Original paper
Palaeoenvironment, sequence stratigraphy and palaeogeography of the Lower Cretaceous deposits of Mehdi Abad, Yazd Block, Central Iran
Safaei, Mohammad; Mahboubi, Asadollah; Modabberi, Soroush; Moussavi-Harami, Reza
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen Band 295 Heft 1 (2020), p. 61 - 89
72 references
published: Jan 29, 2020
manuscript accepted: Dec 3, 2019
manuscript received: Jul 4, 2019
ArtNo. ESP155029501005, Price: 29.00 €
Abstract
Four Lower Cretaceous sections in the southern Yazd Block were measured and studied to interpret the palaeoenvironments, synsedimentary tectonics, and sequence stratigraphy. The Early Cretaceous sedimentary record of this block, consisting of the Sangestan, Taft, Abkuh, and Darreh Zanjir formations, was mainly influenced by synsedimentary tectonic activities in a tectonically unstable basin. Field observations and laboratory studies were used to identify lithofacies and microfacies, based on which six depositional environments were identified: upper coastal plain (alluvial fans), shore, tidal flat, lagoon, shoal, and open marine. A carbonate-siliciclastic shallow platform including an alluvial-coastal plain and an inner platform is suggested for the depositional environment of the Sangestan Formation. The depth of the overall shallow sedimentary basin of Sangestan Formation increases from west to east and deposition was controlled by long-term sea-level changes. A carbonate platform consisting of inner and outer parts, including tidal flat, lagoon, open marine belts, is suggested for the depositional environment of the Taft and Abkuh formations, while the Darreh Zanjir Formation accumulated in a deep basin. The predominant facies demonstrate an overall transgression-regression cycle (the 2rd order cycle) during the depositional time of these formations in the southern Yazd Block.
Keywords
Central Iran • facies • Lower Cretaceous • palaeoenvironments • sequence stratigraphy • Yazd Block • Mehdi Abad