different porosity reading on the neutron porosity log for the same formation due to gas in the pore space.
由于孔隙空间存在着气体,同一地层的中子孔隙度测井和密度孔隙度读数不同。
but it will fail to recognize the gas bearing bed buried deeper by the two methods as its porosity log feature is not obvious, especially when density porosity is lower than neutron porosity.