The Early Triassic Kangan Formation is the main reservoir for natural gas in SW Iran and the nort... more The Early Triassic Kangan Formation is the main reservoir for natural gas in SW Iran and the northern Persian Gulf and is equivalent to the Upper Khuff Formation. Analyses of the formation at the offshore Salman and Minab oilfields indicate that it is composed of 14 facies deposited in tidal flat, lagoon and oolitic barrier settings in the inner part of a carbonate ramp or platform. Vertical variations of microfacies and gamma‐ray log profiles show that the formation consists of three depositional sequences (KG1–3), each consisting of transgressive and highstand systems tracts and each bounded above by a type 2 unconformity. Porosity in the Kangan Formation is dominated by fracture and intercrystalline pore types in highstand systems tract deposits.From a study of core plug porosity and permeability, ten flow units were recognized. Flow units GF1, GF5 and GF8 represent zones with similar flow and storage capacities. Flow units GF3, GF7 and GF9 were attributed to zones of higher flow capacity, and units GF2, GF4, GF6 and GF10 were interpreted as zones with higher storage capacities. In general, flow units which correspond to highstand systems tracts with grain‐supported facies have enhanced reservoir qualities. These flow units are GF10, GF9, GF8 and GF7, together with the upper parts of GF5 and GF4. The best reservoir quality occurs in flow unit GF9 which is located in the HST of sequence KG3. Flow units GF1 and GF2 from sequence KG1, comprising lagoonal and tidal flat facies, have relatively poor reservoir qualities.
Porosity generation and reservoir potential of the early Cambrian Ouldburra Formation in the east... more Porosity generation and reservoir potential of the early Cambrian Ouldburra Formation in the eastern Officer Basin is delineated by combining petrographical, petrophysical and sedimentological studies. The shallow marine Ouldburra Formation consists of carbonates, mixed carbonates and clastics, clastics and evaporites. Detailed analysis of more than 100 samples shows that dolomitisation resulted in substantial secondary porosity development within the carbonates. Secondary porosity has also been generated within the mixed siliciclastic-carbonate zone by carbonate matrix and grain dissolution as well as by dolomitisation. Prospective reservoir units correspond to highstand shallow marine facies where short periods of subaerial exposure resulted in diagenetic changes.Sedimentary facies and rock character indicate that sabkha and brine reflux models are applied to dolomitisation within the Ouldburra Formation. Dolomite mainly occurs in two stages: common anhedral dolomites formed early by replacement of pre-existing limestone, and saddle dolomite and coarse crystalline dolomite formed during the late stages of burial diagenesis, associated with hydrocarbon shows. The dolomite reservoirs identified are ranked on the basis of their porosity distribution and texture into groups I to IV. Dolomites with rank I and II exhibit excellent to good reservoir characteristics respectively.The Ouldburra Formation shows many depositional and diagenetic similarities to the Richfield Member of the Lucas Formation in the Michigan Basin of the USA. Substantial oil and gas production from middle Devonian shallow water to sabkha dolomites makes the Richfield Member an attractive reservoir analogue to the Ouldburra Formation.
The early to middle Cenomanian argillaceous limestone and shale sequence in the Iranian sector of... more The early to middle Cenomanian argillaceous limestone and shale sequence in the Iranian sector of Persian Gulf (ISPG) is the main source rock for the Cretaceous petroleum system in the area. But the source rock has no good distributed observed data to evaluate it in the basin. In order to remove this limitation, construction a basin-wide dynamic model subjected for investigating. Burial history and maturity level of the source rock were calculated and mapped over the entire basin during the geologic times by the model. The final results of the integrated model indicated that the sequence is a good oil prone source rock in some parts of the area which is characterized by good total organic carbon, fine organic matter type, noticeable thickness, and high maturity. The main hydrocarbon kitchen identified in the area has been located in the southeast of the ISPG. This source rock began to generate oil from 65 to 45 Ma and gas during 45-6 Ma in the area and the times of peak oil generation are recorded in the range 55-50 Ma at the depths below 2800 m in the main depocentres. Present day maturity status of the source rock is in wet gas condition.
Journal of Stratigraphy and Sedimentology Researches, 2015
The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil fiel... more The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil field using Rock- Eval VI pryrolysis. Geochemical analysis indicated that Pabdeh Formation possesses poor to good hydrocarbon potential. Plotting S1 against TOC suggests that samples were not affected by polluting substances such as crude oil and lubricants while drilling operation. Jones organic fancies diagram shows B-BC area indicating that Pabdeh Formation was deposited in marine anoxic to oxic environments. HI vesus Tmax shows that most samples initially have had type II kerogen and now reflecting a mixture of type II to III kerogen (capable of generating oil) that have already entered oil generation window. In addition, S1+S2 versus TOC plot also suggests that Pabdeh Formation can be considered as a capable hydrocarbon generating source rock in the study area.
