D. Seller, C. Edmiston, O. Torres and J. Goetz
Halliburton Logging Services
ABSTRACT
A resurgence of interest in the BoreHole TeleViewer (BHTV) has been fueled by the industrv’s interest in evaluating thinly laminated zones of previously overlooked potential reservoirs and for a more graphic description of fractures and their orientation. The original BHTV introduced in the 1960s was ahead of its time. Supporting technologies were in their infancies. A convergence of several technologies today has made the new Circumferential Acoustic Scanning Tool (CAST) a viable imaging device. These technologies include transducer design, downhole electronics, uphole storage capacity, computer capabilities, image processing enhancements, pattern recognition and image display hardware.
Post-processing of field data yields both qualitative and quantitative information. Image enhancement allows the user to highlight different features selectively, and to sharpen and equalize the image. Pattern recognition produces an automatic dip calculation from the image and a resultant tadpole dip log. Interactive graphics allow the user to edit and selectively process the data. Three dimensional representations display the image from different perspective points to give a more true-to-life representation. An analysis of borehole geometry infers in-situ stress direction. High resolution acoustic calipers give a measure of borehole micro-rugosity.
Analysis of field log images from both fractured and thinly bedded formations is presented in this paper. Various image processing techniques are used to aid the interpretation. An integration of other log data is used in the analysis.