Radon in Air
in Exploration Drill Holes

  • We present data by A.B. Tanner from an orientation survey near Grants, New Mexico.
  • The figure shows a radon profile obtained from air samples drawn from drill holes in the lower part of the ore zone.
  • The profile is 1300 feet long, and crosses an orebody 100 feet wide within a mineralized area 160 feet wide.
  • The radon anomaly shown on the figure is much wider than indications shown by U3O8 analyses.
  • Uranium analyses of cuttings and core give information on a column of rock the diameter of the drill hole. Gamma logs increase the effective sampling diameter to about two feet. In many cases, however, radon will migrate much farther than this and provide information from a much wider area.
  • Samples can be collected from old drill holes and seismic shot holes as well as new exploration holes. Simply lower a tygon tube, pump air into the instrument, and count the sample at the site. Readings can be taken at various depths by raising or lowering the tube. Holes with anomalous radon are followed up by stepouts; holes with background values abandoned.
  • We measure: radon - radium - thoron - radon daughters - alpha radiation.
  • The Lucas cell is recognized as the most sensitive and reliable method for these elements.
  • Intrinsically safe functions.
  • Sensitive to geochemical trace levels necessary for radon in lake water and for radon-thoron isotope ratios.
  • immune to beta and gamma radiation.
  • one monitor works with a number of (less expensive) detectors.
  • Our instruments are used around the world in exploration for uranium, oil & gas, groundwater and hydrothermal, and in environmental protection, health physics, earthquake prediction, and evaluation of hydrocarbon and NAPL contamination etc.
  • Same instruments used for radon and radium in soil, sediment, plant parts, rocks, water, soil gas, air, snow, food, and for radon and thoron daughters in air.
  • Winter and summer, from the Sahara Desert to the Canadian Shield, our instruments have faced up to severe field conditions.
  • In the radon business since 1968, our instruments are updated regularly with the most recent major re-design in 2015. Modern, low-power, field-rugged electronics. Some earlier versions still working after 40 years.
  • Continuous real-time monitoring and data recording.
  • RS232 port/pc software.
  • User programmable measurement intervals, sample and count periods and alarm level settings.
  • Can work in a tent without electricity or be carried from point to point in the field.
  • 50 readings per day. Results available immediately.
  • Portable. Rechargeable battery pack good for a long day in the field and recharges in a few hours.
  • Can be operated by junior personnel if carefully supervised.
  • EPA and CE Mark compliant.
  • Click here (www.finderschoice.com/rn) for more details of our radon instruments, and for other instruments, components and accessories we provide.
  • Technical specification sheets and pictures of our instruments provided on request.
  • Multilingual consulting and training (if required).
For instruments contact

Robert H. Morse, Ph.D., P.Eng.
May 9, 2007
Radon in Drill Holes
Showing Wide Radon Anomaly

Radon in Air in Drill Holes Showing Wide Radon Anomaly

Tanner calculated that, under certain conditions, determination of radon in air in drill holes could reduce the cost of drilling by a factor of 16.

From A.B. Tanner, Increasing the efficiency of exploration drilling by measurement of radon in drill holes: Proceedings of the 2nd U.N. International Conference on Peaceful Uses of Atomic Energy, 1958, vol.3 pp.42-45

Click here for technical details and other applications of our radon instruments.

Copyright 1968 - 2018, R.H. Morse & Associates Ltd., all rights reserved.