3D Seismic Fine Interpretation Technique And Its Application In Southern Area Of WUERXUN Depression In HAILAER Basin

Southern area of WUERXUN Depression in HAILAER Basin was suffered by multiphase tectonic activity, multiphase basin superimposition, with faulted structure complexity, block fault development, so it has depositional characteristic of multi-deposition, lack deposition and quick phase change, which causes great changes in the horizontal orientation of seismic reflection characteristic, and brings great difficulties for seismic data interpretation, if we still adopt former vacuating method of 3D seismic data with 2D interpretation measure, the effect of seismic interpretation will certainly be affected.In view of complex structural and sedimentation feature of Nantun Formation in southern area of WUERXUN Depression in HAILAER Basin, and based on vertical thin sand Formation and fine well-to-seismic calibration, the article adopts high resolution 3D seismic data, develops multi-combined means, which contains seismic data vertical section and horizontal section interpretation, 3D data volume fault interpretation, surface sliced horizon and fault interpretation and 3D visualization interpretation and so on, and also colligates other technologies such as marginal detection, coherent volume, dip and azimuth angle attribute analysis and varying velocity mapping technique, completes high-resolution 3D seismic data fine structure interpretation in southern area of WUERXUN Depression in HAILAER Basin, carries out structure framework and structure feature of WUNAN area, finds abundant of formation fault, block fault, fault nosing structure, which provides reliable basic data for this area's potential target estimation, drilling target optimization, rolling exploitation.Aim at the difficulties such as weak reflection energy, poor Signal-to-Noise, indistinct seismic reflection characteristic of sand body reservoir interior structure, difficult to identify the fan body due to area's structure complexity and reservoir imbedded deep, the paper is based on seismic attributes analysis technique and frequency division interpretation technique, summarizes and completes 3D visualization fine depict sand body horizontal distribution technique. The method starts at fine calibrating oil layer position and fixing on reflection layer composite wave feature and seismic analysis window range of oil layer, develops a series of technique flows, such as frequency division processing, optimizing seismic attributes volume, fixing seed point in the level volume to auto-tracing and picking seismic attributes, resuming sand body's spatial distribution with reverse level method, and quickly resumes the reservoir's spatial through-going shape. Hereby, the results are 5 lithostromes in lower part of Nantunâ…¢Formation, 4 lithostromes in lower part of Nantunâ…¡Formation, 6 lithostromes in lower part of Nantunâ… Formation, 5 lithostromes in second part of Nantunâ…¡Formation, 5 lithostromes in second part of Nantunâ… Formation, which effectively settle the difficulties to indentify and depict the fan body in southern area of WUERXUN Depression in HAILAER Basin, and provides drilling target for lithologic deposit exploration in southern area of WUERXUN Depression.Do the searching works of 3D seismic fine interpretation technique in southern area of WUERXUN Depression, a suit of technique flow was basically formed to be fit for complex depression basin 3D seismic fine structure interpretation and lithology body target identification and depiction, which is also fit for other depression basin with universality.