In the business of petroleum exploration, it’s hard to think of anything compared to migration which has enjoyed a greater bounty of ideas and opinions and at the same time suffered such a famine of facts. True, we have some good, solid information about the organic endowment of fine-grained rocks, young and old. And we’ve documented in many ways in many places the mode of occurrence of oil and gas in coarse-grained or broken rocks. Thus we feel rather sure of the beginning and the end of the migration scene. Why, then, have we not been able to make factual observations of petroleum in the act of moving from one place to another? Certainly we have tried. We may have to give up the idea of witnessing the movement. But in lieu of direct observation, why can we not interpret the “signs” of movement unequivocally?
Anyone interested in these course notes probably feels as we do that if we knew more surely how oil and gas moved, we could more surely track them to their resting places. But the migration enigma has baffled a lot of honest, hard-working experts. The authors of these notes are recognized for their work in this field. With the hope that it can generate the will among listeners and readers to apply fresh, logical thought to the problem, we have asked them to tell us whatever they can about the physics and chemistry of the migration scene. We cannot expect them to agree with each other on all points of interpretation, but we value highly the factual data they offer to enable us to think or rethink the migration problem objectively.