GEOLOGY

Detailed explanation-1: -Biologic sedimentary rocks form when living organisms die, pile up, and are then compressed and cemented together. Types of biologic sedimentary rock include coal (accumulated plant material that is carbon-rich), or limestone and coquina (rocks made of marine organisms).

Detailed explanation-2: -Limestone is a sedimentary rock composed principally of calcium carbonate (calcite) or the double carbonate of calcium and magnesium (dolomite). It is commonly composed of tiny fossils, shell fragments and other fossilized debris.

Detailed explanation-3: -Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years.

Detailed explanation-4: -Limestone is usually a biological sedimentary rock, forming from the accumulation of shell, coral, algal, fecal, and other organic debris. It can also form by chemical sedimentary processes, such as the precipitation of calcium carbonate from lake or ocean water.