Originally Broadcast April 5, 1997 |
Last Revised Jan 27, 2001 |
INFINITY #7: Age Dating Before History.
by Daniel H. Harris, Ph.D.
I. The Questions.
How can a scientist measure the age of a bone, or a rock? Should such an age measures be trusted? Is there good reason to believe that the Earth is millions
and millions of years old? This
INFINITY will answer these important questions.
II. How Old Is That Bone In the Ground?
Imagine you are a scientist and someone asks you to find the age of a
very old bone which has not yet turned from bone into stone. The bone doesn't come with a label
giving its age! So what can you do? One thing a scientist can do, is to
measure the amount of radioactive carbon 14 in the bone. So how does a carbon 14 measurement tell us the bone's age? To see how, read on.
III. The Basics of Carbon 14 Dating.
To understand carbon 14 [C14] dating, [also called the radiocarbon
method] we must understand where radioactive carbon 14 [C14] comes from, how C14
decays, how it gets into the bodies of plants and animals, and how C14 measures
give us an estimated age. We begin
with the process that makes C14.
A.
Making Radioactive Carbon 14.
Scientists know that today high energy particles called cosmic rays are
slamming into the top of the Earth's atmosphere.
Cosmic rays collide with atoms in the atmosphere creating showers of
energetic sub-atomic particles, which continue downward into the atmosphere. Some of these energetic shower particles
are neutrons. When these energetic
neutrons strike the nucleus of an ordinary nitrogen atom, high in the
atmosphere, the result is the formation of a radioactive C14 atom.
[An element is designated according to the number of protons in its
nucleus, 1= hydrogen, 2=helium, 3=lithium, 4=beryllium, 5=boron, 6=carbon,
7=nitrogen, 8=oxygen, 9=fluorine, 10=neon, etc.]
[An ordinary nitrogen nucleus has 7 protons and 7 neutrons. When a cosmic ray neutron combines with
an ordinary nitrogen nucleus, the temporary result is a nitrogen nucleus with 7
protons and 8 neutrons, and excess energy.
Without delay, the nitrogen nucleus ejects a proton, which takes away
most of the excess energy. What
remains then is a carbon nucleus with 6 protons and 8 neutrons. This is radioactive C14.]
B.
The Decay of Radioactive Carbon 14.
Each radioactive C14 atom is unstable because its nucleus has excess
energy. To get rid of that excess
energy the C14 nucleus ejects a high energy electron, and the result is a stable
nucleus of ordinary nitrogen. [see C. below]
This process of the C14 nucleus splitting apart is called radioactivity,
or radioactive decay, which is why C14 is said to be radioactive. [The electron takes away the excess
energy of 0.156 Mev.]
On average it takes about 5,730 yrs for half of the C14 atoms to decay,
so 5730 years is said to be the half life of C14.
A very few C14 nuclei decay right away, others take longer, some atoms
wait much more than 5,730 yrs before they decay. But on average half of the C14 atoms are gone in about 5,730
years. After another 5,730 years
half of the remaining C14 atoms have decayed; leaving only 1/4 of the original
C14 atoms; and so forth.
C.
Some Easily Neglected Details of C14 Decay.
[Each C14 atom has 6 protons and 8 neutrons in its nucleus, thus a total
atomic mass number of 14, which is why it is called C14. The most common isotope of carbon is
C12, which has a nucleus made up of 6 protons and 6 neutrons. The C12 isotope is also the most stable
form of carbon. The two extra
neutrons in C14 are what makes the C14 isotope is unstable. To reach stability the nucleus ejects an
electron [one negative charge] which carries away the excess energy. By this means the nucleus, which begins
with 6 positive electric charges, looses a negative charge, giving the nucleus 7
positive charges. The nucleus then
has 7 protons and 7 neutrons, which is the common stable form of nitrogen.]
[The half life of C14, which is the amount of time needed for half of the
C14 atoms to decay, is variously listed in different sources. Willard Libby reported a half life of 5568 years, others
reported values being, 5680 years, 5745 hears and 5730 years. The value now commonly used is 5730 years. These half lives are reported on page 5,
C.M. Lederer et. al., "Table of Isotopes," Sixth Ed., John Wiley &
Sons, N.Y.]
D.
How Carbon 14 Gets Into Plants and Animals.
