川南大塔场地区阳新统碳酸盐岩储层裂缝地震预测

发布时间：2018-06-18 11:23

本文选题：碳酸盐岩 + 缝洞　；参考：《成都理工大学》2015年硕士论文

【摘要】：研究区位于我国西南部重要的天然气产出基地四川盆地。该区油气地质勘探,始于建国初期,至今经历了几十年的勘探开发实践,由浅层至深层发现了侏罗系、三叠系以及更老的二叠系气藏。近年来随着四川盆地油气勘探的进展,二叠系海相地层显现了较大的勘探潜力,加上目前气田内阳新统的生产井基本处于关停状态,因此有必要对阳新统的剩余资源量进行开发。研究区储层岩性主要为致密灰岩,基质孔隙度和渗透率低,储存空间主要由裂缝、孔洞组成。由于溶蚀和构造运动等作用形成的缝洞系统极其复杂,具有大小悬殊、形态多样、分布不均、成因及形成时期不同等特点,给本区的油气预测带来一定的困难。本文首先运用钻井、测井、岩心、地震等资料对阳新统储层地质特征综合分析,然后通过地震正演模拟和工区典型老井的地震剖面来分析缝洞型储层在地震剖面上的响应特征,总结了地震方法对缝洞发育带的可识别性及识别原理。采用了随机地震反演技术来预测储层的分布规律。其次分别运用叠后地震资料属性分析技术和叠前裂缝密度检测技术进行缝洞发育带的预测和描述。最后运用频谱衰减技术和叠前AVO技术进行储层的含流体性评价研究。分析各种方法的应用效果,并将成果与钻井、生产资料进行对比分析,最终达到预测出储层有利区域的目的。通过本次研究工作,在本区碳酸盐岩储层缝洞体预测研究方面主要取得了以下几个方面的认识:(1)在本区油气预测中必须找到裂缝、溶蚀孔同时发育的区域,是获得工业性气流的保障。通过钻井、测井、岩心、地震等资料分析,本区的储层主要位于茅口组茅三、茅二段,为一套海相碳酸盐岩地层。岩性主要为灰岩,质地较纯,横向沉积稳定,基岩致密,基质孔隙度和渗透率很低,但裂缝渗透率很高。储集空间主要由溶蚀孔、洞组成,裂缝为渗流通道。(2)缝洞体在震剖面上的响应特征主要表现在地震波速度、振幅、频率均发生明显变化。通过地震正演模拟和反演分析研究表明:缝洞体速度小于围岩速度。地震振幅表现在同相轴分叉合并、时差增大、波形畸变、杂乱或空白反射、短轴强峰强谷等特征。当地震波穿过含有流体缝洞体时,高频成分会很快衰减掉,地震主频向低频方向移动,频带宽度变窄。(3)阳新统的裂缝带的发育与断层紧密相关,地震振幅属性对裂缝更为敏感。在地震勘探提供精细解释构造成果和断层分布的基础上,通过运用叠后相干技术、曲率属性和叠前P波方位各向异性裂缝检测综合预测裂缝发育带所取得的效果较好。本文通过储层地震预测方法研究与本区的实际勘探相结合,证明了方法的适用性和有效性,促进了本区的碳酸盐岩储层勘探的发展,也为我们深入研究储层裂缝的识别积累了丰富的经验
[Abstract]:The research area is located in the Sichuan Basin, an important natural gas production base in the southwest of China. Oil and gas geological exploration in this area began at the early stage of the founding of the people's Republic of China, and has gone through several decades of exploration and development practice. Jurassic, Triassic and older Permian gas reservoirs have been discovered from shallow to deep layers. In recent years, with the development of oil and gas exploration in Sichuan Basin, the Permian marine strata have shown great exploration potential, and the production wells of the present gas field in Yangxin are basically closed down. Therefore, it is necessary to develop the remaining resources of Yangxin. The reservoir lithology in the study area is mainly dense limestone, the matrix porosity and permeability are low, and the storage space is mainly composed of fractures and pores. The fracture and cavity system formed by dissolution and tectonic movement is extremely complex, with the characteristics of great difference in size, variety in shape, uneven distribution, and different origin and formation period, which brings some difficulties to the prediction of oil and gas in this area. In this paper, the geological characteristics of Yangxin reservoir are analyzed synthetically by drilling, logging, core and seismic data, and then the response characteristics of fractured and cavernous reservoirs on seismic profile are analyzed by seismic forward modeling and seismic profile of typical old wells in the working area. The recognition principle of seismic method for fracture and cavity development zone is summarized. Stochastic seismic inversion technique is used to predict reservoir distribution. Secondly, the post-stack seismic data attribute analysis technique and prestack fracture density detection technique are used to predict and describe the fracture and cavity development zone. Finally, spectrum attenuation technique and pre-stack AVO technique are used to evaluate the fluidity of reservoir. The application effect of various methods is analyzed, and the results are compared with drilling and production materials, and the purpose of predicting favorable reservoir area is finally achieved. Through this research work, in the area carbonate reservoir fracture-cavity body prediction research has mainly obtained the following several aspects understanding: 1) in this area oil and gas prediction must find the fracture, the dissolution pore simultaneously develops the area, Is to obtain the protection of industrial airflow. Through the analysis of drilling, logging, core and seismic data, the reservoir in this area is mainly located in Mao-3 and Mao-2 of Maokou formation, which is a set of marine carbonate strata. The lithology is mainly limestone with pure texture, stable lateral deposition, dense bedrock, low porosity and permeability of matrix, but high fracture permeability. The reservoir space is mainly composed of dissolved pores and caverns, and the fractures are seepage channels. The response characteristics of the fractured voids on the seismic profile are mainly reflected in the obvious changes of seismic wave velocity, amplitude and frequency. Through seismic forward modeling and inversion analysis, it is shown that the velocity of fractures and cavities is smaller than that of surrounding rock. The seismic amplitude is characterized by in-phase axial bifurcation, increased time difference, waveform distortion, clutter or blank reflection, short axis strong peak and valley, and so on. When the seismic wave passes through the body containing fluid cracks, the high frequency component will decay quickly, the main frequency of the earthquake will move to the direction of low frequency, and the frequency band width will become narrower.) the development of the fracture zone of Yangxin series is closely related to the fault, and the seismic amplitude attribute is more sensitive to the fracture. On the basis of the fine structural interpretation and fault distribution provided by seismic exploration, the comprehensive prediction of fracture development zone by using poststack coherence technique, curvature attribute and prestack P wave azimuthal anisotropic fracture detection is better. Through the research of reservoir seismic prediction method and the actual exploration in this area, this paper proves the applicability and validity of the method, and promotes the development of carbonate reservoir exploration in this area. It also accumulates rich experience for us to study the identification of reservoir fractures in depth.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P618.13;P631.4

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