creator: | Concept Definition Task Group of IUGS CGI Interoperability Working Group (http://www.cgi-iugs.org/tech_collaboration/interoperability_working_group.html) |
language: | en |
publisher: | Concept Definition Task Group of IUGS CGI Interoperability Working Group (http://www.cgi-iugs.org/tech_collaboration/interoperability_working_group.html) |
identifier: | http://resource.geosciml.org/classifierscheme/cgi/201202/compositioncategory |
title: | CGI Composition Category vocabulary |
format: | application/rdf+xml |
historyNote: | 2009-12-07. SMR add collections for mineralogical and sedimentary petrographic categories, improve annotation and notes on vocabulary. |
historyNote: | 2010-02-08. SMR Clean up namespace declarations so concept URI's follow CGI URN scheme; concepts have URN, are not document fragments. |
historyNote: | 2010-02-11 Add narrower relationship links by adding skos:narrower link in Protege, defining skos:narrower as inverse of skos:broader, calculating with Pellet reasoner to add inferred axioms, and using 'file/Export inferred axioms as ontology' in Protege. |
historyNote: | 2009-07-14. Generate SKOS encoding of vocabulary from Excel spreadsheet. |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/argillic |
Preferred label (en) | Argillic |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of clay is present |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/arkosic_detrital_mode |
Preferred label (en) | Arkosic detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that detrital mode for clastic rock (Q-F-L) includes less than 75 percent quartz and the feldspar to lithic ratio is greater than 3 to 1. This corresponds to the arkose field of Folk (1968). For clastic rocks with little or no matrix and cement, rocks in this detrital mode composition category will also have quartz-feldspathic mineralogical composition. |
Source (en) | Folk1968 |
Relationships: | |
Broader | Feldspathic detrital mode |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/asphaltic |
Preferred label (en) | Asphaltic |
Definition (en) | Material contains a significant amount of asphalt, which is “A dark brown to black viscous liquid or low-melting solid bitumen that consists almost entirely of carbon and hydrogen...[and] formed in oil-bearing rocks by the evaporation of volatiles...” (Jackson, 1997, p. 39). |
Source (en) | Jackson 1997 |
Relationships: | |
Broader | Carbonaceous |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/barium_bearing_carbonate_chemistry |
Preferred label (en) | Barium-bearing carbonate chemistry |
Definition (en) | CO3 is the predominant anion, and greater than 5 mole percent of cations are Ba. |
Source (en) | This vocabulary |
Relationships: | |
Broader | Carbonate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/bioclastic |
Preferred label (en) | Bioclastic |
Definition (en) | Carbonate sedimentary material contains significant broken skeletal material |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/calcareous |
Preferred label (en) | Calcareous |
Definition (en) | Calcium carbonate minerals are present, carbonate minerals form less than 50 percent of rock, material contains sufficient CaCO3 to react forming bubbles when hydrochloric acid is applied. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Carbonate bearing |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/calcareous_monomeralic_carbonate |
Preferred label (en) | Calcareous monomeralic carbonate |
Definition (en) | Carbonate minerals form greater than 75 percent of rock, and calcium carbonate minerals forms greater than 75 percent of carbonate minerals. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Monomineralic carbonate |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/calcium_rich_carbonate_chemistry |
Preferred label (en) | Calcium-rich carbonate chemistry |
Definition (en) | CO3 is the predominante anion, and the Ca is the most abundant (mole percent) cation. |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Broader | Carbonate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/calcsilicate |
Preferred label (en) | Calcsilicate |
Definition (en) | Material consists of greater than or equal to 50 percent calcsilicate or carbonate minerals and carbonate minerals less than or equal to calcsilicate minerals in mineral mode. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Impure calcsilicate or carbonate |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/calcsilicate_bearing |
Preferred label (en) | Calcsilicate-bearing |
Definition (en) | Calcsilicate minerals of any sort are present, but less than 50 percent of rock |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/carbonaceous |
