POSC Specifications
Version 2.2 		Epicentre Standard Values
material_class

material_class

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 Standard Instance Values

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name classification _system description source version status
  classification _system .name   ref _source .name ref _epicentre _version .name  
supergroup lithostratigraphic unit A lithostratigraphic unit, ranking above group, that identifies a group of contiguous formations and groups having some unifying characteristic. POSC 2.2 provisional
group lithostratigraphic unit The lithostratigraphic rank above formation, comprising a sequence of contiguous associated formations with significant unifying lithologic features. POSC 2.2 provisional
formation lithostratigraphic unit The primary formal unit of lithostratigraphic classification. It is intermediate in rank and is informally defined as a mappable rock body characterized by a distinctive lithology. POSC 2.2 provisional
member lithostratigraphic unit Member is the lithostratigraphic rank below formation, characterized by a distinctive lithology within a formation. POSC 2.2 provisional
bed lithostratigraphic unit The lowest ranking unit of lithostratigraphic classification, a bed is a lithologically distinctive rock body within a member or formation. POSC 2.2 provisional
abundance zone biostratigraphic unit A biozone characterized by quantitatively distinctive maxima of relative abundance of one or more taxa. It is essentially the same as acme zone. POSC 2.2 provisional
interval zone biostratigraphic unit The biozone between two specified, documented lowest and/or highest occurrences of single taxa. Three basic types are recognized: taxon range zone, concurrent range zone, and lineage zone. POSC 2.2 provisional
taxon range zone biostratigraphic unit The interval zone between the documented lowest and highest occurrences of a single taxon. POSC 2.2 provisional
concurrent range zone biostratigraphic unit The interval zone included between the documented lowest occurrence of one taxon and the documented highest occurrence of another taxon, resulting in stratigraphic overlap of the two taxa. POSC 2.2 provisional
lineage zone biostratigraphic unit The interval zone between successive documented lowest occurrences within an evolutionalry lineage. POSC 2.2 provisional
assemblage zone biostratigraphic unit A biozone characterized by the association of three or more taxa. It may be based on all kinds of fossils present, or restricted to only certain kinds of fossils. It may consist of a geographically or stratigraphically restricted assemblage, or may incorporate two or more contemporaneous assemblages with shared characteristic taxa. The assemblage zone is named from one or more of the fossils particularly representative of the assemblage. POSC 2.2 provisional
eonothem chronostratigraphic unit The highest ranking unit of chronostratigraphic classification. Eonothem is comprised of the strata deposited during a geochronologic eon. POSC 2.2 provisional
erathem chronostratigraphic unit The second highest ranking unit of classification of chronostratigraphic systems. Erathem corresponds to the strata deposited during a geochronologic era. POSC 2.2 provisional
system chronostratigraphic unit The third highest ranking unit of chronostratigraphic classification. A system corresponds to the strata deposited during a geochronologic period. POSC 2.2 provisional
series chronostratigraphic unit A minor ranking unit of chronostratigraphic classification; a series corresponds to the strata deposited during a geochronologic epoch. POSC 2.2 provisional
stage chronostratigraphic unit A minor ranking unit of chronostratigraphic classification; a series corresponds to the strata deposited during a geochronologic epoch. POSC 2.2 provisional
substage chronostratigraphic unit An informal, minor ranking unit of chronostratigraphic classification; a substage is a subdivision of a stage, characterized by some unifying characteristic. POSC 2.2 provisional
megasequence sequence stratigraphic unit A rock body, characterized by its position within an historical model of sedimentary depositional systems. Megasequences contain sequences. POSC 2.2 provisional
sequence sequence stratigraphic unit A body of rock that is unified by their relatively conformable depositonal succession and bounded at the top and base by unconformities or their correlative conformities. POSC 2.2 provisional

