Neutron Log & Density Log
Neutron logs are logs that are used to measure the hydrogen index contained in the rock formation. Hydrogen index is the ratio of the concentration of hydrogen atoms / cm cubic of rock on the content of pure water at 75 F. Neutron log is not really measure the porosity, but measure the hydrogen index in the pores of rocks.
The more porous rock, the more higher the hydrogen content and hydrogen index. Thus, rocks that contain lots of hydrogen can be interpreted to have high porosity as well. In practice the interpretation of porosity can be done with collaboration of neutron log with density log.
Density logging was conducted to measure the density of the rock along the borehole. Density is measured the overall density of the rock matrix and the fluid contained in the pore. The working principle of the tool is the emission of radioactive sources. The more dense rocks the more harder radioactive rays and fewer emissions of radioactive emissions are calculated by the receiver (counter).
Merging neutron porosity log and density porosity log are very useful for detecting gas in the reservoir zone. Gas zones are indicated by 'cross-over' between the neutron and density logs.
In the picture above looks at the reservoir zone (low gamma ray), there is a 'cross-over' between the density and neutron. , in this case the neutron porosity lower than the density porosity.
Keywords: neutron log, density log, density log, well log, log, Neutron Log & Density Log
Reference:
John T. Dewan, "Open-Hole Nuclear Logging - State of the Art" - SPWLA Twenty-Seventh Annual Logging Symposium, June 9-13 1986.
http://ensiklopediseismik.blogspot.com/2009/02/neutron-porosity-dan-density-logging.html
Surjono, S.S., Sarju Winardi., D.H.Amijaya.2010. Analisis Sedimentologi, Pustaka Geo, Yogyakarta
Harsono, Adi. 1994. Pengantar Evaluasi Log. Schlumberger. Jakarta
Neutron logs are logs that are used to measure the hydrogen index contained in the rock formation. Hydrogen index is the ratio of the concentration of hydrogen atoms / cm cubic of rock on the content of pure water at 75 F. Neutron log is not really measure the porosity, but measure the hydrogen index in the pores of rocks.
The more porous rock, the more higher the hydrogen content and hydrogen index. Thus, rocks that contain lots of hydrogen can be interpreted to have high porosity as well. In practice the interpretation of porosity can be done with collaboration of neutron log with density log.
Density logging was conducted to measure the density of the rock along the borehole. Density is measured the overall density of the rock matrix and the fluid contained in the pore. The working principle of the tool is the emission of radioactive sources. The more dense rocks the more harder radioactive rays and fewer emissions of radioactive emissions are calculated by the receiver (counter).
https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgymbiE2dhBsBy_RGZR8rZdtf4as8MJ0CWg-A8w-YyaBKRBHkpMu7Whatpy3uUyfmma5DQyCBF65xemP0Qzkv-VBZdW6nBNyEeZokRYWbKl5sGcU4irAD3MIGQqt_Eu4xsgifrfx8FKPJH3/s400/
In the picture above looks at the reservoir zone (low gamma ray), there is a 'cross-over' between the density and neutron. , in this case the neutron porosity lower than the density porosity.
Keywords: neutron log, density log, density log, well log, log, Neutron Log & Density Log
Reference:
John T. Dewan, "Open-Hole Nuclear Logging - State of the Art" - SPWLA Twenty-Seventh Annual Logging Symposium, June 9-13 1986.
http://ensiklopediseismik.blogspot.com/2009/02/neutron-porosity-dan-density-logging.html
Surjono, S.S., Sarju Winardi., D.H.Amijaya.2010. Analisis Sedimentologi, Pustaka Geo, Yogyakarta
Harsono, Adi. 1994. Pengantar Evaluasi Log. Schlumberger. Jakarta
