Triangular Plots in Metamorphic Petrology - Tulane University
Thus we have several possibilities for writing the formula for chlorite, and depending on which formula we use, chlorite will plot at different locations on the diagrams. You will explore the possible solid solution ranges in a lab on this topic.
14 Metamorphism of Pelitic Rocks – Open Petrology - OpenGeology
Figure 14.1 shows the most important index minerals from low grade to high: chlorite, muscovite, biotite, garnet, staurolite, kyanite, and sillimanite. The sequence of minerals depicted in Figure 14.1 is typical for metapelites undergoing Barrovian metamorphism. But there is variation depending on rock composition.
Metamorphic Reactions - Tulane University
In the diagram to the left, representing the lowest grade, a rock with composition x consists of a relatively Mg-poor biotite + Mg-poor chlorite. As metamorphic grade increases to the middle diagram, the three phase triangle - Garnet - Biotite - Chlorite has shifted, with all three phases becoming more Mg-rich, and now composition x lies inside ...
Serpentines, talc, chlorites, and their high-pressure phase transitions ...
2015年5月1日 · We present a Raman spectroscopic study of serpentines, chlorites, and talc at ambient conditions and, for selected samples, at high pressure. For lizardite and antigorite, experiments at simultaneous high P and T were used to bracket phase equilibrium curves.
8.6.1: Metamorphosed Pelitic Rocks (Metapelites)
2022年8月28日 · Metapelites derive from the metamorphism of shale and other clay-rich sediments. When metamorphosed, dehydration reactions change clay minerals into new minerals containing less H 2 O. At low grade this leads to the formation of chlorite and muscovite. At higher grade, biotite forms.
Chlorite - Geology is the Way
Chlorite represents a common alteration phase of many igneous and metamorphic minerals. Typical examples are chlorite pseudomorphs after biotite and garnet. Chlorite is also a product of low-temperature hydrothermal circulation and can be found as veins, Airedales, and in hydrothermally-altered rocks.
Compatibility diagram - Wikipedia
In metamorphic geology, a compatibility diagram shows how the mineral assemblage of a metamorphic rock in thermodynamic equilibrium varies with composition at a fixed temperature and pressure. Compatibility diagrams provide an excellent way to analyze how variations in the rock's composition affect the mineral paragenesis that develops in a ...
Chlorite zone – Greenschist Facies • Based on the information provided in Figure 28.1, what are the common metamorphic mineral assemblages for pelites within the chlorite zone of the greenschist facies? • Chlorite + Phengitic Muscovite + Quartz • Chlorite + K-feldspar + Quartz (only stable for low Al-bearing rocks)
(a) Compositional diagram for rock-forming chlorites in the Al þ ...
Given the lack of phase modelling, empirical chlorite geothermometer, based on tetrahedral Al content in chlorite (Yavuz et al., 2015), is used to estimate the final equilibration conditions...
Mineral composition of chlorites of MG: a, FeO?MgO?Al2O3 …
In the Malanjkhand Granitoid (MG), chlorite occurs in micro-domain along with mineral assemblage biotite, hornblende, quartz, K-feldspar and plagioclase. Chloritization of biotite is the most...