Study Of Seismic Parameters Comprehensive Prediction Technology And Application About Gas Reservoirs In Thin Carbonate Rock

Seismic information is compositive reflection of all kinds of characteristic in reservoir bed, which includes lithologic character, physical property, fluid, fracture etc. On the other hand, seismic information integrates tens of seismic parameters anyone of which reflected character of reservoir bed or gas reservoir in different side and different degree. Prediction with one parameter has limitation and multi-interpretation and bring risk to petroleum exploration. Especially, prediction with single parameter or seismic velocity reversion is poor in thin carbonate bed.To the same tectonic unit, lithologic character and physical property of reservoir bed are stable relatively, which can be thought of as constant of system, while fluid, fracture etc are variable to seismic information function. All kinds of seismic parameter must have relations to gas reservoir , parameters comprehensive prediction just about analyze these relativity. Before, we do it by manual work, that's to say, new characteristic vector is composed of K kind characteristic parameters selected from M kind characteristic parameters. This method needs hold exhaustive geologic, logging datum, know applicability of and delete those parameters not adapt to the area, while this method will bring on mass workload , rough result and strong jamming. In a general way, M kind characteristic parameters all come from certain character which reflected object and deleting simply can not depict original object.Seismic compositive parameter can be devided into multiple single parameters by mathematics and computer means. By deposing these parameters, such as normalization, reducing dimensions, generalized linear classify differentiating and statistical weight comprehensive disposal etc, a comprehensive parameter can be acquired reflecting character of reservoir bed and prediction precision of seismic parameter method can be improved. This method also get good effect.Seismic parameter comprehensive prediction method is composed of inputing seismic data, extracting seismic data of reservoir bed, analyzing parameter and predicting gas reservoir synthetically etc. This prediction system can finish disassociation, analyzing, compressing, integrating of information by computer. This will reduce subjectivity of man, stand out parameters relative to gas/oil, predict best part of reservoir bed rich of oil/gas and local area rich of oil/gas.Seismic parameter comprehensive prediction method used in this paper is not filtering parameters and analyzing artificially simply, but integrating a new parameter reflecting character of gas reservoir, by combining with drillhole exploration fact, adopting routinization and scientific method. This method develops new method and technology about thin reservoir bed in carbonate rock, acquired better new progression and important outcome in prediton of reservoir bed.