Alteration Types In Granitic Rocks

They have two different origins.

Alteration types in granitic rocks. It corresponds to the outcropping of the lower part of the fractured horizon of an alteration profile. Wyns crystalline rocks or hard rocks are rocks that are generally ancient formed at great depth at several tens of kilometres. Features of feldspar alteration in the granitic rocks are similar to those encountered in feldspathic sandstones and should hence be considered in studies on diagenetic changes of siliciclastic. Bradley dalton winfield g.

Mineral alteration is essentially governed by the laws of thermodynamics related to energy conservation relevant to environmental conditions often in presence of catalysts the most common and influential being water h 2 o. Present study aims to understand the nature of. The degree and scales of time in which. And zoning of hydrothermally altered rock the age and type of mineralization and hydrothermal alteration and trends or patterns of veins and faults.

Hydrothermal alteration and related solid and aqueous phase geochemical signatures by dana j. Mineral alteration refers to the various natural processes that alter a mineral s chemical composition or crystallography. Hydrothermal alteration can be isochemical like meta morphism and dominated by mineralogical changes or it can be metasomatic and result in significant addition or removal of elements. Alteration is defined as any alteration of rocks or minerals by the reaction of hydrothermal fluid with preexisting solid phases.

The chemical and textural characterization of various types of plagioclase alterations allows elucidation of the granitic hydrothermal systems. This alteration grades into the potassic type by increasing amounts of k ak k feldspar and or biotite and into the argillic type by increasing amounts of h ah clay minerals. Phyllic alteration is associated with porphyry cu deposits but also with mesothermal precious metal ores and volcanogenic massive sulfide deposits in felsic rocks. About 10 types are being named as under though numerous permutations and combinations often tend to produce mixed variables.