Application of wave impedance inversion technology based on wavelet edge analysis and combined well-seismic modeling in reservoir prediction of Luliang uplift zone

The Luliang uplift zone in the Junggar Basin exhibits intricate fault structures,laterally heterogeneous reservoirs,and small-scale and thin gas-bearing sand bodies,presenting challenges in reservoir prediction.Hence,this study applied the wave impedance inversion technology based on wavelet edge analysis and well-seismic joint modeling to directly extract seismic attributes' characteristic parameters that reflect structural and lithological changes from seismic records.These seismic attribute characteristic parameters were used to build the initial model together with acoustic impedance logs and participated in disturbance modification of the wave impedance model.This inversion technology counteracted the lack of inter-well high-frequency components and the inter-well local lithologic changes during the inter-well interpolation modeling and avoided error information caused by the inaccurate initial model in the conventional wave impedance inversion,thus improving the resolution of seismic data in identifying small-scale and thin sand bodies.The results show that under the control of the provenance of the Kelameili Mountain in the east,a fan delta-semideep (deep) lacustrine sedimentary system formed in the Wutonggou Formation in the DX14 well area of the Luliang uplift zone,hosting many fan delta-front sand bodies.The comparison between the actual drilling results and the pre-drilling prediction results indicates that the absolute error and relative mean error of sandstone thickness prediction at the well site were less than 0.60 m and less than 2.84%,respectively,suggesting that the prediction accuracy meets the requirements of fine-scale reservoir prediction.The research results provide a guide for fine-scale reservoir description and well deployment.