THE GEOLOGY OF THE OIL REGIONS OF WARREN, VENANGO, CLARION, AND BUTLER COUNTIES. 1880 by John Franklin Carll, 2006 Reprint by Oil Region Alliance. John Franklin Carll (1828-1904) engaged in oil production in NW Pennsylvania for nearly ten years, becoming a recognized local expert on the geological characteristics of reservoirs as well as the engineering practices used to exploit them. When the Second Pennsylvania Geological Survey was organized in 1874, Carll was assigned to the oil region as the first geologist ever employed full-time to specialize in petroleum studies; and he conducted the first systematic scientific study of the oil fields. This book describes the facts and principles regarding the origin, location, abundance, and character of the petroleum deposits in the oil regions of Warren, Venango, Clarion, and Butler counties, as well as the history and mode of their exploitation. Descriptions of oil well rig and tools are given; and preglacial and postglacial drainage of the Lake Erie country is discussed. It also includes surveys of the Garland and Panama conglomerates in Warren and Crawford counties in Pennsylvania, and in Chautauqua County, New York. Contained are two indexes, 23 pages of plates; and an atlas of 22 sheets of maps, well-sections, and working drawings of well rig and tools. 486 pages, 6 x 9 hardbound with dustcover.