Q Estimation From Zero-Offset VSP Data Under the Constraint of Q Forward Modeling

doi:10.7657/XJPG20200415

Abstract

Abstract:

As the deepening of target zones for oil and gas exploration, spherical diffusion, transmission loss and environmental noise may lead to the change of VSP first arrival wavelet and then the Q value obtained from conventional estimation method may not be accurate. Therefore, based on the zero-offset VSP data of Well TP327 in Tuofutai area of Tarim basin and considering the effects of transmission loss and spherical diffusion, this paper proposes a method to estimate Q-value by using zero-offset VSP data under the constraint of Q forward modelling. By establishing a layered geological model based on P- and S-wave velocities and densities in the work area, the method uses ray tracing method and Q forward modeling results from an earth absorption model to modify the initial Q values estimated from spectral ratio method and empirical formula method, allowing Q forward modeling results matching with the actual seismic wave attenuation record on frequency spectrum. Then a more accurate Q model has been obtained. The Q estimation result in Well TP327 show that in shallow strata the result is close to that obtained from Liqingzhong’s empirical formula, but in middle and deep strata, the results obtained from the two methods are greatly different. The spectrum of the wavelet constrained by Q forward modeling result well fits with that of the actual wavelet of VSP data, proving that the Q value obtained from the method constrained by Q forward modeling is more reliable. The Q model obtained from the method can significantly improve the resolution of seismic data through performing inverse Q filtering for the seismic data in the study area, which helps to improve the identification accuracy for fractures and vugs in the carbonate strata.

Key words: zero offset, VSP data, first arrival wavelet, Q forward modeling, spectrum ratio method, earth absorption model, amplitude attenuation, inverse Q filter, resolution

CLC Number:

P631

MA Xuejun, MOU Qi, LI Haiying, YANG Zichuan, ZHANG Xueying. Q Estimation From Zero-Offset VSP Data Under the Constraint of Q Forward Modeling[J]. Xinjiang Petroleum Geology, 2020, 41(4): 483-490.

Figures/Tables 10

Fig. 1.

Fig. 2.

Fig. 3.

Fig. 4.

Fig. 5.

Fig. 6.

Fig. 7.

Fig. 8.

Fig. 9.

Fig. 10.

