H Vafaei; M Peyravi
Abstract
The Kish gas-field is one of the world’s largest gas-fields, and consists of two reservoir rocks of Kangan (Lower Triassic) and Dalan (Late Permian) formations in the Zagros sedimentary basin. In this study, the Kangan formation has been examined. In this research, in addition to the use of raw ...
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The Kish gas-field is one of the world’s largest gas-fields, and consists of two reservoir rocks of Kangan (Lower Triassic) and Dalan (Late Permian) formations in the Zagros sedimentary basin. In this study, the Kangan formation has been examined. In this research, in addition to the use of raw data obtained from logging of a drilled well from the whole extent of the field, probabilistic petrophysics evaluation method was used to assess the petrophysical properties (shale volume, lithology, porosity and water saturation) of the Kangan formation. A method based on statistics and possibilities was also utilized to interpret the graphs (logs) with the help of multi-mineral model, a module of Multimin Software. Based on the results of this assessment and the use of lithology-determining cross-plots, as well as standard charts of Schlumberger, the dominant lithology of the Kangan formation in the studied well was recognized as calcite, dolomite, some anhydrite and small amounts of shale. The ultimate aim of the petrophysical evaluation in hydrocarbon studies of the Kish gas-field is to provide proper inputs to the reservoir static model. In order to make a more detailed study, this formation was divided into two parts, K1 and K2. As a whole, the calculated volume shale in the Kangan formation in this well is low and in K2 part is less. This could be considered as a reason for the equal effective porosity in most of the points along the well.
S. Nezamvafa; M. Rezaee; R. Moussavi-Harami; M. Bargrizan; A. Chehrazi
Abstract
Investigation and detail recognition of hydrocarbon reservoirs can have a good help in management of production wells, and field development. Burgan formation is deltaic sandstone from lower-median Cretaceous that is divided into three zones, A, B, and C. This formation ...
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Investigation and detail recognition of hydrocarbon reservoirs can have a good help in management of production wells, and field development. Burgan formation is deltaic sandstone from lower-median Cretaceous that is divided into three zones, A, B, and C. This formation in its type section (Kuwait) makes the second biggest world reservoir, with up to 72 billion barrels of in situ oil. In this study, evaluation of reservoir parameters has been made for this formation. Volume of shale, porosity, permeability, saturation, determination of oil water contact (OWC), net/gross and hydrocarbon column thickness, are the main reservoir parameters, that have been calculated with deterministic and problistic method using different logs and core data of 36 wells.
All of these parameters in problistic method have been calculated by professional petrophysic software, Geolog. Results of calculations show that despite of B zone lower thickness; this zone has a very high reservoir quality than the other two zones. This high quality arises from clean sand and high porosity (intergranualr) and permeability of this zone. Higher thickness of Burgan formation and its reservoir zones in the west of study field, and reservoir high quality in these horizons, show that the original source of clastic sediments is form the Arabian Shield toward Iran.