Identification of Downhole Fluid Properties Using Wireline Formation Test Data

In the process of offshore exploration, wireline formation sampling technology is an important means to identify the properties of reservoir fluid. However, due to the invasion of drilling fluid, reservoir permeability, pumping efficiency and other factors, the cable formation test operation often cannot obtain relatively pure undisturbed formation fluid samples, resulting in the difficulty of judging the properties of reservoir fluid. In this paper, three methods are compared and analyzed. One is the pressure gradient method based on the difference of oil and water density to distinguish fluid properties; Secondly, formate is used as the characteristic ion to calculate the purity of the sample and judge the fluid properties of the sample; Third, the fluid acoustic time difference parameter can directly reflect the properties of the current pumped fluid. The formation pressure analysis data can effectively identify the fluid properties of the reservoir and divide the oil-water interface, which improves the efficiency of exploration and development. Formate is used as a characteristic ion to calculate the purity of cable formation test samples, which expands the original calculation method and is compared with the traditional method. The effect is good and increases the reliability of on-site water analysis technology. The acoustic time difference method changes the idea of conventional sampling, making the sampling operation more purposeful and efficient.