material_class

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name classification _system description source version status
boulder grain size Grain size greater than 256 mm. POSC 2.1 current
cobble grain size Grain size bigger than 64 mm and smaller than 256 mm. POSC 2.1 current
pebble grain size Grain size bigger than 4 mm and smaller than 64 mm. POSC 2.1 current
granule grain size Grain size bigger than 2 mm and smaller than 4 mm. POSC 2.1 current
very coarse sand grain size Grain size bigger than 1 mm and smaller than 2 mm. POSC 2.1 current
coarse sand grain size Grain size bigger than .5 mm and smaller than 1 mm. POSC 2.1 current
medium sand grain size Grain size bigger than .25 mm and smaller than .5 mm. POSC 2.1 current
fine sand grain size Grain size bigger than .125 mm and smaller than .25 mm. POSC 2.1 current
very fine sand grain size Grain size bigger than .062 mm and smaller than .125 mm. POSC 2.1 current
silt grain size Grain size bigger than .020 mm and smaller than .062 mm. POSC 2.1 current
mudstone carbonate texture Dunham Depositional texture is recognizable, the original components were not bound together during deposition, with mud support of the carbonate grains and less than 10% carbonate grains total. POSC 2.1 current
wackestone carbonate texture Dunham Depositional texture is recognizable, the original components were not bound together during deposition, with mud support of the carbonate grains and more than 10% carbonate grains total. POSC 2.1 current
packstone carbonate texture Dunham Depositional texture is recognizable, the original components were not bound together during deposition, with grain support of the carbonate grains and an observable fraction of mud. POSC 2.1 current
grainstone carbonate texture Dunham Depositional texture is recognizable, the original components were not bound together during deposition, with grain support of the carbonate grains and no observable fraction of mud. POSC 2.1 current
boundstone carbonate texture Dunham Depositional texture is recognizable and the original components were bound together during deposition. POSC 2.1 current
crystalline carbonate texture Dunham Depositional texture is not recognizable. POSC 2.1 current
micrite carbonate type Folk A semiopaque crystalline matrix of limestone. A limestone classified as micrite has crystals less than 4 microns in size. There is no genetic implication. POSC 2.1 current
dismicrite carbonate type Folk A fine-textured limestone with less than 1% allochems, consisting mainly of lithified carbonate mud. POSC 2.1 current
sparry allochemical limestone carbonate type Folk A limestone with sparry calcite cement more abundant than micritic cement and allochems greater than 1%. POSC 2.1 current
micritic allochemical limestone carbonate type Folk A limestone with micritic cement more abundant than sparry calcite cement, and allochems greater than 1%. POSC 2.1 current

material_class

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name classification _system description source version status
biolithite carbonate type Folk A limestone constructed by organisms that grew and remained in place, characterized by a rigid framework of carbonate material that binds allochem grains and skeletal elements. POSC 2.1 current
intrasparite carbonate type Folk A sparry allochemical limestone in which the grains are predominantly intraclasts. POSC 2.1 current
oosparite carbonate type Folk A sparry allochemical limestone in which the grains are predominantly ooids. POSC 2.1 current
biosparite carbonate type Folk A sparry allochemical limestone in which the grains are predominantly skeletal grains. POSC 2.1 current
pelsparite carbonate type Folk A sparry allochemical limestone in which the grains are predominantly peloids POSC 2.1 current
intramicrite carbonate type Folk A micritic allochemical limestone in which the grains are predominantly intraclasts. POSC 2.1 current
oomicrite carbonate type Folk A micritic allochemical limestone in which the grains are predominantly ooids. POSC 2.1 current
biomicrite carbonate type Folk A micritic allochemical limestone in which the grains are predominantly skeletal grains. POSC 2.1 current
pelmicrite carbonate type Folk A micritic allochemical limestone in which the grains are predominantly peloids POSC 2.1 current
non-skeletal grain carbonate grain type A carbonate grain that is not obviously derived from the skeletal material of micro-organisms, invertebrates, or the thalli of calcareous plants. POSC 2.1 current
coated grain carbonate grain type non-skeletal carbonate grains that evidence a one or more series of coatings around a central core. Includes ooids, pisoids, and oncoids. POSC 2.1 current
ooid carbonate grain type A coated grain with a calcareous cortex and a nucleus which is variable in composition. The cortex is smoothly and evenly laminated eqpecially in its outer parts. They are typically sphecical or ellipsoidal in shape. Obvious biogenetic structures are lacking. Classification as an ooid is indicative, but is not meant to imply, abiogenic origin. An ooid is less than 2mm in size. POSC 2.1 current
pisoid carbonate grain type A pisoid is applied to a grain that has the characteristics of an ooid, but is > 2 mm in size. POSC 2.1 current
oncoid carbonate grain type A coated grain with a calcareous cortex of irregular, partially overlapping laminae. They are typically irregular in shape. They may exhibit biogenic structures. An oncoid is indicative, but is not meant to imply, biogenic origin. POSC 2.1 current
peloid carbonate grain type A non-sekletal grain, internally structureless, and irregular in shape. A peloid is generally, but not always, of faecal origin. POSC 2.1 current
grain aggregate carbonate grain type An aggregate of several carbonate particles that have become bound and cemented together. Examples are grapestones and lumps. POSC 2.1 current
carbonate clast carbonate grain type Reworked carbonate fragments of at least partly consolidated carbonate sediments. POSC 2.1 current
carbonate intraclast carbonate grain type A carbonate clast that has remained in its original area of deposition POSC 2.1 current
carbonate extraclast carbonate grain type A carbonate clast that is recognizedly removed from its original area of deposition. POSC 2.1 current
skeletal grain carbonate grain type A carbonate grain that is clearly of skeletal origin. Examples are shells, corals, and sponges. The skeletal grain type is often classified by its dominant fossil type. POSC 2.1 current

