The Research And Application On Reservoir Objects Enhanced Methods

Along with the in-deep prospecting work for oil and gas, the prospecting targets turn intocomplex geological structures, lithologic hydrocarbon reservoir and complicated fault-blockhydrocarbon reservoir, such as minor-fault, micro sand body, narrow channel, etc. Besides,lithologic hydrocarbon reservoir has also became hot prospecting point. But the reflectancesignature of these geological structures and formations that mentioned above frequentlypresents weak reflection and waveform distortion. It is difficult to characterize the boundaryor to distinguish these bodies by conventional seismic techniques. It is necessary to utilizesome processing technologies to improve resolution and enhance the feature of weakreflection. By these processing thchnolies, the reservoir geological bodis get fine describedand enhancement display. Edge Detection algorithm, Blind Deconvolution algorithm andweak signal separation algorithm basing on Blind Source Separation can achieve the goalsthat mentioned above.The basic theory and applying scope of Edge Detection technology, Blind Deconvolutionand Blind Source Separation is different from each other. As Edge Detection algorithm, fordifferent operators that used in detection processing, the edge detection result is different. Inthis paper, we compare Facet model operator with common operators by processing geologicbody model. By analyzing the processing results, the advantage of Facet model operator isobviously. It is feasible to make use of this operator to process real seismic data. EdgeDetection processing is easily affected by noise. It is necessary to bring edge preservingsmoothing into the flow before detecting edges. Dip guided multi-window edge-preservingfiltering can preprocess data and get well filtering result while preserving edge feature. In realdata processing, we use Facet model gradient attribute detection operator for detecting andrealize fine describe and enhancement display of minor-fault that edge feature body. In theprocessing, we improve oriented-data extracting operator and optimize parametercombination. As Blind Deconvolution algorithm, Preconditioned Conjugate Gradient methodcould realize seismic data iterative processing under the condition of taking Cauchy criterionas constraint condition. Basing on this method and Cauchy constraint condition, BlindDeconvolution processing algorithm can get well processing result. The geophysical weak signal blind source separation model, which is constructed on BSS mixed model, providesbasic modeling and theory basis for weak signal extraction. In the processing procedure, thisalgorithm does iterative computations basing on Kalman optimal filtering thought andimproves the processing accuracy. By improving and optimizing the traces number thatinvolved in calculation and the length of predictive factor, the processing result gets better.The processing flow that basing on the analysis of each algorithm’s applicability, can choosethe optimal processing algorithm before data processing and get the best processing result andrealize the most optimize processing.Utilizing the three algorithms that discussed in this paper to process real seismic data, theprocessing results get well improved. Comparing with other operators, Facet model operatorthat along the stratigraphic shows many advantages as follows: Facet operator shows betterperformance when do noise suppression and preserves much edge feature while locating edgemuch more accurately. At the same time, some weak reflecting feature gets well characterizedand displays. Blind Deconvolution algorithm that basing on PCG and weak signal separationalgorithm basing on BSS improves resolution effectively while maintains the continuity ofevents. Some formations that difficult to identified in original section get more easily identifyand display much more clearly and intuitively. The processing result enhances theidentification ability of weak reflection feature. The enhancement processing flow of weakreflection feature have practical value and guided meaning about reservoir objects weakinformation enhancement.