Document Type : Original Research Paper

Authors

1 Exploration Directorate of National Iranian Oil Company

2 Department of Geology, Teacher Training University, Tehran, Iran.

Abstract

The Kazhdomi and Sarvak Formations (Bangestan Group) are mainly composed of carbonate rocks. In order to study facies, depositional environments and sequence stratigrphy of these formations in the northwest of FarsProvince, 4 stratigraphic sections including Namak Kangan, Khartang, Khormonj (Coastal Fars) and Shah neshin (Sub-coastal Fars) have been studied.
 Carbonate rocks of the Kazhdomi and Sarvak Formations have been deposited in tidal flat (A), lagoon (B), barrier (C) and open marine (D) facies belts. The sandstone facies of the Kazhdomi Formation (Sandstone tongues equivalent to Burgan Sandstone) are quartzarenite, which were probably deposited in a beach environment. Facies analysis and comparison with modern and ancient environments indicate that the Kazhdomi and Sarvak Formations were deposited in a ramp platform.
Sequence stratigraphy of the Bangestan Group in the study area indicate that the Kazhdomi Formation (except for Namak Kangan, which consists of one depositional sequence) include two depositional sequences (sequences 1 and 2) of early to late Albian age. The Sarvak Formation consists of one depositional sequence in Namak Kangan (sequence 3) and four sequences (sequences 3 to 6) of late Albian to Turonian age in other sections.The lower contact of sequence 1, the lower contact of sequence 2 in Namak Kangan and the lower and upper contacts of sequence 6 are type 1 unconformity (SB1) but the contact of other sequences are type 2 unconformity (SB2).

Keywords

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