Preferred label (en) | Carbonaceous |
Definition (en) | Material containing significant carbon or hydrocarbon mineral phases, including graphite, coal, oil, gas, lignite, peat. |
Source (en) | This vocabulary |
Relationships: | |
Narrower | Asphaltic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/carbonaceous_chemistry |
Preferred label (en) | Carbonaceous chemistry |
Definition (en) | Containing greater than 5 percent reduced carbon in compounds that are typically the diagenetic products of dead organisms (e.g. coal, bitumen and petroleum). 5 percent value is chosen for consistency with SLTTs usage of term carbonaceous. |
Source (en) | Struik2002; SLTTs2004; This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/carbonate |
Preferred label (en) | Carbonate |
Definition (en) | Material consists of greater than 50 percent calcsilicate or carbonate minerals and carbonate minerals greater than calcsilicate minerals in mineral mode. Metacarbonate of NADMSC SLTTm (2004) terminology, adopted here for non-genetic use. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Impure calcsilicate or carbonate |
Narrower | Monomineralic carbonate |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/carbonate_bearing |
Preferred label (en) | Carbonate bearing |
Definition (en) | Carbonate minerals of any sort are present, but less than 50 percent of rock. |
Source (en) | This vocabulary |
Relationships: | |
Narrower | Calcareous |
Narrower | Dolomitic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/carbonate_chemistry |
Preferred label (en) | Carbonate chemistry |
Definition (en) | The carbonate (CO3) anion is the predominant anion (by mole percent) in chemical analysis. Sub-categories may be defined by dominant cation. Material in this chemical class overlaps with the monomineralic carbonate class, and probably overlaps with the Carbonate class in the mineralogical composition classification. |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Narrower | Barium-bearing carbonate chemistry |
Narrower | Calcium-rich carbonate chemistry |
Narrower | Iron-bearing carbonate chemistry |
Narrower | Magnesium-rich carbonate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/chloride_chemistry |
Preferred label (en) | Chloride chemistry |
Definition (en) | Chloride is the most abundant (mole percent) anion |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Broader | Halide chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/chloritic |
Preferred label (en) | Chloritic |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of chlorite group minerals are present |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/composition_not_specified |
Preferred label (en) | Composition not specified |
Definition (en) | Composition not specified. Use in normative descriptions where any composition property is allowed. |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/dolomite_monomineralic_carbonate |
Preferred label (en) | Dolomite monomineralic carbonate |
Definition (en) | Carbonate minerals form greater than 75 percent of rock, and dolomite forms greater than 75 percent of carbonate minerals. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Monomineralic carbonate |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/dolomitic |
Preferred label (en) | Dolomitic |
Definition (en) | Dolomite is present, carbonate minerals form less than 50 percent of rock. |
Source (en) | This vocabulary |
Relationships: | |
Broader | Carbonate bearing |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/feldspathic |
Preferred label (en) | Feldspathic |
Definition (en) | Sedimentary material contains significant feldspar mineral content |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/feldspathic_detrital_mode |
Preferred label (en) | Feldspathic detrital mode |
Definition (en) | General sandstone petrography term for a sandstone in which the ratio of feldspar to lithic fragments is greater than 1:1 and less than 75 percent quartz is present in the detrital mode. Subsumes lithic arkosic and arkosic sandstone petrographic composition classes. Usage of modifier feldspathic is consistent with petrographic subdivisions of Dott (1964) and Williams, Turner and Gilbert (1982) |
Source (en) | Dott1964; Folk1968 |
Relationships: | |
Narrower | Arkosic detrital mode |
Narrower | Lithic arkosic detrital mode |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/feldspathic_lithic_detrital_mode |
