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Glauconite
Glauconite is an iron potassium phyllosilicate ( mica group) mineral of characteristic green color which is very friable and has very low weathering resistance. It crystallizes with a monoclinic geometry. Its name is derived from the Greek () meaning 'bluish green', referring to the common blue-green color of the mineral; its sheen ( mica glimmer) and blue-green color. Its color ranges from olive green, black green to bluish green, and yellowish on exposed surfaces due to oxidation. In the Mohs scale it has a hardness of 2, roughly the same as gypsum. The relative specific gravity range is 2.4–2.95. It is normally found as dark green rounded concretions with the dimensions of a sand grain. It can be confused with chlorite (also of green color) or with a clay mineral. Glauconite has the chemical formula . Glauconite particles are one of the main components of greensand, glauconitic siltstone and glauconitic sandstone. Glauconite has been called a marl in an old and br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glauconitic Sandstone
Greensand or green sand is a sand or sandstone which has a greenish color. This term is specifically applied to shallow marine sediment that contains noticeable quantities of rounded greenish grains. These grains are called ''glauconies'' and consist of a mixture of mixed-layer clay minerals, such as smectite and glauconite. Greensand is also loosely applied to any glauconitic sediment. Formation Greensand forms in anoxic marine environments that are rich in organic detritus and low in sedimentary input. Having accumulated in marine environments, greensands can be fossil-rich, such as in the late-Cretaceous deposits of New Jersey, United States. Occurrence Important exposures are known from both northern and western Europe, North America, southeastern Brazil and north Africa. Well known and important greensands are the Upper and Lower Greensands of England and occur within Eocene and Cretaceous sedimentary strata underlying the coastal plains of New Jersey and Delaware in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mannville Group
The Mannville Group is a stratigraphic unit of Cretaceous age in the Western Canadian Sedimentary Basin. It takes the name from the town of Mannville, Alberta, and was first described in the ''Northwest Mannville 1'' well by A.W. Nauss in 1945. Lithology The Mannville Group consists of interbedded continental sand and shale in the base, followed by a calcareous sandstone member, marine shale, glauconitic sandstone and salt and pepper sandstone. An additional non-marine sequence is present in north-eastern Alberta. Hydrocarbon production Bitumen is produced from the McMurray Formation at the Athabasca Oil Sands. Heavy Oil is produced from the Wabiskaw Member of the Clearwater Formation in the Wabasca oil field, and from multiple formations in the Lloydminster and Provost areas in eastern Alberta and western Saskatchewan. Natural gas is extracted from the Ostracod and Glauconite beds in southern Alberta, and light oil is extracted from the Ellerslie Member in central an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Authigenic
Authigenesis is the process whereby a mineral or sedimentary rock deposit is generated where it is found or observed. Such deposits are described as authigenic. Authigenic sedimentary Mineral, minerals form during or after sedimentation by Precipitation (chemistry), precipitation or Recrystallization (geology), recrystallization as opposed to detrital minerals, which are weathered by water or wind and transported to the depositional location. Authigenic sediments are the main constituents of deep sea sedimentation, compared to shallow waters or land where detrital sediments are more common. Authigenesis process The authigenesis process is driven by particles of sediment that are not in thermodynamic equilibrium with the conditions surrounding it. This often occurs in the ocean where changing conditions due to biological processes is common. In water, changing oxygen content or changing saturation causes Precipitation (chemistry), precipitation of minerals into the sediments, chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marl
Marl is an earthy material rich in carbonate minerals, Clay minerals, clays, and silt. When Lithification, hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. Marl makes up the lower part of the White cliffs of Dover, cliffs of Dover, and the Channel Tunnel follows these marl layers between France and the United Kingdom. Marl is also a common sediment in post-glacial lakes, such as the marl ponds of the northeastern United States. Marl has been used as a soil conditioner and neutralizing agent for acid soil and in the manufacture of cement. Description Marl or marlstone is a carbonate mineral, carbonate-rich mud or mudstone which contains variable amounts of Clay minerals, clays and silt. The term was originally loosely applied to a variety of materials, most of which occur as loose, earthy deposits consisting chiefly of an intimate mixture of clay and calcium carbonate, formed under freshwa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of soil or soil type; i.e., a soil containing more than 85 percent sand-sized particles by mass. The composition of sand varies, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica (silicon dioxide, or SiO2), usually in the form of quartz. Calcium carbonate is the second most common type of sand. One such example of this is aragonite, which has been created over the past 500million years by various forms of life, such as coral and shellfish. It is the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years, as in the Caribbean. Somewhat more rarely, sand may be composed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glauconitic Marl
