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Macerals
A maceral is a component, organic in origin, of coal or oil shale. The term 'maceral' in reference to coal is analogous to the use of the term 'mineral' in reference to igneous or metamorphic rock, metamorphic rocks. Examples of macerals are inertinite, vitrinite, and Exinite, liptinite. Inertinite Inertinite is considered to be the equivalent of charcoal and degraded plant material. It is highly oxidised in nature and may be said to be burnt. A large portion of South Africa's coal reserves consist of inertinite. Vitrinite Vitrinite is shiny, glass-like material that is considered to be composed of cellular plant material such as roots, bark, plant stems and tree trunks. Vitrinite macerals when observed under the microscope show a boxlike, cellular structure, often with oblong voids and cavities which are likely the remains of plant stems. This has a high calorific value (24 - 28 MJ/kg) and a large proportion of volatile matter (24 - 30%). It often occurs interbanded or i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Funginite (maceral)
Funginite is a maceral, a component, organic in origin, of coal or oil shale, exhibiting several different physical properties and characteristics under particular conditions; its dimensions are based upon its source and place of discovery. Furthermore, it is primarily part of a group of macerals that naturally occur in rocks containing mostly carbon constituents, specifically coal. Due to its nature, research into the chemical structure and formula of funginite is considered limited and lacking. According to Chen et al. referencing ICCP, 2001 (International Committee for Coal and Organic Petrology), alongside the maceral secretinite, they "are both macerals of the inertinite group, which is more commonly known as fossilized charcoal, and were previously jointly classified as the maceral sclerotinite". In the scientific community, the discernment between the two does not remain entirely clear, but there are slight particular and specific differences in regards to the composition betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerogen
Kerogen is solid, insoluble organic matter in sedimentary rocks. It consists of a variety of organic materials, including dead plants, algae, and other microorganisms, that have been compressed and heated by geological processes. All the kerogen on earth is estimated to contain 1016 tons of carbon. This makes it the most abundant source of organic compounds on earth, exceeding the total organic content of living matter 10,000-fold. The type of kerogen present in a particular rock formation depends on the type of organic material that was originally present. Kerogen can be classified by these origins: lacustrine (e.g., algal), marine (e.g., planktonic), and terrestrial (e.g., pollen and spores). The type of kerogen depends also on the degree of heat and pressure it has been subjected to, and the length of time the geological processes ran. The result is that a complex mixture of organic compounds resides in sedimentary rocks, serving as the precursor for the formation of hyd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inertinite
Inertinites are a group of partially oxidized organic (mainly plant) materials or fossilized charcoals, all sharing the characteristic that they typically are inert (i.e., not altered) when heated in the absence of oxygen. Inertinite is a common maceral in most types of coal. The main inertinite submacerals are fusinite, semifusinite, micrinite, macrinite, and funginite, with semifusinite being the most common. From the perspective of coal combustion, inertinite can be burned to yield heat but does not yield significant volatile fractions during coking. Inertinite is also found as tiny flakes within sedimentary rocks. The presence of inertinite in this context is significant in the geological record, as it signifies that wildfires may have occurred at the time that the host sediment was deposited. It can also be an indication of oxidation due to atmospheric exposure or fungal decomposition during deposition. The optical properties of semifusinite are very similar to those of vit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exinite
In coal geology, liptinite is the finely-ground and macerated remains found in coal deposits. It replaced the term exinite as one of the four categories of kerogen. Liptinites were originally formed by spores, pollen, dinoflagellate cysts, leaf cuticles, and plant resins and waxes.Taylor et al., 1998. Organic Petrography. Gebrüder Borntraeger, Berlin. pp. 176 M.C. Stopes introduced the term ''exinite'' in 1935 to describe the microscopic constituent of coal, rich in volatiles and relatively rich in hydrogen, that is represented by the exines of spores. C.A. Seyler in 1932, however, used the term with its present meaning, designating the following group of macerals: sporinite, cutinite, alginite (telalginite and lamalginite), resinite. Macerals A maceral is a component, organic in origin, of coal or oil shale. The term 'maceral' in reference to coal is analogous to the use of the term 'mineral' in reference to igneous or metamorphic rock, metamorphic rocks. Examples of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitrinite
Vitrinite is one of the primary components of coals and most sedimentary kerogens. Vitrinite is a type of maceral, where "macerals" are organic components of coal analogous to the "minerals" of rocks. Vitrinite has a shiny appearance resembling glass (vitreous). It is derived from the cell-wall material or woody tissue of the plants from which coal was formed. Chemically, it is composed of polymers, cellulose and lignin. Vitrinite Reflectance (Ro%) : Vitrinite reflectance (Ro%) is a very important geochemical parameter used to assess and evaluate the thermal maturity of sedimentary rocks, particularly those rich in organic matter. It is measure of the reflectivity of vitrinite—a type of maceral (organic component of coal and sedimentary rock)—when viewed under a microscope using oil immersion and reflected light.It is expressed as a percentage (Ro%), vitrinite reflectance increases with greater burial depth and thermal exposure, making it a reliable indicator of the maximum te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutinite group of Macerals derived from waxy outer coating of leaves, roots, and stems. Cutinite is Hydrogen rich and it fluoresces under UV light.
