Abstract
With the modern geological and geophysical study maturity, the problem of the exploration and in-field exploration stages is based not only on the building of proper structural model of the field, but also on the prediction of reservoir properties by various methods of quantitative interpretation. This paper describes application of seismic inversion with the purpose of receiving reliable results about reservoir layers characterization and analysis of lithology. Loss or reduction in the quality of well and seismic data during the registration of curve, fieldwork and/or during processing, absence or bad quality of well logs lead to restriction of the usage of different seismic inversion algorithms. As a result, it is not always possible to obtain reliable quantitative prediction of reservoir properties.
Seismic inversion was realized on two oil and gas fields. For the inversion, different packages of well and seismic data are used. Well logging response from acoustic and density due to various technological and geologic-geophysical reasons is subject to noticeable distortion. In this regard, for more reliable results normalizing, correction and synthesis of curves have been carried out by different methods.
On the first field the executed complex of well logs has allowed to divide sedimentary section on reservoir and surrounding formations, however it was not possible to receive appropriate petrophysical model. Low coefficient ratio of seismic well tie (0, 52) did not allow to execute qualitative inversion.
On the second field as a result of simultaneous inversion with the use of logging data after correction the most positive prediction of reservoir properties is received. Corrected data are uniform and contains the smallest number of artifacts that provide the correct distribution of trend values of the decision.
The result of seismic inversion depends on the quality of input data. Therefore, as long as the proper attention is not paid to the quality of the recording instruments and seismic surveys, to the number and completeness of the necessary methods, especially important is to carry out data quality control for quantitative interpretation. Without use of reliable results of inversion transformations, it is impossible to predict reasonably and accurately reservoir properties of perspective objects and estimate their resources.
