Abstract
A body of dolomite marble near Chotěboř was found in migmatized biotite paragneiss of the Moldanubicum directly on the border with migmatites/orthogneisses of the Kutná Hora Crystalline Complex. The area underwent significant tectonic reworking of rocks along the Přibyslav mylonite zone. Therefore, only small relics of early prograde HT/LP metamorphism at T > 650 - 700 °C were preserved in this marble. They are represented by the assemblage dolomite+calcite+forsterite+Zn-spinel+clinohumite ±Ba-phlogopite and rare baddeleyite. This mineral assemblage underwent strong low-temperature retrograde metamorphism (< 400 - 300 °C) under the conditions of high H2O activity (XCO2 < 0.10 - 0.15), which was manifested by almost complete serpentinization of forsterite. Partial alteration of clinohumite produced serpentine with numerous inclusions of a TiO2-mineral and rare sphalerite. The examined serpentine marble (ophicalcite) is lithologically and mineralogically similar to the dolomite marbles found in the Strážek Moldanubicum.
Publisher
Bulletin Mineralogie Petrologie
Subject
Economic Geology,Geochemistry and Petrology,Geology
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