A Khodabakhshnezhad; M Pourkermani; M Arian; A.A Matkan; A Charchi
Abstract
Geomorphic indices of active tectonics are useful tools to analyze the influence of active tectonics in an area. These indices have the advantage of being calculated using ArcGIS and RS (Remote Sensing) packages over large areas as a reconnaissance tool to identify geomorphic anomalies possibly related ...
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Geomorphic indices of active tectonics are useful tools to analyze the influence of active tectonics in an area. These indices have the advantage of being calculated using ArcGIS and RS (Remote Sensing) packages over large areas as a reconnaissance tool to identify geomorphic anomalies possibly related to active tectonics. This is particularly valuable in Great Karoun River Basin of Zagros, where relatively little work on active tectonics based on this method was done. The study area in central Zagros fold- thrust-belt of the southwestern Iran is an area with NW–SE oriented structures provides an ideal location for testing the concept of an index to predict relative tectonic activity on a basis of river system or mountain front. Based upon values of the stream length-gradient index (SL), drainage basin asymmetry (Af), hypsometric integral (Hi), ratio of valley-floor width to valley height (Vf), index of drainage basin shape (Bs), and index of mountain front sinuosity (Smf), overall index as index of relative active tectonic (Iat) was resulted that is a combination of the other indices. This indices are used to divide the landscape into four classes of relative tectonic activity. After measuring indices it is concluded that this part of the Zagros zone has variable rates of active tectonics. Based on corrected Iat values, the study area was divided into three parts: class 1 (very high relative tectonic activity, %24 in area; such as some parts of the east and central zone where Main Zagros Reverse Fault and Dezful embayment fault have the most influence); class 2 (high relative tectonic activity, 63% in area; such as most parts of the area in east, west, north and center where action of faults are lower than the previous class); class 3(moderate, 10% in area; such as most parts of the area in north and south where action of faults are the lowest). Therefore, we don't have class 4 in this area, and 1% of basin is not measured for the indices because it is located in coastal plain of Khuzestan.
B Soleimani; G Saedi; A Charchi; E Salarvand
Abstract
Natural fractures analysis as a main controlling factor in fluid currents is very important in the reservoir characterization. This matter was studied using thin sections, cores, and FMI and velocity deviation logs in one of the fields in the southwestern of Iran. FMI initial data, which were input to ...
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Natural fractures analysis as a main controlling factor in fluid currents is very important in the reservoir characterization. This matter was studied using thin sections, cores, and FMI and velocity deviation logs in one of the fields in the southwestern of Iran. FMI initial data, which were input to Geoframe software, processed and interpreted. Velocity deviation logs and secondary porosity were also measured and compared. The results indicated that stylolites, pores, open and filled microfractures in the reservoir are present. The relative density of open fractures decreased to depth while filled fractures increased. The fractures are mainly longitudinal and latitudinal types with high angles to bedding surface. The main porosity system of the reservoir is inter particle and fractures types. According to the presence of oil staining in thin sections, it is revealed that the fractures are suitable conduits to transferring the fluid.
