An effective data processing flow for the acoustic reflection image logging

Abstract

A B S T R A C TRecent studies have revealed the great potential of acoustic reflection logging in detecting near borehole fractures and vugs. The new design of acoustic reflection imaging tool with a closest spacing of 10.6m and a certain degree of phase steering makes it easier to extract the reflection signals from the borehole mode waves. For field applications of the tool, we had developed the corresponding processing software: Acoustic Reflection Imaging. In this paper, we have further developed an effective data processing flow by employing multi-scale slowness-time-coherence for reflection wave extraction and incorporating reverse time migration for imaging complicated subtle structures with the strong effects of borehole environment. Applications of the processing flow to synthetic data of acoustic reflection logging in a fractured formation model and interface model with fluid filled borehole generated by 2D finite difference method, and to the physical modelling data from a laboratory water tank, as well as to the field data from two wells in a western Chinese oil field, demonstrate the validity and capability of our multi-scale slowness-time-coherence and reverse time migration algorithms.

Elastic least-squares migration for quantitative reflection imaging of fracture compliances

“…We consider borehole acoustic logging experiments in order to image and characterize fractures around a borehole. Single-well reflection imaging using acoustic logging data carefully removes direct and borehole-coupled waves to isolate reflected waves (Li et al, 2014b(Li et al, , 2017, and references therein). In the context of single-well reflection imaging, several imaging approaches have been tested, e.g., Kirchhoff depth migration, prestack f-k migration, beamforming migration, and reverse-time migration (Hornby et al, 1989;Tang and Patterson, 2009;Li and Yue, 2015;Gong et al, 2018).…”

Design of New-Style Book Trolley Based on Electric Drive for Library

“…Battery is an important part of the electric trolley, it not only provides power to start the vehicle, but also boost the role. Battery is one of the most important car parts of trolley, its quality directly affects the operation of the electric trolley [4][5][6]. The design of the trolley is based on the specific working hours and the parameters of motor (motor starting inrush current, average current work, the heavy load without prejudice to the maximum current of the motor, etc.)…”

Quantitative imaging of fractures around a borehole using linear slip theory and elastic least-squares migration

“…In order to image structures around a borehole, several migration methods have been tested in the context of single-well imaging, e.g., Kirchhoff depth migration, pre-stack f-k migration, beamforming migration, and reverse-time migration (Hornby, 1989;Tang and Patterson, 2009;Li and Yue, 2015;Gong et al, 2018). The fracture imaging was also tested using the reverse time migration in combination with a thin-layer fracture model (e.g., Li et al, 2014;Zhang et al, 2015).…”