TY - GEN
T1 - Diagenetic Alterations of the Outcropped Lower Triassic Mahil Formation (KS-1 Khuff-Equivalent) in the Oman Mountains, North Oman
AU - El-Ghali, Mohamed A.K.
AU - Moustafa, Mohamed S.H.
AU - Abbasi, Iftikhar Ahmed
AU - Al-Awah, Hezam
AU - Al Sarmi, Musaab Shakir
AU - Ali, Arshad
AU - Al-Sayigh, Abdulrazak
AU - Al Rab’ani, Rana
AU - Al Kindi, Basma
AU - Al Subhi, Najiya
AU - Rajendran, Sankaran
N1 - Publisher Copyright:
© 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
PY - 2023/12/19
Y1 - 2023/12/19
N2 - The Lower Triassic Mahil Formation in North Oman is the outcrop time-equivalents to the hydrocarbon-bearing reservoir, Upper Khuff Formation (referred to as KS-1 cycle). The studied sections of the KS-1 cycle in the Saiq Plateau and Wadi Sahtan of North Oman are ca. 50 m thick. They are dominated by dolomitized grainstones, less commonly dolomitized mudstones, and brecciated dolostone. The detailed petrographic analyses revealed various diagenetic alterations affecting pore types, pore throats, and pore size distributions. The identified diagenetic alterations include (i) near-surface to shallow burial (eodiagenesis), fine- to medium-crystalline dolomite, mostly with non-planer texture, through prevalent dolomitization of carbonates (allochems and matrix) via modified marine pore waters (δ18OVPDB = −4.2 to + 0.2‰), (ii) shallow burial (eodiagenesis), mechanical compaction as indicated by closely packed carbonate allochems grains, (iii) chemical compaction and stylolite development at the onset of deep burial (mesodiagenesis), (iv) precipitation of deep burial (mesodiagenesis), various types of coarse-crystalline dolomite cement, e.g., saddle texture cement (typically for deep burial) and rarely calcite cement via evolved marine pore waters, (v) fracture-filled calcite and dolomite cement with saddle texture, which is typical for deep burial (mesodiagenesis) and/or with equant drusy texture, which is typical for meteoric water diagenesis indicating its formation during telodiagenesis, and (vi) carbonate allochems grains and cement dissolution during progressive burial (eo- to mesodiagenesis) and/or during telodiagenesis. This study revealed that the Lower Triassic Mahil Formation in North Oman is deeply buried. Consequently, the porosity is destructed by extensive cementation and compaction through near-surface and progressive burial. However, on the other hand, porosity is enhanced by fracturing and dissolution of allochems grains during progressive burial and subsequent uplifting.
AB - The Lower Triassic Mahil Formation in North Oman is the outcrop time-equivalents to the hydrocarbon-bearing reservoir, Upper Khuff Formation (referred to as KS-1 cycle). The studied sections of the KS-1 cycle in the Saiq Plateau and Wadi Sahtan of North Oman are ca. 50 m thick. They are dominated by dolomitized grainstones, less commonly dolomitized mudstones, and brecciated dolostone. The detailed petrographic analyses revealed various diagenetic alterations affecting pore types, pore throats, and pore size distributions. The identified diagenetic alterations include (i) near-surface to shallow burial (eodiagenesis), fine- to medium-crystalline dolomite, mostly with non-planer texture, through prevalent dolomitization of carbonates (allochems and matrix) via modified marine pore waters (δ18OVPDB = −4.2 to + 0.2‰), (ii) shallow burial (eodiagenesis), mechanical compaction as indicated by closely packed carbonate allochems grains, (iii) chemical compaction and stylolite development at the onset of deep burial (mesodiagenesis), (iv) precipitation of deep burial (mesodiagenesis), various types of coarse-crystalline dolomite cement, e.g., saddle texture cement (typically for deep burial) and rarely calcite cement via evolved marine pore waters, (v) fracture-filled calcite and dolomite cement with saddle texture, which is typical for deep burial (mesodiagenesis) and/or with equant drusy texture, which is typical for meteoric water diagenesis indicating its formation during telodiagenesis, and (vi) carbonate allochems grains and cement dissolution during progressive burial (eo- to mesodiagenesis) and/or during telodiagenesis. This study revealed that the Lower Triassic Mahil Formation in North Oman is deeply buried. Consequently, the porosity is destructed by extensive cementation and compaction through near-surface and progressive burial. However, on the other hand, porosity is enhanced by fracturing and dissolution of allochems grains during progressive burial and subsequent uplifting.
KW - Carbonate diagenesis
KW - Lower Mahil formation
KW - Lower triassic
KW - Oman
UR - http://www.scopus.com/inward/record.url?scp=85180735507&partnerID=8YFLogxK
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U2 - 10.1007/978-3-031-43222-4_18
DO - 10.1007/978-3-031-43222-4_18
M3 - Conference contribution
AN - SCOPUS:85180735507
SN - 9783031432217
T3 - Advances in Science, Technology and Innovation
SP - 83
EP - 86
BT - Recent Research on Sedimentology, Stratigraphy, Paleontology, Tectonics, Geochemistry, Volcanology and Petroleum Geology - Proceedings of the 1st MedGU, Istanbul 2021 Volume 2
A2 - Çiner, Attila
A2 - Banerjee, Santanu
A2 - Lucci, Federico
A2 - Radwan, Ahmed E.
A2 - Shah, Afroz Ahmad
A2 - Doronzo, Domenico M.
A2 - Hamimi, Zakaria
A2 - Bauer, Wilfried
PB - Springer Nature
T2 - 1st International conference on Mediterranean Geosciences Union, MedGU 2021
Y2 - 25 November 2021 through 28 November 2021
ER -
