Increase In Exploratory Drilling Research Articles

Developments in Southeastern States in 1956

A total of 270 exploratory tests were drilled in the southeastern states during 1956, compared with 271 for the preceding year. Twenty-one discoveries, consisting of 16 new fields, 1 new pool, and 4 extensions to known fields, were made, resulting in an over-all exploratory success rate of 7.8%. Of special significance was the discovery of the Ansley field, which revealed Lower Cretaceous possibilities in a large, relatively unexplored area of south Mississippi. Geophysical and core-drill exploration registered a 3.5% increase with 2,032 crew-weeks. The seismograph, with 1,723 crew-weeks, continues as the major exploratory tool. Production in Mississippi increased substantially (18.6%), and Alabama production more than doubled. The successful completion of 49 wells in the Citronelle field accounts for the marked increase in Alabama production. As in 1955, Florida production decreased slightly (6.9%). All exploration activity is expected to increase steadily. The extensive leaseholds acquired following the discovery of Lower Cretaceous production in Alabama and Mississippi are still in the process of being evaluated. A pronounced increase in exploratory drilling should follow the evaluation of this acreage.

General Geology and Historical Development, Texas and Oklahoma Panhandles

The Texas Panhandle consists of thirty-two counties bounded on the south by the south lines of Bailey, Lamb, Hale, Floyd, Motley and Cottle counties, and the Oklahoma Panhandle includes Cimarron, Texas and Beaver counties, the three most western counties in the state. Since 1949, when the first pre-Pennsylvanian oil was produced in the panhandles, there has been a gradual increase in exploratory drilling, reaching boom proportions in the significant wildcat campaign of early 1956. Major structural basins include the western Anadarko basin, the connecting Hugoton embayment, and the Dalhart, Palo Duro, Hardeman, and Hollis (Harmon) basins. Some of the more important positive or uplift areas are the buried Amarillo mountains or Amarillo uplift, the Matador archipelago, the Cimarron uplift, Bravo dome, Hall County anticline, Childress anticline, and the Narcisso structure. The first gas produced in the panhandles was found in Potter County, Texas, in December, 1918, and the first commercial oil was found in Carson County, Texas, in May, 1921. These areas and a considerable part of the central Texas Panhandle were later found to form the giant Panhandle field. The Hugoton field was discovered in December, 1922, and several years later it was found to be connected to the Panhandle field. For more than 20 years, until 1943, there were no new discoveries in the Panhandle; then the Keyes field of Cimarron County, Oklahoma, was found. In 1945 and 1946 some oil was found in Lamb, Hale, and Floyd counties, Texas. From 1947 to 1951 there were only a few new discoveries; two of the more important were the Light field (Beaver County, Oklahoma), and the Lips field (Roberts County, Texas). From 1952 until the beginning of 1956 many fields were discovered in the panhandles, most of them are in Beaver and Texas counties, Oklahoma, and in Hansford, Ochiltree, Hutchinson, and Roberts counties, Texas. Several of these fields have multi-pays, and one, the Quinduno field (Roberts County), has rather extensive Wolfcamp Brown production. The stratigraphy of the area includes beds ranging in age from Cambrian to Recent. Underlying the sediments are the rocks of the pre-Cambrian igneous complex. A nearly complete sequence of the Paleozoic rocks is recognized in the subsurface. Most of the newly developed production is in Pennsylvanian rocks, the Morrow sands leading in importance. Only inconsequential pre-Pennsylvanian production is known, but one small area produces oil from the Arbuckle (Ellenburger). The Permian Wolfcamp dolomite and granite wash produce in the Hugoton and Panhandle fields. Mesozoic beds are present in the subsurface of most of the western panhandles, and overlying these rocks are the Llano Estacado (Staked Plains) sediments. The rate of successful new-field wildcats in the panhandles for the past 2 or 3 years is much higher than the national success average of about 11 per cent. The success ratio in an active part of the western Anadarko basin for 1954 and 1955 is slightly below 50 per cent. The over-all success ratio for the entire Panhandle area in the same period is about 25 per cent. Consequently, it appears reasonable to forecast a continued optimistic rate of successful new-field wildcat completions in the Oklahoma and Texas panhandles.

Developments in Montana, North Dakota, and South Dakota in 1953

A slight increase in exploratory drilling characterized 1953. In North Dakota 25.7% of the exploratory tests were successful. Development drilling dominated North Dakota activities. Deep production was developed in both Montana and North Dakota, well removed from previously known structures. South Dakota's first commercial well was on production tests as the year ended. Greatly increased drilling and slightly declining geophysical activity are anticipated in 1954.