Intrusive Rocks


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Related to Intrusive Rocks: Volcanic rocks

Intrusive Rocks

 

plutonic rocks, igneous rocks formed as a result of magma solidification deep in the rock mass of the earth’s crust. Intrusive rocks are contrasted with effusive rocks, which are rocks formed from the magma that flowed out and hardened on the surface of the earth as the lava of volcanoes.

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Since the southern part of the area lies on the sediment-basement boundary (part of the Cretaceous Benue Trough's northern margin), the causative sources were considered to be deeper-seated intra-basement basic intrusive rock bodies.
Surface mapping by our geological crew has identified copper oxide mineralization and the same alteration assemblage elsewhere on the Zafranal Property in deformed intrusive rocks similar to those which host Victoria.
This discovery highlighted a new type of setting for nickel mineralization in ultramafic intrusive rocks of the region, where Ni-Cu-Co-PGE deposits were already known to be associated with komatiitic rocks in greenstone belts.
This is followed by a segment highlighting PGE mineralization concentrated as a result of the physicochemical interaction of intrusive rocks and host rock.
At the San Jose "cuerpo," La Chilca and Shahuindo variably altered intrusive rocks contain relict phenocrysts of quartz, plagioclase, and biotite.
Underlying geology within the property area consists of intermediate to felsic intrusive rocks that have been cross-cut by a series of quartz veins.
These claims cover a tight, east to south flexure in the Opinaca-La Grande contact zone, and are underlain mainly by basalt meta-volcanic rocks in contact with tonalite intrusive rocks.
Recently, YTC Resources reported an intercept of 50m of "porphyry style alteration in intrusive rocks with associated weak copper mineralisation" at Mullahgalah (Figure 1) on a prominent magnetic anomaly 15km north of Thomson's Byrock Project.
They have a good handle on the properties of the River Valley Intrusive's 12-km contact and now are working to expand away from the line into the intrusive rocks.
The Kiwi property consists of 32 units (668 ha) located 25km west of the North Canol Road which overlie high-grade gold occurrences associated with intrusive rocks in contact with silicified shales with controlling east-west dilational structural features.
The geological setting of the project area is similar to the prolific Sadiola and Loulo gold districts in adjacent Mali, being underlain by highly prospective, Birimian-aged metasedimentary, volcanic and intrusive rocks along a seven-kilometre strike length of the Senegal-Mali Shear Zone.
The recognition of the geological contact between the intrusive rocks and the sedimentary rocks has important implications for regional prospecting.