Preferred label (en) | Feldspathic lithic detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that detrital mode for clastic rock (Q-F-L) includes less than 75 percent quartz and the feldspar to lithic ratio is between 1 to 1 and 1 to 3. This corresponds to the feldspathic litharenite field of Folk (1968). Rocks in this class are likely to be quartzo-feldspathic in terms of mineralogical composition terms in this vocablary, but because the mineralogical composition of the lithic fraction is not constrainged, this correlation is not necessary. |
Source (en) | Folk1968 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/ferromagnesian |
Preferred label (en) | Ferromagnesian |
Definition (en) | Material consists of greater than 40 percent dark ferromagnesian silicate minerals. Standard term defined by Bates and Jackson (1987) to mean 'containing iron and magnesium'. Subsumes mafic and ultramafic. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Narrower | Mafic |
Narrower | Ultramafic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/ferruginous |
Preferred label (en) | Ferruginous |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of non-silicate iron minerals (hematite, magnetite, siderite...) are present. Rocks containing abundant iron-rich silicate minerals would use the 'Ferromagnesian' terms. |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/fluoride_chemistry |
Preferred label (en) | Fluoride chemistry |
Definition (en) | Fluorine is the most abundant (mole percent) anion |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Broader | Halide chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/halide_chemistry |
Preferred label (en) | Halide chemistry |
Definition (en) | One or more of halide group elements (F, Cl, Br, I) are most abundant (mole percent) anion |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Narrower | Chloride chemistry |
Narrower | Fluoride chemistry |
Narrower | Nitrate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/high_silica_chemistry |
Preferred label (en) | High silica chemistry |
Definition (en) | Containing 65 percent or more SiO2 by weight. Syn acid. |
Source (en) | Struik2002; SLTTs2004; This vocabulary |
Relationships: | |
Broader | Silicate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/impure_calcsilicate_or_carbonate |
Preferred label (en) | Impure calcsilicate or carbonate |
Definition (en) | Material consists of greater than 50 percent calcsilicate or carbonate minerals and relative proportion of calcsilicate and carbonate minerals is unknown or not specified. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Narrower | Calcsilicate |
Narrower | Carbonate |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/intermediate_silica_chemistry |
Preferred label (en) | Intermediate silica chemistry |
Definition (en) | Containing SiO2 in the range 52-65 percent, sometimes described as "intermediate" rocks. |
Source (en) | Struik2002; SLTTs2004; This vocabulary |
Relationships: | |
Broader | Silicate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/intraclastic |
Preferred label (en) | Intraclastic |
Definition (en) | Carbonate sedimentary material contains signficant intraclast content |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/iron_bearing_carbonate_chemistry |
Preferred label (en) | Iron-bearing carbonate chemistry |
Definition (en) | CO3 is the predominant anion, and iron is greater than 5 mole percent of the cations (includes Fe, Mg, Mn, Ba, Sr, Ca...). |
Source (en) | This vocabulary |
Relationships: | |
Broader | Carbonate chemistry |
Narrower | Iron-rich carbonate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/iron_rich_carbonate_chemistry |
Preferred label (en) | Iron-rich carbonate chemistry |
Definition (en) | CO3 is the predominant anion, and iron is the most abundant (mole percent) cation |
Source (en) | This vocabulary |
Relationships: | |
Broader | Iron-bearing carbonate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/lithic |
Preferred label (en) | Lithic |
Definition (en) | Sedimentary material contains significant detrital rock fragments derived by erosion from older, pre-existing rock materials |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/lithic_arkosic_detrital_mode |
Preferred label (en) | Lithic arkosic detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that detrital mode for clastic rock (Q-F-L) includes less than 75 percent quartz and the ratio of lithic fragments to feldspar is between 1:1 and 1:3. This corresponds to the lithic arkose field of Folk (1968); the 75 percent quartz boundary is chosen to be consistent with quartzsose composition as defined in the mineralogic compostion terms vocabulary. Because of the abundance of lithic fragments for which the mineralogic composition is not specified, and the presence of undiscernible matrix and cement that are not incuded in the detrital mode, corresondence with the mineralogical composition terms is very approximate. |
