The Study On The Fine Description Of Reservoir And The Predicting Of Advantageous Exploration Target In Weibei Depression

Weibei depression with abundant hydrocarbon resources is one of the key areas of hydrocarbon exploration of peripheral regions in Shengli oil field. Weibei depression has great potential of hydrocarbon exploration. However, the hydrocarbon exploration, especial in deep formation of Weibei depression has not gained notable breakthrough because Weibei depression with complicated geological structure is a relative small basin, and because the sedimentary systems are of interlaced congruence in vertical and horizontal direction due to the multidirectional sources of sediment in the depression. As a result, there are still three contradictions between demonstrated reserves and reserves of potential resource, between degrees of exploration between zones and between the effects and potentiality of exploration of deep gas in north sag of Weibei depression. Therefore, basically, the breakthrough on the hydrocarbon exploration of Weibei depression depends on the recognition of the upgrowth and distribution of reservoir in Weibei depression.In this paper, aiming at the problems in hydrocarbon exploration and the features of complicated sedimentation and structure of Weibei depression, a comprehensive research on the upgrowth and distribution of reservoir in Weibei depression has been finished with multidisciplinary technology and methods, such as geology, seism, well logging and integrated judgment methods. The key research is the formational sequence and the sedimentary characteristic of Weibei depression. The contrast framework of formation has been built up by the study on the formational sequence of Weibei depression. The forecast model of reservoir has been established according to the result of integrated evaluation of reservoir of Weibei depression. In this paper, finally, combined all the research results in the paper with other information of hydrocarbon occurrence, trap types and the migration and gathering of hydrocarbon in Weibei depression, forecast and evaluate the advantageous bed sets and zones of containing oil and gas, and then point out serial advantaged exploration targets.In this paper, a series of study methods and description technology of reservoir suitable for this kind of basin with complicated geological structure and great change of sedimentation have been established with multidisciplinary technology and methods based upon the combination of geology, well drilling and logging data. This paper has sought for some new ways to study and forecasting on the distribution of reservoir for this kind ofarea.In the thesis, there are some novel discusses and researches. Using the method of sequence stratigraphy for the first time, stratigraphic subdivision and correlation of Weibei depression have been finished by sequence, system tract and subsequence. As a result, the stratum of Kongdian formation has been divided into one second-class sequence, five third-class sequences. Therefore, the formation framework of Weibei depression has been built up.Using the method of ancient geography sequence for the first time, the subdivision of sedimentary facies, intrafacies and microfacies has been done, and the distribution of sedimentary facies in different sequences has also been studied. Consequently, a new mode of sedimentation of Weibei depression has been established.By the deep research on the diagenesis and diagenetic stage of Weibei depression, in the paper, the concept of diagenetic facies has been put forward, and the investigate method of diagenetic facies has also been set up accordingly. A series of diagrams, such as the figure of diagenetic factor, the figure of pseudo specific compaction and the figure of pseudo percent consolidation of the reservoir in Weibei depression, have been compiled for the first time. These diagrams can reflect the changes of diagenesis in formational sequence of Weibei depression. Therefore, these researches have provided the important basis for the evaluation of reservoir in Weibei depression.