Organic reef

Overview

A sedimentary system composed of a series of sedimentary facies in organic reefs such as coral reefs. Lagoon is formed by the biological activity of reef-forming corals. It is reported that dominant organisms in organic reefs are different in ages; Cambrian archeocyathids, Devonian stromatoporoids - rugose corals, Late Jurassic to Early Cretaceous stromatoporoids-hexacorallia, Late Cretaceous rudists, Neogene to present hexacorallia. The growth speed of modern coral reefs is estimated as 0.5 - 1.5 mm/year, and 6 mm/year in maximum.

Microcodium structures, Pendant cement, Scalenohedral cement, Crystal silt, Resolved cavities, and Alveolar structure are formed in the terrestrial freshwater diagenetic circumstances.