In this paper surface and subsurface maps of an area comprising six townships and four producing fields are shown. From these and other data it is concluded that these producing folds are anticlinal buried hills and are contemporaneous with the Nemaha Mountains. Surface geology was largely responsible for the development of this area. The subsurface folds directly underlie the surface folds with remarkable consistency.
The conclusion is drawn that the surface folds are due to differential settling and depositional dip of the upper horizons over the Ordovician buried hills. The principal producing horizon is the unconformable contact between the Ordovician and later sedi-ments. Furthermore, it is concluded that the oil has migrated laterally for some distance from its source in the lower Pennsylvanian and Chattanooga shales to its present position.
Figures & Tables
Modern petroleum geology in the United States had its beginning in the first decade of the 20th Century when the U.S. Geological Survey began mapping the structure of the rocks in and near old fields in order to discover the various types of structural conditions under which oil and gas are trapped. Structural geology has evolved as a branch of the broader science far more rapidly than have methods of mapping the attitude of rocks at the surface. This volume, published in the late 1920s, was designed to afford authoritative and modern descriptions of the structure of typical oil fields in the United States. Each of the 30 fields contained here is described by an author who is intimately familiar with the available data. The relationship of structure at the surface and at depth for different terranes is clearly set forth wherever the strata are not parallel. Fields include: McKittrick, California; Fairport, Kansas; Urania, Louisiana; Artesia, New Mexico; Burbank, Oklahoma; Cabin Creek, West Virginia; and Luling, Texas.