渤中凹陷西南环潜山复杂带断层识别

A new fault identification method for complex zones around the buried hill in Southwestern Bozhong Sag

左中航 姜利群 蔡纪琰 吴俊刚 高磊

ZUO Zhonghang JIANG Liqun CAI Jiyan WU Jungang GAO Lei

中海石油(中国)有限公司天津分公司渤海石油研究院 中海石油(中国)有限公司天津分公司勘探部

Bohai Petroleum Research Institute, Tianjin Branch of China National Offshore Oil Co., Ltd., Tianjin 300459 China Exploration Department, Tianjin Branch of China National Offshore Oil Co., Ltd., Tianjin 300459, China

常规的相干、方差、边缘检测等断层识别方法主要依赖等时地层切片，而潜山内幕埋藏深、信噪比低、地层高陡、断裂复杂，使得上述常规方法难以获得可靠结果。基于自适应中值滤波和相干分析，提出了一种新的基于地层倾角相干分析的断层识别方法，其核心是运用地层倾角和方位角属性体对相干体计算进行方向约束，获得带地层方向的优势相干体，同时建立基于地层倾角的相干切片从而突出各级断层。该方法的优点在于深化了相干分析，克服了原有相干计算的局限性、水平等时切片内幕断层显示的不准确性等问题。实际资料的计算结果表明，该方法简单易行，可以有效识别高陡复杂带的大、中、小等不同尺度的断层，断层识别率显著高于常规相干体方法。

Conventional fault identification methods (e.g.coherence, variance and edge detection) mainly rely on isochronous stratal slice.As for inner buried hills, however, these conventional methods can hardly provide the reliable identification results for they are characterized by large burial depth, low signal-to-noise ratio, high-dip formation and complex fault.In this paper, a new fault identification method based on dip coherence analysis was proposed based on adaptive median filtering and coherence analysis.The core of this method is to take the attribute cube of stratigraphic dip and azimuth as the direction constraint to the calculation of coherence cube so as to obtain dominant coherence cubes with stratigraphic direction, while establishing the coherence slice based on stratigraphic dip so as to highlight the faults of all levels.The advantage of this method is that it deepens the coherence analysis, overcomes the limitation of the original coherence calculation and solves the inaccuracy of the horizontal isochronal slice inside buried hill.The calculation results of actual data show that this method is simple and feasible and can effectively identify large, medium and small faults in high-dip complex zones, and its fault identification accuracy is significantly higher than that of conventional coherence cube method.

10.13639/j.odpt.2018.S0.005