The beach is a place where people gather to swim, sunbathe, and enjoy the sea. It’s also an ideal place to unwind, relax, and re-energize after work or school. Moreover, it is often an inexpensive and convenient way to spend time with family and friends.
The physical features of a beach are determined by the materials it is made from. The sand, pebbles, and other materials that make up the beach are primarily the products of weathering and erosion. The continual action of waves beating against rocky cliffs can wear away small rocks and even large boulders, leaving only sand grains to cover the beach.
Beach material is typically light in color, but the type of rock that eroded to create the beach may give it a specific shade. For example, in Hawaii many beaches have black sand because of the presence of black basalt in the area. Other beaches are white because of the availability of coral or a mineral called white quart.
Some beaches are naturally colored, with minerals in the sand that leave an iron stain on the surface. These stains are lighter than the color of the actual sand, and can range from light yellow to brown. The oxidized stains of shells and other marine organisms are also commonly present on the beach’s surface.
As a result of this natural process, beaches can be varied in color, and they often vary widely between locations along the same shoreline. In fact, some beaches are so different from one another that they have a completely different appearance to them when viewed at any given time of the day or year.
Coastal sands are usually a mix of silt and sand. This mixture is usually a combination of sand from the local watershed and sand from areas that have been recently eroded by waves, wind, or other processes. It is this mix of materials that makes the beach’s color unique.
Other factors that can affect the beach’s profile include the weather and water level of the surrounding area, as well as changes in local surface water flows. For example, changes in water flow due to flooding or the dilution of surface water with stormwater drains can alter a beach’s bedforms.
A beach is also shaped by the waves that form on the ocean’s surface and a tidal river that runs into it. These waves, which are a natural part of the tides, can be either constructive (bringing sediment) or destructive (taking sediment).
When waves are destructive, they can break through a sand beach and sweep away sand and other material. When waves are constructive, they allow sand to settle in place before the next wave arrives and breaks.
Because of this, a beach’s surface can change over the course of a year and even over a decade or more. These changes can cause a sand beach to look different than it did in the past, and can lead to a variety of new beach forms such as dunes or beaches that are entirely composed of sand and other materials. These changes can also lead to the growth of new vegetation, which can help protect a beach from erosion.