A beach is a strip of land alongside a body of water, usually an ocean or sea, where sand, rocks and sometimes shells, marine plants and even small animals wash up. The beach is the result of erosion and deposition processes over a long period of time. The process starts when weathering – the gradual breakdown of rocks into smaller pieces – takes place. The rock particles are eroded by waves and the swirling action of currents, resulting in sandy sediment being carried away to create beaches.
Beaches are made up of a mix of materials, from coarse sand to pebbles and even small fragments of shells and coralline algae. Sand is the main constituent of all beaches, but other materials are also present depending on the location. Rocks, gravel, shingle, silt and small fragments of vegetation can all be found on some beaches. Some beaches contain fossils of plant and animal life from the distant past.
The formation of a beach is a complex process that involves many different natural and human activities. Some of the most important geological and geomorphological processes at play are attrition, abrasion, hydraulic action and corrosion. These processes are responsible for creating the distinctive features of a beach, such as a beach head, dunes and sandbars.
These natural processes take place over an extended period of time, so it is important to understand how a beach forms. A beach is a complex landform that changes over time, and it is often referred to as a dynamic shoreline because of its continuous alteration.
Many beaches have a number of distinct features that make them unique, such as a beach head (a headland that juts out into the sea), a ridge or bank that extends offshore from a beach (a sandbar) and the swirling turbulence of rips and channels that cut through sand bars.
A beach can also be defined by its surf break, which is a predictable type of wave that is created by an obstruction in the oceanbed. This could be a piece of coral, a submerged shipwreck, a jetty, a rocky outcrop or a reef. A good understanding of the various types of surf breaks is essential to reading a wave forecast.
This can help you understand what to expect from your day at the beach and where to go. To get you started, download our Can You Find? Picture Activity – it’s perfect for the kids as the summer holidays are fast approaching. This activity can be used online or as a hard copy worksheet. It is a fun and educational way to learn all about the things that make up a beach.