Oxygen Isotope Composition of the Silicate Minerals and

The olivine and chromitite δ18Oolivine/chromite and δ18Omelt values point out these minerals and melt isotopic compositions similar to mantle values and rich heavy stable isotopes The highest δ18Ochromite isotopic composition values indicate that as the heavy isotope in the melt increases the concentration in the mineral increases

High pressure minerals De Gruyter

This article is dedicated to the occurrence relevance and structure of minerals whose formation involves high pressure This includes minerals that occur in the interior of the Earth as well as minerals that are found in shock metamorphized meteorites and terrestrial impactites I discuss the chemical and physical reasons that render the definition of high pressure minerals

Melting Point Introduction Example Pressure and its Effect

Now that you understand what is melting point here is a look at how pressure affects melting points Pressure and its Effect on Melting Point In most cases increased pressure increases the melting point for a material This means that under high pressure conditions you would need to apply more heat to cause a material to melt

Geochemical characteristics of mineral inclusions in the

2 32 ABSTRACT 33 The Luobusa chromitite and ophiolite present a captivating geological feature 34 marked by peculiar mineralogical and geochemical characteristics Abundant 35 platinum group minerals PGM base metal sulfides BMS and PGE sulfides and 36 alloys in the chromitite unveil a multi stage genesis encompassing partial mantle 37

Chromitite layers require the existence of large long lived

Therefore an enormous volume of melt >1 00 000 km3 24 25 must have been involved in the generation of all the Bushveld chromitite layers with half of this melt being expelled from the magma

Textural Evidence for the Chromite Oversaturated

Short Communication Textural Evidence for the Chromite Oversaturated Character of the Melt Involved in Podiform Chromitite Formation Betchaida D Payot 1 2 Shoji Arai 1 Rodolfo A Tamayo Jr† 2 and Graciano P Yumul Jr3 1Department of Earth Sciences Kanazawa University Kakuma Ishikawa 920 1192 Japan 2National Institute of Geological

Genesis of silicate exsolution lamellae in chromite of the

X ray elemental mapping of an acicular inclusion in Fig 1 d shows that the inclusion is rich in Si and Ca Fig 1 g A typical energy dispersive X ray spectrum by TEM reveals a composition typical of diopside CaMgSi 2 O 6 Fig 1 h The TEM analyses of the needle like grains show both crystalline and amorphous varieties Fig 2 A selected area

Formation and modification of chromitites in the mantle

Podiform chromitites have long supplied us with unrivaled information on various mantle processes including the peridotite magma reaction deep seated magmatic evolution and mantle recent discovery of ultrahigh pressure UHP chromitites not only sheds light on a different aspect of podiform chromitites but also changes our understanding of the

Origin of podiform chromitite a new model based on the

Podiform chromitites have been interpreted as the result of melt rock reaction and related melt mixing in upper mantle sections of the discovery of ultrahigh pressure UHP minerals especially diamond and coesite in many podiform chromitites and host peridotites raises fundamental questions about the validity of this Chromitites in the

The Melting Point of Germanium as a Function of Pressure

Molecular dynamics calculations of the thermal expansion properties and melting points of Si and Ge Journal of Physics Condensed Matter 2006 18 13 Parameters in the Simon Equation Relating Pressure and Melting Temperature Reviews of Modern Physics 1963 35 2 400 413

Melting point vs pressure Physics Stack Exchange

"The melting point of the same substance changes under different pressure But it can change in two different manner" There are 2 different ways it can change $ 1 $ For higher pressure the melting point will be lower Like water $ 2 $ For higher pressure the melting point will be higher Also

High pressure experiments provide insights into the Mantle

2 Subduction recycling model low pressure chromitite was subducted to the MTZ as part of a slab system; the chromite and its host dunite/harzburgite then ascended to appear at a spreading center as a mantle diapir driven by mantle convection or slab rollback Arai 2013 McGowan et al 2015 Griffin et al 2016

Role of melt injection and mixing in the formation of chromitite

Chromitite occurs in many Archean anorthosite complexes The Neoarchean Sittampundi Anorthosite Complex SAC in southern India is composed of mainly amphibole rich anorthosite minor gabbro

Genesis and high pressure evolution of the Köyceğiz

A genetic model or scenario of the formation and evolution of the Köyceğiz chromitites may include i early crystallization of chromitite from boninitic melts derived from a hydrated mantle wedge above a subducting slab and during peridotite melt reaction Robertson 2002 Uysal et al 2007 Xiong et al 2018a ii clinopyroxene

PDF Petrogenesis of the chromitite body from

occurrence of the dunite and chromitite indicates that the reaction took place along melt conduits ‹fractures less than 200m in width Podiform chromitites were formed only

Chromitites of the Kraka ophiolite South Urals Russia

The paper describes disseminated tabular podiform massive and transitional chromitite deposits from a mantle section of the Kraka ophiolite massif South Urals Russia The chromitite is hosted by dunite with no correlation between their size and quality and the size of the dunite bodies Thick dunite bodies mostly host disseminated fine grained banded chromitite;

Massive chromitite layers of the Bushveld Complex South Africa…

Two of these articles discussed the Bushveld Complex whereas eight articles focused on podiform chromitite Some of the focus points and/or findings presented in these papers are summarized as

PDF A new model for chromitite formation in ophiolites

Chromites have an important economic value; their value is even more important since they are often associated with enrichments in platinum group minerals PGM

Evaluation of PGE Liberation and Chromium Isolation in a

Fusion of the Chromitite Concentrate Using NH 4 H 2 PO 4 / NH 4 2 HPO 4 Flux The next step in this study was to evaluated ammonium phosphate salts as possible fluxes The rationale was these salts are chemically similar to the sodium salt and have compatible melting points but do not introduce Na into the reaction mixture

Microstructural Insights into the Evolution of Ophiolitic

The podiform chromitite found within the Luobusha ophiolite comprises characteristic nodules and massive chromitites However the exact origin of these formations remains a topic of ongoing debate In this study the microstructures of olivine and chromite are investigated to unravel their formation processes and shed light on the associated geodynamic

Ultra high pressure inclusion in Archean ophiolitic podiform chromitite

Ophiolites and ophiolitic mlanges are both tectonic indicators of sutures where oceans have closed through subduction and collision Festa et al 2019 Kusky et al 2018 Kusky 2020 The Zunhua ophiolitic mlange is a key component of the Central Taihang Orogenic Belt COB that separates the Eastern and Western Blocks of the NCC Fig 1 a;