| 摘要: |
| 着眼于全球各地油田中大量的套管井和过套管远探测技术的应用前景,从理论分析和现场应用角度研究套管井中偶极横波远探测方法的可行性和实际应用中的有效性。与裸眼井相比,套管的存在会改变偶极声源的辐射特征和效率,使其有效频带向高频移动,但其辐射的声能未有量级上的改变,从理论上证明套管井中的偶极横波远探测,可以像裸眼井中的情况那样有效应用。为此对同一井段套前、套后的四分量偶极横波测井数据进行远探测成像处理和结果的对比分析。结果表明:即使是在两次测井时仪器方位完全不同的条件下,二者在地层反射体(实例中为裂缝体系)走向方位上的成像具有相当好的可重复性,验证该技术在实际应用中的可靠性。 |
| 关键词: 声波远探测 套管井 偶极声源 辐射效率 |
| DOI：10.3969/j.issn.1673-5005.2019.05.007 |
| 分类号: |
| 文献标识码:A |
| 基金项目:国家自然科学基金项目(41604109,8);中国科学院战略性先导科技专项(XDA14020304);山东省自然科学基金项目(ZR2019BD039) |
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| Theoretical analysis and field data application of through-casing dipole shear-wave imaging |
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TANG Xiaoming1,2, GU Xihao1, SU Yuanda1
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(1.School of Geosciences in China University of Petroleum(East China), Qingdao 266580, China;2.Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China)
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| Abstract: |
| Through-casing dipole shear-wave imaging is potentially a useful application for the vast amount of cased wells around the world. The feasibility of this application is analyzed using theoretical modeling and open-vs-cased-hole field data comparison. As the modeling results show, the presence of casing changes the radiation characteristics and the efficiency of the dipole source compared to the open-hole situation, and shifts the effective radiation to a higher frequency range. Despite these changes, the dipole shear-wave imaging technique can be used effectively in both open and cased boreholes. For further verification, the four-component cross-dipole acoustic data of a fractured formation were processed to image the formation fractures for the open and cased borehole, respectively.Despite the drastically different tool orientation of the two logging passes, repeatable fracture images were obtained along the fracture strike azimuth, suggesting the reliability of the application. |
| Key words: acoustic remote sensing logging cased borehole dipole source radiation efficiency |
