Publication Date:
2018-01-13
Description:
This study presents a new approach to geobarometry by combining fluid inclusion and clumped isotope (Δ 47 ) thermometry on carbonate minerals. The offset between homogenization temperatures of primary fluid inclusions with known composition and Δ 47 temperatures of the host mineral allows a direct estimation of the fluid pressure at the time of carbonate crystallization. This new approach is illustrated via hydrothermal dolomite samples from the Variscan foreland fold-and-thrust belt in northern Spain. Clumped isotope analyses yield crystallization temperatures (107–168 °C) which are higher than homogenization temperatures in corresponding samples (95–145 °C). The calculated pressure values suggest that dolomitizing fluids were overpressured during formation of zebra dolomite textures, whereas lower pressures are obtained for dolomite cement from breccia textures. This new approach to geobarometry opens up the possibility of estimating the pressure of carbonate crystallization and has potential applications in diagenesis, basin analysis, ore geology and tectonics. This article is protected by copyright. All rights reserved.
Print ISSN:
0954-4879
Electronic ISSN:
1365-3121
Topics:
Geosciences
