Intrusive rocks

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Related to Intrusive rocks: Volcanic rocks
(Geol.) rocks which have been forced, while in a plastic or melted state, into the cavities or between the cracks or layers of other rocks. The term is sometimes used as equivalent to plutonic rocks. It is then contrasted with effusive or volcanic rocks.

See also: Intrusive

References in periodicals archive ?
The significance of this information is that prior exploration programs at Yauricocha have not typically assayed the intrusive rocks, as the mineralization was considered to occur in the contact of the intrusive and the volcanics.
The confidence in the resource potential is driven not solely by the presence and extent of the quartz roscoelite mineralisation, but also by the similar style and age of intrusive rocks, similar host rocks, and a similar structural setting.
32nT to -225nT, characterised by longer wavelength anomaly, while the shallower sources ranged from 0 23km to 0 76km, anomaly values ranging from -10nT to 20nT, characterised by short wavelength anomaly The shallower sources probably depicted depths to pre-Cambrian basement or near surface basic igneous intrusive rocks (such as basalt flows and dolerites) and/or low-lying river valleys.
Mineralization is hosted by strongly foliated diorite intrusive rocks, emplaced along a regional scale shear zone and in contact with the Coastal Batholith.
The lithology of intrusive rocks consists of gabbro, diorite, quartz diorite, granodiorite, biotite granite and leucogranite.
In the Gayot Lake area, Virginia Gold Mines and partner BHP Minerals discovered several Ni-Cu-PGE showings in komatiitic lavas and ultramafic intrusive rocks of the Venus volcano-sedimentary belt.
Intrusive rocks of the Coldwell Complex revealed high grade mineral zones of copper, gold, palladium and platinum and other metals.
They are geologically favorable to PGMs, as they include mafic intrusive rocks of the River Valley Intrusive and Nipissing Diabase.
The Kalabak license is underlain by Tertiary intermediate to felsic volcanic and intrusive rocks (Fig.
Around the town of Marathon, the intrusive rocks of the Coldwell Complex has become an active area for companies finding good numbers for copper, nickel and platinum group metals (PGMs).