At the beginning of my career, petroleum engineers tended to be physicists with a strict observance of physical principles and a deep belief in the power of mathematics. Something that couldn't be calculated or measured to a few decimals behind the comma should be considered to be a dubious property, better left alone.
Geologists at this time tended to take the opposite view – virtually nothing was measured and most geological processes were poorly understood and rarely underbuilt by solid physical theories. Statements were vague and full of jargon, alien to the engineer’s ear.
Mining engineers form a hybrid group situated between physicists and geologists. Their work always involves problems related to geological features which are not fully understood and for which there is no representative data base – thus there is need for estimating ranges of parameter values and for the determination the significance of the inherent uncertainty levels toward the economics of a project ...
Safety margins should not be carried too far, as was shown by the bridges on Sumatra built by Delft mining engineers before the war. When these had to be blown up to retard the Japanese advance, this proved to be almost impossible. This example also demonstrates the reluctance of the mining engineer to believe in the outcome of theoretical calculations, being used as they are to the unpredictable surprises prepared by nature.
Thus, the world of the mining engineer is one of calculated risk. One must be inventive, pragmatic and sufficiently courageous to reach the necessary operational decisions at the right time.
This doesn’t guarantee a glorious career, because in my experience high positions often go to people who systematically avoid having to make any significant decision. However, it will certainly result in a very satisfactory working life.
While in Iran I made long trips on the weekends to study archeological sites and do some clandestine digging.
One day coming down from the mountains I noticed the faint outline of streets in the valley, marked by slight variations of vegetation highlighted by the low sun. Digging in the corner of a buried house wall I discovered pottery fragments – and underneath a silver drachme of Alexander the Great.
You will understand that I have the fondest memories of these weekends in the wild, almost deserted mountains, seeing bears, wolves and mountain sheep. I still have a little carpet from the Qasgai nomads, whose camp I visited. I noted innumerable caves that still beg to be excavated. What a wonderful place to work in!
(In describing his work on the North Sea’s Leman gas field, near the Norfolk coast, where the reservoir is the Rotliegendes Sandstone Formation – and a corresponding trip to America.)
Luckily, I already had seen an ideal analog for the Leman Rotliegendes in northern Arizona, in the Canyon de Chelly. There one finds an Aeolian Permian sandstone with the same thickness and the same cross-bed set types as in the Leman field.
A short field trip was planned to measure the necessary data. Arriving at the Chelly Canyon National Park I found the hotel permanently booked by tourist groups.
A kind Navajo girl in the park entrance lodge referred me to the mission post run by a Methodist vicar and his family. This was a journey back in time. These marvelous people, straight from a western movie, lent me their schoolroom plus a camp bed for the duration of my stay, and I was in business.
I already had planned a tight schedule of sketching and photographing a series of cliff faces pre-selected on the basis of detailed maps and photographs in the splendid magazine Arizona Highways. Sketching from the edge of the cliffs in this fantastic landscape I gradually detected more and more Indian ruins of the famous cliff dwellers.
Sitting still for hours on end, the animals became curious. Squirrels sat next to me and the vultures spiraled in ever-tightening circles.
In the evening I worked out my drawings with the aid of Polaroid camera photographs. On Ascension Day a large party of Indians arrived for an all-night service. Sitting quietly behind my table, accompanied by a few hungry mice, I was suddenly struck by a soft, mumbling sound. Looking around I saw a series of round spots on the fogged windows. Immediately there came a knocking on the door and a string of little Indians filed in – the way to the toilet was via my room, but, of course, the real reason for their activities was formed by the stack of peppermints and chocolates piled on the table. They were a very polite, delightful bunch of rosy-cheeked children, thickly bundled against the cold of a May evening on a Colorado plateau. When my goodies were finished the trips to the toilet dwindled fast.
The use of the outcrop data was based on a typical soft science type consideration. Having made a model of the large-scale festoon cross-bedding of the Rotliegendes based on small German outcrops, I was struck by the resemblance to fluvial trough cross-bedding. Because that type of cross-bedding shows a clear relationship between thickness, length and width, I reasoned that the same might be true for the Aeolian cross-bed sets. Even when the full length or width of a cross-bed set is not exposed, this still allows for making an estimate of the width/thickness and the length/thickness rations by measuring exposed lateral continuity, bed thickness and lateral terminations of a bed.
Through a normalizing process one can add up all information and derive average values…
I would like to refrain from making comments or of suggesting all kinds of great ideas for the future. I think it is a bad habit for departing people to try to influence the coming generation…
Production geology is not a discipline in which Nobel prizes are likely to be awarded. It is characterized by a continuous confrontation with new challenges and the gradual development of improved understanding and methods. As such it is a most interesting, satisfying and adventurous lifetime occupation.
This is certainly the case for me, and I find myself lucky to have a profession that is also my hobby.
Editor's Note: In his own words: Excerpts from “Adventures in Soft Science,” by Koenraad Weber. Weber’s talk, “Production Geology, Tangent Plane Between Geologist and Engineer,” was presented Dec. 1, 1999, at Delft University of Technology.