The oil-producing districts of Kansas comprise the northern portion of theso-called Mid-Continent field. As shown in the accompanying map, thesedistricts are located chiefly in the southeastern and south central parts ofthe state. A considerable area in southeastern Kansas, extending northwardnearly to Kansas City, has long been known as oil territory, the productivewells being distributed in patches or spots of irregular size and shape, thelocation of which is controlled by conditions of rock structure, and by thetexture and porosity of the ‘sands’ beneath the surface. In south centralKansas, there are a number of producing fields, the location of which appearsto be controlled chiefly by well-defined structure. The most importantdistricts are those in Butler County, especially that in the vicinity of ElDorado, which was for a time the most productive district in the entireMid-Continent field. Recently new production of importance has been brought inthe vicinity of Peabody and present development is active to the north acrossMarion County. Tests in the western parts of Kansas have not been successful infinding new petroleum fields. History The first well drilled for petroleum, in Kansas, was near the town of Paola, Miami Co., about 40 mi. southwest of Kansas City, in the summer of 1860, only afew months after the completion of the famous ?Colonel? Drake discovery well inPennsylvania. Kansas appears to be the second state to engage in a seriousattempt to find oil by drilling. The Civil War caused the temporary abandonmentof attempts at oil development in the state. It was in the vicinity of Paola, where numerous oil seepages had been observed, that the first well producing oil in commercial quantities was drilled, wherealso gas was first piped to the city for commercial use. AIME 065–14