Sarvak Reservoir Facies Characteristics in One of the South West Field in Iran

Somayeh Pakparvar,Davood Jahani,Nader Kohansal Ghadimvand

doi:10.4236/ojg.2017.73020

Abstract

Sarvak Formation (Late Albian-Early Turonian) as main reservoir in the field is one of the carbonate units of Bangestan Group in Zagros Basin with average thickness of 640 m. This formation conformably overlays the Kazhdumi Formation while the upper boundary is an erosional unconformity which is covered by Ilam Formation. There is a significant lateral and vertical heterogeneity in the reservoir layers that causes main challenge in reservoir characterization. In this paper, reservoir properties evaluation and construction of depositional model have been done based on lithotype study, sedimentary environment classification, petrophysical interpretations and SeisWorks. Five facies types (lithotypes) in the Sarvak Formation with particular rock properties are identified in 8 wells and 200 thin sections. The main facies association elements and relevant depositional settings have been interpreted by extracted Paleolog, facies and fossil association data which are related to depositional setting variations.

Highlights

The carbonate platform deposits of the Sarvak Formation were deposited in Late Albian to Early Turonian age [1] [2] [3] as the second most important carbonate reservoir in the Zagros Basin
Lithotype classification of the Sarvak Formation in the study field has been performed on the basis of the available geological subsurface data, paleolog interpretation
The relevant reservoir qualities are significantly controlled by facies properties, depositional environments and diagenetic impacts that normally increase or decrease the reservoir quality

Summary

Introduction

The carbonate platform deposits of the Sarvak Formation were deposited in Late Albian to Early Turonian age [1] [2] [3] as the second most important carbonate reservoir in the Zagros Basin. This formation is a thick carbonated unit that is deposited in Neotethys Southern Margin of Zagros Basin. The Sarvak Formation attains about 800 m thin, and medium to thick carbonate layers in thickness in its type section (Bangestan Mountain in vicinity of Izeh area). It conformably overlies the Kazhdumi Formation and unconformably covers by the argillaceous Gurpi Formation [3]

Methods

Results

Conclusion