Abstract: Deep oil reservoir is characteristic of deep buried depth and large thickness, and is hard to drill through the oil formation. To address the issue of oil column height calculation for deep oil reservoirs, we established a heat transfer model of deep reservoir by considering the vertical heat transfer process from the oil-water interface to the wellbore after well production. We solved the model using variable substitution, variable separation and Fourier transform, and then derived the calculation formula of oil column height. By only using the temperature data at the bottom hole before and after well production, we can calculate oil column height. A pilot test was carried out at an oil well of a deep reservoir located at Tarim Basin to demonstrate the calculation process of oil column height. At the same time, by substituting the testing well data into the heat transfer model, we simulated the values of formation temperature and temperature gradient at different location of the oil formation at different production time. Then, we plotted the temperature distribution curve for different production time and the dynamic temperature curve for different formation location. The simulation results showed that formation temperature distribution took on nonlinear dynamic variation characteristics. The established heat transfer model is a good tool to calculate oil column height for deep oil reservoirs.

Key words: deep reservoir, oil column height, heat transfer model, temperature distribution, temperature gradient