The Susitna River is a 313-mile (504 km) long river in the Southcentral Alaska. It is the 15th largest river in the United States, ranked by average discharge volume at its mouth. The river stretches from the Susitna Glacier to Cook Inlet's Knik Arm.
The Acasta Gneiss Complex, also called the Acasta Gneiss, is a body of felsic to ultramafic Archean basement rocks, gneisses, that form the northwestern edge of the Slave Craton in the Northwest Territories, Canada, about 300 km (190 mi) north of Yellowknife, Canada. This geologic complex consists largely of tonalitic and granodioritic gneisses and lesser amounts of mafic and ultramafic gneisses. It underlies and is largely concealed by thin, patchy cover of Quaternary glacial sediments over an area of about 13,000 km2 (5,000 sq mi). The Acasta Gneiss Complex contains fragments of the oldest known crust and record of more than a billion years of magmatism and metamorphism. The Acasta Gneiss Complex is exposed in a set of anticlinoriums within the foreland fold and thrust belt of the Paleoproterozoic Wopmay Orogen.
Hatcher Pass is a mountain pass through the southwest part of the Talkeetna Mountains, Alaska. It is named after Robert Hatcher, a prospector and miner. The nearest cities are Palmer and Wasilla approximately 12 miles (19 km) to the south, and Willow approximately 26 mi (42 km) to the west. The communities are at an elevation of approximately 250 ft (76 m) in the Mat-Su valley.
Little Susitna River (Dena'ina: Tsałtastnu) heads at Mint Glacier on Montana Peak, in Talkeetna Mountains at 61°51′30″N149°03′30″W, flows southwest to Cook Inlet, 13 miles (21 km) west of Anchorage, Alaska Cook Inlet Low.
The Talkeetna River is a river in Alaska.
Tukgahgo Mountain (TUG-a-ho) is a mountain in the Takshanuk Mountains in the U.S. state of Alaska with a peak elevation of 4,675 feet (1,425 m). It is located in Haines Borough, 3.5 miles (5.6 km) to the southwest of Chilkoot Lake and 16 miles (26 km) to the southwest of Skagway. Geological investigations of the veins in the mountain have revealed silver, gold, platinum, and palladium mineralization, derived from mid-Cretaceous events.
Chimney Rock State Park is a North Carolina state park in Chimney Rock, Rutherford County, North Carolina in the United States. The 8,014-acre (32.43 km2) park is located 25 miles (40 km) southeast of Asheville, North Carolina, and is owned and managed by the state of North Carolina.
The Talkeetna Mountains are a mountain range in Alaska. The Matanuska and Susitna River valleys, with towns such as Trapper Creek, Talkeetna, Wasilla, Palmer, Sutton, and Chickaloon, roughly bound the Talkeetnas in the westerly parts of the range. Sovereign Mountain rises to 8,849 feet (2,697 m) in the remote and heavily glaciated central part of the range. The east side of the range fronts a broad, about 100 miles (160 km) wide, lake-studded lowland of forests and swamps, across which rises the gigantic Mount Wrangell volcanic edifice. Alaska Highway 4 runs northward through this lowland. Hundreds of miles to the west Alaska Highway 3 runs along the western side of the Talkeetna range, with the Alaska Range directly west. Alaska Highway 1, running along the southern front of the Talkeetna Mountains, lies mainly in a valley marking a tectonic divide between the Jurassic and Cretaceous rocks of the accretionary wedge, island-arc, and basement rocks in the Peninsular terrane, and the Chugach Mountains in the Chugach terrane to the south. The range stretches as much as a hundred miles north to south. Alaska Highway 8, seasonal and unpaved, passes over highlands rising to above 4,000 feet (1,200 m), north of the Talkeetnas.
The Willow Creek mining district, also known as the Independence Mine/Hatcher Pass district, is a gold-mining area in the U.S. state of Alaska. Underground hard-rock mining of gold from quartz veins accounts for most of the mineral wealth extracted from the Hatcher Pass area. The first mining efforts were placer mining of stream gravels, and placer mining in the area has continued sporadically to this day. Robert Hatcher discovered gold and staked the first claim in the Willow Creek valley in September 1906. The first lode mill in the area started operating in 1908. Underground mining continued at a variety of locations around the pass until 1951. In the 1980s one of the area's hard-rock mines was briefly re-opened. At least one mining company is actively exploring for gold in the area now. Through 2006 the district produced 667-thousand ounces of hard rock gold and 60-thousand ounces of placer gold.
