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Crazy Mountains
The Crazy Mountains, often called the Crazies, is a mountain range in the Central Montana Alkalic Province in the U.S. state of Montana. They are a part of the northern Rocky Mountains. Geography Spanning a distance of 40 miles (64 km), the Crazy Mountains are located between the Musselshell and Yellowstone rivers. The highest peak is Crazy Peak at . Rising over above the Great plains to the east, the Crazies dominate their surroundings and are plainly visible just north of Interstate 90. The Crazy Mountains form an isolated island range east of the Continental Divide. Other isolated ranges in Montana include the Castle Mountains, Little Belt Mountains, Big Snowy Mountains, Little Snowy Mountains, Bears Paw Mountains, Judith Mountains, North and South Moccasin Mountains, Highwood Mountains, Little Rocky Mountains, Sweet Grass Hills, Bull Mountains and, in the southeastern corner of the state near Ekalaka, the Long Pines. Geology The Big Timber Stock, a la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Montana Alkalic Province
The central Montana Alkalic Province is located in the United States in central Montana. Montana is bordered by Idaho, Wyoming, North Dakota, South Dakota, and Canada to the north. Central Montana is unique when compared to the rest of the Rocky Mountains due to its east-west trend of tectonic features, including thrust fault zones, anticlines, and domes. The area of tectonic activity experienced conditions of plastic deformation, which affected the whole region. The Montana Alkalic Province consist of Cretaceous intrusions of monzonite and syenite as well as Cambrian limestone, sandstone, and siltstone. Most of the sedimentary rocks are a result of deposition from a terrestrial fluvial environment. Deposition included more than 13,000 feet of clastics that were later uplifted. The peak of this uplifting occurred during the Devonian. Deposition, uplift, and traps of carbonate shales have made central Montana prime for small-scale oil and gas production. Other geologic formations in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bull Mountains
The Bull Mountains, el. , are a mountain range of the Rocky Mountains located in Yellowstone and Musselshell Counties in the U.S. state of Montana, lying northeast of Billings and south of Roundup.They are a lower elevation mountain range compared to other ranges in the same geographic region. Vegetation consists primarily of grassy meadows, tracts of sagebrush, and ponderosa pine forests, with the western half of the range being slightly more forested than the eastern half of the range. While the Bull Mountains are decent habitat for mule deer, Merriam's turkeys, bobcats, mountain lions, and elk, hunting and other recreational activities are limited unless an outfitter is hired, as there is little public land in the range. See also * List of mountain ranges in Montana This is a list of mountain ranges in the state of Montana. Montana is the fourth largest state in the United States and is well known for its mountains. The name "Montana" means "mountainous" in Latin. Represent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweet Grass County, Montana
Sweet Grass County is a county located in the U.S. state of Montana. As of the 2020 census, the population was 3,678. Its county seat is Big Timber. The county was founded in 1895. History The Montana Legislature authorized Sweet Grass County in 1895, taking parts of Park, Meagher, and Yellowstone counties. That boundary was altered in 1913 when Stillwater County was formed from a portion of Sweet Grass; again in 1917 with the formation of Wheatland County, and in 1920 with the formation of Golden Valley County. Climate Sweet Grass County's climate is generally dry and cool, specified as Dfc in the Köppen-Geiger climate classification (subarctic or boreal). Average annual precipitation of 15 inches (380mm) comes in rain and snow. The summer precipitation accumulation (April through September) averages 10.5 inches (267mm). The average summer high temperature is 75.3 °F (24 °C) and the average minimum temperature during that period is 44.2 °F (6.8 °C). July and August a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meagher County, Montana
Meagher County (pronounced Marr) is a county located in the U.S. state of Montana. As of the 2020 census, the population was 1,927. Its county seat is White Sulphur Springs. According to the United States Census Bureau, the 2010 center of population of Montana is located in Meagher County at History Meagher County was named for Thomas Francis Meagher, territorial governor of Montana. The first county seat was Diamond City, the main city of the Confederate Gulch mining district. This area is no longer part of Meagher County, but today lies in neighboring Broadwater County. Geography According to the United States Census Bureau, the county has a total area of , of which is land and (0.1%) is water. Major highways * U.S. Highway 12 * U.S. Highway 89 Adjacent counties * Cascade County - north * Judith Basin County - northeast * Wheatland County - east * Sweet Grass County - southeast * Park County - south * Gallatin County - south * Broadwater County - west * Le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sweet Grass Creek
Sweet Grass Creek is a tributary of the Yellowstone River, approximately 50 mi (80 km) long, in south central Montana in the United States. It rises in the Gallatin National Forest, in the Crazy Mountains in eastern Park County. It flows northeast, into Sweet Grass County, then southeast, past Melville, and south, joining the Yellowstone 2 mi (3 km) northwest of Greycliff. Variant names Sweet Grass Creek has also been known as: Otter River. See also *List of rivers of Montana *Montana Stream Access Law The Montana Stream Access Law says that anglers, floaters and other recreationists in Montana have full use of most natural waterways between the high-water marks for fishing and floating, along with swimming and other river or stream-related act ... Notes Rivers of Montana Rivers of Park County, Montana Bodies of water of Sweet Grass County, Montana Tributaries of the Yellowstone River {{Montana-river-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Fork Musselshell River