The Early Triassic Kangan Formation is the main reservoir for natural gas in SW Iran and the nort... more The Early Triassic Kangan Formation is the main reservoir for natural gas in SW Iran and the northern Persian Gulf and is equivalent to the Upper Khuff Formation. Analyses of the formation at the offshore Salman and Minab oilfields indicate that it is composed of 14 facies deposited in tidal flat, lagoon and oolitic barrier settings in the inner part of a carbonate ramp or platform. Vertical variations of microfacies and gamma‐ray log profiles show that the formation consists of three depositional sequences (KG1–3), each consisting of transgressive and highstand systems tracts and each bounded above by a type 2 unconformity. Porosity in the Kangan Formation is dominated by fracture and intercrystalline pore types in highstand systems tract deposits.From a study of core plug porosity and permeability, ten flow units were recognized. Flow units GF1, GF5 and GF8 represent zones with similar flow and storage capacities. Flow units GF3, GF7 and GF9 were attributed to zones of higher flow capacity, and units GF2, GF4, GF6 and GF10 were interpreted as zones with higher storage capacities. In general, flow units which correspond to highstand systems tracts with grain‐supported facies have enhanced reservoir qualities. These flow units are GF10, GF9, GF8 and GF7, together with the upper parts of GF5 and GF4. The best reservoir quality occurs in flow unit GF9 which is located in the HST of sequence KG3. Flow units GF1 and GF2 from sequence KG1, comprising lagoonal and tidal flat facies, have relatively poor reservoir qualities.
Porosity generation and reservoir potential of the early Cambrian Ouldburra Formation in the east... more Porosity generation and reservoir potential of the early Cambrian Ouldburra Formation in the eastern Officer Basin is delineated by combining petrographical, petrophysical and sedimentological studies. The shallow marine Ouldburra Formation consists of carbonates, mixed carbonates and clastics, clastics and evaporites. Detailed analysis of more than 100 samples shows that dolomitisation resulted in substantial secondary porosity development within the carbonates. Secondary porosity has also been generated within the mixed siliciclastic-carbonate zone by carbonate matrix and grain dissolution as well as by dolomitisation. Prospective reservoir units correspond to highstand shallow marine facies where short periods of subaerial exposure resulted in diagenetic changes.Sedimentary facies and rock character indicate that sabkha and brine reflux models are applied to dolomitisation within the Ouldburra Formation. Dolomite mainly occurs in two stages: common anhedral dolomites formed early by replacement of pre-existing limestone, and saddle dolomite and coarse crystalline dolomite formed during the late stages of burial diagenesis, associated with hydrocarbon shows. The dolomite reservoirs identified are ranked on the basis of their porosity distribution and texture into groups I to IV. Dolomites with rank I and II exhibit excellent to good reservoir characteristics respectively.The Ouldburra Formation shows many depositional and diagenetic similarities to the Richfield Member of the Lucas Formation in the Michigan Basin of the USA. Substantial oil and gas production from middle Devonian shallow water to sabkha dolomites makes the Richfield Member an attractive reservoir analogue to the Ouldburra Formation.
The early to middle Cenomanian argillaceous limestone and shale sequence in the Iranian sector of... more The early to middle Cenomanian argillaceous limestone and shale sequence in the Iranian sector of Persian Gulf (ISPG) is the main source rock for the Cretaceous petroleum system in the area. But the source rock has no good distributed observed data to evaluate it in the basin. In order to remove this limitation, construction a basin-wide dynamic model subjected for investigating. Burial history and maturity level of the source rock were calculated and mapped over the entire basin during the geologic times by the model. The final results of the integrated model indicated that the sequence is a good oil prone source rock in some parts of the area which is characterized by good total organic carbon, fine organic matter type, noticeable thickness, and high maturity. The main hydrocarbon kitchen identified in the area has been located in the southeast of the ISPG. This source rock began to generate oil from 65 to 45 Ma and gas during 45-6 Ma in the area and the times of peak oil generation are recorded in the range 55-50 Ma at the depths below 2800 m in the main depocentres. Present day maturity status of the source rock is in wet gas condition.
Journal of Stratigraphy and Sedimentology Researches, 2015
The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil fiel... more The present study was performed on 59 drillhole cuttings from Pabdeh Formation in Nosrat oil field using Rock- Eval VI pryrolysis. Geochemical analysis indicated that Pabdeh Formation possesses poor to good hydrocarbon potential. Plotting S1 against TOC suggests that samples were not affected by polluting substances such as crude oil and lubricants while drilling operation. Jones organic fancies diagram shows B-BC area indicating that Pabdeh Formation was deposited in marine anoxic to oxic environments. HI vesus Tmax shows that most samples initially have had type II kerogen and now reflecting a mixture of type II to III kerogen (capable of generating oil) that have already entered oil generation window. In addition, S1+S2 versus TOC plot also suggests that Pabdeh Formation can be considered as a capable hydrocarbon generating source rock in the study area.
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Papers by Mohammad Reza Kamali