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Related to hypabyssal: plutonic rock


 (hĭp′ə-bĭs′əl, hī′pə-)
adj. Geology
Solidifying chiefly as a minor intrusion, especially as a dike or sill, before reaching the earth's surface. Used of rocks.

hyp′a·bys′sal·ly adv.


(Geological Science) (of igneous rocks) derived from magma that has solidified at shallow depth in the form of dykes, sills, etc
[C19: from hyp- + -abyssal]


(ˌhɪp əˈbɪs əl, ˌhaɪ pə-)

of or pertaining to any of various minor intrusions of igneous rock, as dikes and sills, that have crystallized at a moderate depth below the surface.


Describes rock that has solidified as an intrusion before reaching the Earth’s surface.
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References in periodicals archive ?
Base and precious metal mineralization is hosted by felsic volcanic rocks, which are in turn crosscut by hypabyssal intrusions, associated with a local paleovolcanic centre.
Ordovician volcanic and hypabyssal rocks in the central and southern Miramichi Highlands: their tectonic setting and relationship to contemporary volcanic rocks in northern New Brunswick.
At La Pedriza, hypabyssal rocks, most prominently microdiorite/aplites and granitic porphyry constitute dikes running inside the granitic rock matrix in an E-W direction.
Geophysical results infer the Groundhog Project lies along the Northeast margin of the large Cretaceous granodiorite Kaskanak batholith and is intersected by a north-northeast-trending corridor of distinctive co-magmatic hypabyssal intrusives.
The lithology of the area consists of greenschists, mica schists, quartzites, hornblende schists, amphibolites, garnet-amphibolites, serpentinites and porphyritic hypabyssal rocks with andesitic to dacitic composition (Figure 1).
Following Dickinson (2006), the term "microphanerite" here covers plutonic and hypabyssal lithic fragments.
These rocks have textures and compositions similar to those of their volcanic equivalents and might be the hypabyssal parts of the komanitic volcanic suites (Arndt et al.
The basement of the graben and the fabric of the hills that surround it consist essentially of plutonic and hypabyssal Paleozoic rocks.
1987) Petrology of the alkalic hypabyssal and volcanic rocks at Cripple Creek, Colorado.
Francois Mountains Complex regardless of inferred mode or depth of crystallization (volcanic phenocryst versus volcanic matrix versus hypabyssal ring pluton versus subvolcanic massif) or crystallization age (1.
Approximately 30 kimberlite occurrences have been identified in the district, including the larger, upper-level diatreme facies such as at Sloan and Kelsey Lake, lower-level diatreme to root zone intrusions, such as at Nix and Moen; and hypabyssal dikes such as George Creek.