The South Pass greenstone belt is located within the Wyoming Craton in the United States. The region was the site of Wyoming's initial gold discovery in 1842.
The geology of Massachusetts includes numerous units of volcanic, intrusive igneous, metamorphic and sedimentary rocks formed within the last 1.2 billion years. The oldest formations are gneiss rocks in the Berkshires, which were metamorphosed from older rocks during the Proterozoic Grenville orogeny as the proto-North American continent Laurentia collided against proto-South America. Throughout the Paleozoic, overlapping the rapid diversification of multi-cellular life, a series of six island arcs collided with the Laurentian continental margin. Also termed continental terranes, these sections of continental rock typically formed offshore or onshore of the proto-African continent Gondwana and in many cases had experienced volcanic events and faulting before joining the Laurentian continent. These sequential collisions metamorphosed new rocks from sediments, created uplands and faults and resulted in widespread volcanic activity. Simultaneously, the collisions raised the Appalachian Mountains to the height of the current day Himalayas.
The Vishnu Basement Rocks is the name recommended for all Early Proterozoic crystalline rocks exposed in the Grand Canyon region. They form the crystalline basement rocks that underlie the Bass Limestone of the Unkar Group of the Grand Canyon Supergroup and the Tapeats Sandstone of the Tonto Group. These basement rocks have also been called the Vishnu Complex and Vishnu Metamorphic Complex. These Early Proterozoic crystalline rocks consist of metamorphic rocks that are collectively known as the Granite Gorge Metamorphic Suite; sections of the Vishnu Basement Rocks contain Early Paleoproterozoic granite, granitic pegmatite, aplite, and granodiorite that have intruded these metamorphic rocks, and also intrusive Early Paleoproterozoic ultramafic rocks.
The geology of Nigeria formed beginning in the Archean and Proterozoic eons of the Precambrian. The country forms the Nigerian Province and more than half of its surface is igneous and metamorphic crystalline basement rock from the Precambrian. Between 2.9 billion and 500 million years ago, Nigeria was affected by three major orogeny mountain-building events and related igneous intrusions. Following the Pan-African orogeny, in the Cambrian at the time that multi-cellular life proliferated, Nigeria began to experience regional sedimentation and witnessed new igneous intrusions. By the Cretaceous period of the late Mesozoic, massive sedimentation was underway in different basins, due to a large marine transgression. By the Eocene, in the Cenozoic, the region returned to terrestrial conditions.
The geology of Alaska includes Precambrian igneous and metamorphic rocks formed in offshore terranes and added to the western margin of North America from the Paleozoic through modern times. The region was submerged for much of the Paleozoic and Mesozoic and formed extensive oil and gas reserves due to tectonic activity in the Arctic Ocean. Alaska was largely ice free during the Pleistocene, allowing humans to migrate into the Americas.
The Ashe Metamorphic Suite, also referred to as the Ashe Formation, was named after its type locality, Ashe County, North Carolina. The Ashe Metamorphic Suite is located in the Eastern Blue Ridge providence that extends from North Carolina up to South-Western Virginia. It is a collection of metamorphic rocks of both sedimentary and volcanic origin. Zircon dating indicates an age of 470 to 335 Ma for the unit. The protolith of the Ashe Metamorphic Suite was deposited during the Late Proterozoic and reaching its cooling age during the end of the Devonian. The Ashe Metamorphic Suite is overwhelmingly composed of amphibolites and mica schists.
The Ammonoosuc Volcanics is a rock unit in parts of New Hampshire and Vermont in the United States. This unit is named for the Ammonoosuc River that runs through the portion of New Hampshire that houses the Ammonoosuc Volcanics.
Burks Mountain is an elevated area in Columbia County, Georgia. Its summit is 474 feet above sea level. It lies within a region of the Piedmont which is characterized mainly by a broad southwest-to-northeast area of felsic igneous and metamorphic rock such as gneiss, schist, granite, and phyllite, as mapped by J. H. Hetrich. Within the corresponding area dominated by felsic rock across the Savannah River in South Carolina, small bands of mafic rock such as amphibolite, and ultramafic rock such as dunite, soapstone, and serpentine are mapped by Horton and Dicken.
Bullion Mountain is a 5,086-foot-elevation (1,550-meter) summit in Alaska, United States.
Skyscraper Mountain is a 4,784-foot-elevation (1,458-meter) summit in Alaska, United States.
Troublemint Peak is a 6,801-foot-elevation (2,073-meter) summit in Alaska, United States.
