Is Precambarian Granite A Sedimentary Rock

After the precambrian geologic time intervals are commonly subdivided on the basis of the fossil record.

Is precambarian granite a sedimentary rock.

Precambrian precambrian precambrian geology. By international agreement precambrian time is divided into the archean eon occurring between roughly 4 0 billion years ago and 2 5 billion years ago and proterozoic eon occurring between 2 5 billion and 541 million years ago. One easy way to. Greenstone granite belts such as those of the archean continued to form in the proterozoic albeit in greatly reduced amounts.

Basement rock is the thick foundation of ancient and oldest metamorphic and igneous rock that forms the crust of continents often in the form of granite. Granite is a light colored igneous rock with grains large enough to be visible with the unaided eye. Sedimentary rocks on platforms range in age from precambrian to cenozoic and reach thicknesses up to 5 km as for instance in the williston basin in the north central united states. No granite is an igneous rock.

Sedimentary rock rock formed at or near the earth s surface by the accumulation and lithification of sediment or by the precipitation from solution at normal surface temperatures. They are composed of precambrian basement similar to that exposed in shields but overlain by 1 to 3 km of relatively undeformed sedimentary rock. It forms from the slow crystallization of magma below earth s surface. Sedimentary rocks form as a result of weathering and deposition from previously formed rocks and are usually much softer than igneous or metamorphic rocks.

Sandstone is a sedimentary rock that is worn away by dirt and dust rubbing against it in the wind. Sedimentary rocks are the most common rocks exposed on the earth s surface but are only a minor constituent of the entire crust. They are characterized by abundant volcanic rocks that include pillowed subaqueous basalt flows and subaerial and subaqueous volcaniclastic rocks. Granite is composed mainly of quartz and feldspar with minor amounts of mica amphiboles and other minerals this mineral composition usually gives granite a red pink gray or white color with dark mineral.

Granite is not the kind of rock that would form into sandstone. Magnesian komatiites are for the most part absent however.