SUMMARY
Characteristics of
inclusions and forming temperature of granitoids,
tin-wolfram and gold ores in Việt Nam
Hoàng Sao
Inclusions are formed in the crystallizing process of minerals. They
have been subdivided into 3 groups: solid, gas and liquid-mixed inclusions.
Based on the forming time of inclusions in comparision to containing them
minerals, they can be subdivided into: primary, primary-secondary and secondary
inclusions. At present, the methods of homogenization, cryometry, decrepitation
and chemico-physical method have been used in the study on inclusion types,
aiming to determine the quantitative chemico-physical parameters (temperature,
composition, pressure) of the mineral-forming environment, basing on this one
can interprete precisely many geological problems.
The study on different types of inclusions in quartz of granitoids of
the Trúc Khê - Núi Điệng and Thiện Kế massifs and in veins of tin-wolfram, gold
ores in Việt
- Granitoids of the Trúc Khê - Núi Điệng and Thiện Kế massifs contain
primary crystallyzed and glassy inclusions having the forming temperature of
from 600-700 to 980°C;
- Inclusions within quartz of tin-wolfram ores in Việt Nam is abundant
and diversified, usually composed of 5 types of primary inclusions: gas,
gas-liquid, polyphase, liquid-carbonic and liquid-gas, formed in two stages:
pneumatogene-hydrothermal (300-500°C) at the pressure of 650-1300 At, and
hydrothermal in high-medium temperature (145-390°C) at the pressure of 750-1210
At. The highly concentrated tin-wolfram ores, usually of industrial
significance, were formed in the hydrothermal stage of high-medium temperature
(145-390°C);
- Inclusions within quartz of primary gold type in Việt
Ngày
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Người biên tập: Phan Trường Thị