The age of the earth, Part III
Radiometric dating
I) Many dating methods
1) There have and are many dating techniques that have been tried in order to give the
age of the Earth.
2) In fact, at latest count, there are over 70 different techniques that have been proposed
at one time or another.
3) Over half of the techniques show an age for the earth of less than 1 million years.
4) Yet, we never hear of these in the classroom or in debates.
5) There are only 7 which give ages in the billions of years. These are the accepted
techniques since they defend the idea of evolution.
6) They are as follows
A) Samarium - Neodymium. (Sm-Nd)
B) Rhenium - Osmium (Re-Os)
C) Uranium / Thorium - Lead. (U/Th-Pb)
D) Rubidium - Strontium (Rb-Sr)
E) Potassium - Argon dating (K-Ar)
F) Argon - Argon (Ar-Ar)
G) Lutetium - Hafnium (Lu-Hf)
7) It is the radioactive decay of uranium and similar elements that yield an age for the
Earth in billions of years and it is the one method that has been enthusiastically
promoted by Darwinists and uniformitarian geologists, while all other methods
have been neglected.
II) All methods of measuring the age of the earth are subject to defects
1) All methods of measuring time, whether for domestic or scientific purposes, rely on
the same basic principle; monitoring the rate of some constant natural process.
2) Today, our most sophisticated chronometric methods involve the rate at which a
quartz crystal vibrates when an electric potential is applied to it, and the rate at which
radioactive elements decay (said to be the most constant of all).
3) But having some readily available process to measure is not enough by itself. To
measure elapsed time accurately we MUST;
A) Be sure that the process does in fact remain constant, even when we are not
watching.
B) We MUST know the starting value of the clock.
C) We MUST be sure that some external factor cannot interfere with the process
while it is in operation.
4) All these conditions apply to measuring time today. When it comes to the science of
geochronometry, the process we choose will have started in prehistoric times, which
we have no method of directly observing and verifying. This means we MUST make
sure as far as possible that our three conditions (listed above) were met in the past
as well as in the present. This is where the problems begin.
5) On such example would be the increasing salinity of the oceans as proposed by the
Irish geologists John Joly in 1898. On the face of it this is a promising method, since
it can be assumed that initially the oceans consisted of fresh water, and the present-day
accumulation of salt is due to erosion of land masses by rain fall and the subsequent
transport of dissolved salt into the seas by way of the world’s rivers. Even more
encouraging is the fact that the rate of erosion of the land by rainfall is surprisingly
constant each year (about 540 millions tons of salt a year). All that would be
necessary is to measure the present-day concentration of salt is the sea (32 grams
per liter); calculate from this the total amount in all the oceans (about 5x10 to the 16th
power tons); and divide this total by the annual amount of salt deposited to get the age
of the earth.
6) Using this method, Joly came up with an age of 100 million years. Unfortunately,
when we apply the 3 conditions mentioned above to this method, its shortcomings
quickly become obvious.
A) We cannot be sure that the annual runoff of dissolved salt has always been
constant. There is good reason to suppose that climatic conditions have been
very different in the past (with ice ages and major droughts) which might
have had an effect that is not calculable.
B) We cannot be quite sure that there was 0 salt in the sea to begin with. Initially,
salt might have been present, though no one can say how much.
C) It turns out that an apparently constant process is interfered with by external
factors. Large amount of salt are recirculated into the atmosphere, and recent
evidence suggests that the salt in the sea might actually be in a steady state.
7) All methods of measuring the age of the earth are subject, to some extent, to the same
defects, quite simply, no one was there at the time to check up on our 3 criteria.
III) Radioactive methods used
1) The technique covers a family of methods involving the radioactive decay of a number
of different metallic elements with very long half-lives.
2) These include uranium and its sister element thorium, which both decay in helium
and lead; rubidium, which decays into strontium, and potassium, which decays into
argon and calcium.
3) Uranium and thorium methods
A) The basic principle is this; over very long periods of time uranium
spontaneously decays into lead and helium gas. The rate of decay is
remarkably constant. The atoms of the uranium are unstable and
periodically throw off an alpha particle, which is the nucleus of an
atom of helium.
B) The important part of the theory is that the kind of lead into which uranium
eventually decays is chemically distinctive from common lead already
present in the rocks, and is referred to as radiogenic lead, a daughter
product of the decay process. Common lead is an isotope called lead 204,
while the decay product of uranium 238 is lead 206. In order to date a
rock deposit, a sample is taken and the amount of radioactive uranium,
together with the amount of radiogenic lead it contains, is measured in the
laboratory. Since the rate of decay is known from modern measurements,
it is possible to calculate directly how long the uranium has been decaying,
or how old the deposit is.
C) The half-life of uranium 238 has been calculated to be 4,500 million years.
To take a simplistic example, if the assay showed that a deposit was composed
of half uranium 238 and half its daughter product lead 206, then one would
draw the conclusion that the deposit was 4,500 million years old.
