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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8 Km) northeast of Cretaceous quartz/granite porphyry intrusive rocks historically explored for molybdenum and copper in the Spruce Mountain Mining District.
Gold mineralization is found in skarn material associated with intrusive rocks and within veins hosted by both intrusive and sedimentary rocks.
One of the areas of interest, the El Oso project area, is located over Cretaceous and Tertiary age volcanic and intrusive rocks.
The Property is underlain by rocks of the Proterozoic Wollaston Domain comprising ortho- and paragneisses, including Archean gneissic domes (basement) and minor younger intrusive rocks including abundant pegmatite bodies.
The geological setting of the La Reforma Mine is complex and consists of Mesozoic age, carbonate rich, meta-sedimentary and meta-volcanic rocks which are intruded by several phases of intrusive rocks from Cretaceous to Miocene time.
Recognition of these intrusive bodies at Bailey Hills was previously hampered by post-mineralization volcanic cover rocks, but geophysical surveys have identified intrusive rocks and numerous high angle faults underlying the claim area.
Retrograded QSP altered granitic intrusive rocks with molybdenite-quartz stringers persisted down to 258 m, where a 3 m wide fault zone was encountered, perhaps at the contact with a large intrusive body.
The intrusive rocks are also mineralized with disseminated pyrite replacing biotite and pyrite and bismuthinite in quartz-carbonate veinlets.
This anomaly appears to be open to the east and west and coincides with a zone of weathered monzonitic intrusive rocks that differ markedly from the intrusive rocks elsewhere on the property.
Gold-silver mineralization occurs in veins and stockwork hosted in felsic tuffs which overly granitic intrusive rocks.
The Twilight Zone breccia and San Pedro breccia are mineralized zones within and adjacent to granodiorite igneous rocks, thus there is an important relationship between the sedimentary rocks, veins, breccias and intrusive rocks at Vianey Mine.
Along Rufin Kreek itself, a several hundred metre square surface area is currently being mined from the alluvial gravels up onto the surrounding hillsides where saprolitic intrusive rocks and quartz veinlets are exposed.