When the oil business started, the main problem was finding the stuff. Colonel (self-promoted) Drake drilled the first oil well in Oil Creek, Pennsylvania. Hence, the smart money was to look for oil along creeks and streams–the era of the creekologists. Well, that did not work out too well, so the next place to look were various lumps and bumps, which were known as anticlines. That worked fine, mostly, and the Spindletop discovery resulted from that geology.