ABSTRACT: Development of a Doppler Borehole Televiewer for imaging of flow distribution in borehole wall
Saito, Jin and Hiroaki Niitsuma , Tohoku University, Sendai, Japan
Doppler Borehole Televiewer (DBHTV) to quantitatively evaluate permeability of independent fracture is beeing developed in Tohoku University. In the DBHTV, back-scattered waves from fine particles in borehole fluid such as drill mud or a cuttings are detected with the reflected waves from borehole wall, and Doppler shift of back-scattered waves are used in velocity estimation. Method for estimation of distribution of Doppler shift was examined using a model fracture in laboratory experiment, and we found that the pulse-pair method has good ability to estimate Doppler shift for limited number of sampled data. We experimentally investigated effect of location of sampling volume, method for quantitative estimation of flow from Doppler shift, and effect of scanning of transducer. It has been shown from this study that the location of permeable fracture, fluid flow and fluid volume can be visualized using the DBHTV.
AAPG Search and Discovery Article #90913©2000 AAPG International Conference and Exhibition, Bali, Indonesia