contact type concepts
This resource defines the concept space for Contact Types by extension; it includes all concepts in this conceptScheme, as well as concepts in previous versions of the scheme.
CGI Contact Type
this vocabulary
A metasomatic facies contact separating rocks that have undergone alteration of a particular facies from those that have undergone metasomatism of another facies. Alteration is a kind of metasomatism that does not introduce economically important minerals.
alteration facies contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An unconformable contact between two geological units in which the older, underlying rocks dip at an angle different from the younger, overlying strata, usually in which younger sediments rest upon the eroded surface of tilted or folded older rocks.
angular unconformable contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An unconformity in which onlapping strata are truncated against a steep topographic scarp.
buttress unconformity
FGDC
A contact between bodies of material having different ages of origin.
chronostratigraphic zone contact
this vocabulary
A geophysical contact between bodies of material distinguished based on electrical conductivity characteristics
update definition to allow definition of unit based on any characteristics related to electrical conductivity. SMR 2011-02-16
conductivity contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
A contact separating two geological units in which the layers are formed one above the other in order by regular, uninterrupted deposition under the same general conditions.
conformable contact
Note that usage of geologic unit here is per NADM C1 2004, denoting a body of material. Lines on geologic maps may also delineate featured defined geomorphically-- craters, terraces, shorelines, scarps that are not inherently geologic unit boundaries in this sense.
adapted from Jackson, 1997, page 137; NADM C1 2004
A surface that separates geologic units. Very general concept representing any kind of surface separating two geologic units, including primary boundaries such as depositional contacts, all kinds of unconformities, intrusive contacts, and gradational contacts, as well as faults that separate geologic units.
contact
this vocabulary
A lithogenetic bundary separating rock masses that have different deformation structure, e.g. sheared rock against non sheared rock, brecciated rock against non-brecciated rock.
deformation zone contact
this vocabulary
A geophysical contact separating bodies of material with different density characteristics, generally determined through measurement and modelling of gravity variations.
modify definitionn to allow unit definition based on any density-based characteristic SMR 2011-02-16
density contact
this vocabulary
Lithogenetic contact at which a sedimentary or volcanic rock has been deposited on (or against) another rock body. The relationship between the older underlying rocks and younger overlying rocks is unknown or not specfied.
depositional contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An unconformable contact between two geological units in which the bedding of the older, underlying unit is parallel to the bedding of the younger, overlying unit, but in which the contact between the two units is marked by an irregular or uneven surface of appreciable relief.
disconformable contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
A contact separating two bodies of material across which one body has slid past the other.
faulted contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
A contact between regions characterised by their geological history or by similar structural, petrographic or stratigraphic features
geologic province contact
this vocabulary
A contact separating bodies of material in the earth that have different geophysical properties. Use for boundaries that are detected by geophysical sensor techniques as opposed to direct lithologic observation.
geophysical contact
this vocabulary
Glacial stationary lines are inferred outcrop of the glacial contact representing the boundary of a glacier at its maximum (or some stable) extent, thus they would be instances of this contact type, with metadata indicating observation method by inference.
A boundary between a subglacial geomorphic unit and a periglacial geomorphic unit, marking the maximum extent of glacial cover. This can be thought of as the outcrop of the contact between a glacier and its substrate at some time at each point along the boundary. This contact type is included as an interim concept, assuming that in the future, there will be extensions to account better for geomorphic units and line types.
glacial stationary line
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An intrusive contact between a younger igneous rock and an older, pre-existing geological unit into which it has been intruded.
igneous intrusive contact
this vocabulary
A lithogenetic contact separating lithologically distinct phases of a single intrusive body. Does not denote nature of contact (intrusive or gradation).
igneous phase contact
this vocabulary
surface that bounds a body of rock affected by an extraterrestrial impact event
impact structure boundary
this vocabulary
A non-faulted contact separating bodies of material in the earth that have different lithologic character or geologic history.
lithogenetic contact
this vocabulary
A geophysical contact separating bodies of material distinguished based on properties related to magnetic fields.
magnetic contact
this vocabulary
A magentic contact between bodies of material with different polarity of remnant magnetization, e.g. between sections of ocean floor with different polarity.
magnetic polarity contact
this vocabulary
A magnetic contact between bodies of material distinguished based on magnetic susceptibility characteristics.
reword definition to generalize to allow unit definition based on any magnetic susceptibility characteristics. SMR 2011-02-16
magnetic susceptiblity contact
this vocabulary
A magnetic contact between bodies of material distinguished based on any aspect of magnetization of material in the units.