References 28

[1]	蒋立, 王晓涛, 谭佳, 等. 沙漠区近地表和中深层一体化Q模型的建立及应用[J]. 新疆石油地质, 2017,38(1):91-95.
	JIANG Li, WANG Xiaotao, TAN Jia, et al. Establishment and application of integrated near-surface and subsurface Q model in desert area[J]. Xinjiang Petroleum Geology, 2017,38(1):91-95.
[2]	冯玮, 胡天跃, 常丁月, 等. 基于时变子波的品质因子估计[J]. 石油地球物理勘探, 2018,53(1):136-146.
	FENG Wei, HU Tianyue, CHANG Dingyue, et al. Quality factor Q estimation based on time-varying wavelet[J]. Oil Geophysical Prospecting, 2018,53(1):136-146.
[3]	FUTTERMAN W I. Dispersive body waves[J]. Journal of Geophysical Research, 1962,67(13):5 279-5 291. doi: 10.1029/JZ067i013p05279
[4]	李合群, 孟小红, 赵波. 地震数据Q吸收补偿应用研究[J]. 石油地球物理勘探, 2010,45(2):190-195.
	LI Hequn, MENG Xiaohong, ZHAO Bo. Application studies on Q absorption and compensation for seismic data[J]. Oil Geophysical Prospecting, 2010,45(2):190-195.
[5]	郭建, 王咸彬, 胡中平, 等. Q补偿技术在提高地震分辨率中的应用:以准噶尔盆地Y1井区为例[J]. 石油物探, 2007,46(5):509-513.
	GUO Jian, WANG Xianbin, HU Zhongping, et al. Application of Q compensation technique in improving seismic resolution:case study of Y1 well area,Junggar basin[J]. Geophysical Prospecting for Petroleum, 2007,46(5):509-513.
[6]	蒋立, 毛海波, 刘宏杰, 等. 基于连续小波的地层品质因子计算方法[J]. 新疆石油地质, 2018,39(6):722-726.
	JINAG Li, MAO Haibo, LIU Hongjie, et al. Calculation method of formation quality factor based on continuous wavelet[J]. Xinjiang Petroleum Geology, 2018,39(6):722-726.
[7]	WINKLER K W, NUR A. Seismic attenuation:effects of pores and frictional sliding[J]. Geophysics, 1982,47(1):1-15.
[8]	高静怀, 杨森林. 利用零偏移VSP资料估计介质品质因子方法研究[J]. 地球物理学报, 2007,50(4):1 198-1 209.
	GAO Jinghuai, YANG Senlin. On the method of quality factors estimation from zero-offset VSP data[J]. Chinese Journal of Geophysics, 2007,50(4):1 198-1 209.
[9]	赵海波, 陈百军, 李奎周, 等. 黏弹性介质VSP记录模拟及在估算Q值研究中应用[J]. 地球物理学报, 2011,54(2):329-335.
	ZHAO Haibo, CHEN Baijun, LI Kuizhou, et al. VSP record numerical modeling in viscoelastic media and its application in the study of Q-value estimation method[J]. Chinese Journal of Geophysics, 2011,54(2):329-335.
[10]	江小根, 熊章强, 张大洲, 等. 基于频谱的两种品质因子提取方法对比分析[J]. 物探化探计算技术, 2019,41(5):572-579.
	JIANG Xiaogen, XIONG Zhangqiang, ZHANG Dazhou, et al. Contrast and analysis of two quality factor extraction methods based on spectrum[J]. Computing Techniques for Geophysical and Geochemical Exploration, 2019,41(5):572-579.
[11]	王静, 姚正新, 张彦斌, 等. VSP全井段Q值估计[J]. 石油地球物理勘探, 2018,53(增刊2):58-64.
	WANG Jing, YAO Zhengxin, ZHANG Yanbin, et al. Whole-well length VSP Q estimation[J]. Oil Geophysical Prospecting, 2018,53(Supp.2):58-64.
[12]	QUAN Y, HARRIS J M. Seismic attenuation tomography using frequency shift method[J]. Geophysics, 1997,62(3):895-905.
[13]	WU Zongwei, WU Yijia, GUO Si, et al. Q-factor estimation in CMP gather and the continuous spectral ratio slope method[J]. Applied Geophysics, 2018,15(3/4):481-490.
[14]	张大伟, 孙赞东, 王学军, 等. 利用零井源距VSP资料进行品质因子反演[J]. 石油地球物理勘探, 2011,46(增刊1):47-52.
	ZHANG Dawei, SUN Zandong, WANG Xuejun, et al. Q-factor inversion and calculation using zero-offset VSP data[J]. Oil Geophysical Prospecting, 2011,46(Supp.1):47-52.
[15]	宫同举, 孙成禹, 彭洪超, 等. 几种提取品质因子方法的对比分析[J]. 勘探地球物理进展, 2009,32(4):252-256.
