A Computer Aided Sequence Stratigraphy Approach For Reservoir Characterization Using Neutral Network and Fuzzy Logic of Sanghar Area, Southern Indus Basin, Pakistan
Earth and envirimental Sciences, Bahria University, Islamabad, Pakistan.
Research work was carriedout at Sanghar district situated at Thar platform, Southern Indus Basin. The well ICHHRI-01 is located at 63km North of Bobi filed in Khairpur District, Sindh Province. The well was drilled by OGDCL to test hydrocarbon potential of sands of Lower Goru formation of cretaceous age.
Research revolves around Reservoir characterization in which two approaches of predictive reservoir and realistic reservoir characterization introduced. The approaches helpful to get maximum use of the seismic data with less control of wells. The methodology adopt to test and use original workflow for seismic structural and sequence stratigraphic interpretation system(SSIS). Seismic lines used to quickly build digital chronostratigraphic framework for the Lower Cretaceous. The sequence stratigraphic meaning to depositional sequences are assigned. After that Wheeler diagrams generated which is used in different depositional histories (depositional sequence geometries and stacking patterns within a common stratigraphic framework). Realistic reservoir methods including attribute analysis,spectral decomposition,neural networks and fuzzy logic is worn to minimize uncertainty which help interpreter to take full use of seismic and geologic dataset.Neural network is non-linear statistical data modeling tool which is able to model complex relationships between inputs and outputs or to find patterns in data. Similarly,Fuzzy logic has termed as self-filtering technique using logical expression.This method act as self-filtering technique in interpretation because this method filter out result and combine the number of results by using logical expression.It also dependent upon the knowledge of interpreter and the way to apply the logic for specific subsurface interpretation.I termed it as self-filtering technique in interpretation.
The paper illustrate how predictive seismic stratigraphic characterization results with realistic seismic characterization and improved interpret seismic sections along with available well information which further used in modeling. Two methods not only help minimize the uncertainty but at same time requires interpreter to take full use of seismic and geologic dataset. By comparing seismic sections (stratigraphically and structurally) and well logs with realistic reservoir approach it appeared that all expected reservoir sand layers of Lower Cretaceous are present but expected reservoir play is towards the western side of the study area.
AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012