Questions 10. A rock of unknown brine saturation was used in a flooding experiment where brine resistivity was measured at 15.cm. The rock has a 1.2 in diameter and a 6.5 in length, with a porosity of 9.4%. A resistance of 23286 was measured across the rock. The following equations describe the system: F=0.822;Ir=Sw1.8. Calculate the brine saturation in the rock. 11. A cylindrical core has a 2 in diameter, 3.5 in length, and a porosity of 17.8\%. Using retort distillation, 15.3cm3 of water and 12.4cm3 of oil were extracted from the core. If the formation factor of this rock is given by F=1.242.1, the resistivity index is given by Ir=Sw1.9, and the water resistivity is 9.4.cm, calculate the true resistivity of the core which we would expected to have before fluid extraction. Questions 12. A cylindrical core, of 2.5cm in diameter and 5cm in length, has a porosity of 22%. The retort distillation method was used in order to find the fluid saturation inside the core. Using this method, 3.2cm3 of water and 2.0cm3 of oil were extracted from the core. - a) What are the fluid saturations in the core? - b) If the formation factor is given by F=1.092, the resistivity index is given by Ir=Sw2, and the water resistivity is 7.5.cm, calculate the true resistivity of the core which we would expect to have it measured before fluid extraction