论文详情
利用全频带常规蚂蚁追踪技术刻画断裂易出现横向连续性不强或平面断裂格局不明显的现象,造成断裂刻画与井间动态响应匹配度低。提出了基于匹配追踪频谱分解的分频相干体技术,并改进常规蚂蚁追踪技术流程,以提高断裂刻画精度。首先,以原始全频带地震数据为基础,采用匹配追踪频谱分解技术生成一系列分频体,并利用倾角导向滤波提高分频体的信噪比;然后,采用本征相干计算方法获得不同中心频率的分频相干体,对照不同分频剖面及目的层相干切片优选出某一分频相干体;最后对二次去噪后的分频相干体应用蚂蚁追踪技术并结合井区动静态资料,反复调整追踪参数,获得分频蚂蚁体。在此过程中,合理的频谱分解和去噪处理可提高中小尺度断裂的分辨率,本征相干计算和精调参数的蚂蚁追踪可提高中小尺度断裂的识别效果。将此技术应用于塔河油田T井区碳酸盐岩储层的中小尺度断裂识别,结果表明,相较于常规技术,该技术对断裂的刻画精度高,刻画结果与井间动态连通关系匹配性好,与地质认识吻合度高。
The conventional ant-tracking technique applied to fault characterization often results in weak transverse continuity or unobvious plane fracture patterns.It also leads to a poor matching relationship between the characterized faults and the inter-well dynamic response.To solve these issues,we proposed an improved ant-tracking technique based on matching-tracking spectral decomposition and improved the conventional workflow of ant-tracking.Firstly,the full spectral-band seismic data were decomposed into a series of frequency-divided data,and the dip steering filtering method was used to improve the signal-to-noise ratio of the initial seismic data.Then,the intrinsic coherence of seismic data in different frequency bands were calculated and extracted.We compared the profiles and the coherent slices of the target layer from different single-frequency data,so as to optimize the required coherent data.In addition,the data after further noise reduction were tracked by artificial ants,and the appropriate ant-tracking parameters were repeatedly adjusted based on dynamic or static data.Finally,dividing-frequency ant data were obtained by the aforementioned ant-tracking process.The resolution for medium-and small-scale fracture identification was improved through denoising and reasonable spectral decomposition.Furthermore,the effect of fault identification was enhanced by the ant-tracking parameters determination and intrinsic coherence calculation.This method was applied to the identification of medium-and small-scale faults in carbonate reservoirs in well area T in Tahe Oilfield.The results showed that the so-identified faults were consistent with the inter-well dynamic connectivity and geological interpretation.
中国石油化工股份有限公司科技部项目“顺北油田碳酸盐岩断裂体系及缝洞体刻画研究”项目(P17057-9)资助。