material_class

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name classification _system description source version status
calcareous algae fossil type A group of algae that precipitate calcium carbonate from the shallow water where they live, and deposit it in a more or less solid carbonate structure. POSC 2.1 current
foraminifera fossil type Protozoans of subclass Sarcodina, order Foraminifera, characterized by the presence of a test of one to many chambers composed of secreted calcite (rarely silica or aragonite) or of agglutinated particles. POSC 2.1 current
sponge fossil type A many-celled invertebrate, phylum Porifera, characterized by an internal skeleton composed most frequently of opaline silica, and less commonly of calcium carbonate. POSC 2.1 current
coelenterate fossil type Any multi-celled invertebrate animal, solitary or colonial, of phylum Coelenterata, characterized by a body wall of two layers of cells connected by a structureless mesoglea, and a single opening for ingesttion and egestion. POSC 2.1 current
stromatoporoid fossil type Any of a group of extinct sessile benthic marine organisms, which secret a calcareous skeleton, generally tens of centimeters across, of tabular, encrusting, dendroidal, domal, or bulbous form. POSC 2.1 current
milleporoid fossil type Any of a group of hydrozoans, order Milleporina, characterized by a calcareous skeleton, and free-swimming sexual individuals. POSC 2.1 current
rugose fossil type Any zoantharian belonging to the order Rugosa, characterized by calcareous corallites that may be solitary and cone-shaped or cylindrical, curved or erect, compound and branching, or massive. POSC 2.1 current
tabulate fossil type Coral characterized by prominent tabulae. POSC 2.1 current
scleractinian fossil type Any zoantharian coelenterate, order Scleractinia, characterized by solitary and colonial forms with calcareous exoskeletons secreted by the ectoderm. POSC 2.1 current
alcyonarian fossil type Any coral, subclass Alcyonaria, colonial forms with eight pinnate tentacles, an endoskeleton, and eight complete septa. POSC 2.1 current
bryozoan fossil type An invertebrate, phylum Bryozoa, characterized chiefly by colonial growth, a calcareous skeleton, and a U-shaped alimentary canal with mouth and anus. POSC 2.1 current
brachiopod fossil type Any solitary marine invertebrate belonging to the phylum Brachiopoda, characterized by a lophophore and by two bilaterally summetrical valves that may be calcareous or chitinase and are commonly attached to a substratum. POSC 2.1 current
mollusk fossil type A solitary invertebrate, phylum Mollusca, characterized by a nonsegmented body that is bilaterally symmetrical and by a radially or biradially symmetrical mantle or shell. POSC 2.1 current
chiton fossil type An invertebrate marine molluscan, the shell of which consists of eight overlapping calcareous valves or plates. POSC 2.1 current
bivalve fossil type Having a shell composed of two distinct and usually movable valves, equal or subequal, that open and shut. POSC 2.1 current
gastropod fossil type Any mollusk, class Gastropoda, characterized by a distinct head with eyes and tentacles and, in most, by a single calcareous shell that is closed at the apex, sometimes spiralled, and generally asymmetrical. E.g., a snail. POSC 2.1 current
pteropod fossil type Belonging to the order Pteropoda, which includes pelagic forms sometimes with shells. The shells are generally conical and composed of aragonite. POSC 2.1 current
cephalopod fossil type An mollusk, class Cephalopoda, characterized by a definite head, with the mouth surrounded by part of the foot, that is modified with tentacles or armlike processes with hooklets or suckers or both. E.g., nautiloids and aminoids. POSC 2.1 current
serpulid fossil type Any annelid, family Serpulidae, that characteristically builds a contorted calcareous or leathery tube on a submerged surface. POSC 2.1 current
arthropod fossil type Any animal of phylum Arthropoda, characterized by jointed appendages and segmented bodies. E.g., trilobites, crabs, crustaceans. POSC 2.1 current

