| 摘要 |
<p>A method and apparatus for determining true formation porosity utilize downhole measurement-while-drilling neutron porosity measurement devices. A initial measurement is taken shortly after the formation is bored and before any substantial invasion by the drilling fluid occurs. Subsequent measurements are made until a steady, no longer increasing, measurement is reached indicating saturation of the formation by the drilling fluid to the depth of the measurements. The difference between the initial and steady measurements is indicative of the true porosity of a gas containing formation.</p> |
