University Of Tasmania
Browse
Download file
Download file
1/1
2 files

Water- and boron-rich melt inclusions in quartz from the Malkhan Pegmatite, Transbaikalia, Russia

Download all (1.81 MB)
journal contribution
posted on 2023-05-17, 15:33 authored by Thomas, R, Paul DavidsonPaul Davidson, Badanina, E
In this paper we show that the pegmatite-forming processes responsible for the formation of the Malkhan pegmatites started at magmatic temperatures around 720 °C. The primary melts or supercritical fluids were very water- and boron-rich (maximum values of about 10% (g/g) B2O3) and over the temperature interval from 720 to 600 °C formed a pseudobinary solvus, indicated by the coexistence of two types of primary melt inclusions (type-A and type-B) representing a pair of conjugate melts. Due to the high water and boron concentration the pegmatite-forming melts are metastable and can be characterized either as genuine melts or silicate-rich fluids. This statement is underscored by Raman spectroscopic studies. This study suggested that the gel state proposed by some authors cannot represent the main stage of the pegmatite-forming processes in the Malkhan pegmatites, and probably in all others. However there are points in the evolution of the pegmatites where the gel- or gel-like state has left traces in form of real gel inclusions in some mineral in the Malkhan pegmatite, however only in a late, fluid dominated stage.

Funding

Australian Research Council

AMIRA International Ltd

ARC C of E Industry Partner $ to be allocated

Anglo American Exploration Philippines Inc

AngloGold Ashanti Australia Limited

Australian National University

BHP Billiton Ltd

Barrick (Australia Pacific) PTY Limited

CSIRO Earth Science & Resource Engineering

Mineral Resources Tasmania

Minerals Council of Australia

Newcrest Mining Limited

Newmont Australia Ltd

Oz Minerals Australia Limited

Rio Tinto Exploration

St Barbara Limited

Teck Cominco Limited

University of Melbourne

University of Queensland

Zinifex Australia Ltd

History

Publication title

Minerals

Issue

4

Pagination

435-458

ISSN

2075-163X

Department/School

School of Natural Sciences

Publisher

MDPIAG - Open Access Publishing

Place of publication

Postfach, Basel, 4005 Switzerland

Rights statement

Licensed under Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/)

Repository Status

  • Open

Socio-economic Objectives

Expanding knowledge in the earth sciences