31. In the early 1900s, big companies began to plumb the Caddo-Pine Island oil reservoir around Vivian, Caldwell said. 32. The operating company may also inject water or gas into the oil reservoir in order to increase oil recovery. 33. Light said a witness from another team saw two pressurized canisters in the oil reservoir , one that had exploded. 34. General conclusions can not be drawn because the physical and mineralogical characteristics of the oil reservoirs reported were different. 35. Drillers continued to find new oil reservoirs throughout the 20th century, with new discoveries still occurring in the 1980s. 36. The thin red circular contour line in the middle of the map indicates the top of the oil reservoir . 37. Nansen Saleri, Saudi Aramco's oil reservoir manager, claimed the company's estimates are actually more conservative than these guidelines allow. 38. The strike caused petroleum production to fall dramatically and damaged the country's huge oil reservoirs , according to industry experts. 39. This drive frame reciprocates vertically which then drives the double acting independent oil pumps located in the oil reservoir . 40. About a half dozen other school sites are also being checked for gas that seeps up from underground oil reservoirs .
