Definition - What does Nuclear Log mean?
A Nuclear Log is a log used to measure various interactions between the formations and the radiations emitted from the logging tools. The spectrum gamma logs are used to measure the radiations that occur naturally. The nuclear logging process has been in use since late 1920s to gather information on rock characteristics and lithology. The aim of using log analysis is to determine the downhole values of various reservoir characteristics mainly permeability, porosity and fluid saturation. A Nuclear Log measures only the neutron count or gamma ray rates at the detectors.
Petropedia explains Nuclear Log
Nuclear Log interpretation includes the smart processing of the tool readings. For better log analysis, it is essential to understand what these tools really measure. To measure radioactivity, the photons or particles are converted to electronic pulses that can be sorted and counted as function of their energy. The detection of radiation depends on ionization which is indirectly or directly produced in a medium through which the radiations pass. To carry out nuclear logging, three types of detectors are used – Geiger-Mueller tubes, proportional counters and scintillation crystals. The statistical nature of the radioactive decay is considered when interpreting or running the nuclear logs.