A serious need of the petroleum industry is standardization of the definitions and classification of exploratory wells, for only upon a generally accepted nomenclature can satisfactory estimates be made of the exploratory effort in the search for new oil and gas reserves. After much discussion and correspondence, we have prepared a statement of definitions and a classification of exploratory holes which, we hope, will prove to be suitable for general use. This topic is treated in Part II of the present report, where numerous explanatory comments are included.

In Part III is our review of exploratory drilling in 1943. This year we are following the proposed classification (Part II) in referring to "exploratory holes," a term which, however, is analogous to the word "wildcats," as used in our earlier reports on this subject. On this basis, in 1943, 3,843 exploratory holes were drilled as contrasted with 3,212 holes drilled in 1942. The total exploratory footage drilled in 1943 was 15,122,364 feet as against 12,123,994 feet in 1942. The average depth of hole increased from 3,775 feet in 1942 to 3,935 feet in 1943, for all states covered; and from 4,647 feet to 4,968 feet in the southern states. Again, we have compiled figures on exploratory drilling and on estimated proved reserves in the eleven states of Arkansas, California, Illinois, India a, Kansas, Louisiana, Michigan, Mississippi, New Mexico, Oklahoma, and Texas.

From all points of view, as brought out by these statistics, the exploratory effort must be still further stepped up during 1944.