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Cinder Cone is a 700 ft (210 m)-high volcanic cone of loose scoria. [5] The youngest mafic volcano in the Lassen volcanic center, [6] it is surrounded by unvegetated block lava and has concentric craters at its summit, [5] which have diameters of 1,050 ft (320 m) and 590 ft (180 m). [3]
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 ...
This list of shield volcanoes includes active, dormant and extinct shield volcanoes. Shield volcanoes are one of the three types [ specify ] of volcanoes. They have a short cone shape, and have basaltic lava which means the lava has low viscosity (viscosity is a measure of the ability for a liquid to flow)
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 ...
In a simplified compositional classification, igneous rock types are categorized into felsic or mafic based on the abundance of silicate minerals in the Bowen's Series. Rocks dominated by quartz, plagioclase, alkali feldspar and muscovite are felsic. Mafic rocks are primarily composed of biotite, hornblende, pyroxene and olivine.
Hoodoo Butte is one of the larger mafic volcanoes, along with Three Fingered Jack, North Sister, and the vents of the Mount Bachelor chain. [ 11 ] Sometimes considered a subfeature of the Mount Washington shield volcano, [ 12 ] Hoodoo forms one of several glaciated remnants of Pleistocene volcanoes in the region, other nearby examples including ...
An example is the massive Level Mountain shield volcano in northern British Columbia, Canada, which covers an area of 1,800 km 2 (690 sq mi) and a volume of 860 km 3 (210 cu mi). [ 1 ] Perhaps the most extensive of all the subaerial basaltic plateaus existed during the Paleogene [ 2 ] and possibly extended over 1,800,000 km 2 (690,000 sq mi) of ...