D) It would seem on the face of it that the uranium method seems to be the ideal
method and above scientific suspicion. Yet research in recent decades has
begun to cast serious doubts on its reliability.
E) The first criterion of any dating method is that we must know the starting
value of the process we are measuring; we must have a starting point or
reference point from which to make our calculations.
1) Uranium decay seems to fill this requirement since the type of lead
which results from the decay process is said to be uniquely formed as
a by-product of the process.
2) If radiogenic lead (lead 206 and lead 207 from uranium, and lead 208
from thorium) really is uniquely formed as the end product of decay,
then it is perfectly reasonable to suppose that there was no radiogenic
lead in the rocks when they first formed. So, it would seem that we
have a reliable starting point.
F) However, some have suggested that there is another way in which lead 206,
207, and 208 could be formed separate from the decay process.
1) This process is sometimes called “trammutation”
2) Transmutation can occur through the capture of free neutrons (atomic
particles with enough energy to transmute common lead into so-called
radiogenic lead.
3) The source of these free neutrons is in the radioactive ore deposit such
as uranium, where they occur through spontaneous fission.
4) As well as decaying into radiogenic lead, it is also making available a
supply of particles which are spontaneously converting common lead
into another isotope which, on being assayed, will be indistinguishable
from a radiogenic product of alpha decay.
5) This mechanism would tip the measurement in favor of an old earth.
To much radiogenic lead would lead us to imagine that the process
has been going on for much longer that it actually has.
6) In the neutron capture process, the isotopic values of lead would be
systematically changed; lead 206 would be converted into lead 207,
lead 207 would be converted into lead 208 which constituted more than
half the lead present in any given deposit. This is normally interpreted
as meaning that thorium, the parent element of lead 208, was very
common in the deposit in question, yet it also can be interpreted as
resulting from the free neutron capture process.
7) This process has been documented. In two of the world’s largest
uranium ore deposits, one in Zaire and the other in Canada, the
measurements that were taken have shown that while there was
practically no thorium 232 in the ore, they do contain a significant
amount of lead 208. This could only be derived from lead 207 by
neutron capture which turned it into lead 208.
G) But the method also fails the second criterion-that we must be reasonably
sure no outside agency can interfere with the smooth running process.
1) Uranium does not naturally occur in metallic form but as uranium
oxide.
2) This material is highly soluble in water and is known to be moved
away from its original deposit in large quantities by ground waters.
3) The type of effect this has on dating is unpredictable since some parts
of a mineral deposit can be unnaturally enriched while others are
unnaturally depleted.
H) There is one further discovery relating to the uranium dating method. It has
to do with the other daughter product of the decay process. Helium.
1) If the uranium to lead dating technique is reliable, then the amount
of radiogenic helium in the atmosphere would yield a date for the
earth’s age consonant with that yielded by measuring the amount
of radiogenic lead in the crust. Yet, the dates are so different as to be
irreconcilable.
2) If the earth were 4,600 million years old, then there would be roughly
10,000 billion tons of radiogenic helium 4 in the atmosphere. Actually,
there are only around 3.5 billion tons present.
3) Uniformitarian geologists have attempted to explain this by assuming
that the other 99.96 percent has escaped from the earth’s gravitational
field into space, yet this process has never been observed.
4) In fact, more recent studies have suggested that fat from losing helium,
the atmosphere may actually be gaining quantities of this gas.
5) As the earth orbits the sun, it does not move through empty space but
through a thin solar atmosphere, which consists principally of
hydrogen and helium resulting from the nuclear processes within the
sun.
6) Measurements in the upper atmosphere have suggested that the earth is
gaining helium by this means.
7) If we take the measured amount of helium 4 in the atmosphere and
apply the radioactive dating technique to it, we find that the calculation
yields an age for the earth of around 175,000 years.
8) This method fails our criteria of reliability in that the possible
acquisition of helium 4 from outside upsets the process.
4) Potassium and rubidium methods
A) Potassium minerals are commonly found in many rocks. Potassium 40
decays by capturing an electron and turning it into the gas argon 40, with
a half-life of 1.3 billion years.
B) Advocate of this method claim that the argon gas that results remains trapped
in the crystal structures of the mineral in which it forms and accumulates
through the ages, thus acting as a clock when the stored daughter isotope
is released and measured.
C) This method is suspect because argon 40 is a very common isotope in the
atmosphere and the rocks of the earth’s crust. In fact it is the 12th most
abundant chemical element on earth and more than 99% of it is argon 40.
D) There is no way to tell whether any given sample of argon 40 is the residue
of radioactive decay or was present in the rocks when they were formed.
E) Moreover, as argon is an inert gas that will not react with any other element,
its atoms will always be trapped in the crystal structures of minerals no matter
if it is the radiogenic kind or naturally occurring.
F) It has been calculated that even if the earth were 5 billion years old, no more
than 1% of the argon 40 currently present on the earth could be a radiogenic
daughter product and it is thus highly probable that some of the argon 40 in all
potassium minerals has been derived directly rather than as a result of decay.
