窄方位拖缆地震数据角度域成像处理及各向异性特征研究

Angle domain imaging processing and anisotropic characteristics of narrow azimuth streamer seismic data

由于海上油气勘探常用的拖缆地震数据的方位角范围比较窄,在利用各向异性特征进行裂缝性等复杂储层预测中,常常会受到限制。如何有效地增加海上拖缆数据的方位信息,提取到成像道集中的各向异性特征,通过各向异性反演对裂缝性复杂储层进行表征是关键。本文开展了针对窄方位拖缆地震数据的成像处理方法研究及其处理后道集数据的各向异性特征分析,建立了一套有效的海上窄方位拖缆数据的成像处理技术流程,并在此基础上开展了叠前各向异性反演以表征地下裂缝密度。窄方位的拖缆地震数据通过局部角度域全方位成像处理后,有效增加了地震数据的方位信息,并有能力输出得到角度域的全方位反射道集数据。论文选取珠江口盆地潜山油气藏勘探区的实际数据进行应用研究,全方位的偏移成像处理结果显著提升了潜山裂缝发育区的成像效果,同时利用全方位的角度域反射道集数据能够有效反演得到表征潜山内幕裂缝发育情况的参数。实际数据应用结果表明,基于窄方位拖缆地震数据的角度域成像处理及各向异性参数反演技术,可以很好地潜山裂缝储层描述,确定裂缝发育优质目标区,可在其他类似的潜山油气藏勘探开发中进行应用。

Due to the narrow azimuth range of offshore streamer seismic data,it is often limited in predicting complex reservoirs such as fractures using anisotropic features.Therefore,how to effectively increase the azimuth range of offshore streamer data,extract the anisotropic features of the imaging gather,and characterize fractured reservoirs is crucial.The paper studies the imaging processing methods for narrow azimuth streamer seismic data and analyzes the anisotropic characteristics of processed gathers.We establish a set of effective imaging processing flow of narrow azimuth towing cable data.On this basis,an effective prestack anisotropy inversion is carried out to show the underground fracture density.By using local angle domain imaging processing technology,the azimuth information of narrow azimuth streamer seismic data can be increased,and has the ability to output the omni-directional reflection gather data in the angle domain.In this paper,the seismic data of the buried hill exploration area in the Pearl River Mouth Basin are selected for application research,and the omni-directional migration imaging results significantly improve the imaging effect of the buried hill fracture development area.Moreover,the parameters characterizing the development of fractures in the buried hill can be effectively inverted by using omni-directional angle domain reflection gather data.The actual data application results indicate that the narrow azimuth streamer data imaging processing technology in the angle domain and the anisotropic parameter inversion method proposed in the paper can effectively describe buried hill fracture reservoirs,determine high-quality target areas for fracture development,and can be applied in the exploration and development of other similar buried hill hydrocarbon reservoirs.