Todra volcanic field

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Todra Volcanic Field
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Todra Volcanic Field
Highest point
Elevation 1,780 m (5,840 ft) [1]
Coordinates 17°41′N8°30′E / 17.68°N 8.5°E / 17.68; 8.5 Coordinates: 17°41′N8°30′E / 17.68°N 8.5°E / 17.68; 8.5 [1]

Todra volcanic field is a volcanic field in the Aïr region, Niger.

Volcanic field Area of the Earths crust prone to localized volcanic activity

A volcanic field is an area of the Earth's crust that is prone to localized volcanic activity. They usually contain 10 to 100 volcanoes such as cinder cones and are usually in clusters. Lava flows may also occur. They may occur as a monogenetic volcanic field or a polygenetic volcanic field.

Niger republic in Western Africa

Niger or the Niger, officially the Republic of the Niger, is a landlocked country in West Africa named after the Niger River. Niger is bordered by Libya to the northeast, Chad to the east, Nigeria to the south, Benin to the southwest, Burkina Faso and Mali to the west, and Algeria to the northwest. Niger covers a land area of almost 1,270,000 km2 (490,000 sq mi), making it the largest country in West Africa. Over 80% of its land area lies in the Sahara Desert. The country's predominantly Islamic population of about 21 million live mostly in clusters in the far south and west of the country. The capital and largest city is Niamey, located in Niger's southwest corner.

The field consists of about 150 volcanoes, whose position is fault controlled. Their eruption products (mainly basalt but also phonolite and trachyte) cover a surface of about 1,050 square kilometres (410 sq mi). [1]

In geology, a fault is a planar fracture or discontinuity in a volume of rock, across which there has been significant displacement as a result of rock-mass movement. Large faults within the Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes.

Basalt A magnesium- and iron-rich extrusive igneous rock

Basalt is a mafic extrusive igneous rock formed from the rapid cooling of magnesium-rich and iron-rich lava exposed at or very near the surface of a terrestrial planet or a moon. More than 90% of all volcanic rock on Earth is basalt. Basalt lava has a low viscosity, due to its low silica content, resulting in rapid lava flows that can spread over great areas before cooling and solidification. Flood basalt describes the formation in a series of lava basalt flows.

Phonolite subclass of extrusive volcanic rock

Phonolite is an uncommon extrusive rock, of intermediate chemical composition between felsic and mafic, with texture ranging from aphanitic (fine-grain) to porphyritic. Its intrusive equivalent is nepheline syenite.

The field may have had historical eruptions. [1]

See also

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Types of volcanic eruptions Basic mechanisms of eruption and variations

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Wells Gray-Clearwater volcanic field

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The Volcano (British Columbia) mountain in Canada

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Timeline of volcanism on Earth

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References

  1. 1 2 3 4 "Todra Volcanic Field". Global Volcanism Program . Smithsonian Institution.