Application of four-component dipole shear refl ection imaging to interpret the geological structure around a deviated well*
Lee Sheng-Qing, Chen Ming, Gu Xi-Hao, Su Yuan-Da, and Tang Xiao-Ming
1. School of Geosciences, China University of Petroleum, Qingdao 266580, China.
2. Key Laboratory of Deep Oil and Gas, China University of petroleum, Qingdao 266580.
3. Zhanjiang Branch of CNOOC Ltd., Zhanjiang 524057, China.
4. China Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology,Qingdao 266071, China.
Abstract Acoustic reflection imaging in deep water wells is a new application scope for offshore hydrocarbon exploration. Two-dimensional (2D) geological structure images can be obtained away from a one-dimensional (1D) borehole using single-well acoustic reflection imaging. Based on the directivity of dipole source and four-component dipole data, one can achieve the azimuth detection and the three-dimensional (3D) structural information around the wellbore can be obtained. We first perform matrix rotation on the field fourcomponent data. Then, a series of processing steps are applied to the rotated dipole data to obtain the reflector image. According to the above dipole shear-wave imaging principle, we used four-component cross-dipole logging data from a deviated well in the South China Sea to image geological structures within 50 m of a deviated well, which can delineate the structural configuration and determine its orientation. The configuration of near-borehole bedding boundaries and fault structures from shear-wave imaging results agrees with those from the Inline and Xline seismic profiles of the study area. In addition, the configuration and orientation of the fault structure images are consistent with regional stress maps and the results of the borehole stress anisotropy analysis. Furthermore, the dip azimuth of the bedding boundary images was determined using borehole wall resistivity data. Results of this study indicate that integrating borehole acoustic refl ection with seismic imaging not only fi lls the gap between the two measurement scales but also accurately delineates geological structures in the borehole vicinity.
This work was supported by the National Natural Science Foundation of China (Nos. 41804124, 41774138, 41804121,41604109), China Academy of Sciences Strategic Leading Science and Technology Project (Grant Nos. XDA14020304, XDA14020302), Shandong Provincial Natural Science Foundation, China (No. ZR2019BD039), Shandong Province Postdoctoral Innovation Project (No. 201901011) and China Postdoctoral Science Foundation (Grant Nos. 2019T120615,2018M632745).
About author: Lee Sheng-Qing received his Ph.D. degree from China Petroleum University (East China) in 2017. He is currently a postdoctoral fellow at China Petroleum University (East China), and he is mainly engaged in the study of borehole acoustic theory, methodology and field data interpretation, and gas hydrate logging. Email: shidalishengqing@yeah.net.
Cite this article:
. Application of four-component dipole shear refl ection imaging to interpret the geological structure around a deviated well*[J]. APPLIED GEOPHYSICS, 2019, 16(3): 293-302.
2019, Vol. 16 
