Igneous
111Schist — The schists constitute a group of medium grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn out grains to such an… …
112Crust (geology) — Geologic provinces of the world (USGS)   Shield …
113Peridotite — A peridotite is a dense, coarse grained igneous rock, consisting mostly of the minerals olivine and pyroxene. Peridotite is ultramafic and ultrabasic, as the rock contains less than 45% silica. It is high in magnesium, reflecting the high… …
114Quartz monzonite — Igneous Rock Quartz monzonite bedrock from a UGSG drill core at Western Cape Cod, Massachusetts Quartz monzonite (or adamellite) is an intrusive igneous rock that has an approximately equal proportion of orthoclase and …
115Norite — is a mafic intrusive igneous rock composed largely of the calcium rich plagioclase labradorite and hypersthene with olivine. Norite is essentially indistinguishable from gabbro without thin section study under the petrographic microscope. It… …
116Tholeiitic basalt — is an igneous rock, a type of basalt. Like all basalt, the rock type is dominated by clinopyroxene plus plagioclase, with minor iron titanium oxides. [http://micro.magnet.fsu.edu/primer/techniques/polarized/gallery/pages/basalttholeiiticsmall.html… …
117TAS classification — The TAS classification can be used to assign names to many common types of volcanic rocks based upon the relationships between the combined alkali content and the silica content. These chemical parameters are useful, because the relative… …
118Merensky Reef — Mines of the Merensky Reef The Merensky Reef, is a layer of igneous rock in the Bushveld Igneous Complex (BIC) in the Transvaal which together with an underlying layer, the Upper Group 2 Reef (UG2), contains most of the world s known reserves of… …
119Pilot Knob (Austin, Texas) — Pilot Knob is a hill that is part of an extinct volcano located seven miles south of central Austin, Texas near Austin Bergstrom International Airport and McKinney Falls State Park.IntroductionPilot Knob is one of around 75 late Cretaceous Period …
120Lamprophyr — Lamprophyre – vom griechischen λαµπρός (lamprós) = hell, glänzend (in Bezug auf die Kristallflächen von Amphibol und Biotit, die im frisch aufgeschlagenen Zustand hell aufleuchten) und φύρω (phýro) = vermengen, eingeführt durch Carl Wilhelm von… …
