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RATE project
Helium diffusion experiments givenuclear evidence for a young world
“1.5 billion years” of nuclear decayoccurred between4,000 and 8,000 years ago
Updated !
D. Russell Humphreys, Ph.D.Institute for Creation Research
Tiny “zircon” crystals in the Earth’scontinental crust are radioactive
Zirconium Silicate, ZrSiO4
75µm
Contain Uraniumand Thorium atoms
The radioactivity makes helium
Eighthelium
atoms
Nuclear decay in zircon
U-238
Pb-206
The helium is still in the zircons
Fenton Hill, New MexicoLos Alamos geothermal site
Radioisotope age: “1.5 Billion years”
Helium retained in Zircons% of “1.5 Billion” year’s worth:
0.127739305
1.223935024
1719729003
2715121702
581059601
Helium(%)
Temp.(ºC)
Depth (meters)
Sample
The helium diffuses out of the zircons
HeliumAtom
Lightweight Fast-movingSlippery
Crystal Atoms
Wiggles through crystalLeaks through cracks around crystals
The hotter the crystal, the faster the diffusion
Pure Crystal
Defects
Temperature (°Kelvin)33340050066610002000Infinity
Inverse Temperature, 1000 / T0 0.5 1 1.5 2 3
Diff
usio
n R
ate
Hot Cold
2.5
Typical “Arrhenius” plot:Diffusion ratevs. temperature
We needed ratedata for zircon
Before 2001, only one measurement of helium diffusion in zircon was in printMagomedov (1970)“Study of the mechanism of radiogenic productmigration in zircon”,Geokhimiya 2:263-267.
Magomedov’s data were ambiguousWhat does
mean?
Interpreting “ln D” makes a big difference
lneD
lne(D/a2)
log10D
1.0 1.2 1.4 1.6 1.8 2.0
10–14
10–12
10–10
10– 8
10– 6
10– 4
1000 / Temperature (ºK)
D(c
m2 /s
ec)
In 2000 we assumed this— very fast diffusion
Russian zircon interpretations
Zircons are embedded in biotite, a dark mica
Biotite
Zirc
on
Biotite might slow down diffusionHelium-in-biotite rateshad not been measured
So in 2000 we commissioned experiments on biotite
We developed two theoretical models
Predicted biotite rates required to retain observed helium for:
1. 6000 years (Creation)
2. 1.5 Billion years (Uniformitarian)
Zircon
Biotite
We published the predictions in the year 2000
In 2001 we found zircon was more important
1.0 1.2 1.4 1.6 1.8 2.0
10–14
10–12
10–10
10– 8
10– 6
10– 4
lneD
lne(D/a2)
log10D
1000 / Temperature (ºK)
D(c
m2 /s
ec)
2001 zircon data agreedwith lowest Magomedovinterpretation
2001 Nevada Zircons
So we started zircon experimentsand changed models to zircon
Russian zircon interpretations
Biotite data 10 x aboveCreation model
10 -23
10 -21
10 -19
10 -17
10 -15
10 -13
10 -11
1.2 1.4 1.6 1.8 2 2.2 2.4 2.6
2001 Nevada1970 Russian
re-interpreted
UniformitarianModel
CreationModel
D(c
m2 /s
ec)
1000 / Temperature (°K)
Zircon creation model within 0.5% of biotite
Defect line
Still needed Jemezzircon measurements 100,000 x
difference
Published zircon data approached creation model
We extracted minerals from core samplesCore samples fromsame borehole & depths
Crushed, sieved, separated
Fenton Hill site GT2Jemez Granodiorite750 meters & 1500 metersLos Alamos National Laboratory
ICR Geology Laboratory, andActivation Laboratories, Ontario
Extracted zircons were like Gentry’s
An expert measured the helium diffusion rates
Didn’t know sponsors, goals, or sites
10 -23
10 -21
10 -19
10 -17
10 -15
10 -13
10 -11
1.5 2 2.5
2002 Data2003 Data
Uniformitarian
Jemez Zircon Data
July, 2003Lengths 50-75 µmLower temperatures
Creation Model
D(c
m2 /s
ec)
1000 / Temperature (°K)
Shown in ICC paper
Model
New !
Our new zircon data strongly support creation
New data give a more accurate diffusion age
0.1
1.2
17
27
58
Helium(%)
7.97 × 10-16
1.87 × 10-16
5.49 × 10-17
1.09 × 10-17
_____
Measured D(cm2/s)
7330
5730
2400
7270
Age(years)
277
239
197
151
105
Temp.(ºC)
5
4
3
2
1
Sample
Estimated Age: 5680 ± 2000 years
10 -23
10 -21
10 -19
10 -17
10 -15
10 -13
10 -11
1.5 2 2.5 3 3.5 4
Cooler formation? Would require refrigeration!Loophole # 1
– 36°C+105°C
Data extrapolationUniformi-tarian
Model
D(c
m2 /s
ec)
1000 / Temperature (°K)
Model extrapolation
141°C
249°C+277°C
1.5 Gyr requires:> 140°C cooler most of the time
To– 100°C
Loophole # 2
Much helium outside zircons? Data say “no”
BiotiteZirc
on
zircon: 1320 nmol / ccbiotite: 7 nmol / cc
Czircon >> Cbiotite
Helium at 1490 meters:
Diffusion always fromgreater to lesser C
4He diffusingout of zircons
Loophole # 3
Big Gentry error? Our data support his
~ 80957502002
2715121702
0.127739305
1.223935024
1719729003
4212414922003
581059601
Helium(%)
Temp.(ºC)
Depth (meters)
Sample
30
40
50
60
100 110 120 130 140 150 160
Helium Retention%
Temperature (°C)
Our 2003 Data1
2
Loophole # 4
“Closure” temperature? Low and not relevantC
losu
re
Ope
ning
Tclosure
Tem
pera
ture
Hel
ium
Time
Time
ClosureInterval << 1.5 Gyr
10 -17
10 -16
10 -15
1.8 2 2.2 2.4 2.6
Jemez zirconclosure temps
128°C
-170°C197°C
105°C
277°C
D(c
m2 /s
ec)
1000 / T (°K)
Two zircon “clocks” disagree by millionsSummary
Nuclear decay:1.5 billion years
Helium diffusion:4000 to 8,000 years
We suggest nuclear decay rate change in past
Conclusion
RATE helium diffusion experimentssupport the young world of Scripture
5680 years± 2000 years