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Argillaceous Slate
Argillite () is a fine-grained sedimentary rock composed predominantly of indurated clay particles. Argillaceous rocks are basically lithified muds and oozes. They contain variable amounts of silt-sized particles. The argillites grade into shale when the fissile layering typical of shale is developed. Another name for poorly lithified argillites is ''mudstone''. These rocks, although variable in composition, are typically high in aluminium and silica with variable alkali and alkaline earth cations. The term ''pelitic'' or ''pelite'' is often applied to these sediments and rocks. Metamorphism of argillites produces slate, phyllite, and pelitic schist. Belt Supergroup The Belt Supergroup, an assemblage of rocks of late Precambrian (Mesoproterozoic) age, includes thick sequences of argillite, as well as other metamorphosed or semi-metamorphosed mudstones.Schieber, J. 1990. Significance of styles of epicontinental shale sedimentation in the Belt basin, Mid-Proterozoic of Montana, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Haida Gwaii
Haida Gwaii (; / , literally "Islands of the Haida people"), previously known as the Queen Charlotte Islands, is an archipelago located between off the British Columbia Coast, northern Pacific coast in the Canadian province of British Columbia. The islands are separated from the mainland to the east by the shallow Hecate Strait. Queen Charlotte Sound (Canada), Queen Charlotte Sound lies to the south, with Vancouver Island beyond. To the north, the disputed Dixon Entrance separates Haida Gwaii from the Alexander Archipelago in the U.S. state of Alaska. Haida Gwaii consists of two main islands: Graham Island () in the north and Moresby Island (, or "Islands of Beauty") in the south, along with approximately 400 smaller islands with a total landmass of . Other major islands include Anthony Island (British Columbia), Anthony Island (), Burnaby Island (), Langara Island (), Lyell Island (), Louise Island, (), Alder Island (Haida Gwaii), Alder Island and Kunghit Island (). On June ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sediment
Sediment is a solid material that is transported to a new location where it is deposited. It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently sediment transport, transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension (chemistry), suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial, fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and stream channel, river channel deposits are examples of fluvial transport and deposition (geology), deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Glacier National Park (U
Glacier National Park may refer to: * Glacier National Park (Canada), in British Columbia, Canada * Glacier National Park (U.S.), in Montana, USA See also * Glacier Bay National Park, in Alaska, USA * Los Glaciares National Park, in Patagonia, Argentina {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Flathead Lake
Flathead Lake (, ) is a large natural lake in northwest Montana, United States. The lake is a remnant of the ancient, massive glacial dammed lake, Glacial Lake Missoula, Lake Missoula, of the era of the last interglacial. Flathead Lake is a natural lake along the mainline of the Flathead River. It was dammed in 1930 by Kerr Dam at its outlet on Polson Bay, slightly raising the lake level; the dam generates electricity.Kerr Dam PPL Montana The hydroelectric has been owned and operated by the Confederated Salish and Kootenai Tribes since 2015. It is one of the cleanest lakes in the populated world for its size and type.Flathead Lak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Missoula, Montana
Missoula ( ) is a city in and the county seat of Missoula County, Montana, United States. It is located along the Clark Fork River near its confluence with the Bitterroot and Blackfoot rivers in western Montana and at the convergence of five mountain ranges, and thus it is often described as the "hub of five valleys". The population was 73,489 at the 2020 census, and was estimated to be 78,204 in 2024. Missoula and Mineral Counties are included in the Missoula metropolitan area at 127,741 in 2024. Missoula is the second-largest city and second-largest metropolitan area in Montana. Missoula is home to the University of Montana, a public research university. The Missoula area was settled by people of European descent from 1858, including William T. Hamilton, who set up a trading post along the Rattlesnake Creek; Captain Richard Grant, who settled near Grant Creek; and David Pattee, who settled near Pattee Canyon. Missoula was founded in 1860 as Hellgate Trading Post while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bitterroot Mountains
The Northern and Central Bitterroot Range, collectively the Bitterroot Mountains ( Salish: čkʷlkʷqin), is the largest portion of the Bitterroot Range, part of the Rocky Mountains and Idaho Batholith, located in the panhandle of Idaho and westernmost Montana in the northwestern United States. The mountains encompass an area of . The mountains are bordered on the north by Lolo Creek, to the northeast by the Clark Fork, on the south by the Salmon River, on the east by the Bitterroot River and Valley, and on the west by the Selway and Lochsa Rivers. Its highest summit is Trapper Peak, at . __TOC__ Northern Bitterroot Range The Northern Bitterroot Range is the northernmost and shortest subrange of the Bitterroot Mountains. The Northern Bitterroots encompass and its two tallest peaks are the Rhodes Peak and the Quartz Benchmark. The Northern Bitterroots also contain a smaller subrange, the Grave Creek Range. The Grave Creek Range is in area and its highest peak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bitterroot Valley