	GONG Tongju, SUN Chengyu, PENG Hongchao, et al. Comparison of several computational methods of quality factor[J]. Progress in Exploration Geophysics, 2009,32(4):252-256.
[16]	武银婷, 朱光明, 刘伊克, 等. 零偏VSP反演Q值CFS方法及影响因素研究[J]. 地球物理学进展, 2010,25(6):1 897-1 904.
	WU Yinting, ZHU Guangming, LIU Yike, et al. Study on CFS method in Q inversion using zero-offset VSP data[J]. Progress in Geophysics, 2010,25(6):1 897-1 904.
[17]	武银婷, 朱光明. 基于零偏VSP三种Q值反演方法对比分析及应用[J]. 地球物理学进展, 2017,32(5):2 107-2 114.
	WU Yinting, ZHU Guangming. Comparison and application of three different methods for inversing Q value with zero-offset VSP data[J]. Progress in Geophysics, 2017,32(5):2 107-2 114.
[18]	TONN R. 计算Q值七种方法的比较[J]. 张树林,译. 国外油气勘探, 1991,3(6):89-97.
	TONN R. Comparison of seven methods for the computation of Q[J]. Translated by ZHANG Shulin. Equipment for Geophysical Prospecting, 1991,3(6):89-97.
[19]	陆基孟. 地震勘探原理[M]. 山东东营: 石油大学出版社, 1993: 340-352.
	LU Jimeng. The principle of seismic exploration[M]. Dongying,Shandong： China University of Petroleum Press, 1993: 340-352.
[20]	云美厚, 丁伟. 地震子波频率浅析[J]. 石油物探, 2005,44(6):578-581.
	YUN Meihou, DING Wei. Analysis of seismic wavelet frequency[J]. Geophysical Prospecting for Petroleum, 2005,44(6):578-581.
[21]	高静怀, 汪文秉, 朱光明, 等. 地震资料处理中小波函数的选取研究[J]. 地球物理学报, 1996,39(3):393-394.
	GAO Jinghuai, WANG Wenbing, ZHU Guangming, et al. On the choice of wavelet functions for seismic data processing[J]. Chinese Journal of Geophysics, 1996,39(3):393-394.
[22]	芦俊. KEL-TI介质的地震波场响应与成像方法研究[D]. 北京:中国科学院地质与地球物理研究所, 2008.
	LU Jun. The research of seismic responses and imaging methods in KEL-TI medium[D]. Beijing:Institute of Geology and Geophysics, 2008.
[23]	王洪求, 刘伟方, 郑多明, 等. 塔里木盆地奥陶系碳酸盐岩“非串珠状”缝洞型储层类型及成因[J]. 天然气地球科学, 2011,22(6):982-988.
	WANG Hongqiu, LIU Weifang, ZHENG Duoming, et al. Types and causes of “none-string beads” fracture-cavity reservoirs in Ordovician carbonate of Tarim basin[J]. Natural Gas Geoscience, 2011,22(6):982-988.
[24]	田军. 塔里木盆地油气勘探成果与勘探方向[J]. 新疆石油地质, 2019,40(1):1-11.
	TIAN Jun. Petroleum exploration achievements and future targets of Tarim basin[J]. Xinjiang Petroleum Geology, 2019,40(1):1-11.
[25]	邓兴梁, 罗新生, 刘永福, 等. 缝洞型碳酸盐岩定容油藏形成机理及开发技术[J]. 新疆石油地质, 2019,40(1):79-83.
	DENG Xingliang, LUO Xinsheng, LIU Yongfu, et al. Forming mechanism and development measures of constant-volume fractured-vuggy carbonate oil reservoirs[J]. Xinjiang Petroleum Geology, 2019,40(1):79-83.
[26]	杨子川, 陶磊, 李海英, 等. 塔河油田S48井区流体多波属性综合预测[J]. 新疆石油地质, 2018,39(6):742-747.
	YANG Zichuan, TAO Lei, LI Haiying, et al. Comprehensive fluid prediction with multi-wave attribute seismic technology in Wellblock S48,Tahe oilfield[J]. Xinjiang Petroleum Geology, 2018,39(6):742-747.
[27]	王咸彬. 井控地震资料处理技术及其在LS地区的应用[J]. 石油物探, 2008,47(4):381-386.
	WANG Xianbin. Well-control seismic data processing and its application in LS area[J]. Geophysical Prospecting for Petroleum, 2008,47(4):381-386.
[28]	吕牛顿. 连续介质中任意炮检距的球面扩散补偿因子[J]. 石油物探, 1986,25(2):7-11.
	LÜ Niudun. Compensation factor of spherical diffusion with arbitrary offsets in continuous medium[J]. Geophysical Prospecting for Petroleum, 1986,25(2):7-11.