material_class

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name classification _system description source version status
echinoderm fossil type Any solitary marine benthic (rarely pelagic) invertebrate, phylum Echinodermata, characterized by radial symmetry, an endoskeleton formed of plates or ossicles composed of crystalline calcite, and a water vascular system. POSC 2.1 current
matrix carbonate grain type Fine-grained calcite crystals that constitute the matrix of carbonate rocks. POSC 2.1 current
radial coated grain microfabric Fibrous or bladed crystals or aragonite, low magnesium calcite, or high magnesium calcite whose axes are radial to the center. POSC 2.1 current
tangential coated grain microfabric Aragonite or calcite grains whose long axes are parallel to the ooid laminae. POSC 2.1 current
random coated grain microfabric Equant or randomly oriented crystals within the laminae. POSC 2.1 current
cryptocrystalline micrite grain size Crystals from 1 to 4 micrometers. POSC 2.1 current
very finely crystalline micrite grain size Crystals from 4 to 16 micrometers. POSC 2.1 current
finely crystalline micrite grain size Crystals from 16 to 62 micrometers. POSC 2.1 current
medium crystalline micrite grain size Crystals from 62 to 250 micrometers. POSC 2.1 current
coarsely crystalline micrite grain size Crystals from 250 to 1000 micrometers. POSC 2.1 current
very coarsely crystalline micrite grain size Crystals from 1 to 4 millimeters. POSC 2.1 current
extremely coarsely crystalline micrite grain size Crystals greater than 4 millimeters. POSC 2.1 current
1 standard microfacies Spiculite. Dark clayey mudstone or wackestone, organic rich, or siliceous spiculitic calcisiltite. Spicules usually oriented, generally siliceous monaxons, commonly replaced by calcite. The interpreted environment is basinal, deep water. POSC 2.1 current
2 standard microfacies Microbioclastic calcisiltite. Small bioclasts and peloids in very fine-grained grainstone or packstone; small scale ripple cross-lamination. The interpreted environment is open sea shelf near the lower slope, deeper shelf margin. POSC 2.1 current
3 standard microfacies Pelagic mudstone and wackestone. Micritic matrix containing scattered pelagic microfossils or megafauna (e.g. graptolites or thin-shelled bivalve fragments. The interpreted environment is basinal, deep-water or open sea shelf near the lower slope, deeper shelf margin. POSC 2.1 current
4 standard microfacies Microbreccia or bioclastic - lithoclastic packstone. Rounded grains, often graded. Polymict or monomict in origin. Also quartz, cherts, and carbonate detritus. The interpreted environment is fore-slope talus; resedimented limestones. POSC 2.1 current
5 standard microfacies Grainstone - packstone or floatstone with bioclasts of reef. Geopetal sediments. The interpreted environment is reef flank facies. POSC 2.1 current
6 standard microfacies Reef rudstone; no matrix material. The interpreted environment is fore-reef slope, debris from the reef; commonly in high-energy zone. POSC 2.1 current
7 standard microfacies Boundstone. Subtypes of framestone, bindstone, or bafflestone. The interpreted environment is reef, often found on platform margins. POSC 2.1 current
8 standard microfacies Wackestone with whole organisms. Wellppreserved infauna and epifauna. The interpreted environment is shelf lagoon with circulation; low-energy water below normal wavebase. POSC 2.1 current

