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The significance of tridymite in igneous and metamorphic petrogenesis

Published online by Cambridge University Press:  14 March 2018

George P. Black
George P. Black*
Affiliation:
Grant Institute of Geology, University of Edinburgh
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Extract

Physico-Chemical data clearly show that the presence of tridymite in a rock indicates the prevalence not only of high temperatures, but also of relatively low pressures during the formation of that rock. Whereas many authors (e.g. Shand, 1927; Larsen, 1936) have used tridymite as an indicator of temperature, the importance of tridymite as an indicator of pressure has been largely overlooked.

Although the presence of tridymite is by itself sufficient to enable the pressure, and hence the depth, at which a rock formed to be estimated within certain limits, the presence of tridymite in association with some other pressure-or temperature-indicating mineral allows much closer limits to be set.

Type
Research Article
Information
Mineralogical magazine and journal of the Mineralogical Society , Volume 30 , Issue 227 , December 1954 , pp. 518 - 524
Copyright
Copyright © 1954, The Mineralogical Society

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References

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