Anorthosite

Anorthosite ( /ænˈɔrθəsaɪt/) is a phaneritic, intrusive igneous rock characterized by a predominance of plagioclase feldspar (90–100%), and a minimal mafic component (0–10%). Pyroxene, ilmenite, magnetite, and olivine are the mafic minerals most commonly present.

Anorthosite on Earth can be divided into two types: Proterozoic anorthosite (also known as massif or massif-type anorthosite) and Archean anorthosite. These two types of anorthosite have different modes of occurrence, appear to be restricted to different periods in Earth's history, and are thought to have had different origins.

Lunar anorthosites constitute the light-coloured areas of the Moon's surface and have been the subject of much research.

Read more about Anorthosite:  Archaean Anorthosite, Economic Value of Anorthosite

Other articles related to "anorthosite, anorthosites":

Baddeleyite - Geologic Occurrence
... rocks of layered mafic intrusions, diabase dikes, gabbroid sills and anorthosite ... from some anorthositic rocks in Proterozoic anorthosite complexes ... Places where these Proterozoic anorthosite complexes can be found are the Laramie Anorthosite Complex in Wyoming, the Nain and Grenville provinces of Canada, the Vico Volcanic Complex ...
Wyoming Craton - Accretion Events
... Mesoproterozoic (~1.4 Ga) anorthosite and syenites of the Laramie Anorthosite Complex and granite (ilmenite-bearing Sherman Granite) intrude into rocks of the Colorado orogen in the Laramie ... Both the anorthosite and granite transect the Cheyenne belt in the Laramide Mountains, and intrude crystalline rocks of the Wyoming province ...
Metamorphisis of Oddanchatram
... Oddanchatram is an anorthosite area ... The anorthosite is clearly intrusive into the country rock and contains many large inclusions of previously deformed basic granulite and quartzite within 100 meters of ... Both this intrusion and the nearby Kaduvar anorthosite show evidence of having been affected by later metamorphism and deformation ...
Economic Value of Anorthosite
... The primary economic value of anorthosite bodies is the titanium-bearing oxide ilmenite ... However, some Proterozoic anorthosite bodies have large amounts of labradorite, which is quarried for its value as both a gemstone and a building material ... Archean anorthosites, because they are calcium-rich, have large amounts of aluminium substituting for silicon a few of these bodies are mined as ores ...
Split Rock Lighthouse State Park - Natural History - Geology
... These flows also carried with them blocks of anorthosite, an even harder rock from the base of the Earth's crust, which became interspersed randomly in the diabase ... Three large blocks of anorthosite form Corundum Point, Day Hill, and Stony Point beneath the lighthouse ... rock, leaving behind hills and ridges of the harder diabase and anorthosite ...