A beach is a dynamic environment, a place where land and water meet. Its surface is made of unconsolidated sediments, ranging from fine to coarse sand, or even rock fragments, carbonate skeletons, and the remains of shells and coral. The sediment is deposited and moved by waves, wind, and gravity. Beach plants and animals use this habitat to survive.
The beach is also an important social and cultural space. It offers a respite from urban and suburban working life and provides a venue for introspection and self-awareness. People come to beaches to swim, sunbathe, and relax, and they seek out natural attractions such as sandbars and dunes for a sense of adventure and renewal. In the twentieth century, the beach became even more popular as inexpensive mass transit systems connected urban working-class neighborhoods to nearby shorelines and the Dixie Highway snaked from Chicago and the Great Lakes to Miami, the mecca for wintertime snowbirds.
In addition to their recreational value, beaches are critical for the survival of some species. They provide shelter to fish, birds, and sea turtles, which lay their eggs on ocean beaches. Crabs and insects feed on the material deposited on beaches, and some plant species grow in sand dunes.
A beach is a narrow, gently sloping strip of land that lies along the edge of an ocean or a lake. It is the product of years of weathering and erosion, as waves continually beat rocky cliffs, causing some rocks to come loose, and others to be worn down to tiny grains of sand. The sandy sediment that forms beaches is composed of quartz, some feldspars, and sometimes even the skeletal remains of marine organisms.
As sand is deposited, a beach gains a sand ridge called a horn. This sand ridge is a zone where the current that’s pushing away from the beach meets the current that’s moving toward the beach. The result is sand accumulating in the spot where the two pushing forces meet, with an embayment to the west (often referred to as the trough), and an horn to the east (often called the horn). The difference in elevation between the horns and the embayments is known as the slope of the beach.
Beaches are also shaped by the type of wave that hits them. Constructive waves, which allow the water to recede and beach particles to settle between them, create a firm beach surface that resists future erosion. Destructive waves, on the other hand, do not let the sediment settle, and are more likely to erode the beach.
A beach may contain minor relief features such as oscillation ripples, swash or rill furrows, and the well-known cusps, which are concave seaward. These feature types are created by the action of waves on a beach, and their shape can change dramatically with changing wave conditions. Bay head bars, sandbars that appear at the mouth of bays as ocean water rushes in, and underwater tidal deltas, fan-shaped deposits of course sediment, are also common.