Reference: https://web.archive.org/web/20110720044325/http://mccoy.lib.siu.edu/projects/crelling2/atlas/macerals/mactut.html ...
Cutinite is a liptinite maceral formed from terrestrial plant cuticles, and often found in coal deposits. It is classified as a Type II kerogen. References Coal Petrology {{petrology-stub Cutinite is a coal maceral of Liptinite In coal geology, liptinite is the finely-ground and macerated remains found in coal deposits. It replaced the term exinite as one of the four categories of kerogen. Liptinites were originally formed by spores, pollen, dinoflagellate cysts, leaf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal
Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is a type of fossil fuel, formed when dead plant matter decays into peat which is converted into coal by the heat and pressure of deep burial over millions of years. Vast deposits of coal originate in former wetlands called coal forests that covered much of the Earth's tropical land areas during the late Carboniferous (Pennsylvanian (geology), Pennsylvanian) and Permian times. Coal is used primarily as a fuel. While coal has been known and used for thousands of years, its usage was limited until the Industrial Revolution. With the invention of the steam engine, coal consumption increased. In 2020, coal supplied about a quarter of the world's primary energy and over a third of its Electricity generation, electricity. Some iron and steel-maki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporinite
Sporinite is a kind of exinite maceral found in coal formed from spores and pollen. It is a Type II kerogen Kerogen is solid, insoluble organic matter in sedimentary rocks. It consists of a variety of organic materials, including dead plants, algae, and other microorganisms, that have been compressed and heated by geological processes. All the kero .... References {{petrology-stub Coal Petrology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bituminite
Bituminite is an autochthonous maceral that is a part of the liptinite group in lignite, that occurs in petroleum source rocks originating from organic matter such as algae which has undergone alteration or degradation from natural processes such as burial . It occurs as fine-grained groundmass, laminae or elongated structures that appear as veinlets within horizontal sections of lignite and bituminous coals, and also occurs in sedimentary rocks. Its occurrence in sedimentary rocks is typically found surrounding alginite, and parallel along bedding planes. Bituminite is not considered to be bitumen because its properties are different from most bitumens. It is described to have no definite shape or form when present in bedding and can be identified using different kinds of visible and fluorescent lights. There are three types of bituminite: type I, type II and type III, of which type I is the most common. The presence of bituminite in oil shales, other oil source rocks and some coa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bituminous Coal
Bituminous coal, or black coal, is a type of coal containing a tar-like substance called bitumen or asphalt. Its coloration can be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the coal seam, seams. It is typically hard but friable. Its quality is Coal analysis#Coal classification by rank, ranked higher than lignite and sub-bituminous coal, but lesser than anthracite. It is the most abundant rank of coal, with deposits found around the world, often in rocks of Carboniferous age. Bituminous coal is formed from sub-bituminous coal that is buried deeply enough to be heated to or higher. Bituminous coal is used primarily for electrical power generation and in the steel industry. Bituminous coal suitable for smelting iron (''coking coal'' or ''metallurgical coal'') must be low in sulfur and phosphorus. It commands a higher price than other grades of bituminous coal (thermal coal) used for heating and power generation. Within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spores
In biology, a spore is a unit of sexual (in fungi) or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, fungi and protozoa. They were thought to have appeared as early as the mid-late Ordovician period as an adaptation of early land plants. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. In some rare cases, a diploid spore is also produced in some algae, or fungi. Under favourable conditions, the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lignite
Lignite (derived from Latin ''lignum'' meaning 'wood'), often referred to as brown coal, is a soft, brown, combustible sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35% and is considered the lowest rank of coal due to its relatively low heat content. When removed from the ground, it contains a very high amount of moisture, which partially explains its low carbon content. Lignite is mined all around the world and is used almost exclusively as a fuel for steam-electric power generation. Lignite combustion produces less heat for the amount of carbon dioxide and sulfur released than other ranks of coal. As a result, lignite is the most harmful coal to human health. Depending on the source, various toxic heavy metals, including naturally occurring radioactive materials, may be present in lignite and left over in the coal fly ash produced from its combustion, further increasing health risks. Characteristics Lignite is brownish-bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