The Bitterroot Valley is located in southwestern Montana, along the Bitterroot River between the Bitterroot Range and Sapphire Mountains, in the Northwestern United States. Geography The valley extends approximately from Lost Trail Pass in Idaho, where it is narrow, to a point near the city of Missoula along Interstate 90 where it is wider and flatter. To the west is the Bitterroot Range and its large Selway-Bitterroot Wilderness, Selway-Bitterroot Wilderness Area, and to the east is the smaller Sapphire Mountains and their Anaconda-Pintler Wilderness, Anaconda-Pintler Wilderness Area. The Bitterroot Range has steep faces, deep canyons, is heavily forested, and is within the Bitterroot National Forest. The Sapphire Mountains are more rounded, drier, and much less forested. The southern end of the valley is split into the East and West Forks of the Bitterroot River, and the northern end has the confluence of the Bitterroot River with the Clark Fork River. Connecting into the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Montana
Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, and the Provinces and territories of Canada, Canadian provinces of Alberta, British Columbia, and Saskatchewan to the north. It is the List of U.S. states and territories by area, fourth-largest state by area, but the List of U.S. states and territories by population, eighth-least populous state and the List of U.S. states and territories by population density, third-least densely populated state. Its List of capitals in the United States, capital is Helena, Montana, Helena, while the List of municipalities in Montana, most populous city is Billings, Montana, Billings. The western half of the state contains numerous mountain ranges, while the eastern half is characterized by western prairie terrain and badlands, with smaller mountain ranges f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Mesoproterozoic
The Mesoproterozoic Era is a geologic era that occurred from . The Mesoproterozoic was the first era of Earth's history for which a fairly definitive geological record survives. Continents existed during the preceding era (the Paleoproterozoic), but little is known about them. The continental masses of the Mesoproterozoic were more or less the same ones that exist today, although their arrangement on the Earth's surface was different. Major events and characteristics The major events of this era are the breakup of the Columbia supercontinent, the formation of the Rodinia supercontinent, and the evolution of sexual reproduction. This era is marked by the further development of continental plates and plate tectonics. The supercontinent of Columbia broke up between 1500 and 1350 million years ago, and the fragments reassembled into the supercontinent of Rodinia around 1100 to 900 million years ago, on the time boundary between the Mesoproterozoic and the subsequent Neoprot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Precambrian
The Precambrian ( ; or pre-Cambrian, sometimes abbreviated pC, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the Phanerozoic Eon, which is named after Cambria, the Latinized name for Wales, where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean, Archean, Proterozoic) of the geologic time scale. It spans from the formation of Earth about 4.6 billion years ago ( Ga) to the beginning of the Cambrian Period, about million years ago ( Ma), when hard-shelled creatures first appeared in abundance. Overview Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history, and what is known has largely been discovered from the 1960s onwards. The Precambrian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Belt Supergroup
The Belt Supergroup is an assemblage of primarily fine-grained sedimentary rocks and mafic intrusive rocks of late Precambrian (Mesoproterozoic) age. It is more than thick, covers an area of some 200,000 km2 (77,220 sq. mi), and is considered to be one of the world's best-exposed and most accessible sequences of Mesoproterozoic rocks. It was named after the Big Belt Mountains in west-central Montana. It is present in western Montana and northern Idaho, with minor occurrences in northeastern Washington (U.S. state), Washington and western Wyoming. It extends into Canada where the equivalent rocks, which are called the Purcell Supergroup, are exposed in southeastern British Columbia and southwestern Alberta. The rocks of the Belt Supergroup contain economically significant deposits of lead, zinc, silver, copper, gold, and other metals in a number of areas, and some of the Belt rocks contain fossil stromatolites. Spectacular outcrops of Belt rocks can be seen in Glacier National Par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Schist
Schist ( ) is a medium-grained metamorphic rock generally derived from fine-grained sedimentary rock, like shale. It shows pronounced ''schistosity'' (named for the rock). This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes or plates. This texture (geology), texture reflects a high content of platy minerals, such as mica, talc, chlorite group, chlorite, or graphite. These are often interleaved with more granular minerals, such as feldspar or quartz. Schist typically forms during regional metamorphism accompanying the process of mountain building (orogeny) and usually reflects a medium Metamorphism#Metamorphic grades, grade of metamorphism. Schist can form from many different kinds of rocks, including sedimentary rocks such as mudstones and igneous rocks such as tuffs. Schist metamorphosed from mudstone is particularly common and is often very rich in mica (a ''mica schis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
