I have stated that drilling is 80 percent knowledge and 20 percent luck. Bad luck happens when a driller encounters a loss zone, thus preventing the driller from finishing the hole. In these situations, it is up to the driller to create luck. Loss zones need to be dealt with quickly and efficiently. The following steps help prevent losing the borehole when drilling into a loss zone.
As a young mud engineer, I was invited by Ortman Drilling to help drill a geothermal test hole in downtown Indianapolis, at a site that would become a nature center. After evaluating the sample logs for the area, we expected to lose circulation at a depth of 88 feet and again at 105 feet. We removed the “luck factor” by having basic geologic knowledge of the area. I worked with this very same talented drill team at Ball State, and we encountered many lost circulation zones together. These guys were lost circulation experts for central Indiana. The team prepared to lose circulation once they drilled to 80 feet in the ground. At 88 feet, the drill bit encountered fractured limestone that immediately caused partial fluid loss. The experienced drill team agreed that understanding the loss zone, along with preparation, would be the key to drilling past the zone and completing the borehole.