Chitali, Vivek¹, John Quirein¹, Tegwyn Perkins¹, Ron Stamm¹, Chuck Edmiston²
(1) Halliburton Energy Services, Houston, TX
(2) Halliburton Energy Services, Ft. Worth, TX

ABSTRACT: Reservoir Geological Application of a New, Improved Wireline Borehole Imager and New Image Interpretation Software: Examples from Fort Worth and Permian Basins

A new electrical wireline borehole imaging tool has been designed to obtain superior quality images even in high Rt:Rm environments. Tests have shown that the X-tended range micro-imager (the XRMI ™ tool) produces images with superior fidelity, even in highly resistive formations (Rt >> 2000 ohm-m) or very salty borehole fluids (Rm << 0.1 ohm-m) owing to its new state-of-the-art digital signal acquisition down-hole.
New image interpretation software has also been developed to estimate the sand and pay counts within the subsurface sedimentary sequence logged by the XRMI tool. The software exploits the tool’s ability to resolve thin laminations, sedimentary structures, and secondary porosity (vugs and fractures) in clastic as well as carbonate reservoirs. The software applies threshold techniques to the tool’s pre-processed high resolution images. Images are calibrated with the open hole logs, which determines valid threshold values for the images. The software generates cumulative sand and pay counts versus depth.
This paper shows several examples of the XRMI tool’s image logs from the Permian and Fort Worth Basins. The paper also presents a discussion of the technique to compute cumulative sand and pay counts (versus depth) using XRMI logs from a test well in the Fort Worth Basin. The results demonstrate the ability of the new tool and software to enable high resolution reservoir geological description and accurate computation of net-to-gross in boreholes characterized by a wide range of Rt:Rm ratios.

AAPG Search and Discovery Article #90026©2004 AAPG Annual Meeting, Dallas, Texas, April 18-21, 2004.