No abstract

No abstract

No abstract

No abstract

Aiming at the problem of thin bed recognition in the thin interbed reservoir of the middle-shallow strata in the Songliao Basin, the broad frequency band and ultra high resolution seismic processing technique is studied. After the technique being applied in 3D seismic area of Zhaoyuan in the northern part of Songliao Basin, the seismic resolution increases 2–3 times compared with conventional seismic. It is known that characteristic of AVF is existed in seismic reflection through analyzing broad frequency band and high resolution seismic data and understanding characteristic of amplitude and frequency tuning effect of which originates from thin bed reservoir seismic reflection wave, two methods are given. One is that thickness of thin bed reservoir is calculated by AVF analysis, the other is that the distribution of thin bed reservoir is predicted by using proper broad frequency band and high resolution seismic. Through the fine contrast between seismic and wells data, the top and bottom interface of the F-2 pay zone are made sure. According to the results of seismic interpretation, the technique of seismic attributes extraction along stratum interface and 3D visualization technique are used to predict the horizontal distribution of reservoir on the F-2 pay zone. Taking the prediction result as basis, the applications on optimizing the location of the exploration wells, optimizing the zone of production test and analyzing the continuity of pay zone between the production wells are studied. They demonstrate the advantage of the high resolution seismic in the thin interbed reservoir prediction and the seismic recognition of lithologic reservoir. Introduction To date, oil exploration and development target of Songliao Basin is thin bed lithologic reservoirs which are medium to shallow buried layers with large areas, such as Putaohua and Fuyang reservoirs, they are high acoustic impedance thin sand bed of fluvial facies, individual layer thickness is between 2m to 7m, porosity is between 10% to 16%, permeability is between 1mD to 7mD, horizontal and vertical sand body varies dramatically. The thin bed reservoir predicting is the key technology on oil exploration and development, because of better condition on oil source of Putaohua and Fuyang reservoirs, better covering strata, also as long as better reservoir is found many areas. Predicting the distribution of thick bed reservoir by seismic is a mature technique, and many scholars have studied on predicting the distribution of thin bed reservoir by seismic before1–6. Nevertheless, predicting method of thin bed reservoir by conventional seismic meets a big challenge for resolution of conventional seismic is too low to satisfy the requirements of oil exploration and development on Songliao Basin. In this case, the broad frequency band and high resolution seismic technique7 is studied for solving this difficult problem. The technique takes many advantage, it can not only recover the attenuation of seismic wave around near source and near surface, but also can increase bandwidth from 5–90Hz to 5–360Hz. It is known that characteristic of AVF is existed in broad seismic data through analyzing broad frequency band and high resolution seismic data and understanding characteristic of tuning which originates from thin bed reservoir seismic reflection wave. Two methods of predicting thin bed reservoir are given. One is that thickness of thin bed reservoir is calculated by AVF analysis, the other is that the distribution of thin bed reservoir is predicted by using proper broad frequency band and high resolution seismic. These methods can increase the predicting accuracy and develop a large amount of oil reserves of thin bed reservoirs.