METHOD AND APPARATUS FOR FAST PORE PRESSURE MEASUREMENT DURING DRILLING OPERATIONS

摘要

A method and apparatus for measuring the pressure of a formation penetrated by a wellbore is provided. A downhole tool is positioned in the wellbore and a probe is extended therefrom into sealing engagement with the formation. A piston in the probe is retracted therein where by a cavity is defined for receiving a fluid from the formation. A pressure underbalance in the cavity draws fluid from the formation into the cavity. An oscillator may be used to fluctuate the flow of fluid into the cavity. A pressure gauge is used to measure the pressure of fluid in the cavity.