Problem 3: For a sandstone reservoir, calculate the water saturation if the porosity (Ø) is (20 %), the resistivity of the formation water (Rw) is (0.09) and the true resistivity (R.) is (15)? Problem...

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Extracted text: Problem 3: For a sandstone reservoir, calculate the water saturation if the porosity (Ø) is (20 %), the resistivity of the formation water (Rw) is (0.09) and the true resistivity (R.) is (15)? Problem 4: Calculate the water saturation for a sandstone reservoir if the porosity (Ø) is (10 %), resistivity of formation water is (Rw = 0.02 Om) and the resistivity of the formation (Rt= 20 Qm)?