Method for quantificationally predicting sandstone reservoir fluid saturation by combining well and seism

Abstract

The invention discloses a method for quantificationally predicting sandstone reservoir fluid saturation by combining a well and seism in geophysical prospecting for petroleum. The method comprises the following steps of: acquiring and processing seismic data and log data to obtain each parameter curve; respectively determining the relationships among the shale content, the porosity and an elastic parameter of the well; establishing prediction models of the shale content and the porosity; calculating a pore volume modulus and a dry rock volume modulus to establish a modulus prediction model; establishing an effective reservoir water saturation prediction model; performing prestack seismic inversion by utilizing prestack seismic trace gathers and the log data to obtain an inversion data volume of each elastic parameter; calculating the dry rock volume modulus to solve the pore volume modulus by the obtained elastic inversion volume; and solving the water saturation by using the pore volume modulus. In the method, prestack seismic data and the log data are fully utilized for quantificationally predicting reservoir saturation; and good geological effects on predicting oil and gas saturation are achieved.

Description

technical field [0001] The invention relates to petroleum geophysical exploration technology, in particular to a method for quantitatively predicting fluid saturation of sandstone reservoirs based on pore bulk modulus combined with well and seismic. Background technique [0002] Using seismic data to predict the pore fluid of subsurface rocks is the goal of seismic work. As one of the means of direct detection of oil and gas, AVO (amplitude with offset) attribute analysis has played an important role in the detection of bright spots and flat point gas reservoirs. Qualitative description, and there are many pitfalls. Seismic inversion, especially the emergence of pre-stack seismic inversion technology, makes it possible to quantitatively predict reservoir pore fluids using seismic data. In recent years, the use of seismic data for oil and gas prediction has become a hot spot, but the main research results still focus on the qualitative description and prediction of fluids, ...

AI Technical Summary

Problems solved by technology

Jin Long et al. proposed a new method for simultaneously inverting porosity and saturation based on a rock physics model and a hybrid optimization algorithm (Acta Petroleum Sinica, 2006, Vol. 27, No. 4). This method adds porosity and saturation to the inversion process As a constraint, its stability and validity have been tested by the model calculation results, but it has not been applied to the actual seismic data

It can be seen that there is no practical and effective method for quantitatively predicting saturation at home and abroad.

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