准噶尔盆地北缘春晖油田不整合圈闭边界识别

Identification of the Unconformity Trap Boundaries in Chunhui Oilfield in Northern Margin of Junggar Basin

准噶尔盆地北缘春晖油田浅层主要发育超覆-削蚀油藏,准确确定地层超覆线和削蚀线位置对于指导油气勘探有重要意义。地层超覆线和削蚀线正演模拟结果表明,受地震资料垂向分辨率的限制,地震识别超覆线和削蚀线与实际地层超覆线和削蚀线存在一定的外推距离,该外推距离随地层倾角的增大而减小,随地层纵波速度的增大而增大,随地震频率的增大而减小,从而建立了适合研究区的外推公式,落实了地层超覆线和削蚀线的准确位置。

The overlap-erosion oil reservoir is the main type in shallow overlap-erosion belt of Chunhui oilfield in Junggar basin. Accurate determination of the stratigraphic overlap-erosion line is of great significance for guiding oil-gas exploration here. It is indicated by forward modeling that there exists an extrapolating distance between the seismic overlap-erosion line and the real line constrained by seismic vertical resolution, and the distance decreases with stratigraphic inclination angle increasing, increases with stratum velocity increasing and decreases with seismic frequency increasing. Therefore, this paper establishes the extrapolating equations suitable for the studied area and determines accurately the positions of the overlap-erosion line.