Fine Structure Interpreting Technique And Its Application By Integrating Well-to-seismic Information In Sanan Development Area

Saertu structure, a tertiary structure of placanticline, coincides in its southernportions with the Sanan development block. Sanan structure is a transapical axisanticline with its axis pointing30-50degrees northeastward, an backlimb in the eastdipping only3-5degrees and a20degrees dipping wing in the west. Its fracturesystem which is composed of103normal faults is very complicated. The layer seriesof development are Saertu formation, Putaohua formation and Gaotaizi formationaccumulated mainly as river-delta sedimentation which was buried shallow andcomposed of thin and laterally fast changing sand shale sequence. During the50yearsexploration and development in the Sanan development block, basic well pattern,primary well pattern, secondary well pattern, third well pattern and polymer floodingwell pattern were built and although the pattern size is rather small and the number ofbreaking points is large, for quite a long time the recognition of faults was largelybased on well log resulting in faults with too much subjectivity especially secondaryfaults. In order to recover the remaining removable oil, increase the produciblereserves, and improve the oil field development effect, it is necessary to carry out theresearch of high resolution structure recognition apparently.With the opportunity of high resolution3dimensional seismic structure andreservoir interpretation campaign, the author tries to build an interpretation flow chartsuitable for small size well pattern in the aspects of synthetic seismogram making,horizon interpretation and the recognition of secondary faults based on the processedhigh resolution seismic data acquired in2008, research in the fields of well drilling,well logging and so on, and the theory of3dimensional seismic interpretation. At thesame time, the author makes it into reality creatively to transfer depth domain to timedomain fast based on the software of Petrel.Firstly, the author tries to figure out the possibility of recognizing different scalesof faults in different noise background in the guidance of theoretical forwardmodeling. Secondly, the realization of the method of instant depth domain to timedomain conversion based on Petrel contributes a lot in efficiency promotion ratherthan making a lot of synthetic seismograms. According to the consecutivity of keyhorizons in seismic, the author applies different method to reduce the losing ofgeological information resulting from human intervention. The author carries themethod of formation constraining interpolation interpretation into reality, whichmakes it possible to track horizons with less consecutivity. In the aspect of faultinterpretation, the author use different methods according to the scales of the faults; for faults with displacement more than10meters, the author interprets them in theguidance of coherence cube horizon slice in the windows of2dimensions and3dimensions synchronously; for faults with displacement less than10meters, theauthor interprets them in the guidance of breaking points from well logging and withthe assistance of coherence cube horizon slice, curvature cube horizon slice, ant cubehorizon slice, and variance cube horizon slice.The research of high resolution structure interpretation reconstructs the fracturesystem, which lights fault control remaining oil, provides guidance for developmentplan adjustment, adjustment wells addition, high efficiency wells addition, slant wellsaddition, completes the flooding and producing system adjustment, and providesinformation for hole pattern in the transition zone; all these methods provideguarantee in the process of sustainable development of the oil fields.