy of the surf. Such bars are made of sand, gravel, pebbles, and shells. Ancient offshore bars are relicts of the old shoreline.