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name classification _system description source version status
9 standard microfacies Bioclastic wackestone or bioclastic micrite. Fragments of diverse organisms, bioturbated. bioclasts may be micritized. The interpreted environment is shallow waters with open circulation close to wave-base. POSC 2.1 current
10 standard microfacies Packstone - wackestone with coated and abraded bioclasts. The interpreted environment is textural inversion; cominant particles from high-energy environment have moved down local slopes to low-energy settings. POSC 2.1 current
11 standard microfacies Grainstones with coated bioclasts, in sparry cement. The interpreted environment is winnowed platform edge sands; areas with constant wave action at or above wave-base. POSC 2.1 current
12 standard microfacies Coquina, bioclastic packstone, grainstone or rudstone with concentrations of organisms. Certain types of organisms dominate (e.g. dasyclads, sheels, or crinoids. The interpreted environment is slopes and shelf edges. POSC 2.1 current
13 standard microfacies Oncoid (biosparite) grainstone. The interpreted environment is moderately high-energy areas, very shallow water. POSC 2.1 current
14 standard microfacies Lags. Coated with rounded particles, in places mixed with ooids and peloids. May be blackened and iron-stained with phosphate; lithoclasts; usually thin beds. The interpreted environment is slow accumulation of coarse material in zone of winnowing. POSC 2.1 current
15 standard microfacies Oolites of well-sorted ooids; fabric usually overpacked; always cross-bedded. The interpreted environment is high-energy environment on oolite shoals, beaches, and tidal bars. POSC 2.1 current
16 standard microfacies Grainstone with peloids. Probably faecal pellets, in places admixed with concentrated ostracode tests or forminifera. The interpreted environment is shallow water with only moderate water circulation. POSC 2.1 current
17 standard microfacies Grapestone, pelsparite, or grainstone with aggregate grains, isolated and agglutinated peloids, some coated grains. The interpreted environment is shelf with restricted water circulation and tidal flats. POSC 2.1 current
18 standard microfacies Foraminiferal or dasycladacean grainstones. The interpreted environment is tidal bars and channels of lagoons. POSC 2.1 current
19 standard microfacies Fenestral, laminated mudstone - wackestone, grading occasionally into pelsparite with fenestral fabrics. Ostracodes and peloids, sporadic forminifera, gastropods, and algae. The interpreted environment is restricted bays and ponds. POSC 2.1 current
20 standard microfacies Microbial stromatolite mudstone. The interpreted environment is commonest in the interdal zone. POSC 2.1 current
21 standard microfacies Spongiostrome mudstone. Convolute microbial fabric in fine-grained micrite lime mud sediment. The interpreted environment is tidal ponds. POSC 2.1 current
22 standard microfacies Micrite with large oncoids, wackestone, or floatstone. The interpreted environment is low-energy environments, shallow water, back-reef; oftgen on the edges of ponds or channels. POSC 2.1 current
23 standard microfacies Unlaminated, homogeneous unfossiliferous pure micrite; evaporitic minerals may occur. The interpreted environment is hypersaline tidal ponds. POSC 2.1 current
24 standard microfacies rudstone or floatstone with coarse lithoclasts and bioclasts. Clasts usually consist of unfossiliferous micrite; may be imbricated and cross-bedded; matrix sparse. The interpreted environment is lag deposit in tidal channels. POSC 2.1 current
sandstone sedimentary material At least 50% clastic, with sand sized grains predominating. POSC 2.1 current
siltstone or claystone sedimentary material At least 75% clastic, with silt and/or clay size particles being at least 90% of the clastic material. POSC 2.1 current
limestone or dolomite sedimentary material At least 75% carbonate (limestone or dolomite) grains. POSC 2.1 current
arenite sedimentary material Generally well-sorted sandstone, with 90% of the clastic grains being of sand size. Less than 25% calcareous material. POSC 2.1 current

material_class

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name classification _system description source version status
wacke sedimentary material A sandstone with more than 10% of the clastic grains being silt or smaller size. Generally not well sorted. Less than 25 calcareous material. POSC 2.1 current
sandy siltstone or claystone sedimentary material A siltstone or claystone with more than 10% of the clastic material being sand size. Less than 25% calcareous material. POSC 2.1 current
calcareous siltstone or claystone sedimentary material Silt or clay size particles dominate the clastic material. Between 25% and 50% of the total materials are carbonates. POSC 2.1 current
calcareous sandstone sedimentary material A sandstone with between 25% and 50% calcareous material. POSC 2.1 current
sandy limestone or dolomite sedimentary material Between 50% and 75% of the grains are carbonates, with at least half of the clastics being sand size or larger. POSC 2.1 current
argillaceous limestone or dolomite sedimentary material Between 50% and 75% of the grains are carbonates, with at least half of the clastics being silt size or smaller. POSC 2.1 current
shale sedimentary material A siltstone or claystone that shows fissility. POSC 2.1 current
sandy shale sedimentary material A sandy siltstone or claystone that shows fissility. POSC 2.1 current
shaly sand sedimentary material A wacke which contains fissile silts and clays. POSC 2.1 current
very well sorted degree of sorting The predominant grains are all in one class POSC 2.1 current
well sorted degree of sorting The predominant grains vary over 2 or 3 classes. POSC 2.1 current
moderately sorted degree of sorting The predominant grains vary over 4 or 5 classes. POSC 2.1 current
poorly sorted degree of sorting The predominant grains vary over 6 or 7 classes. POSC 2.1 current
very poorly sorted degree of sorting The predominant grains vary over more than 7 classes. POSC 2.1 current
very angular degree of rounding The least rounded classification. POSC 2.1 current
angular degree of rounding More worn than very angular, but less worn than sub-angular. POSC 2.1 current
sub-angular degree of rounding More worn than angular, but less worn than sub-rounded. POSC 2.1 current
sub-rounded degree of rounding More worn than sub-angular, but less worn than rounded. POSC 2.1 current
rounded degree of rounding More worn than sub-rounded, but less worn than well-rounded. POSC 2.1 current
well-rounded degree of rounding The most rounded class. POSC 2.1 current

