Seismic Interpretation And Reservoir Prediction Of Volcanic Rocks From Yingcheng Formation In Linjiang Area

In this thesis, based on the sequence stratigraphy, the structural geology and the seismicreservoir prediction theory, the division of the volcanic seismic cycle and reservoir predictionhave already completed, according to the comprehensive analysis and application of theseismic and log data of Yingcheng formation in Linjiang area, as well as the division of thefavorable area.In this study, according to the yclicity and intermittent characteristics of the volcaniceruption, the Yingcheng formation in Linjiang area is divided into three cycles and six timesof stage.combined with the seismic and well log characteristics. And based on the7seismicreflection horizons interpretationg of T4-1, T4a, Tyc1ax, Tyc1a, Tyc1bx, Tyc1b, Tyc1cx and thestructural maps, the structural characteristics of the Yingcheng formation in Linjiang area hasbeen studied preliminarily. According to the characteristics of the ring, radial structure of thevolcanic crater, volcanic agencies of each times of state have been identified combined withthe coherence technology and the trend surface analysis technology, which was used toresearch the laws of the volcano eruption. And on this basis, volcanic facies were divided foreach time of stage, with the waveform clustering of seismic facies analysis and multi-attributemulti-display means, which was used to identify the boundary of the volcanic facies. Thevolcanic facies in plane contain Volcano crater facies group, proximal facies group, distalfacies groups and volcanic sedimentary facies groups.Based on the single well lithology and reservoir data of the well Yingshen2andYingshen4of this area and well Yingshen1of the adjacent area, the volcanic of this area canbe divided into andesite, dacite, rhyolite and sedimentary rocks, which was easy to analyzethe petrophysical characteristics of the study area. On the basis of CRP gathers pretreatment,pre-stack AVO inversion synchronization was used to predict the volcanic rocks andreservoirs combined with the sensitive parameters analysis. And the curvature properties andAVO attributes were used to forecast the volcanic fissures and hydrocarbon developmentareas respectively. On this basis, the favorable area for each cycle of the Yingcheng formationin Linjiang area can be divided finaly.The studies have shown that: the volcanic facies control the distribution of reservoirwithin the volcanic edifice, where the crater facies group is the most favorable facies; thewidely development of the fault and unconformity promote the formation of cracks, whichimprove the volcanic reservoir connectivity. Therefore, in this study area the favorablereservoir development area are affected by the integrity degree of the volcano edifice, thedevelopment degree of fault and the distance from the surface of the unconformity.