精细构造解释及储层预测技术在轮南地区的应用

Application of fine structure interpretation and reservoir prediction technology in Lunnan area

轮南油田三叠系TⅠ—TⅢ油组为辫状河三角洲沉积,具有砂体横向变化快,储层厚度薄,油藏埋藏深的特点,且低级序断层较为发育,对研究区断层及储层发育特征认识尚不清楚,给油田开发带来了较大的影响.为了达到增储上产及寻找新的滚动开发目标的目的,综合多种技术手段对油田精细构造和储层预测进行了研究.利用时间切片技术、相干体刻画技术、蚂蚁追踪技术三种技术相结合的方法对不同级序的断层进行了精细解释,结合精细变速成图技术,落实了轮南地区精细构造特征.采用地震属性优选分析,流体检测技术与测井曲线重构反演技术结合的方法进行储层预测.通过属性优选发现,振幅属性能较好反映储层的变化,在TⅡ油组衰减梯度属性能较好反映流体的分布特征.优选出SP与AC曲线进行曲线重构,最终得出高分辨率的波阻抗反演剖面,纵向分辨率与横向分辨率均较高.通过对以上多种技术的综合研究,为轮南地区油藏精细开发及滚动勘探提供了依据.

The TⅠ—TⅢ oil group in Triassic in Lunnan oilfield is developed braided river delta which has the characteristics of sand body changing fast laterally,thin and deep buried reservoir. And lower order faults are well developed in the area. The distribution characteristics of reservoir and faults have not been clearly understood so far which have brought great difficult to oilfield development. In order to achieve the purpose of increasing oil production and searching for new rolling exploration and development target, fine structure interpretation and reservoir prediction have been studied in Lunnan oilfield integrating multiple technologies. Fine interpretation of faults in different levels is carried out with methods of time slice technology,coherent body characterization technology and ant tracking technology. The combination of time slice and coherent body interpretation technique are used to explain higher order faults,and lower order faults are explained by ant tracking technique so as to make the faults description more precise. Combined with fine variable speed mapping technology,the fine characteristics of structure in Lunnan oilfield is implemented. Based on the reservoir features of deep buried and laterally changing fast,reservoir prediction is studied using seismic attribute optimization,fluid detection and constrained inversion with reconstructed logging curve technology. Through seismic property optimization, it can be found that amplitude attribute can well reflect the change of reservoir and there is a certain correlation between the amplitude and thickness of reservoir.To identify fluid types of the reservoir,attenuation gradient attribute is chose which high frequency attenuation range of oil and water are different,oil and water can be well distinguished using attenuation gradient attribute in TⅡoil group. SP and AC curve are optimized in curve reconstruction process and high resolution of wave impedance inversion profile is obtained. The vertical resolution is higher which can achieve 3 - 5 meters. Through comprehensive research of above technologies, it provides the basis for fine development of oil reservoir and rolling exploration in this area.