Microfacies and paleoenvironmental analysis of lower to middle eocene sediments, west of Tafresh

Abstract

M.Y. Rad, H. Noroozpour

Lower to Middle Eocene outcrops of Naqusan section, located in the northwest of Tafresh, with a thickness of 110 meters chiefly encompasses sandy-marly limestone and tuff along with a low percentage of sedimentary rocks such as sandstone. Microfacies studies led to the identification of six carbonate microfacies related to three facies belts (shoal, lagoon and open marine). The general palaeogeographic context of this system was a marginal marine shelf setting with an inner platform that was very flat, ramp-like, with little topography but with local depressions. Regarding extensive presence of large benthic foraminifera and some algae, the studied section probably have been deposited in tropical waters.

Keywords: Paleoenvironment; eocene; naqusan; Tafresh

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