Formation pressure and mobility measurements play a critical role in the development and management of compartmentalized reservoirs. Conventionally, wireline formation tester (WFT) tool has been used for such appliations. However, reservoir evaluation becomes challenging in high temperature environment, due to the unchangeable temperature limitations of WFT tools.
This paper presents a case study where formation pressure and mobility are acquired by applying formation pressure testing while drilling (FPWD) at a high temperature (HT) offshore gas well in South Sea, China. With a thermal gradient of as high as 4.5 degC/100m, the estimated formation temperature is higher than the maximum temperature rating of the wireline tools. By integrating detailed pre-job design maintaining the working temperature at acceptable range and real-time monitoring including data quality control and measurement optimization ensuring the functionality of hardware and the quality of measurement, FPWD has successfully revealed the formation properties.