Grainstone
Encyclopedia
Under the Dunham classification
, grainstones are grain-supported carbonate
sedimentary rocks that contain no micrite
. The spaces between grains are filled with sparry cement
.
Dunham classification
The Dunham classification system for carbonate sedimentary rocks was devised by Robert J. Dunham in 1964, and refined by Embry and Klovan in 1971 to include sediments that were organically bound during deposition.-History:...
, grainstones are grain-supported carbonate
Carbonate
In chemistry, a carbonate is a salt of carbonic acid, characterized by the presence of the carbonate ion, . The name may also mean an ester of carbonic acid, an organic compound containing the carbonate group C2....
sedimentary rocks that contain no micrite
Micrite
Micrite is a limestone constituent formed of calcareous particles ranging in diameter up to 4 μm formed by the recrystallization of lime mud.The term was coined in 1959 by Robert Folk for his carbonate rock classification system...
. The spaces between grains are filled with sparry cement
Cement
In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. The word "cement" traces to the Romans, who used the term opus caementicium to describe masonry resembling modern concrete that was made from crushed...
.