material_class

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name classification _system description source version status
solid physical state A material which maintains a definite volume (low compressibility) and shape. POSC 2.1 current
liquid physical state A material which maintains a definite volume (low compressibility), but flows to take the shape of its container. POSC 2.1 current
gas physical state A material which is highly compressible, and generally fills its container. POSC 2.1 current
fluid fluid characterization A material which flows. Gases and liquids are fluids. A fluid generally has no shear strength. The distinction between a solid and a fluid is not always sharp. POSC 2.1 current
rheid fluid characterization A highly viscous fluid. Specifically, a substance (below its melting point) which deforms by viscous flow during the time of applied stress at an order of magnitude at least three times that of elastic deformation under similar conditions. POSC 2.1 current
water fluid characterization An aqueous fluid containing varying amounts of dissolved material. POSC 2.1 current
hydrocarbon fluid fluid characterization A classification of hydrocarbon fluids into consituent types based on production characteristics. POSC 2.1 current
produced fluid fluid characterization Classification of produced fluids based on primary fluid type. POSC 2.1 current
produced water fluid characterization A fluid which is primarily composed of formation water. POSC 2.1 current
steam fluid characterization The gas phase of water. POSC 2.1 current
salt water fluid characterization Water with an appreciable amount of salt, generally sodium ions, contained in. POSC 2.1 current
air fluid characterization A gas which is approximately 80 percent nitrogen, and 20 oxygen by volume. When referring to a drilling fluid (air drilling) natural gas may be the circulation fluid. POSC 2.1 current
produced gas fluid characterization A fluid which is primarily composed of hydrocarbons that exist as gases at surface conditions. POSC 2.1 current
produced oil fluid characterization A fluid which is primarily composed of hydrocarbons that exist as liquids at surface conditions. POSC 2.1 current
oil fluid characterization Crude petroleum oil and other hydrocarbons regardless of gravity which are produced at the wellhead in liquid form and the liquid hydrocarbons known as distillate or condensate recovered or extracted from gas, other than gas produced in association with oil and commonly known as casinghead gas. POSC 2.1 current
crude oil fluid characterization Any liquid hydrocarbon fluid produced normally from a well, excluding fluid produced in association with natural gas in a gas well. It is to be distinguished from refined oils that are manufactured from it. POSC 2.1 current
abandoned oil fluid characterization Waste oil permitted by an operator to escape from tanks or other storage facilities after production. POSC 2.1 current
natural gas fluid characterization Any hydrocarbon normally produced in gaseous form from a well, which at atmospheric conditions of temperature and pressure are in a gaseous phase. POSC 2.1 current
casinghead gas fluid characterization Gas produced with oil in oil wells, the gas being taken from the well through the casinghead at the top of the well, as distinguished from gas produced in a gas well. POSC 2.1 current
associated gas fluid characterization Gas occurring in the form of a gas cap associated with an oil zone. POSC 2.1 current