When radioactive C14 is formed high in the atmosphere (mostly about 10-15
km. high) the C14 rapidly combines with oxygen to make a radioactive form of
carbon dioxide, CO2. Already
present in the atmosphere is the more abundant non-radioactive CO2,
containing nonradioactive C12. When
the radioactive form of CO2 is formed, it rapidly mixes with the more
abundant nonradioactive CO2, and the mixture is transported
throughout the atmosphere. [The
mixing - circulation time in the atmosphere is so short compared to the 5730
year half life of C14, that the C14/C12 ratio shouldn't vary by more than about
1% throughout the atmosphere, so scientists treat the C14/C12 ratio is the same
throughout the atmosphere.]
Nearly all carbon in the atmosphere is part of carbon dioxide gas, so CO2
gas contains small amounts of radioactive C14, with about one C14 for every
trillion ordinary C12 atoms.
The CO2, with C14, is taken out of the air by plants in the
process of photosynthesis, and the C14 is incorporated into plant tissues. The plants containing the C14, are then eaten by animals. That is how the radioactive C14 gets
into an animal's body.
E.
How C14 Measures Give an Estimate of Age.
As long as the animal lives it continues eating and absorbing carbon,
including radioactive C14. But the
body is also loosing carbon, as cells die and tissues are recycled by the body. There is a constant turnover of carbon
in the body. Carbon is leaving the
body with very very slightly decayed C14, and at the same time fresh carbon is
entering the body with a C14/C12 ratio the same as the bulk of the atmosphere. Since the carbon recycling time in the
body is very short compared to the 5730 year half life of C14, the body will
have, as long as it lives, a C14/C12 ratio essentially the same as the
atmosphere. Thus scientists suppose
that the carbon which is part of the animal's body at the time of death has the
same fractional C14/C12 ratio as does the atmosphere at the time of death.
When the animal dies the recycling of carbon in the body stops. No C14 goes into the animal's body,
because dead animals don't eat, and the C14 atoms that are already in the body
continue vanishing by radioactive decay. The
C14 in the animal's body continues vanishing while the ordinary, nonradioactive
C12, is unaffected. Over time the
animal's body looses its C14, and then the remaining carbon is all
nonradioactive C12.
Again remember that about half of the C14 atoms present split apart in
the first 5730 years. After another
5,730 years half of the remaining C14 atoms have decayed; leaving only 1/4 of
the original C14 atoms; and so forth.
So by measuring the present C14/C12 ratio in the bone, and comparing that
C14/C12 ratio to the C14/C12 ratio in the atmosphere when the animal died, a
scientist can estimate the how long ago the animal died.
F.
Some Necessary Assumptions.
When we consider how C14 dating works, it becomes clear that there are
three assumptions built into the dating process.
For example, we must, 1) assume that we know exactly how much C14
was in the bone when the animal died; and 2) we must assume that while
the bone was buried, that no C14 was either added to the bone, or removed from
the bone; and 3) we must assume that the decay rate of radioactive C14
has been constant in the past. Then,
if and only if we making these assumptions, we can use the present C14/C12 ratio
in the bone to give an estimate of the age of the bone.
IV. Some Problems With C14 Dating.
If we wanted to test the assumptions built into the C14 dating method, we
would have to go back in time, and take measurements on the bone, and
measurements of the C14 decay rate, etc. But
we can't go back in time, and therefore we can't test the assumptions built into
the C14 dating method.
So, if we want to use the C14 dating method we must make assumptions. Because
these assumptions are built into the dating method, and because these assumptions
are not testable, the resulting age estimate is not empirical science. The resulting age is an uncertain
estimate. But that's not all, there
are other problems with the C14 dating method.
A.
The Amount of C14 in the Bone at Death.
Because no scientist examined the animal's bones when it died, we must
somehow estimate the C14/C12 ratio in the animal's bones when it died [we must
know the starting conditions]. To
do this scientists assume that when the animal died, the C14/C12 ratio in
the Earth's atmosphere was then the same as it is today. [That is, scientists assume that the
C14/C12 ratio in the Earth's atmosphere has been constant during at least the
last 100,000 years.]
Scientists assume that on average there is a balance between the
amount of new C14 being made each second by cosmic rays, and the amount of
existing C14, which decays each second in the entire atmosphere. And they assume that the
formation and decay processes have been balanced and unchanging for at least
100,000 years.
