Paper: Drilling Research At Sandia Laboratories

Drilling is required for the exploration and production of almost all forms of energy and mineral resources found in the earth. Current drilling activity in this country is large and working near the industrial capacity. For example, the petroleum industry alone drilled approximately 145 million feet of hole in 1974 at an average cost of $24 per foot. The uranium industry drilled an additional 22 million feet to bring the total drilling cost to almost $4 billion in 1974. This figure was exceeded in 1975 and projections for 1976 are higher still. Using today's rotary technology, the cost of drilling for petroleum increases exponentially with hole depth as shown in Fig. I. The future development of geothermal resources will pose even more severe problems to the drilling industry. The more competent basement rocks at elevated temperatures are more difficult to drill, and footage costs are factors of two to four higher than for comparable depth sedimentary drilling. If improved drilling technology is not developed, this expense, coupled with the shortage of rigs and trained crews, could severely limit the timely development of this resource. Drilling technology could become a limiting factor in future energy development if ways are not found to increase the footage drilled and reduce the costs per foot. Significantly increasing the active rig count does not seem to be a viable option due to the very long lead time associated with new rig deliveries and the severe shortage of trained personnel.