202 I. C. WHITE — THE MANNINGTON OIL FIELD. 



Just where the Mannington licit will end toward the southwest is, as 

 yet, uncertain. Oil has been developed along it to within one mile of 

 the Harrison county line, but in my opinion the belt will end not far 

 from the latter point, since at the farthest well in advance (Blaker num- 

 ber 1) the sand is becoming limy and much split up with slate. 



It is quite probable that in passing westward from this non-productive 

 region clown the dip of the rocks through Harrison, Gilmer and Dodd- 

 ridge counties the sand may improve in quality, and another belt on a 

 different strike may be found, since there is a dip of about 300 to 400 feet 

 before we come down to the bottom of the geological slope and reach the 

 floor of the Appalachian basin* 



The lower group, or Venango oil sand, has not yet produced oil in 

 any of the half dozen wells drilled through these sands along the Mount 

 Morris-Mannington belt, but some gas has been found in Marion and 

 Harrison counties and quite a large flow in Doddridge county; so that 

 there can hardly be any doubt that when the proper search is made in 

 these sands further down the slope of the rocks than in the few trial 

 borings already made, oil will be developed in large quantity, just as 

 certainly as the drill shall rind a good, porous sand reservoir in this 

 series of deposits, since the group of beds making up the Venango series 

 is still present in Monongalia, Marion, Harrison and Doddridge counties, 

 at least, and of about the same thickness and structure as in Washington 

 and Greene counties. Pennsylvania, 



The Origin of Petroleum. 



The geological structure in the Mount Morris-Mannington field is so 

 plainly connected with the accumulation of the oil deposits that consid- 

 erable light is thrown upon the much mooted problem as to the genesis 

 of petroleum. 



The tias is on one side of a long slope of sand, with salt water on the 

 other and the oil between. Did the petroleum in this Mount Morris sand 

 come up from below and simply stop in the sand as a reservoir because it 

 could not escape to the surface, or did it originate in the sand rock itself? 

 The rock is an ancient sea-beach or shallow water deposit, and where 

 exposed at many localities in the country contains marine shells, racoids, 

 and frequently land plants in such quantity as to form thin coal seams, 

 which have even been found by the drill in regions where this rock is 

 barren of oil; so that there was evidently no lack of organic matter in 

 the original deposition of the rock. When the drill descends below this 

 stratum a succession of gray and red shales, with other sand rocks, occurs 



*Siin-,- tli.' reading <>i this paper .-i promising oil well lias been drilled ;it Center Point, Doddridge 

 eouniy, several mil'- west of the Mannington strike line 