material_class

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name classification _system description source version status
gas lift gas fluid characterization Gas injected near the well completion for the purpose of lifting oil. The gas does not leave the wellbore, and it tends to lift the oil as it makes its way back to the surface. POSC 2.1 current
coalbed gas fluid characterization Gas contained in and emitted from coal deposits. POSC 2.1 current
natural gas liquid fluid characterization Hydrocarbons found in natural gas which have been liquefied at the surface in field facilities or in gas processing plants. They include, but are not limited to: ethane, propane, normal butane, isobutane, pentanes, debutanized natural gasoline, and plant condensate not recovered by mechanical separation. POSC 2.1 current
condensate fluid characterization Liquid hydrocarbons recovered by conventional surface spearators from gas produced from a condensate gas reservoir. Condensate, as generally defined by fifteen states, is the liquid hydrocarbons recovered at the surface that results from condensation of petroleum hydrocarbons existing initially in a gaseous phase in an underground reservoir. POSC 2.1 current
injected water injected materials A fluid which is primarily composed of water and is used primarily for injection into formations. POSC 2.1 current
chemical slug injected materials A fluid that is composed of specialized chemical components and is injected into a formation. POSC 2.1 current
radioactive tracer injected materials A fluid that contains radioactive components used to track the movement of the fluid. POSC 2.1 current
element chemical classification A fundamental substance that consists of atoms of only one kind and that singly or in combination constitute all matter. (Webster's 9th New Collegiate Dictionary) POSC 2.1 current
compound chemical classification A distinct substance formed by chemical union of two or more ingredients in definite proportion by weight. (Webster's 9th New Collegiate Dictionary) POSC 2.1 current
solution chemical classification A homogeneous mixture formed when a solid, liquid, or gaseous substance is mixed with a liquid or sometimes a gas or solid. (Webster's 9th New Collegiate Dictionary) POSC 2.1 current
isomer chemical classification A compound, radical, or ion that contains the same number of atoms of the same elements but differ in the structural arrangement and properties. (Webster's 9th New Collegiate Dictionary) POSC 2.1 current
Type 1 van Krevelen A type of organic material characterized by high H/C ratios (commonly 1.5 or more) and low O/C ratios (generally less than 0.1) and tend to generate oil. Generally from marine algal material or severe biodegradation of other organic material. POSC 2.1 current
Type 2 van Krevelen A type of organic material characterized by moderately high H/C ratios (generally less than 1.5) and moderately low O/C ratios (generally less than .2). Generally forms from marine plankton and microorganisms deposited in a reducing environment. POSC 2.1 current
Type 3 van Krevelen A type of organic material characterized by low H/C ratios (generally less than 1.0) and high O/C ratios (as high as 0.2 or 0.3). Is derived essentially from continental plants and contains much identifiable vegetal debris. POSC 2.1 current
exinite coal maceral group A coal maceral group derived from spores, cuticular matter, resins, and waxes. It is relatively rich in hydrogen. POSC 2.1 current
inertinite coal maceral group A coal maceral group, characterized by a relatively high carbon content, and a reflectance highter than that of vitrinite. POSC 2.1 current
vitrinite coal maceral group A coal maceral group distinguished by a middle level of reflectance, higher than exinite and lower than inertinite. It is characteristic of vitrain and is composed of humic material. POSC 2.1 current
native elements mineral class This class contains mineral that are elements in an uncombined, native state. The class includes minerals from the gold group, the platinum group, and the iron group. POSC 2.1 current
sulfides mineral class This class of minerals is characterized by metals coordinated around sulfur atoms in tetrahedral or octahedral form. POSC 2.1 current
sulfarsenides mineral class This class of minerals is characterized by metals coordinated around sulfur and arsenic atoms in tetrahedral or octahedral form. POSC 2.1 current

material_class

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name classification _system description source version status
arsenides mineral class This class of minerals is characterized by metals coordinated around arsenic atoms in tetrahedral or octahedral form. POSC 2.1 current
telluride mineral class This class of minerals is characterized by metals coordinated around tellurium atoms in tetrahedral or octahedral form. POSC 2.1 current
sulfosalt mineral class A class of mineral distinct from sulfides due to the metal-like role that As or Sb plays in their structure. POSC 2.1 current
oxides mineral class This group is made up of minerals containing one or more minerals combined with oxygen. POSC 2.1 current
hydroxides mineral class All structures in this group are characterized by the presence of the hydroxyl (OH)- group, or H20 molecules. POSC 2.1 current
halides mineral class The chemical class of halides is characterized by the dominance of the electronegative halogen ions, Cl-, Br-, F-, and I-. POSC 2.1 current
carbonates mineral class This class is characterized by a anionic, triangular (CO3)-2 groups. POSC 2.1 current
nitrates mineral class This class is characterized by a plane, triangular (NO3)-1 group. POSC 2.1 current
borates mineral class This class is characterized by a plane, triangular (BO3) group capable of polymerization into chains, sheets and isolated multiple groups. POSC 2.1 current
sulfates mineral class This class is characterized by a anionic tetrahedra containing a (SO4)-2 group. POSC 2.1 current
chromates mineral class This class is characterized by a anionic tetrahedra containing a (CrO4)-2 group. POSC 2.1 current
tungstates mineral class This class is characterized by a flattened tetrahedra with a square outline containing a (WO4)-2 group. POSC 2.1 current
molybdates mineral class This class is characterized by a flattened tetrahedra with a square outline containing a (MoO4)-2 group. POSC 2.1 current
phosphates mineral class This class is characterized by a anionic tetrahedra containing a (PO4)-3 group. POSC 2.1 current
arsenates mineral class This class is characterized by a anionic tetrahedra containing a (AsO4)-3 group. POSC 2.1 current
vanadates mineral class This class is characterized by a anionic tetrahedra containing a (VO4)-3 group. POSC 2.1 current
nesosilicates mineral class This class is characterized by isolated tetrahedra bound together only by ionic bonds from interstitial cations. Also called orthosilicates. POSC 2.1 current
sorosilicates mineral class This class is characterized by isolated, double tetrahedral groups formed by two SiO4 tetrahedra sharing a single apical oxygen. POSC 2.1 current
cyclosilicates mineral class This class is characterized by rings of linked SiO4 tetrahedra with a ration of Si to O of 1 to 3. Also called ring silicates. POSC 2.1 current
single chain inosilicates mineral class This class is characterized by an indefinitely extended chains of SiO4 tetrahedra, with 2 of the 4 oxygens in each tetrahedra being shared with neighboring tetrahedra. POSC 2.1 current

