A description of the use of palaeontology in oil exploration work in south-west Persia. The nature of the stratigraphy makes the use of micropalaeontology essential and the hardness of the dominantly calcareous rocks necessitates the preparation of thin sections in the field to identify diagnostic microfossils.
Une description Ide l'utilisation de la paléontologie dans les travaux de recherches de pétrole dans le Sud-Ouest de la Perse. Les problèmes posés par la stratigraphie rendent fondamentale l'utilisation de la micropaléontologie et la dureté des roches calcaires prédominantes nécessite la préparation de sections minces sur le terrain pour l'identification des microfossiles. -
During the last three years detailed stratigraphical surveys have been carried out by geologists of the Anglo-Iranian Oil Company in the mountains nearest to the existing oilfields of south-west Persia.
The object of the surveys was to trace the thickness and facies variations of the formations exposed in the Zagros mountain belt and to extrapolate them into the adjoining oilfield belt where the same formations are buried underground. The information gained is used to make forecasts of formation depths and thicknesses, and of various other factors affecting the drilling of oil wells, as well as having a most important bearing on the interpretation of geophysical results. * Anglo-Iranian Oil Company Ltd., Masjid-i-Sulaiman, Persia.
During the course of the surveys several stratigraphical markers were found and traced over great lengths of country. Quite often, minor distinctive lithological units or alternatively signs of erosion, solution-weathering and non-sequence were found to recur again and again in similar positions in the stratigraphical column. For more detailed subdivision, however, especially within a series of uniform lithology, and for correlation from place to place palaeontological work has been found essential.
Close co-operation between the field-workers and the palaeontologists has been maintained throughout the course of the surveys. Some of the results of this co-operative work are described below.
Organisation of the Work The field work for the stratigraphical surveys is carried out by self-contained parties of from two to four geologists with a number of Persian survey workers working under the direction of a party leader.
Each party is away from headquarters for six or seven months, communicating by runner and a chain of supply mules. Motor transport is used for communication in the more accessible areas.
The field work has been carried out by Dr. A.
Allison, Dr. P. E. Kent and Messrs. C. A. E. O'Brien, F. C. Slinger, L. E. T. Parker, J. Law, J. F. Watson and H. R. Warman who continued the survey in sta es from Kabir Kuh through Luristan, Bakhtiari Mr.
