Neutron Probes: The Pros and Cons

A device that measures the quantity of H20 in localised areas of soil, a Neutron Probe is used widely across a range of fields. Especially in wire line logging, the probe provides vital information that helps detect the amount of hydrogen that is present within the earth and in turn, help make decisions about the prospects of the area. The probe contains a pellet of americium and beryllium which makes the detection possible when the alpha particles from the americium collide with the nuclei of beryllium. 

Carrying both advantages and disadvantages, here are some of the pros and cons surrounding the Neutron Probe.


  • Despite the physical state of the soil itself, moisture can still be detected. 
  • Not only can the probe detect the current state of the soil, it can log changes across time to give a wide overview of the area. 
  • With a very sensitive capture, the probe can record rapid moisture changes.
  • With the ability to record large amounts of soil, the probe is great for accurate measurements which is simply not the case for other probes. 
  • It’s incredibly efficient and can record accurate measurements regardless of the depth. 


  • It can be difficult to measure if the moisture measurement depends on physical and chemical properties. 
  • Due to probes containing radioactive sources, using the equipment requires a certain level of care and expertise. 
  • Because the soil surface does not reach within the neuron probes sphere of influence, there may be an inaccurate result as the immediate moisture cannot be measured. 

Looking at the pros and cons, it is important to weigh up your requirements before proceeding with a specific probe. It is possible to see that although the Neutron Probe is very useful in some situations, it may fall in others and so consulting with an expert in logging is essential.