Lamprophyre - Wikipedia
Minette (a type of lamprophyre), from Jáchymov in the Czech Republic. Lamprophyres (from Ancient Greek λαμπρός (lamprós) 'bright' and φύρω (phúrō) 'to mix') are uncommon, small-volume ultrapotassic igneous rocks primarily occurring as dikes, lopoliths, laccoliths, stocks, and small intrusions.
Lamprophyres - ALEX STREKEISEN
A rare variety of ultramafic lamprophyre consisting of combinations of forsteritic olivine, diopsidic pyroxenes, various amphiboles and phlogopite in a matrix of similar minerals with abundant primary carbonates and feldspathoids, often with minor perovskite, but little or no melilite.
Lamprophyre | Properties, Composition and Formation - Geology …
2019年5月11日 · Lamprophyre is ultrapotassic igneous rock that is occurring as dikes, lopoliths, loccoliths, stocks and small intrussion. It is alkaline silica-undersaturated mafic or ultramafic rocks with high magnesium oxide, >3% potassium oxide, …
Lamprophyre | Igneous, Mafic & Ultramafic | Britannica
lamprophyre, any of a group of dark gray to black intrusive igneous rocks that generally occur as dikes (tabular bodies inserted in fissures). Such rocks are characterized by a porphyritic texture in which large crystals (phenocrysts) of dark, iron-magnesium (mafic) minerals are enclosed in a fine-grained to dense matrix (groundmass).
Lamprophyre - an overview | ScienceDirect Topics
Lamprophyre is defined as a type of porphyritic dyke rock characterized by phenocrysts of solely mafic minerals, such as biotite or amphibole, with feldspars and/or feldspathoids limited to the groundmass.
Lamprophyre - chemgeo.uni-jena.de
Lamprophyre is an unusual group of dark, igneous rocks, which due to their chemical composition belong to the alkali rocks. The name "lamprophyre" comes from the Greek and means "bright" or "shiny", referring to the crystal faces of amphibole and …
The nature and origin of lamprophyres: some definitions, distinctions ...
1977年9月1日 · Lamprophyres are porphyritic dyke-rocks, readily recognisable in the field, which seemed to have become enveloped in petrological mystery because of their scattered and often contradictory literature.
The nature and origin of lamprophyres: an overview
Lamprophyres are ‘alkaline rocks’ because they carry high alkalis at a given percentage of SiO 2, together with one or more of normative ne, lc or ac, modal foids, and Na-K-Ti-rich amphiboles or pyroxenes. They reach higher whole-rock H 2 O, CO 2, …
The term 'lamprophyre' was coined by GUmbel (1874), making it one of petrography's oldest; in fact it predates such fashionable wunderkinden as komatiite and ophiolite by a full century.
Lamprophyre - chemeurope.com
Lamprophyres are uncommon, small volume ultrapotassic igneous rocks primarily occurring as dikes, lopoliths, laccoliths, stocks and small intrusions. They are alkaline silica-undersaturated, ultramafic rocks with high magnesium oxide, >3% potassium oxide, high sodium oxide and high nickel and chromium.