Within the last three years Archer County, Texas, has risen from a position of relative unimportance as a producing area to one of the principal productive districts in the Mid-Continent field. At the present time there are 34 producing areas varying in size from pools of one or two wells to fields covering as much as 1,200 acres. Practically all of the production is confined to sand zones in the lower part of the Cisco group (Pennsylvanian) which are regionally persistent but locally very erratic. Development and operating costs are low, the oil is of high gravity (39-42 Baume), and the wells are relatively long-lived.

The paper discusses the origin and accumulation of the oil as well as problems of porosity, ultimate yield, etc., of this particular district. Various tables show pertinent facts regarding individual fields and the relationship of surface to subsurface structure. Cross-sections show stratigraphic relationship of the fields and of the county to adjoining areas.