Facies Analysis, Depositional Environment of the Lower Permian Deposits of Chili Formation in Kalmard Block, Eastern Central Iran (Darin Section)

Javad Shahraki,Mahdiyeh Nastooh,Mohammad Javad Javdan,Seyed Mahmood Pahlavan Hashemi,Seyed Mohammad Kalvandi,Mohsen Jami

doi:10.4236/ojg.2015.58049

Abstract

Early Permian deposits in north of Kalmard region recognize with formal group of Khan; they have various features in the different place. This group includes four different formations from lower to the upper part: Chili, Sartakht and Hermez. These formations consist of carbonate rocks. Chili Formation has 104 m, thickness in Darin section and consists of limestone with intermediates of shale and marland sandstone. Lower boundary of this formation is disconformable with Gachal formation. The upper boundary is separated by unconformity from the upper part Sartakht formation according to the lithological characters and microscopic studies, cause identifications of beach, intertidal, open and semi-restricted lagoon, shoals and bar and open marine sub-environ- ments for the Chili Formation. Vertical changes of microfacies and depth changes curve show much more thickness of shoals and bar microfacies, and little thickness of open and semi-re- stricted lagoon and open marine microfacies. Deposits of Chili Formation in Darin section deposited in the gentle gradient Homoclinal ramp in the south of Paleotethys Ocean. Two depositional sequences have been identified in this formation, based on recognized Fusulinid, show age of Sakmarian, which has adaptation with Lower Absaroka III.

Highlights

Central Iran, shaped like a triangle and as one of the major, largest and most complex geological units in Iran, is located in the center of Iran
Darin section has mainly consisted of limestone, sandstone
Darin section is located in the southwestern Tabas and Eastwestern Robatkhan in Kalmard area

Summary

Introduction

Central Iran, shaped like a triangle and as one of the major, largest and most complex geological units in Iran, is located in the center of Iran. The dominant structural pattern of this area is of separate blocks type, separated from each other by deep faults and has distinct characteristics. Kalmard block forms a small part of this area and is located between Kalmard Faults in the east and Naeini Faults in the west [1]-[3]. Chili Formation, composed of sandstone and limestone, is one of the depositional units of lower Permian in Kalmard block and one of the most perfect outcrops of Chili Formation in Darin section. Darin section has mainly consisted of limestone, sandstone. Darin section is located in the southwestern Tabas (at 1:250000 scale) and Eastwestern Robatkhan (at 1:100000 scale) in Kalmard area (eastern central Iran). This section is framed by the geographical coordinates of 33 ̊31'01"N and 56 ̊09'14"E (Figure 1)

Objectives

Methods

Findings

Discussion

Conclusion