Kharazmi Journal of Earth Sciences

Kharazmi Journal of Earth Sciences

Investigation and analysis of reservoir zonation in the Fahliyan Formation using pressure, petrophysical, and core data from an oil field in southwestern Iran

Authors
Hadis Arvani
Mahdi Amirsardari
Jahanbakhsh Daneshian
Kharazmi University
10.22034/KJES.2025.11.1.107851
Abstract
The Fahliyan Formation, as one of the most important hydrocarbon reservoirs in southwestern Iran, exhibits significant geological and reservoir complexities. This study integrates petrophysical data, pressure data, and core analysis to perform comprehensive reservoir characterization and zonation. Through integrated analytical methods, reservoir layers with similar petrophysical properties and flow behavior were identified and classified. The research utilized wireline log data (gamma ray, neutron, density, and resistivity logs) from an oil field in the Abadan Plain region, employing probabilistic petrophysical evaluation in Geolog software to assess the Fahliyan Formation's reservoir quality and determine key parameters including porosity, water saturation, and lithology. Core laboratory data from porosity analysis and petrographic studies were used for validation. Reservoir pressure data served as a critical tool for precise zonation control and identification of independent hydraulic units. Results reveal the Fahliyan Formation's high degree of heterogeneity, with the reservoir divided into 10 zones in Well A and 12 zones in Well B. The most productive zones were identified as F3, F5, F7, F9, and F10 in Well A and F5, F7, F9, and F11 in Well B, which contribute significantly to oil production. However, impermeable and compacted zones (F6, F8, and F10 in Well B) create hydraulic barriers between adjacent zones, as confirmed by petrophysical log responses. This study demonstrates that the integrated approach combining petrophysical analysis, core data, and pressure measurements provides an effective methodology for accurate reservoir zonation and identification of productive intervals in this complex carbonate formation, offering valuable insights for field development planning and optimal hydrocarbon recovery from the heterogeneous Fahliyan reservoir.
Keywords
Petrophysical evaluation
pressure data
reservoir zonation
Fahliyan Formation
reservoir heterogeneity
Subjects
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Kharazmi Journal of Earth Sciences
Volume 11, Issue 1 - Serial Number 21
September 2025
Pages 47-71