摘要
目前渤海油田新近系已全面转入岩性勘探,烃检技术在其中发挥着重要作用。常规叠后烃检方法对厚水层引起的假亮点难以消除、对薄油层无法有效识别,因此,常规叠后烃检结果多解性强、可信度低。本文提出了适用于渤海新近系储层特征的高频亮点加权含烃检测方法,该方法能有效区分油、水层形成的地震真、假亮点。首先,应用数值正演模拟技术对影响频谱特征的主导因素和油水频谱特征差异进行论证,结果表明,薄油层和厚水层的关键属性为“高频亮点”。在此基础上,建立了适合渤海新近系含油气储层的包括地震数据目标优化处理、储层预测、高精度属性计算、高频亮点属性加权的含油气综合检测技术系列。该方法有效压制了厚水层假亮点,薄油层的识别精度提高了20%,大幅增强了烃检结果的可信度。在渤海油田多个构造和油田评价应用的结果表明,该方法能较好压制厚水层,识别薄油层,方法可行有效,在类似油田有较强的借鉴应用价值。
Hydrocarbon detection plays an important role in lithologic reservoir exploration in the Neogene System,the Bohai oilfield.Poststack hydrocarbon detection suffers from great uncertainties and low credibility owing to the ticklish problem of how to diagnose false bright spots related to thick water layers and identify thin oil layers.To distinguish between oil-related bright spots and water-related analogues,we propose a high-frequency bright-spot weighting technique for hydrocarbon detection in Neogene reservoirs,the Bohai Sea.Based on forward modeling,we discuss major controls on frequency spectrum and differences between oil and water spectra;high-frequency bright spot is demonstrated to be a key attribute to discriminate between thin oil layers and thick water layers.Based on this idea,we establish a portfolio of hydrocarbon detection techniques,including target-oriented seismic data processing,reservoir prediction,high-precision attribute extraction,and weighted attribute,which are feasible for Neogene reservoir exploration in the Bohai Sea.Bright spots related to thick water layers could be effectively suppressed,and the accuracy of thin oil reservoir detection increases by 20%.This technique is successfully applied to pre-drilling evaluation of several structures and prospects in the Bohai oilfield to identify thin oil layers.Research results may be used for reference in the oilfields with similar geologic setting.
作者
李才
张平平
侯栋甲
熊煜
LI Cai;ZHANG Pingping;HOU Dongjia;XIONG Yu(Bohai Petroleum Research Institute,Tianjin Branch of CNOOC LTD.,Tianjin 300459,China)
出处
《石油物探》
CSCD
北大核心
2023年第6期1182-1193,共12页
Geophysical Prospecting For Petroleum
基金
中海石油(中国)有限公司“七年行动计划”重大科技专项课题(CNOOC-KJ-135ZDXM36TJ08TJ)资助。
关键词
烃检
高频亮点
低频增强
匹配追踪
支持向量机
hydrocarbon detection
high-frequency bright spot
low frequency enhancement
matching pursuit
support vector machine
