The Cross Cut-Blake district is in the extreme northwestern part of Brown County in north-central Texas. The country is one of low relief with low ridges caused by escarpments of the limestones of the Cisco group. The area has an average elevation of 1,575 feet. The producing area comprises isolated pools producing from thin, irregular sands in the lower part of the Canyon series of the Pennsylvanian. The producing sand varies from a depth of 1,100 feet in the eastern part to 1,550 feet in the western part of the area. Unimportant gas production has been discovered in the underlying Bend limestone although any appreciable supply has not been developed. The producing area is one of many located on or near the Bend flexure. The structure, on the producing formation, is of l w magnitude, consisting mainly of noses and closures of small areal extent on the west-dipping Canyon beds. The structure, as reflected on the surface beds of the Cisco series, is less pronounced. Consequently, there is considerable convergence of the beds above the Cross Cut sand and particularly between the Cross Cut sand and the Ranger limestone. Production is controlled by a combination of lenticular sands and structure with the oil and gas being found in the highest parts of the sand lenses, regardless of their structural position. The thickest part of the sand lenses is generally found on the higher parts of the pre-Cross Cut sand topography either because of differential deposition or because of post-Cross Cut sand stream erosion in the topographically low areas. This district has produced more than 6,300,000 barrels of oil through 1940 and almost 95,000 barrels during that year.