TY - JOUR

T1 - Depositional facies and diagenetic control on reservoir quality of the Aptian Dariyan Formation, NW Persian Gulf

AU - Jafarian, Arman

AU - Kakemem, Umid

AU - Husinec, Antun

AU - Mehrabi, Hamzeh

AU - Javanbakht, Mohammad

AU - Wang, Chengshan

AU - Chen, Xi

AU - Li, Yalin

N1 - Publisher Copyright: © 2024 Elsevier Ltd

PY - 2024

Y1 - 2024

N2 - The Aptian Dariyan (Shu'aiba) Formation is one of the major Cretaceous reservoirs in the Middle East. Despite its economic significance, an understanding of the influence of depositional facies and a sequence of diagenetic events on its reservoir quality remains limited. Here, we address this challenge through analysis (facies, petrophysics, geochemistry) of a continuous, ∼180 m thick core from NW Persian Gulf, and a fully-automated identification of hydraulic flow units (HFUs). Ten carbonate and four predominantly siliciclastic facies were identified as part of four facies associations, from shallowest to deepest: mixed tidal flats, inner ramp (lagoon and shoals), shallow open-marine mid ramp, and deep open-marine (outer ramp and intrashelf basin). The stacking pattern of facies yields five third-order transgressive-regressive sequences. Three hydraulic flow units (HFUs) were identified and evaluated against lithology and petrophysical values: baffle unit (HFU1), normal unit (HFU2), and permeable unit (HFU3). The permeable unit exhibits good storage capacity and moderate flow capacity. The data reveal an overall complex paragenetic and porosity-modification history of the Dariyan Formation. The overwhelmingly mud-dominated texture of the facies, along with meteoric-zone dissolution under a predominantly warm and humid greenhouse climate during periods of relatively low sea level, and subsequent fracturing during deep burial played a major role in controlling the reservoir quality.

AB - The Aptian Dariyan (Shu'aiba) Formation is one of the major Cretaceous reservoirs in the Middle East. Despite its economic significance, an understanding of the influence of depositional facies and a sequence of diagenetic events on its reservoir quality remains limited. Here, we address this challenge through analysis (facies, petrophysics, geochemistry) of a continuous, ∼180 m thick core from NW Persian Gulf, and a fully-automated identification of hydraulic flow units (HFUs). Ten carbonate and four predominantly siliciclastic facies were identified as part of four facies associations, from shallowest to deepest: mixed tidal flats, inner ramp (lagoon and shoals), shallow open-marine mid ramp, and deep open-marine (outer ramp and intrashelf basin). The stacking pattern of facies yields five third-order transgressive-regressive sequences. Three hydraulic flow units (HFUs) were identified and evaluated against lithology and petrophysical values: baffle unit (HFU1), normal unit (HFU2), and permeable unit (HFU3). The permeable unit exhibits good storage capacity and moderate flow capacity. The data reveal an overall complex paragenetic and porosity-modification history of the Dariyan Formation. The overwhelmingly mud-dominated texture of the facies, along with meteoric-zone dissolution under a predominantly warm and humid greenhouse climate during periods of relatively low sea level, and subsequent fracturing during deep burial played a major role in controlling the reservoir quality.

KW - Dariyan (Shu'aiba equivalent) formation

KW - Diagenesis and geochemistry

KW - Intrashelf basin

KW - Persian gulf superbasin

KW - Reservoir quality

U2 - 10.1016/j.marpetgeo.2024.106895

DO - 10.1016/j.marpetgeo.2024.106895

M3 - Journal article

AN - SCOPUS:85192569273

VL - 165

JO - Marine and Petroleum Geology

JF - Marine and Petroleum Geology

SN - 0264-8172

M1 - 106895

ER -