The Chalk Group (often just called the Chalk) is the lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England. The same or similar rock sequences occur across the wider northwest European chalk 'province'. It is characterised by thick deposits of chalk, a soft porous white limestone, deposited in a marine environment. Chalk is a limestone that consists of coccolith biomicrite. A biomicrite is a limestone composed of fossil debris ("bio") and calcium carbonate mud ("micrite"). Most of the fossil debris in chalk consists of the microscopic plates, which are called coccoliths, of microscopic green algae known as coccolithophores. In addition to the coccoliths, the fossil debris includes a variable, but minor, percentage of the fragments of foraminifera, ostracods and mollusks. The coccolithophores lived in the upper part of the water column. When they died, the microscopic calcium carbonate pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllosilicate
Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, the crystalline forms of silica (silicon dioxide, ) are usually considered to be Silicate mineral#Tectosilicates, tectosilicates, and they are classified as such in the Dana system (75.1). However, the Nickel-Strunz system classifies them as oxide minerals (4.DA). Silica is found in nature as the mineral quartz, and its polymorphism (materials science), polymorphs. On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis. Living organisms also contribute to this carbonate–silicate cycle, geologic cycle. For example, a type of plankton ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Gravity
Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for solids and liquids is nearly always measured with respect to water at its densest (at ); for gases, the reference is air at room temperature (). The term "relative density" (abbreviated r.d. or RD) is preferred in SI, whereas the term "specific gravity" is gradually being abandoned. If a substance's relative density is less than 1 then it is less dense than the reference; if greater than 1 then it is denser than the reference. If the relative density is exactly 1 then the densities are equal; that is, equal volumes of the two substances have the same mass. If the reference material is water, then a substance with a relative density (or specific gravity) less than 1 will float in water. For example, an ice cube, with a relative density of about 0.91, will float. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continental Shelf
A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an island is known as an "''insular shelf''." The continental margin, between the continental shelf and the abyssal plain, comprises a steep continental slope, surrounded by the flatter continental rise, in which sediment from the continent above cascades down the slope and accumulates as a pile of sediment at the base of the slope. Extending as far as 500 km (310 mi) from the slope, it consists of thick sediments deposited by turbidity currents from the shelf and slope. The continental rise's gradient is intermediate between the gradients of the slope and the shelf. Under the United Nations Convention on the Law of the Sea, the name continental shelf was given a legal definition as the stretch of the seabed adjacent to the shores ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Western Canada
Western Canada, also referred to as the Western provinces, Canadian West, or Western provinces of Canada, and commonly known within Canada as the West, is a list of regions of Canada, Canadian region that includes the four western provinces and territories of Canada, provinces just north of the Canada–United States border namely (from west to east) British Columbia, Alberta, Saskatchewan and Manitoba. The people of the region are often referred to as "Western Canadians" or "Westerners", and though diverse from province to province are largely seen as being collectively distinct from other Canadians along cultural, linguistic, socioeconomic, geographic and political lines. They account for approximately 32% of Canada's total population. The region is further subdivided geographically and culturally between British Columbia, which is mostly on the western side of the Canadian Rockies and often referred to as the "British Columbia Coast, west coast", and the "Prairie Provinces" (c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Word Sense
In linguistics, a word sense is one of the meanings of a word. For example, a dictionary may have over 50 different senses of the word "play", each of these having a different meaning based on the context of the word's usage in a sentence, as follows: In each sentence different collocates of "play" signal its different meanings. People and computers, as they read words, must use a process called word-sense disambiguationR. Navigli''Word Sense Disambiguation: A Survey'' ACM Computing Surveys, 41(2), 2009, pp. 1-69. to reconstruct the likely intended meaning of a word. This process uses context to narrow the possible senses down to the probable ones. The context includes such things as the ideas conveyed by adjacent words and nearby phrases, the known or probable purpose and register of the conversation or document, and the orientation (time and place) implied or expressed. The disambiguation is thus context-sensitive. Advanced semantic analysis has resulted in a sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
