Formation gas pore pressure evaluation on drilling cuttings samples

摘要

We disclose an apparatus and process for measuring the Formation Gas Pore Pressure in drilling cuttings samples in the test tube. The Apparatus consist of vertical holder for test tube, for placing the cutting sample and pipette for adding measurable quantity of liquid. (Note: “vertical holder for test tube and test tube” are disclosed in U.S. patent application Ser. No. 10/711,435 Horizontal Binocular Microscope for vertically gravitated and floating samples). The process consist in measuring the gas bubbles size and volume in the test tube and the height of liquid covering the bubble. This we can calculate the volume and the pressure of the gas emitted out of the pores. By adding/subtracting more liquid to the sample and increasing/decreasing the height and the pressure of the liquid on the pore the test is repeated and the measurements documented in the tables for math processing to obtain the error corrections and standard deviation of the measurements. The results are expressed in Emission=V/P=mm3/Pa, Total Volume=V=mm3, Maximum Pressure=P=Pa.