Abstract: Methods of determining stimulation related characteristics of a subterranean zone penetrated by a well bore prior to stimulating the zone are provided. The methods basically comprise injecting a small amount of a stimulation fluid having an X-ray contrasting agent admixed therewith into the zone and then obtaining one or more preserved core samples from the zone. The core samples are scanned with X-rays and computed tomographic images are produced for determining the characteristics of the zone.