Source (en) | Folk1968 |
Relationships: | |
Broader | Feldspathic detrital mode |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/lithic_detrital_mode |
Preferred label (en) | Lithic detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that detrital mode for clastic rock (Q-F-L) includes less than 75 percent quartz and the lithic to feldspar ratio is greater than 3 to 1. This corresponds to the litharenite field of Folk (1968). Because the mineralogy of the lithic fragments is not constrained, the mineralogical composition is largely independent of the detrital mode composition for this class. |
Source (en) | Folk1968 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/lithic_rich_detrital_mode |
Preferred label (en) | Lithic rich detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that the ratio of lithic fragments to feldspar is greater than 1:1, and less than 75 percent quartz is present in the detrital mode. Because the mineralogy of the lithic fragments is not constrained, the mineralogical composition is largely independent of the detrital mode composition for this class. |
Source (en) | Dott1964; Folk1968 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/low_silica_chemistry |
Preferred label (en) | Low silica chemistry |
Definition (en) | Containing SiO2 in the range 44-52 percent. Syn basic. |
Source (en) | Struik2002; SLTTs2004; This vocabulary |
Relationships: | |
Broader | Silicate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/mafic |
Preferred label (en) | Mafic |
Definition (en) | Material consists of greater than or equal to 40 percent and less than 90 percent ferromagnesian silicate minerals. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Ferromagnesian |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/magnesium_rich_carbonate_chemistry |
Preferred label (en) | Magnesium-rich carbonate chemistry |
Definition (en) | CO3 is the predominant anion, and Mg is the most abundant (mole percent) cation. |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Broader | Carbonate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/metallic_oxide_bearing |
Preferred label (en) | Metallic oxide bearing |
Definition (en) | Greater than accessory amounts (greater than 5 percent by volume) of base metal oxide minerals such as magnetite (Fe3O4) or pyrolusite (MnO2) are present. |
Source (en) | Struik2002; SLTTs2004; This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/metaluminous |
Preferred label (en) | Metaluminous |
Definition (en) | Chemical composition term used for igneous rocks, denoting that content of aluminum oxide is greater than sodium oxide plus potassium oxide, but aluminum oxide less than sum of Na, K and Ca oxide. |
Source (en) | Shand 1947 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/micaceous |
Preferred label (en) | Micaceous |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of mica group mineral are present |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/mono_mineralic |
Preferred label (en) | Mono mineralic |
Definition (en) | Greater than 75 percent of the material consists of a single mineral species. |
Source (en) | NADM SLTTm 2004 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/monomictic |
Preferred label (en) | Monomictic |
Definition (en) | Grains or clasts are composed of a single rock or mineral type (Jackson, 1997) |
Source (en) | Jackson 1997 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/monomineralic_carbonate |
Preferred label (en) | Monomineralic carbonate |
Definition (en) | Rock in which carbonate minerals form greater than 75 percent of rock. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Carbonate |
Narrower | Calcareous monomeralic carbonate |
Narrower | Dolomite monomineralic carbonate |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/nitrate_chemistry |
Preferred label (en) | Nitrate chemistry |
Definition (en) | Nitrate (NO3) is most abundant (mole percent) anion. |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: | |
Broader | Halide chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/other_composition |
Preferred label (en) | Other composition |
Definition (en) | Composition is known but doesn’t' fit in any other category |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/oxide |
Preferred label (en) | Oxide |
Definition (en) | Material predominantly composed of oxide minerals |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/pelitic |
Preferred label (en) | Pelitic |
Definition (en) | Material for which the sum of modal quartz+feldspar+ mica + aluminous mineral is greater than or equal to 70 percent, and aluminous mineral + mica content is greater than or equal to 40 percent. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Quartz-feldspar-pelitic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/peralkaline |
