A comparative study of diffusion profiles in Himalayan and Dalradian garnets: constraints on diffusion data and the relative duration of the metamorphic events
Article Abstract:
Researchers have been able to calculate low-temperature cation interdiffusion rates from natural garnets by assessing and modelling the extent to which initial cation growth profiles grow diffusively modified during peak metamorphism. It was also possible to show how relative constraints can be placed on the durations of peak metamorphism experienced by garnets from kyanite-bearing metapelite samples from the High Himalayan Cyrstalline Series, Zanskar, India, and by Scottish Dalradian garnets. It was concluded that the duration of metamorphism experienced by Dalradian samples lasted between 10 and 20 times longer than that of the Himalayan samples.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1997
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Pressure-temperature paths from P-T pseudosections and zoned garnets: potential, limitations and examples from the Zanskar Himalaya, NW India
Article Abstract:
An understanding of the tectonic mechanism of orogenic belts is furthered by ascertaining the equilibration pressures (P) and temperatures (T) of metamorphic rocks. A pseudosection approach is one way to obtain a P-T path for rocks. A new study investigates the potential and limitations of the pseudosection method by applying it to metamorphic rocks from the Himalaya. It is shown that the approach, while appearing to reliably model the P-T paths of garnet core growth, is less useful in predicting compositions outside the core.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1998
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Obtaining equilibrium oxygen isotope fractionations from rocks: theory and examples
Article Abstract:
Research shows that slowly cooled high-temperature metamorphic and plutonic rocks fail to retain equilibrium oxygen isotope fractionations. A new approach uses models of retrograde diffusion exchange and prograde reaction histories to retrieve equilibrium isotope fractionations from natural rocks. New analyses from 32 natural amphibolite-facies schists are used to demonstrate the viability and limitations of the proposed approach.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1998
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