In geology, anorogenic magmatism is the formation, intrusion or eruption of magmas not directly connected with orogeny. This contrasts with orogenic magmatism that occurs at convergent plate boundaries where continental collision, subduction and orogeny are common.
Extensional tectonics is concerned with the structures formed by, and the tectonic processes associated with, the stretching of a planetary body's crust or lithosphere.Geology of Niger
The geology of Niger comprises very ancient igneous and metamorphic crystalline basement rocks in the west, more than 2.2 billion years old formed in the late Archean and Proterozoic eons of the Precambrian. The Volta Basin, Air Massif and the Iullemeden Basin began to form in the Neoproterozoic and Paleozoic, along with numerous ring complexes, as the region experienced events such as glaciation and the Pan-African orogeny. Today, Niger has extensive mineral resources due to complex mineralization and laterite weathering including uranium, molybdenum, iron, coal, silver, nickel, cobalt and other resources.Hotspot (geology)
In geology, the places known as hotspots or hot spots are volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle. Their position on the Earth's surface is independent of tectonic plate boundaries. There are two hypotheses that attempt to explain their origins. One suggests that hotspots are due to mantle plumes that rise as thermal diapirs from the core–mantle boundary. The other hypothesis is that lithospheric extension permits the passive rising of melt from shallow depths. This hypothesis considers the term "hotspot" to be a misnomer, asserting that the mantle source beneath them is, in fact, not anomalously hot at all. Well-known examples include the Hawaii, Iceland and Yellowstone hotspots.Noronha hotspot
Noronha hotspot is a hypothesized hotspot in the Atlantic Ocean. It has been proposed as the candidate source for volcanism in the Fernando de Noronha archipelago of Brazil, as well as of other volcanoes also in Brazil and even the Bahamas and the Central Atlantic Magmatic Province.
The presence of a mantle plume is controversial owing to equivocal seismic tomography images of the mantle and the inconsistent age progression in the volcanoes, especially the Brazilian ones.Tosham Hill range
Tosham hill range (Tusham hill range old spelling), located at and in the area around Tosham, with an average elevation of 207 meters (679 feet), and the rocks exposed in and around Tosham hills are part of subsurface north western spur of Alwar group of Delhi supergroup of Aravalli Mountain Range, belong to the Precambrian Malani igneous suite of rocks and have been dated at 732 Ma BP (million years before present). This range in Aravalli Craton is a remnant of the outer ring of a fallen chamber of an extinct volcano. Tosham hill range covers the hills at Tosham, Khanak and Riwasa as well as the small rocky outcrops at Nigana, Dulehri, Dharan, Dadam and Kharkari Makhwan. Among these, Khanak hill is the largest in area and tallest in height.
It is an important biodiversity area within the "western-southern Haryana" spur of the Northern Aravalli leopard wildlife corridor.West Potrillo Mountains
The West Potrillo Mountains are a mountain range in south central Doña Ana County, New Mexico, United States. They are located approximately 40 miles (64 km) northwest of El Paso, Texas, 25 miles (40 km) southwest of Las Cruces, New Mexico, and 35 miles (56 km) southeast of Deming, New Mexico Most of the mountains are located on land managed by the Bureau of Land Management as part of the Organ Mountains-Desert Peaks National Monument. Access to the vicinity is through Doña Ana County Road B-4 South from NM 549, which may be accessed from Interstate 10 Exit 116.
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