After much persistence to find the origin of the word ‘wildcat’, I finally found it on Microsoft Encarta web site http://encarta.msn.com/encyclopedia_761576221_/Petroleum.html

(The term wildcatter comes from West Texas, where in the early 1920s drilling crews encountered many wildcats as they cleared locations for exploratory wells. Shot wildcats were hung on the oil derricks, and the wells became known as wildcat wells.)

Curosity killed the cats...... hmmm......