G) The possibility of anomalous inclusion of argon is not merely conjecture but
is borne out by numerous studies of volcanic rocks that have resulted in false
dates.
1) The radiogenic argon and helium contents of three basalts erupted
into the deep ocean from an active volcano (Kilauea) have been
measured. Ages calculated from these measurements increase with
sample depth up to 22 million years for lavas deduced to be present.
(Hawaiian Institute of Geophysics)
2) Hawaiian basaltic lave actually dating from an eruption in 2801, near
Hualalei, came up with potassium-argon dates ranging from 160
million years to 3 billion years.
3) In 1969, McDougall of the Australian National University measured the
ages of lave in New Zealand and got as age of 465,000 years whereas
the carbon dating of wood included in the lave showed it to be less
than 1,000 years old.
H) Dating advocates accept that the potassium-argon methods can be flawed but
claim that they know the occasions on which the results are correct and when
they are not. Like all radiometric methods, the potassium-argon method does
not work on all rocks and minerals under all geologic conditions. By many
experiments over the past 3 decades, geologists have learned which rocks
and minerals act as closed systems and under what geological conditions
they do so.
1) The problem with this belief is that there is no truly independent
means of verifying the age of any given sample.
2) The experiments consist solely of rejecting dates that seem wrong
while accepting those that seem right. “Seem” in this context means
in line with uniformitarian expectations, thus compiling a database
of self-fulfilling predictions.
I) Radiogenic strontium-strontium 87- occurs in rocks as a result of the decay of
radioactive rubidium. However, this method is complicated by the fact that
strontium 87 also occurs both as a daughter product and as a commonly
Occurring element. Typically, rocks contain 10 times more common
strontium 87 than radiogenic strontium 87. It is also suspect because it is
subject to exactly the same neutron capture as uranium- lead. This time
strontium 86 can be turned into strontium 87.
IV) Why discordant ages are accepted
1) Most disconcerting of all is the fact that these various methods of dating commonly
produce discordant ages for the same rock deposit.
2) Where this occurs, a “harmonization” is carried out, in other words, the figures are
adjusted until the seem right.
3) The chief tool employed to harmonize discordant dates is the simple device of labeling
unexpected ages as anomalous and, in the future, discarding those rock samples that
will lead to the anomalous dates. This practice is the explanation of why many
dating results seem to support each other, because all samples that give ages other
than expected values are rejected as being unsuitable for dating.
4) If radioactive dating is seriously flawed why is it so enthusiastically embraced. There
are 4 ways in which scientists could mislead themselves, ways that may be
transparent to them, and which could lead them to obtain comparable results
apparently independently.
A) The untestable error.
1) When errors in radiometric dates are pointed out by critics,
advocates of the method usually dismiss such criticisms on the grounds
that errors are very rare in comparison with the thousands of dates
that are not found to be incorrect.
2) This is a misleading argument because the overwhelming majority
of dates can never be challenged or found to be flawed since there
is no genuinely independent evidence that can contradict the dates.
3) The reason why known anomalies are very rare is simply because
independent evidence is very rare.
B) The phenomenon of “ballpark thinking”
1) This is exemplified by the error that was made in the curvature of the
mirror of the Hubble space telescope. The error was not discovered
by normal inspection processes, even in one of the world’s best-
equipped labs, because it was so big, more that a centimeter out, that
it was outside the range that6 anyone was mentally prepared to check
on. Had it been a millionth of a meter out, it would have been spotted
at once.
2) Ever since Lyell estimated that the end of the Cretaceous was 80
million years ago, the accepted value has been in this ballpark.
Any dating scientist who suggested looking outside the ballpark, at 20
or 10 or 5 million years, would be looked on as a crackpot.
C) The phenomenon of “intellectual phase-locking”
1) It is not widely realized that the published value of physical constants
often varies. Before is was settled internationally by definition, the
Measured value for the velocity of light varied considerably.
2) One reason for such variation is that all scientists make experimental
errors that they have to correct.
3) They naturally prefer to correct them in the direction of the currently
accepted value thus giving an unconscious trend to measured values.
4) This group thinking has been given the name
“Intellectual phase- locking”.
D) Powerful pressures to conform to the consensus.
1) Dating geologists are offended by the suggestion that their belief can or
would influence the dates obtained. Yet nothing could be easier or
more natural.
2) Take for example a rock sample from the Cretaceous period, which is
universally accepted to date from some 65 million years ago. Any
dating scientist who obtained a date from the sample of 10 million
or 150 million years ago would not publish such a result because
they will, quite sincerely, assume it was in error.
3) On the other hand, any dating scientist who did obtain a date of 65
million years age would hasten to publish it as widely possible.
4) Thus the published dating figures always conform to preconceived
dates and never contradict those dates.
5) If all the rejected dates were retrieved from the waste basket and added
to the published dates, the combined results would show that the
dates produced are the scatter that one would expect by chance alone.
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