reword definition to generalize to allow unit definition based on any aspect of magnetization. SMR 2011-02-16
magnetization contact
this vocabulary
Lithogenetic contact separating rocks that have different lithologic properties related to metamorphism, metasomatism, alteration, or mineralization. Generally separates metamorphic rock bodies, but may separate metamorphosed (broadly speaking) and non-metamorphosed rock.
metamorphic contact
this vocabulary
A metamorphic contact separating rocks that have undergone metamorphism of a particular facies from those that have undergone metamorphism of another facies.
metamorphic facies contact
this vocabulary
A metamorphic contact separating rocks that have undergone metasomatism of a particular facies from those that have undergone metasomatism of another facies. Metasomatism is distinguished from metamorphism by significant changes in bulk chemistry of the affected rock.
metasomatic facies contact
this vocabulary
A metasomatic facies contact separating rocks which have been mineralised and contain a particular mineral assemblage from those which contain a different assemblage. Mineralization is a kind of metasomatism that introduces ecomomically important minerals.
mineralisation assemblage contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An unconformable contact between an underlying, older nonstratified geological unit (usually intrusive igneous rocks or metamorphics) and an overlying, younger stratified geological unit.
nonconformable contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An unconformable contact between two geological units in which the bedding of the older, underlying unit is parallel to the bedding of the younger, overlying unit, in which the contact between the two units is planar, and may be coincident with a bedding plane.
paraconformable contact
this vocabulary
A geophysical contact separating bodies of material distinguished based on the characteristics of emitted of radiant energy related to radioactivity (e.g. gamma rays).
reword definition to generalize to allow unit definition based on any characteristics related to radiant energy emissions related to radioactivity. SMR 2011-02-16
radiometric contact
base on Nichols, Gary, 1999, Sedimentology and stratigraphy, Blackwell, p. 62-63.
A lithogenetic contact separating essentially coeval sedimentary material bodies distinguished by characteristics reflecting different physical or chemical processes active at the time of deposition of the sediment.
sedimentary facies contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
An intrusive contact between a sedimentary rock unit and plastic sediment (e.g., clay, chalk, salt, gypsum, etc.), forced upward into it from underlying sediment
sedimentary intrusive contact
this vocabulary
A geophysical contact separating bodies of material defined based on their seismic character. Seismic character is based on transmission of vibrations (seismic waves) through a rock body, and relates to the velocity of transmission, and the nature of reflection, refraction, or transformation of seismic waves by inhomogeneities in the rock body.
seismic contact
Neuendorf, K.K.E, Mehl, J.P. & Jackson, J.A. (eds), 2005. Glossary of geology, 5th Edition. American Geological Institute, Alexandria, 779 p.
A contact separating two geological units in which the younger unit succeeds the older after a substantial hiatus in deposition.
unconformable contact
caldera
cauldron
crater
this vocabulary, concept to encompass boundary of caldron, caldera, or crater.
boundary around a body of rock that is within a zone of subsidence or cratering produced by volcanic activity.
volcanic subsidence zone boundary
this vocabulary
A lithogenetic contact separating bodies of material differentiated based on lithologic properties related to weathering.
weathering contact
Concept Definition Task Group of IUGS CGI Interoperability Working Group (http://www.cgi-iugs.org/tech_collaboration/interoperability_working_group.html)
CGI IWG Concept Definition Task Group.
application/rdf+xml
http://resource.geosciml.org/classifierscheme/cgi/201211/contacttype
en
Concept Definition Task Group of IUGS CGI Interoperability Working Group (http://www.cgi-iugs.org/tech_collaboration/interoperability_working_group.html)
CGI Contact Type Categories
201211
2009-12-07 SMR Update metadata properties for version, creator, title, and format. Change skos:HistoryNote to dc:source for information on origin of terms and definitions.
This file contains the 201202 version of CGI Contact type vocabulary. Use to populate the contactType property on the GeoSciML Contact feature type. This property categorizes the the type of contact (e.g. intrusive, unconformity, bedding surface, compositional layering, phase boundary) between geologic units for a GSML.GeologicStructure.Contact instance.
2012-02-27 SMR add skos:exactMatch triples to map URIs for concepts in this vocabulary to number-token URIs in 201012 version of same concepts.
2012-02-07 SMR update URI to replace numeric final token with English-language string as in original URN scheme.
Revised from ContactType200811 with addition of impact_structure_boundary and volcanic_subsidence_zone_boundary, and addition of more metadata annotation
2011-02-16 SMR replace URN with cgi http URI's. Last changes to fix URN for conceptScheme that was not updated in original updates.
2012-11-24 SMR Update to 201211 version; add collection entity, check all pref labels are lower case, remove owl:NamedIndividual and Owl:Thing rdf:types.
CGI Contact Type Categories
Contact type vocabulary