... reservoir definition, or new wells with hole conditions that prevent open-hole logging. The PND-S™ system is commonly used in place of open-hole logs on development wells. The development and application of pulsed-neutron porosity measurements in cased wellbores are discussed in refs. 1 through 5...

... analysis of sand-shale sequences in western Canada, Texas gulf coast, and Montana. Applications (in combination with the cased-hole neutron porosity) include providing porosities where hole conditions make open-hole logging unviable, and in old wells where no modern porosity logs exist or the data...