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Kerimasi
Kerimasi Volcano, also known as Kerimasi (''Mlima Kerimasi'', in Swahili language, Swahili) at is an Extinct Volcano, extinct shield volcano located in Monduli District, Arusha, Monduli District of Arusha Region in Tanzania. The majority of the mountain lies in Engaruka, Monduli, Engaruka Ward, and a quarter of it is in the Ngorongoro Conservation Area. The volcano is located in the geographic area known as the Crater Highlands and is a shield volcano that last erupted in the Pleistocene. Geology and Mineral composition Kerimasi, an extinct nephelinite volcano in northern Tanzania's eastern rift valley, emitted carbonatite tephra during its final eruptive phase. The tephra was primarily composed of alkali carbonatite, making it the earliest well-documented example of premodern natrocarbonatite volcanism. The main carbonate mineral was nyerereite, which is also the major mineral in present natrocarbonatite lava flows from the neighboring volcano Ol Doinyo Lengai, Oldoinyo Lengai. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonatite
Carbonatite () is a type of intrusive rock, intrusive or extrusive rock, extrusive igneous rock defined by mineralogic composition consisting of greater than 50% carbonate minerals. Carbonatites may be confused with marble and may require geochemical verification. Carbonatites usually occur as small volcanic plug, plugs within zoned alkalic intrusive complexes, or as dike (geology), dikes, sill (geology), sills, breccias, and vein (geology), veins. They are almost exclusively associated with continental rift-related tectonic settings. It seems that there has been a steady increase in the carbonatitic igneous activity through the Earth's history, from the Archean Eon (geology), eon to the present. Nearly all carbonatite occurrences are intrusives or subvolcanic rock, subvolcanic intrusives. This is because carbonatite lava flows, being composed largely of soluble carbonates, are easily weathered and are therefore unlikely to be preserved in the geologic record. Carbonatite erupti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