material_class

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name classification _system description source version status
double chain inosilicates mineral class This class is characterized by an indefinitely extended bands of SiO4 tetrahedra, with an alternating pattern of 2 and 3 oxygens in each tetrahedra being shared with neighboring tetrahedra. POSC 2.1 current
phyllosilicates mineral class This class is characterized by an indefinitely extended sheet of SiO4 tetrahedra, with 3 of the 4 oxygens in each tetrahedra being shared with neighboring tetrahedra. Also called sheet silicates. POSC 2.1 current
tectosilicates mineral class Minerals in this class are characterized by a three-dimensional framework of linked SiO4 tetrahedra in which all the oxygen ions in each tetrahedra are shared with neighboring tetrahedra. POSC 2.1 current
water based mud API drilling fluid A type of drilling fluid characterized by its use of water as the primary solvent. POSC 2.2 provisional
non-dispersed API drilling fluid These systems include spud muds, natural muds, and other lightly treated systems generally used for shallow wells or top-hole drilling. Thinners and dispersants are not added to disperse drill solids and clay particles. POSC 2.2 provisional
dispersed API drilling fluid At greater depths, where higher densities are required, or where hole conditions may be probaematic, muds are often dispersed, typically with lignosulfonates, lignites, or tannins. These and similar products are effective deflocculants and filtrate reducers. Potassium-containing chemicals are frequently used to provide greater shale inhibition. Specialized chemicals are also added to adjust or maintain specific mud properties. POSC 2.2 provisional
calcium treated API drilling fluid A system with divalent cations such as calcium or magnesium have been added to inhibit formation clay and shale swelling. POSC 2.2 provisional
polymer API drilling fluid Muds incorporating generally long-chain, high molicular-weight polymers. The are utilized to encapsulate drill solids to prevent dispersion and to coat shales for inhibition. They may also increase viscosity and reduce fluid loss. POSC 2.2 provisional
low solids API drilling fluid Systems in which the amount and type of solids are controlled. Total wolids should not range higher than 6% to 10% by volume. Clay solids should be some 3% or less and exhibit a ratio of drilled solids to bentonite of less than 2:1. POSC 2.2 provisional
saltwater systems API drilling fluid Saltwater muds are usually prepated from brackish, seawater, or produced-water sources. They generally have a chloride content of 10,000 to 190,000 mg/l. POSC 2.2 provisional
workover API drilling fluid Workover, completion, and drill-in fluids which are specialized systems designed to minimize formation damage or be used as packer fluids after completion operations. The impact of these systems to the productive formation must be capable of being reversed with remedial treatments. Systems consist of fluids which range from clear brines to polymer fluids to highly treated mud (packer) fluids. POSC 2.2 provisional
oil based mud API drilling fluid Oil-based systems are sued for a variety of applications where fluid stability and inhibition are necessary such as high-temperature wells, deep holes, and where sticking and hole stabilization is a problem. POSC 2.2 provisional
invert emulsion mud API drilling fluid Water-in-oil emulsions typically with calcium chloride brine as the emulsified phase and oil as the continuous phase. They may contain as much as 50% brine in the liquid phase.