Analysis of Boron Effects on Wireline Estimates of Porosity and Gas Saturation in Tight Gas Sands. Topical Report, November 1989-December 1991.

摘要

Two primary properties derived from formation evaluation in tight gas zones are porosity and gas saturation. Porosity and gas saturation may be determined by thermal neutron porosity logs and pulsed neutron logs in existing wells. New wells may use other methods such as resistivity, nuclear magnetic resonance and electromagnetic logs in combination with other logs such as density, epithermal neutron, sonic and chemical elemental analysis logs. In the complex pore systems that typify a vast majority of tight gas sand resources, the interpretation of these logs is extremely complicated. The primary focus of the study is to provide empirical correlations of boron with other logs so that the boron effect on the thermal neutron porosity and the pulsed neutron water saturation on existing wells may be compensated for in tight gas sands in the Travis Peak, and Cotton Valley formations of Texas and the Frontier formation of Wyoming. These correlations will result in better estimates of porosity and gas saturation in tight gas sands. These techniques for boron correction have not previously been used.