A reef deposit is a type of sedimentary deposit that is formed by the accumulation of CORAL and other marine organisms. It is usually found in shallow, warm waters and is composed of calcium carbonate. The term 'reef deposit' is often used interchangeably with the term 'CORAL reef, ' which is a type of underwater structure that is formed by the accumulation of CORAL and other marine organisms. The term 'CORAL' is derived from the Latin word for 'HORN, ' and it refers to the hard, stony structures that are formed by the accumulation of calcium carbonate.