Is Precambarian Granite A Sedimentary Rock

Sedimentary rocks form as a result of weathering and deposition from previously formed rocks and are usually much softer than igneous or metamorphic rocks.

Is precambarian granite a sedimentary rock. 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. No granite is an igneous rock. They are characterized by abundant volcanic rocks that include pillowed subaqueous basalt flows and subaerial and subaqueous volcaniclastic rocks. They are composed of precambrian basement similar to that exposed in shields but overlain by 1 to 3 km of relatively undeformed sedimentary rock.

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

Sandstone is a sedimentary rock that is worn away by dirt and dust rubbing against it in the wind. It forms from the slow crystallization of magma below earth s surface. Basement rock is contrasted to overlying sedimentary rocks which are laid down on top of the basement rocks after the continent was formed such as sandstone and limestone the sedimentary rocks which may be deposited on. Granite is a light colored igneous rock with grains large enough to be visible with the unaided eye.

Greenstone granite belts such as those of the archean continued to form in the proterozoic albeit in greatly reduced amounts. Precambrian precambrian precambrian geology. Magnesian komatiites are for the most part absent however. One easy way to.

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. Sedimentary rocks are the most common rocks exposed on the earth s surface but are only a minor constituent of the entire crust.