Search results
Results From The WOW.Com Content Network
The name diorite (from Ancient Greek διορίζειν, "to distinguish") was first applied to the rock by René Just Haüy [10] on account of its characteristic, easily identifiable large crystals of hornblende. [4] Dioritoids form a family of rock types similar to diorite, such as monzodiorite, quartz diorite, or nepheline-bearing diorite ...
In some compositions, at high pressures without water crystallization of enstatite is favored, but in the presence of water at high pressures, olivine is favored. [ 12 ] Granitic magmas provide additional examples of how melts of generally similar composition and temperature, but at different pressure, may crystallize different minerals.
Hornblende diorite from the Henry Mountains, Utah, US. Hornblende is a common constituent of many igneous and metamorphic rocks such as granite, syenite, diorite, gabbro, basalt, andesite, gneiss, and schist. It crystallizes in preference to pyroxene minerals from cooler magma that is richer in silica and water. [13]
Stiff diagrams can be used: 1) to help visualize ionically related waters from which a flow path can be determined, or; 2) if the flow path is known, to show how the ionic composition of a water body changes over space and/or time. Example of a Stiff diagram. A typical Stiff diagram is shown in the figure (right).
QAPF diagram for classification of plutonic rocks. A QAPF diagram is a doubled-triangle plot diagram used to classify intrusive igneous rocks based on their mineralogy.The acronym QAPF stands for "Quartz, Alkali feldspar, Plagioclase, Feldspathoid (Foid)", which are the four mineral groups used for classification in a QAPF diagram.
The name comes from two related rocks to which granodiorite is an intermediate: granite and diorite. The gran-root comes from the Latin grānum for "grain", an English language derivative. Diorite is named after the contrasting colors of the rock.
Euhedral pyrite crystals A subhedral sample showing sharp to anhedral pyrargyrite crystals. Euhedral and anhedral are terms used to describe opposite properties in the formation of crystals . Euhedral (also known as idiomorphic or automorphic ) crystals are those that are well-formed, with sharp, easily recognised faces .
A petrographic microscope is a type of optical microscope used to identify rocks and minerals in thin sections. The microscope is used in optical mineralogy and petrography, a branch of petrology which focuses on detailed descriptions of rocks. The method includes aspects of polarized light microscopy (PLM).