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Pioneer Creek
Pioneer Creek is a tributary of Baker Creek in the U.S. state of Alaska. Other Baker tributaries in the vicinity include Eureka, Thanksgiving, and Gold Run. Geography Pioneer Creek heads against the Baker- Minook divide, flows around the head of the Eureka, and then, at a distance of , flows parallel to the main course of that creek. After traversing , it joins Eureka Creek and they are said to lose themselves on Baker Flats. Pioneer Creek never carries less than three or four sluice-heads of water, and its gradient along its lower course is about per mile. The valley's northwest side has a gentle slope running back for about a mile, and the southeast side is of almost precipitous steepness. On the gentle slope of the northwest side there are perceptibly flatter places or benches, but only one of these is persistent. This bench is traceable along Pioneer Creek for over . Its northeast end is a little above the present level of the creek while its southwest end is about above the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tributary
A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage basin of its surface water and groundwater, leading the water out into an ocean. The Irtysh is a chief tributary of the Ob river and is also the longest tributary river in the world with a length of . The Madeira River is the largest tributary river by volume in the world with an average discharge of . A confluence, where two or more bodies of water meet, usually refers to the joining of tributaries. The opposite to a tributary is a distributary, a river or stream that branches off from and flows away from the main stream. PhysicalGeography.net, Michael Pidwirny & S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baker Creek (Alaska)
Baker Creek is a right bank tributary of the Tanana River in the U.S. state of Alaska. Baker Creek tributaries include Thanksgiving, Gold Run, Eureka, and Pioneer creeks; Seattle Junior Creek is a tributary of Pioneer Creek. The Baker Creek diggings of the early 20th century were situated approximately south of Rampart. Geography The creek flows along the southwestern side of a large flat, broad in its widest part, and approximately long. Its longer extensions are northeast–southwest in the line of flow of Eureka and Hutlina creeks. Instead of sharp canyon-like valleys, the streams flow through open valleys, and where they flow in general parallel to the Baker- Minook divide—that is, approaching a northeast–southwest or an east–west direction—the southern bank is steep, while the northern one is gently sloping, the creeks flowing close to the steeper side. Even along the broad Baker Flats, this feature is still prominent. The north side is a long gentle slope toward the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., it borders the Canadian province of British Columbia and the Yukon territory to the east; it also shares a maritime border with the Russian Federation's Chukotka Autonomous Okrug to the west, just across the Bering Strait. To the north are the Chukchi and Beaufort Seas of the Arctic Ocean, while the Pacific Ocean lies to the south and southwest. Alaska is by far the largest U.S. state by area, comprising more total area than the next three largest states (Texas, California, and Montana) combined. It represents the seventh-largest subnational division in the world. It is the third-least populous and the most sparsely populated state, but by far the continent's most populous territory located mostly north of the 60th parallel, with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eureka Creek
Eureka Creek is a tributary of Baker Creek in the U.S. state of Alaska. Other Baker tributaries in the vicinity of Eureka Creek include Thanksgiving, Gold Run, and Pioneer creeks with Seattle Junior Creek a tributary of Pioneer. Geography Eureka Creek flows southwest along the foot of the Baker- Minook divide. It runs in a straight southwest course for about , then turns and runs south to its junction with Pioneer Creek. It has a number of small tributaries from the northwest side, but none from the southeast. The largest is Boston Creek, about long, which joins Eureka Creek at its bend. The other tributaries are rill In hillslope geomorphology, a rill is a shallow channel (no more than a few inches/ decimeters deep) cut into soil by the erosive action of flowing surface water. Similar but smaller incised channels are known as microrills; larger incised c ...s. Eureka is a small creek carrying barely a sluicehead of water above the mouth of Boston Creek during the ordinar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minook Creek
Minook Creek (variation Mynook Creek; native name, ''Klanarkakat'', meaning "creek suitable for small boats") is a waterway in the U.S. state of Alaska. It is named after John Mynook Pavaloff, a half-Russian/half-native Alaskan, who found gold in the river's valley in 1894. Geography Minook Creek empties into the Yukon River just east of Rampart Rampart may refer to: * Rampart (fortification), a defensive wall or bank around a castle, fort or settlement Rampart may also refer to: * "O'er the Ramparts We Watched" is a key line from "The Star-Spangled Banner", the national anthem of the .... It is about long. Near its mouth, it is a shallow stream wide. It flows in a northerly direction through a deep valley whose width varies from a few hundred feet to about a half mile. The creek receives a number of large tributaries from the east— Hunter, Little Minook, Little Minook Junior, Hoosier, Florida, Chapman—and a number of others. From the west, it receives Montana, Ruby, Slat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sluice
Sluice ( ) is a word for a channel controlled at its head by a movable gate which is called a sluice gate. A sluice gate is traditionally a wood or metal barrier sliding in grooves that are set in the sides of the waterway and can be considered as a bottom opening in a wall. Sluice gates are one of the most common hydraulic structures in controlling flow rate and water level in open channels such as rivers and canals. They also could be used to measure the flow. A water channel containing a sluice gate forms a type of lock to manage the water flow and water level. It can also be an open channel which processes material, such as a River Sluice used in gold prospecting or fossicking. A mill race, leet, flume, penstock or lade is a sluice channeling water toward a water mill. The terms sluice, sluice gate, knife gate, and slide gate are used interchangeably in the water and wastewater control industry. They are also used in wastewater treatment plants and to recover minerals in minin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bar (river Morphology)
A bar in a river is an elevated region of sediment (such as sand or gravel) that has been deposited by the flow. Types of bars include mid-channel bars (also called braid bars and common in braided rivers), point bars (common in meandering rivers), and mouth bars (common in river deltas). The locations of bars are determined by the geometry of the river and the flow through it. Bars reflect sediment supply conditions, and can show where sediment supply rate is greater than the transport capacity. A mid-channel bar, is also often referred to as a braid bar because they are often found in braided river channels. Braided river channels are broad and shallow and found in areas where sediment is easily eroded like at a glacial outwash, or at a mountain front with high sediment loads. These types of river systems are associated with high slope, sediment supply, stream power, shear stress, and bed load transport rates. Braided rivers have complex and unpredictable channel patt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schist
Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. 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 micas, 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 schist''). Where the type of the original rock (the protolith) is discernible, the schist is us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slate
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. It is the finest grained foliated metamorphic rock. Foliation may not correspond to the original sedimentary layering, but instead is in planes perpendicular to the direction of metamorphic compression. The foliation in slate is called "slaty cleavage". It is caused by strong compression causing fine grained clay flakes to regrow in planes perpendicular to the compression. When expertly "cut" by striking parallel to the foliation, with a specialized tool in the quarry, many slates will display a property called fissility, forming smooth flat sheets of stone which have long been used for roofing, floor tiles, and other purposes. Slate is frequently grey in color, especially when seen, en masse, covering roofs. However, slate occurs in a variety of colors even from a single locality; for ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartzite
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones. Since antiquity, varieties of quartz have been the most commonly used minerals in the making of jewelry and hardstone carvings, especially in Eurasia. Quartz is the mineral defining the val ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrite
The mineral pyrite (), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Iron, FeSulfur, S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic Luster (mineralogy), luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of ''fool's gold''. The color has also led to the nicknames ''brass'', ''brazzle'', and ''Brazil'', primarily used to refer to pyrite found in coal. The name ''pyrite'' is derived from the Greek language, Greek (), 'stone or mineral which strikes fire', in turn from (), 'fire'. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what we now call pyrite. By Georgius Agricola's time, , the term had become a generic term for all of the pyrite group, sulfide minerals. Pyrite is usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
