Accounting for geological and geophysical costs;

              Accounting for Geological and Geophysical Costs
BY PRESLEY S. FORD, JR. Partner, Tulsa Office Presented before the American Association of Women Accountants, Tulsa --June 1957
In order that we may intelligently approach the subject of accounting for geological and geophysical costs, let us first define what is meant by the term "geological and geophysical."
In the final analysis, oil is where you find it, and the drilling of a well is the only method by which to prove whether or not oil or gas occur beneath any given portion of the earth's surface. Yet, scientists in the ninety-eight years since the drilling of the Drake well have devised a variety of methods by which to predict the probable occurrence or non­occurrence
of oil or gas and thereby reduce the great financial risks attendant upon the drilling of wells. Among these methods are the following:
1. Geological methods
(1) Location of surface oil or gas seeps — the original method for
the discovery of oil.
(2) Surface geology — the location through the study of surface
outcroppings of rock formations or stratigraphic features which are favorable to the occurrence of oil or gas.
(3) Sub-surface geology--the study of oil-bearing strata as re-
vealed in existing wells with a view to predicting the occur-rence of the same formations and favorable geologic struc-tures in other areas, through the correlation of the record of the rocks as it is revealed in the sedimentary beds laid down in the long course of earth history.
(4) Core drilling — the drilling of relatively shallow wells of small
diameter for the purposes of obtaining core samples of the rock strata occurring beneath the surface in an area where wells have not been drilled and of obtaining information as to the structure of the sub-surface rocks.
2. Geophysical methods
(1) Magnetic survey — the use of a magnetometer to measure vari-ations in the intensity of the earth's magnetic field in an area and, on the basis of these measurements, to map sub-surface structures resulting from the intrusion of igneous rocks which contain magnetic ferrous materials.
55