摘要 |
<p>A real-time method is disclosed for maintaining subterranean formation stability through monitoring the interaction between the formation and fluids introduced into (or produced from) a wellbore penetrating the formation. The method employs real-time wellbore (in)stability logging methodology. The method is exemplified by a Pore Pressure Transmission (PPT) test. In such test, test fluids are exposed to Pierre II shales (20 % w/w NaCl solution and sodium silicate fluid with 20 % w/w NaCl, for example) in a PPT apparatus. Membrane efficiency of the two fluids when exposed to the outcrop shale is calculated, and based on the simultaneous acquisition of acoustic data, estimation of a dynamic rock property is made. Calibrating representative shale (or other formation) core response to drilling fluids (or well service fluids, enhanced recovery fluids, or production fluids) under realistic in-situ conditions aids in accurately modeling for time-dependent formation (in)stability in the field for the entire life of the wellbore, from drilling, completion and through production.</p> |