Preferred label (en) | Peralkaline |
Definition (en) | Aluminum oxide (Al2O3) is less than sum of K and Na oxide. |
Source (en) | Shand 1947 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/peraluminous |
Preferred label (en) | Peraluminous |
Definition (en) | Aluminum oxide (Al2O3) greater than sum of Na, K and Ca oxide. |
Source (en) | Shand 1947 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/petroliferous |
Preferred label (en) | Petroliferous |
Definition (en) | Crude oil or natural gas is present, generally in trace amounts, commonly detected by smell |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/phosphate_chemistry |
Preferred label (en) | Phosphate chemistry |
Definition (en) | Phosphate (PO4) is the most abundant (mole percent) anion. |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/phosphatic |
Preferred label (en) | Phosphatic |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of phosphate minerals are present |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/polymictic |
Preferred label (en) | Polymictic |
Definition (en) | Grains or clasts are composed of many mineral or rock types |
Source (en) | Jackson, 1997, p. 501 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/quartz_feldspar_pelitic |
Preferred label (en) | Quartz-feldspar-pelitic |
Definition (en) | Material for which the sum of modal quartz+feldspar+ mica + aluminous mineral is greater than or equal to 70 percent. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Narrower | Pelitic |
Narrower | Quartzo-feldspathic |
Narrower | Semi-pelitic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/quartzo_feldspathic |
Preferred label (en) | Quartzo-feldspathic |
Definition (en) | Material for which the sum of modal quartz+feldspar+ mica + aluminous mineral is greater than or equal to 70 percent, and quartz + feldspar (sensu Robertson, 1999) greater than 60 percent. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Quartz-feldspar-pelitic |
Narrower | Quartzose |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/quartzose |
Preferred label (en) | Quartzose |
Definition (en) | Material consists of greater than or equal to 75 percent quartz. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Quartzo-feldspathic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/quartzose_detrital_mode |
Preferred label (en) | Quartzose detrital mode |
Definition (en) | Detrital mineral grains in a granular rock consist of greater than 95 percent quartz. This petrographic criteria follows the most restrictive definition of the composition field at the quartz vertex of the sandstone QFL triangle (Folk, 1968). This use of term quartzose is more restrictive that that used in the mineralogical composition term vocabulary, reflecting the interpretive significance of pure quartz sandstones in sedimentary petrology. |
Source (en) | Folk1968; This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/semi_pelitic |
Preferred label (en) | Semi-pelitic |
Definition (en) | Material for which the sum of modal quartz+feldspar+ mica + aluminous mineral is greater than or equal to 70 percent, and quartz+ feldspar less than 60 percent |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Quartz-feldspar-pelitic |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/silicate_chemistry |
Preferred label (en) | Silicate chemistry |
Definition (en) | Composed of minerals whose crystal structure contains SiO4 tetrahedra, either isolated or joined through one or more oxygen atoms to form groups, chains, sheets or three-dimensional structures with metallic cations. Composition ranges from 20-100 percent SiO2. Typically some Al substitutues for silica. A survey of chemical analyses in the Georock database (query FOR ALL GEOLOGICAL SETTINGS, MATERIAL: WHOLE ROCK (AND VOLCANIC GLASS), PUB. YEARS: 2005-1970), 10/10/2005 state, http://georoc.mpch-mainz.gwdg.de/georoc/Entry.html) discovered that the lowest silica (Si02) content for igneous rock is about 20 percent. This is consistent with the lowest silica content found for a silicate mineral is about 21 percent for a chlorite variety found by scanning the mineral analyses in Deer, Howie, and Zussman (1966). |
Source (en) | Neuendorf et al 2005; Struik 2002; This vocabulary |
Relationships: | |
Narrower | High silica chemistry |
Narrower | Intermediate silica chemistry |
Narrower | Low silica chemistry |
Narrower | Very low silica chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/silicic |
