Dolomite

Dolomites are fine to coarse grained rocks that are generally gray to light colored that weather buff (tan) because of impurites that commonly consist of iron (or small amounts of pyrite, siderite or marcasite) within or between dolomite crystals. It occurs in rocks of all ages, but is more abundant in older rocks. (forming about 1/4 of Paleozoic and about 3/4 of PreCambrian carbonate rocks. Dolomites may be formed by the same processes as limestone or by the breakdown and redeposition of older dolomites. They are also converted from limestone by a process called dolomitization. This involves the replacement of calcium by magnesium. The change may take place before or after the rock has been solidified and is caused by the action of seawater, ground water or hot mineral water. The subject of dolomite and dolomitization has been discussed and argued in the geologic literature for decades (and is continuing today) is known as the Dolomite Problem.

Among the surface rocks in Kansas, dolomite is found in three formations in the central and southern part of the state. The Stone Corral Dolomite (Permian) has a maximum thickness of about 6 feet in Rice County. The Day Creek Dolomite (Permian) is found in Clark County and is about 2 ½ feet thick. These formations were deposited in the enclosed evaporating basin of the Permian sea. A thick outcrop of dolomite is found in the southern Flint Hills.

Dolomite is used in ways similar to limestone.Kansas Geological Survey