The South Fork Musselshell River is a tributary of the Musselshell River in south central Montana in the United States. It rises in the Lewis and Clark National Forest in the Crazy Mountains in southern Meagher County. It flows northeast, joining the North Fork to form the Musselshell near Martinsdale just west of county line with Wheatland County. See also *List of rivers of Montana *Montana Stream Access Law The Montana Stream Access Law says that anglers, floaters and other recreationists in Montana have full use of most natural waterways between the high-water marks for fishing and floating, along with swimming and other river or stream-related act ... Rivers of Montana Rivers of Meagher County, Montana {{Montana-river-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shields River
The Shields River is a tributary of the Yellowstone River, long, in Meagher and Park Counties Montana in the United States. It rises in the Gallatin National Forest in the Crazy Mountains in northern Park County. It flows west, then south, between the Bridger Range to the west and the Crazy Mountains to the east, past Wilsall and Clyde Park. It joins the Yellowstone approximately 10 mi (16 km) northeast of Livingston. The Shields River was named for John Shields (explorer), a member of the Lewis and Clark Expedition.Gannett, Henry,"The origin of certain place names in the United States", Google eBook. The river hosts native Yellowstone cutthroat trout and Mountain whitefish as well as introduced brown and rainbow trout. See also *List of rivers of Montana *Montana Stream Access Law The Montana Stream Access Law says that anglers, floaters and other recreationists in Montana have full use of most natural waterways between the high-water marks for fishing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sill (geology)
In geology, a sill is a tabular sheet intrusion that has intruded between older layers of sedimentary rock, beds of volcanic lava or tuff, or along the direction of foliation in metamorphic rock. A ''sill'' is a ''concordant intrusive sheet'', meaning that a sill does not cut across preexisting rock beds. Stacking of sills builds a sill complex . and a large magma chamber at high magma flux. In contrast, a dike is a discordant intrusive sheet, which does cut across older rocks. Sills are fed by dikes, except in unusual locations where they form in nearly vertical beds attached directly to a magma source. The rocks must be brittle and fracture to create the planes along which the magma intrudes the parent rock bodies, whether this occurs along preexisting planes between sedimentary or volcanic beds or weakened planes related to foliation in metamorphic rock. These planes or weakened areas allow the intrusion of a thin sheet-like body of magma paralleling the existing bedding pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dike (geology)
A dike or dyke, in Geology, geological usage, is a sheet of rock that is formed in a Fracture (geology), fracture of a pre-existing rock body. Dikes can be either Intrusive rock, magmatic or Sedimentary rock, sedimentary in origin. Magmatic dikes form when magma flows into a crack then solidifies as a sheet intrusion, either cutting across layers of rock or through a contiguous mass of rock. Clastic dikes are formed when sediment fills a pre-existing crack.Essentials of Geology, 3rd Ed, Stephen Marshak Magmatic dikes A magmatic dike is a sheet of igneous rock that cuts across older rock beds. It is formed when magma fills a fracture in the older beds and then cools and solidifies. The dike rock is usually more resistant to weathering than the surrounding rock, so that erosion exposes the dike as a natural wall or ridge. It is from these natural walls that dikes get their name. Dikes preserve a record of the fissures through which most mafic magma (fluid magma low in silica) reac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gabbro
Gabbro () is a phaneritic (coarse-grained), mafic intrusive igneous rock formed from the slow cooling of magnesium-rich and iron-rich magma into a holocrystalline mass deep beneath the Earth's surface. Slow-cooling, coarse-grained gabbro is chemically equivalent to rapid-cooling, fine-grained basalt. Much of the Earth's oceanic crust is made of gabbro, formed at mid-ocean ridges. Gabbro is also found as plutons associated with continental volcanism. Due to its variant nature, the term ''gabbro'' may be applied loosely to a wide range of intrusive rocks, many of which are merely "gabbroic". By rough analogy, gabbro is to basalt as granite is to rhyolite. Etymology The term "gabbro" was used in the 1760s to name a set of rock types that were found in the ophiolites of the Apennine Mountains in Italy. It was named after Gabbro, a hamlet near Rosignano Marittimo in Tuscany. Then, in 1809, the German geologist Christian Leopold von Buch used the term more restrictively in his descri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diorite
Diorite ( ) is an intrusive igneous rock formed by the slow cooling underground of magma (molten rock) that has a moderate content of silica and a relatively low content of alkali metals. It is intermediate in composition between low-silica (mafic) gabbro and high-silica ( felsic) granite. Diorite is found in mountain-building belts (''orogens'') on the margins of continents. It has the same composition as the fine-grained volcanic rock, andesite, which is also common in orogens. Diorite has been used since prehistoric times as decorative stone. It was used by the Akkadian Empire of Sargon of Akkad for funerary sculptures, and by many later civilizations for sculptures and building stone. Description Diorite is an intrusive igneous rock composed principally of the silicate minerals plagioclase feldspar (typically andesine), biotite, hornblende, and sometimes pyroxene. The chemical composition of diorite is intermediate, between that of mafic gabbro and felsic grani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start of the Cenozoic Era, and extended to the beginning of the Quaternary glaciation at the end of the Pliocene Epoch. The time span covered by the Tertiary has no exact equivalent in the current geologic time system, but it is essentially the merged Paleogene and Neogene periods, which are informally called the Early Tertiary and the Late Tertiary, respectively. The Tertiary established the Antarctic as an icy island continent. Historical use of the term The term Tertiary was first used by Giovanni Arduino during the mid-18th century. He classified geologic time into primitive (or primary), secondary, and tertiary periods based on observations of geology in Northern Italy. Later a fourth period, the Quaternary, was applied. In the early d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