Preferred label (en) | Silicic |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of silica, amorphous, as quartz, or any of the silica polymorphs are present |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sub_feldspathic_detrital_mode |
Preferred label (en) | Sub feldspathic detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that detrital mode for clastic rock (Q-F-L) includes less than 50 percent lithic fragments, between 75 and 95 percent quartz (thus less than 25 percent feldspar). This corresponds to the subarkose field of Folk (1968); the 75 percent quartz boundary is consistent with the quartzsose composition as defined in the mineralogic compostion terms vocabulary, but if more than a few percent 'matrix' or cement is present, this is not necessarily equivalent to the mineralogical composition term. |
Source (en) | Folk1968 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sub_lithic_detrital_mode |
Preferred label (en) | Sub lithic detrital mode |
Definition (en) | Sandstone petrographic composition term indicating that detrital mode for clastic rock (Q-F-L) includes more than 50 percent lithic fragments, between 75 and 95 percent quartz (thus less than 25 percent feldspar). This corresponds to the sublitharenite field of Folk (1968); the 75 percent quartz boundary is consistent with quartzsose composition as defined in the mineralogic compostion terms vocabulary. |
Source (en) | Folk1968 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/subaluminous |
Preferred label (en) | Subaluminous |
Definition (en) | Aluminum oxide within 10 percent of sum of Na and K oxide. |
Source (en) | Shand 1947 |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sulfate |
Preferred label (en) | Sulfate |
Definition (en) | Material predominantly composed of sulfate minerals |
Source (en) | This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sulfate_chemistry |
Preferred label (en) | Sulfate chemistry |
Definition (en) | Sulfate is the most abundant anion |
Source (en) | Struik etal 2002; This vocabulary |
Relationships: |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sulfide |
Preferred label (en) | Sulfide |
Definition (en) | Material predominantly composed of sulfide minerals |
Source (en) | This vocabulary |
Relationships: | |
Broader | Sulfide bearing |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sulfide_bearing |
Preferred label (en) | Sulfide bearing |
Definition (en) | Greater than accessory amount (greater than 5 percent by volume) of sulfide mineral are present |
Source (en) | This vocabulary |
Relationships: | |
Narrower | Sulfide |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sulfide_chemistry |
Preferred label (en) | Sulfide chemistry |
Definition (en) | Sulfur is the most abundant anion; cations are metals or semimetals. |
Source (en) | Neuendorf et al 2005; Struik 2002; This vocabulary |
Relationships: | |
Narrower | Sulfosalt chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/sulfosalt_chemistry |
Preferred label (en) | Sulfosalt chemistry |
Definition (en) | Sulfide in which a semimetal (As, Sb, Bi) is present in a cation role |
Source (en) | Neuendorf et al 2005; Struik 2002; This vocabulary |
Relationships: | |
Broader | Sulfide chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/ultramafic |
Preferred label (en) | Ultramafic |
Definition (en) | Material consists of greater than 90 percent ferromagnesian silicate minerals.. |
Source (en) | NADM SLTTm 2004 |
Relationships: | |
Broader | Ferromagnesian |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/very_low_silica_chemistry |
Preferred label (en) | Very low silica chemistry |
Definition (en) | Containing between about 20 and 44 percent SiO2. A survey of chemical analyses in the Georock database (query FOR ALL GEOLOGICAL SETTINGS, MATERIAL: WHOLE ROCK (AND VOLCANIC GLASS), PUB. YEARS: 2005-1970), 10/10/2005 state, http://georoc.mpch-mainz.gwdg. syn ultrabasic. |
Source (en) | Struik2002; SLTTs2004; This vocabulary |
Relationships: | |
Broader | Silicate chemistry |
URI | http://resource.geosciml.org/classifier/cgi/compositioncategory/volcanic_lithic |
Preferred label (en) | Volcanic lithic |
Definition (en) | Sedimentary material contains significant broken volcanic rock fragments or vitric fragments, irrespective of their pyroclastic or epiclastic origin. |
Source (en) | This vocabulary |
Relationships: |
URI | |
Preferred label (en) | CompositionCategory |
Definition (en) | This file contains the 201012 version of CGI Composition Category vocabulary. Includes terms for chemical, sedimentary petrographic, and mineralogical composition spaces, which are grouped into skos:collections. |
Relationships: | |
Notes: | |
History note (en) | 2010-11-27 SMR replace URN with http URI according to CGI URI scheme; update version number to 201012 |