Founded in 1982  GrayStone Exploration Labs has a data base of more than 365,000
soil samples analyzed for iodine and other components. Most are for oil and gas
geochemical exploration surveys but also include surveys for uranium and gold.
Samples have been analyzed from Europe, Asia, Australia, North and South America,
and a number of islands.
Frequently Asked Questions
General Geochemical Questions
1) What is Surface Geochemistry? The detection of hydrocarbons, at the surface, which have
leaked from underlying deposits.
3)  Do hydrocarbon deposits really leak? Yes, most of them. Although seismic dominates
exploration now, prior to the 1930's, most oil was found by tracking oil seeps, Tracking invisible
micro seepage  using analytical chemistry is a natural extension of this very successful
exploration method.
4) Does this only apply to shallow deposits? No, I have detected a strong surface signature
for an oil deposit at more than 10,000 feet, and other researches have reported successful
detection of leakage from even deeper sources.
2) Can I use geochemistry everywhere? No, some environments are to extreme to use some
Iodine Questions
1) What does iodine have to do with hydrocarbons? Many different elements become
involved in the oxidation processes surrounding the leaking hydrocarbons. Iodine is a very
reactive element and has a tremendous affinity for organic compounds. Iodo-organic
compounds accumulate In areas of seepage. See
2) Is iodine as good as other geochemical methods I have heard about? I believe it is
better, iodine is one of the best and most versatile geochemical exploration tools.
3) Does rain wash it away? No, the compounds produced by the combination of the
hydrocarbons and iodine are insoluble.
4) Does road salt cause a problem? No, iodine is added to table salt to prevent goiter as
natural rock salt contains almost no iodine.
5) Why do you sample the surface, wouldn't soil a few inches or feet down be
No, soil is a very complex system and the only place in the soil profile that you
can be certain of is the very top of the A horizon. Arbitrary sampling depths measure a
variety of unknowable subsurface conditions. Also the surface allows the integration of
multiple sample locations for each measurement.
Exploration Philosophy
1) Why don't you offer hydrocarbon methods? I have never been convinced that
hydrocarbon techniques are as good as iodine and other soil modification techniques.
Hydrocarbons are volatile, reactive and difficult to contain and measure. The retention, flux
rate and complex chemistry of hydrocarbons in soils have barely been investigated much
less quantified.
2) How many samples should I take? The simplest answer is; as many as you can.
Sample density is the most important factor for successful geochemistry. Think of samples
as pixels in a picture, the more pixels the better the picture. This analogy also
demonstrates that the quality of each pixel, or in this case the number of sample
measurements or sophistication of the analysis, does almost nothing to resolve the larger
picture. This is why my use of a low cost technique spread over a large number of
samples has been more  successful than the more complex and expensive geochemical
techniques using fewer samples.
Much of the data base is from North America and the United States. Our goal is to
provide the best data possible and to continuously improve the quality and value of
our surveys.
Geochemical Exploration Services
GrayStone Exploration Labs, Inc.
GrayStone Exploration Labs, Inc.