1 9-1. The following pressure-production history is available for an oil well. The producing gas-oil ratio is calculated with sales-gas volumes, i.e., stock-tank gas is vented and not measured. The separator operates at 67F and 100 psig; the specific gravity of the separator gas is 0.788, and the gravity of the stock-tank oil is 46.0 API. Estimate the bubble-point pressure and the solution gas-oit ratio at the bubble point for this black oil. Compare your answers with laboratory data which indicate a bubble-point pressure of 1928 psig and a solution gas-oil ratio at the bubble point of 623 scf/STB. Cumulative oil production, Producing gas-oil ratio, sct/STB Reservoir pressure, psia STB 723 493 5,931 518 486 499 111 4,770 483 530 537 530 UTI 11,800 60,800 96,000 145,100 255,800 379,800 465,800 513,600 663,400 816,200 961,000 1,007,000 1,098,300 1,221,000 1,354,200 1,503,600 1,557,500 1,649,900 1,801,800 1,950,000 1,997,600 2,065,700 2,652 491 514 613 753 1,829 848 871 764 1,640 820