Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Petrography and petrology of the metamorphic Aureole of the Kamtal intrusive Body

Document Type : Original Research Paper

Authors
Ali Darvishzadeh
Mir Saleh Mirmohammadi
Geology Department, Science Faculty, Tehran University, Tehran, Iran
Abstract
The intrusion of Kamtal Igneous body into a series of Late Cretaceous rocks with a varied lithologies, has brought about extensive, as well as considerable thickness of contact metamorphism (aureole metamorphism). Petrographic investigation, accompanied with the XRD analysis of various rock- samples demonstrated that alblite epidote facies grade of metamorphism (low- grade) occurred away from the igneous marginal zones, whereas, pyroxene- hornfels facies (high- grade) took place close to the marginal areas.
     With regards to the mineralogical paragenesis of the samples, the temperature pressure condition for the albite- epidote facies of metamorphic aureole are estimated at 400⁰C - 300⁰C under the pressure of 1.5-2 Kbr. While, for corresponding pressure for pyroxene- hornfels facies is 600⁰C to 750⁰C. Presence of garnets with varying compositions in the garnetites and the late- stage epidote- bearing garnet veins, is indicative of changing composition in hydrothermal fluids during the intrusion and evolution of Kamtal Igneous body.
Keywords
Kamtal intrusive Body, metamorphic Aureole

Subjects

 
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Scientific Quarterly Journal of Geosciences
Volume 5, 17-18
Autumn & Winter 1996, Vol. 5, No. 17-18
Winter 1996
Pages 2-9