Radon and radon-thoron ratios can help indicate distance of
glacial transport of radioactive material.|
Airborne and ground gamma-ray and gamma-ray spectrometer surveys find "boulder trains",
trains of radioactive material transported "down-ice" from bedrock sources.
Boulders are commonly transported further than finer material. Also, as transport distance
increases, finer material is mixed with
other non-radioactive fine material. The radioactivity is diluted and not easily detected.
High values of radon and
radon-thoron ratios are due to radioactivity in fine grained material
High gamma-ray values are more likely due to larger chunks and boulders (distant).
Just west of the
Midwest Lake deposit
boulders of radioactive pegmatite are exposed on the
top of an esker. These boulders give an airborne gamma-ray anomaly that is unrelated to the
Midwest deposit and far down ice from the bedrock source.
The real boulder train, which led to the discovery,
is immediately south, "down-ice" of the Midwest deposit.
The radioactive boulders here are angular, friable and weathered, and visual
inspection reveals that they have not travelled far.
This valuable boulder train contains sufficient fine-grained radioactive material to give a
strong radon anomaly, reinforcing the conclusion that the bedrock source was not far "up-ice".
When examining these glacial dispersion trains by
soil geochemistry, we expect that, at least
in the case of organic soils, radium would give a better indication of nearby uranium
mineralization than would uranium.
Radon in soil gas would, in turn, reflect the radium content of the soil.
We measure: radon - radium - thoron - radon daughters - alpha radiation.
is recognized as the most sensitive and reliable method for these elements.
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.
In the radon business since 1968, our latest major instrument update was 2015.
Modern, low-power, field-rugged electronics. Some earlier versions still working after 35 years.
Continuous real-time monitoring and data recording.
Winter and summer, from the Sahara Desert to the Canadian Shield, our instruments have faced up to severe field conditions.
- Intrinsically safe functions.
Sensitive to geochemical trace levels necessary for radon in lake water and for radon-thoron isotope ratios.
Can work in a tent without electricity or be carried from point to point in the field.
50 readings per day. Results available immediately.
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.
Same instruments used for radon and radium in soil, sediment,
plant parts, rocks, water, soil gas, air, and snow, and for radon daughters in air.
- EPA compliant.
Click here for more details of instruments.
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accessories we provide
Technical specification sheets and pictures of our instruments provided on request.
Multilingual consulting and training (if required).
For instruments contact|
R.H. Morse & Associates Ltd.
Robert H. Morse, Ph.D., P.Eng.
January 27, 2010