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Highest point; Elevation: 6,896 ft (2,102 m) NGVD 29 [1] Coordinates: 1]: Geography; Location: Lassen and Shasta counties, California, U.S.: Parent range: Cascade Range: Topo map: USGS Prospect Peak: Geology; Mountain type: Extinct Cinder cone: Volcanic arc: Cascade Volcanic Arc: Last eruption: 1666: Climbing; Easiest route: Trail hike: Cinder Cone is a cinder cone volcano in Lassen Volcanic ...
A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include basalt, diabase and gabbro. Mafic rocks often also contain calcium-rich varieties of plagioclase ...
Cinder cones are also commonly found on the flanks of shield volcanoes, stratovolcanoes, and calderas. [3] For example, geologists have identified nearly 100 cinder cones on the flanks of Mauna Kea, a shield volcano located on the island of Hawaii. [3] Such cinder cones likely represent the final stages of activity of a mafic volcano. [11]
The youngest mafic volcano in the Lassen volcanic center, [53] it is surrounded by unvegetated block lava and has concentric craters at its summit. [52] Cinder Cone is comprised by five basaltic andesite and andesite lava flows, and it also has two cinder cone volcanoes, with two scoria cones, the first of which was mostly destroyed by lava ...
Diamond Head, Hawaii, is an example of a tuff cone, as is the island of Ka'ula. The glassy basaltic ash produced in such eruptions rapidly alters to palagonite as part of the process of lithification. [47] Although conventional mafic volcanism produce little ash, such ash as is formed may accumulate locally as significant deposits.
Belknap was the last volcano to erupt in the Three Sisters area. [21] Basaltic andesite dominates the eruptive material in the local mafic volcanoes, which range from early Pleistocene to Holocene age. [22] Belknap is one of the larger mafic volcanoes in the Sisters Reach, more than 30 of which run continuously along the segment. [22]
Some of the minerals found in the region are mafic (high Ca pyroxenes, e.g., augite)—these suggest volcanic material. The volcano is located at 7.40°S, 94.60°W. The authors of the paper consider the volcano to be an eroded shield volcano. Sub-circular depressions near the top are interpreted as caldera remnants. [36]
Peridotite, a type of ultramafic rock. Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta-igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are usually composed of greater than 90% mafic minerals (dark colored, high magnesium and iron content).