MOUNT ST HELENS REVEALS
FATAL RADIOACTIVE-DATING FLAW
three times larger, Krakatoa in 1883 was 18 times bigger, and
Tambora in 1815 was 80 times larger. The volume of lava
in the Deccan Traps in India is some 5 million times more.
These indicate that volcanic eruptions during Noah’s Flood
were millions of times larger. When we consider the true
immensity of the biblical cataclysm, and how it impacted the
whole earth, Mount St Helens helps us envisage how Noah’s
Flood explains the geology of the world, and how it happened
Once we realize that the Bible is not mythological but
records true events in history, we can approach its message
with a new mindset. Then we are open to make new discoveries about our world and our place in it.
References and notes
1. Morris, J., and Austin, S.A., Footprints in the Ash: The explosive
story of Mount St Helens, Master Books, Green Forest, AR, pp. 50–55,
2003. See also: Walker, T., Geologic catastrophe and the young earth,
Creation 32( 2): 28–31, 2010; creation.com/geologist-steve-austin.
heterogeneous sand mixtures, J. Creation 8(1): 3–50, 1994.
3. Oard, M.J. Ancient Ice Ages or Gigantic Submarine Landslides,
Creation Research Society Monograph 6, Chino Valley, Arizona, 1997.
Creation 21( 2): 18–21, 1999; creation.com/yellowstone.
B. Sc. (Hons.) [geology],
Dr Walker worked in power station design and operation, and the geological
assessment of coal deposits. He works full-time researching and speaking for
Creation Ministries International (Australia). For more: creation.com/walker.
The May 1980 explosion blew 400 m (1,300 ft) from the top of the
mountain, leaving a gaping, horseshoe-shaped crater. The eruption
continued through the year, but by October the volcano had settled
such that lava extruding from inside the mountain could collect in
the crater (figure 11 ). By 1986 it had formed a dome 350 m (1,100 ft)
high and up to 1,060 m ( 3,500 ft) in diameter. With a view to testing
the accuracy of radioactive dating, geologist Steve Austin collected
a sample of the new volcanic rock (called dacite) in 1992.1
All dating methods are based on assumptions because we can only
measure the chemicals in the sample in the present. It is not possible
to go back in time to measure what was in the sample when it formed,
or to know what may have happened to the sample after that. The
eruption of Mount St Helens provided a unique opportunity to test
the dating methods because we know the actual time that the new
lava dome formed.
After preparing a collection of different sub-samples, Dr Austin sent
these to a reputable commercial laboratory to make measurements
suitable for the potassium-argon method of ‘dating’. Some subsamples
were prepared of the whole rock while others were selected to
emphasize different minerals making up the rock. The ‘ages’ of some
of the different sub-samples based on the potassium-argon method,
applying standard dating assumptions, are shown in the table.
Potassium-argon ‘age’ of volcanic rock from Mount St Helens
The calculated ages of the rock from the lava dome ranged from
350,000 years to 2,800,000 years, yet the rock had formed just 10
years before. Clearly the ‘age’ was vastly wrong. A key assumption
of the potassium-argon method is that all argon escapes from the
lava while it is still molten. In that case the ‘age’ would represent
the time when the lava crystallized and the rock became gas-tight.
But that assumption was wrong. The rock already contained lots of
argon when it solidified and so it gave incorrect ‘dates’.
Some people have objected that the tests were inappropriate
because the potassium-argon method only works on rocks that are
millions of years old. 2 However, the plus-and-minus range (±) against
each result cancels that objection. This range indicates the precision
of the laboratory measurement, and in every case the error range
is much smaller than the calculated ‘age’. This shows that the argon
measured was well within the precision of the equipment.
This rare opportunity to test radioactive dating on rocks of
known age has demonstrated that the basic assumptions are not
valid. Volcanic rock produced from this volcanic eruption already
contained so-called ‘daughter’ isotope not produced by radioactive
decay since the rock solidified. The tests have demonstrated that
we cannot trust radioactive dating results on rocks of unknown age.
References and Notes
1. Austin, S. A., Excess argon within mineral concentrates from the new dacite lava dome
at Mount St Helens volcano, J.Creation 10( 3):335–343, 1996; creation.com/lavadome.
2. Countering the critics: Radio-dating in rubble, Creation 23( 3): 24–25, 2001;
11. New lava dome in 1984 building up since the 1980
Sample Calculated ‘age’ – years
Whole rock 350,000 ± 50,000
Concentrate mostly hornblende 900,000 ± 200,000
Concentrate mostly pyroxene 2,800,000 ± 600,000
CREATION.com 27 Creation 39( 3) 2017