Geoscience Ontology, Geologic Qualities

Specification of the strength of observed alteration. Can be used on Geologic_Unit or Rock_Material

Bearing of a horizontal line relative to north. Use for specifying the orientation of planar or linear features.

A property that specifies the degree to which an aggregation of EarthMaterial particles is a distinct solid material. Consolidation and induration are related concepts specified by this property. They define a continuum from unconsolidated material to very hard rock. Induration is the degree to which a consolidated material is made hard, operationally determined by how difficult it is to break a piece of the material. Consolidated materials may have varying degrees of induration (NADMSC, 2004)

the maximum angle between a horizontal surface and a planar feature

property to specify if a surface is directed, i.e. has a top and bottom. Values: {upright, overturned, unknown}

Surface dips between 10 and 30 degrees; typically used to describe orientation of fold hinge surface or axial surface, but could be applied to any geologic surface.

line plunges between 10 and 30 degrees.

Protolith structures almost always obliterated, evidence of partial melting common. Includes rocks metamorphosed in high-temperature amphibolite, pyroxene hornfels, and medium to high-temperature eclogite facies. Mineral assemblages according to Fry (1984) Table 10-1: ultramafic-olivine, anthophyllite, cummingtonite, enstatite, mafic-hornblende, (diopside, garnet), calc-aluminous basic-plagioclase, pelite, semi-pelite -- K-feldspar, biotite, quartz, Al-minerals (garnet), migmatite.

Surface dips between 0 and 10 degrees. Equivalent term 'recumbent' used to describe orientation of fold hing surface or axial surface

line plunges between 0 and 10 degrees.

Surface dips between 10 and 80 degrees; typically used to describe orientation of fold hinge surface or axial surface, but could be applied to any geologic surface.

specification of the orientation of a line in space, using a trend (bearing of horizontal projection of line relative to geographic north) and plunge (inclination of line measured positive downward in degrees from local horizontal). TBD: add 'isdirected property to indicate if the line is directed (e.g. sense of shear), values should be Boolean,

Metamorphic effects clearly visible, protolith structures typically still observable, includes rocks metamorphosed in greenschisthigh-temperature blueschist, very low temperature eclogite facies. Mineral assemblages according to Fry (1984) Table 10-1: ultramafic-serpentine (talc, magnesite), mafic-chlorite, actinolite (garnet), calc-aluminous basic-albite, epidote, pelite, semi-pelite -- white mica, chlorite, quartz, biotite (garnet, Al-minerals).

a measure of how much a material will become magnetized in an applied magnetic field. It is the ratio of magnetization M (magnetic moment per unit volume) to the applied magnetizing field intensity H. This allows a simple classification, into two categories, of most materials' responses to an applied magnetic field: an alignment with the magnetic field, χ > 0, called paramagnetism, or an alignment against the field, χ < 0, called diamagnetism.

Protolith structure typically obliterated. Includes rocks metamorphosed in high-temperature epidote-amphibolite, low-temperature amphibolite, and low temperature eclogite facies. Mineral assemblages according to Fry (1984) Table 10-1: ultramafic-olivine, talc (magnesite, anthophyllite), mafic-hornblende, (diopside, garnet), calc-aluminous basic-plagioclase, pelite, semi-pelite -- white mica, biotite, quartz (garnet, Al-minerals).

applies to Earth_Material or Geologic_Unit

Rock is metamorphosed, may have any value for metamorphic grade except 'not metamorphosed'.

Surface dips between 30 and 60 degrees; typically used to describe orientation of fold hing surface or axial surface, but could be applied to any geologic surface.

line plunges between 30 and 60 degrees.

Rock is not metamorphose'.

top of surface is facing downward, toward Earth interior.

Quality to specify the orientation of a surface in a geogaphic reference system

Numeric value should be between +90 and -90. Negative values only valid if the linear feature is directed.

line plunges between 10 and 80 degrees.

Surface dips between 60 and 80 degrees; typically used to describe orientation of fold hing surface or axial surface, but could be applied to any geologic surface.

line plunges between 60 and 80 degrees.

Facing direction is unknown {@en}

top of surface is away from center of earth.

Surface dips between 80 and 90 degrees. Equivalent term 'upright' is used to describe orientation of fold hing surface or axial surface

line plunges between 80 and 90 degrees.

Protolith structures almost always obliterated. Includes rocks metamorphosed in granulite (or sanidinite), and high-temperature eclogite facies. Mineral assemblages according to Fry (1984) Table 10-1: ultramafic-olivine, enstatite, mafic-hypersthene, diopside (hornblende), calc-aluminous basic-plagioclase, pelite, semi-pelite -- hypersthene + Al-minerals (K-feldspar, quartz), or sapphirine.

Rock very slightly metamorphosed, protolith structure ubiquitous, mineral assemblage of zeolite facies, subgreenschist facies, or low temperature part of blueschist facies. Mineral assemblages according to Fry (1984) Table 10-1: ultramafic-serpentine (quartz, magnesite), mafic-clay, chlorite, relict igneous minerals, calc-aluminous basic-zeolite, pumpellite, epidote, albite, pelite, semi-pelite -- clays, chlorite, sericite, quartz.