Inversion of initial model construction by geological statistics and its influence on inversion results under dense well pattern

The simplified initial model without adding fault information often makes the prediction accuracy of seismic inversion result worse near faults and then the distribution of sand bodies cannot be described accurately.A case study of the development zone with dense well pattern in Daqing Changyuan oilfield,a high precision layer model and structure model was constructed by integrating well log and seismic information,and an initial model of inversion with accurate structure information were constructed.Under the initial model,the geological statistics inversion was carried out,the accuracy of seismic inversion under different starting models was compared.The results show that the initial model with adding fault information can effectively improve the prediction accuracy of sandstone prediction,which is based on the results of the geological statistics inversion.The pre-diction accuracy of sandstone with thickness greater than 3m can be increased by about 7%.The prediction accuracy of sandstone with the thickness range from1 m to 3m can be increased by about 11%.The prediction accuracy of sandstone with the thickness less than 1m can be increased by about12%.