Abstract: X-ray Computed Tomography (CT) Applied in Routine Core Analysis: Examples from New Guinea and the North West Shelf, Australia

Lee Coshell, James Brown, John K. Warren

X-ray Computed Tomography (CT) is a powerful technique for nondestructive 3-D analyses of cores. It provides sedimentological and structural information that is difficult or impossible to obtain by other means. Nevertheless, x-ray CT has until recently lacked acceptance by the petroleum industry as a routine core analysis tool. The reasons for this stem mainly from resolution limitations of second generation CT scanners used to carry out early research on cores, a lack of image analysis software specific to core analysis, and the relatively high cost of scanning.

Increased emphasis is now being placed on detailed reservoir characterization and the need to better define heterogeneity on the core scale. Core analysis has become more sophisticated and expensive. These factors, combined with more advanced CT scanner hardware and image analysis software, have resulted in a resurgence of company interest in x-ray CT. Indeed, the technique has now evolved to where it plays an increasingly important part in the process of routine core analysis.

We present examples from New Guinea and the North West Shelf, Australia, where x-ray CT is being successfully used to scan sealed core for selection of core plug sites, determination of plug integrity prior to special core analysis, and assessment of formation damage through testing of various mud systems flushed through core plugs. Drilling-induced damage is also being quickly assessed through the scanning of sealed core. In addition, minipermeameter results have been related to CT images as a means by which core-scale permeability pathways can be mapped in 3-D.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994