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volcano

(Encyclopedia)volcano, vents or fissures in the earth's crust through which gases, molten rock, or lava, and solid fragments are discharged. Their study is called volcanology. The term volcano is commonly applied b...

Alaska Peninsula

(Encyclopedia)Alaska Peninsula, SW Alaska, extending 500 mi (800 km) SW from the mainland, separating Bristol Bay and the Bering Sea from Cook Inlet, the Shelikof Strait, and Pacific Ocean. The Aleutian Range, runn...

Virunga

(Encyclopedia)Virunga vēro͝ongˈgä [key], volcanic range of mountains, E Congo, N Rwanda, and SW Uganda, central Africa, NE of Lake Kivu. It extends along the eastern rim of the Great Rift Valley and separates t...

rhyolite

(Encyclopedia)rhyolite, fine-grained light-colored acidic volcanic rock. Rhyolite is chemically the equivalent of granite, and is thus composed primarily of quartz and orthoclase feldspar with subordinate amounts o...

Katahdin Woods and Waters National Monument

(Encyclopedia)Katahdin Woods and Waters National Monument kətäˈdĭn [key], 87,500 acres (35,400 hectares), N central Maine, est. 2016. Located E of Baxter State Park (the site of Mt. Katahdin) along the East Bra...

National Road

(Encyclopedia)National Road, U.S. highway built in the early 19th cent. At the time of its construction, the National Road was the most ambitious road-building project ever undertaken in the United States. It final...

national bank

(Encyclopedia)national bank, in the United States, financial institution of a class authorized by Congress in acts of 1863 and 1864. The acts were intended to provide a way of marketing the large bond issues made n...

Fort Bridger State Park

(Encyclopedia)Fort Bridger State Park, on Blacks Fork of the Green River, SW Wyo. The supply post, founded by U.S. fur trader James Bridger in 1843, was an important station on the Oregon Trail. The Mormons held Fo...

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