cinder cones

For the generic cinder cone, see cinder cone.Cinder Cone is a cinder cone volcano in Lassen Volcanic National Park (itself in Northern California in the United States). Within the park it is located about 10 miles (16 km) northeast of Lassen Peak and provides an excellent view of Brokeoff Mountain, Lassen Peak, and Chaos Crags. The cone was built to a height of 750 feet (225 m) above the surrounding area and spread ash over 30 square miles (78 km²). Then, like many cinder cones, it was snuffed out when several  basalt lava flows erupted from its base. These flows, called the Fantastic Lava Beds, spread northeast and southwest, and dammed creeks, first creating Snag Lake on the south and then Butte Lake to the north. Butte Lake is fed by water from Snag Lake seeping through the lava beds. Nobles Emigrant Trail goes around Snag Lake and follows the edge of the lava beds.
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A cinder cone or scoria cone is a steep, conical hill of volcanic fragments that accumulate around and downwind from a volcanic vent. The rock fragments, often called cinders or scoria, are glassy and contain numerous gas bubbles "frozen" into place as magma exploded into the air and then cooled quickly. Cinder cones range in size from tens to hundreds of meters tall.
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