[For this to be true; 1) the cosmic ray intensity must be unchanging with
time; 2) the Earth's magnetic field, which acts as a partial shield of cosmic
rays, must also be unchanging; and 3) the volume and temperature of the oceans,
which can absorb or release large amounts of CO2, must also be
unchanging. Such constancy seems
unlikely for a variety of reasons. For
an in depth discussion see p58-61 of "The Illustrated Origins Answer
Book" Fourth Ed. by Paul S. Taylor, Eden Publications, Mesa Ariz. 1992]
B.
But the C14 Abundance in the Atmosphere is Changing!
One thing we can do is to measure the actual rate of C14 production, and
the C14 decay rate, in today's atmosphere.
Actual measurements and calculations of the production and decay rates
show that the assumed balance between the production rate and the decay rate
of C14 does not exist [see Ref 1]. The present rate of C14 production in the
atmosphere [given by Willard Libby (1955) as 18.8 atoms/gram/minute] is perhaps
20% greater than the rate of C14 decay [given by Libby (1955) as 16
atoms/gram/minute]. So the
amount of C14 in the atmosphere is increasing.
Since the amount of C14 in the atmosphere is presently increasing, we
would expect to find that ancient samples of organic material of known age,
likely started out with less C14 to begin with.
And that is exactly what we find. Studies
of bones and wood known to be some 5000 yrs old, show that there was very little
C14 in Earth's atmosphere some 5000 years ago.
An animal that died then, with a reduced amount of C14 in its bones at
death, would start out with less C14 to begin with, and so when dated by the C14
method, would seem to be very old, even on the day it was buried.
Ref. 1, see p317-320, Ian T. Taylor, "In the Minds of Men: Darwin
and the New World Order," Third Ed., TFE Publishing, Toronto, 1991.
C.
Some C14 Measures Which Raise Doubts.
When the C14 dating method is used on living mollusks, like snails, their
shells seem to be as much as 2,300 years old.
It seems that mollusks, including snails, have a way of keeping C14 out
of their shells. Wood from some
living trees have given C14 dates up to 10,000 years. And freshly killed seals have been C14
dated at 1,300 years, while 30 year old seal carcasses have been dated at 4,600
years. These observations call into
question the usefulness of all C14 dates. [For further details see p58-61, of
"The Illustrated Origins Answer Book" Fourth Ed. by Paul S. Taylor,
Eden Publications, Mesa Ariz. 1992]
V. Other Radiometric Dating Methods.
Radiocarbon dating is only one of many dating methods which depend on the
radioactive decay of substances. When
radioactive decay is used for estimating the age of an bone, or a clam shell, or
a rock, the method is called radiometric dating.
Some of the more commonly used radiometric methods for dating rocks
include the Potassium-Argon method, the Rubidium-Strontium method and the
Uranium-Lead method. In these
example the first element named is the parent element, which decays into the
second named element, called the daughter element, or daughter product. So in the Uranium-Lead method, Uranium
by radioactivity over time turns into Lead.
In all such radiometric dating methods the resulting date is an estimate
of the date when the rock solidified, when it went from molten to crystallized
material. So these methods can only
be applied to volcanic rocks.
[Sedimentary rock is formed when rocks and/or organic materials [like the
shells of mollusks] are broken into small pieces by moving water and later
deposited, as the sediment settles out of moving water. Because the breaking of a rock or shell
into pieces doesn't change its chemical makeup, the radioactivity processes
inside the material are unaffected. Likewise,
when tiny pieces of sediment are deposited to make a rock, there is no change in
the chemistry of the rock, and no effect on the radioactivity processes inside
the rock. Therefore, the erosion
and deposition dates of sedimentary rocks can't found by radiometric methods.]
VI. Uniformitarian Dating Defined.
Dating events in the distant past, by using an ongoing process, such as
radiometric dating, is called uniformitarian dating. The ongoing process is viewed as if it
is a clock running down. These
dating methods are called "uniformitarian," because they rest on the
assumption that the process rate has been uniform and unchanging, even in the
distant past.
VII. Understanding the Limitations of Dating Methods.
To better understand the uncertainties and difficulties involved in
uniformitarian dating methods, lets look at a simple example. You arrive at a friend's remote cabin,
and find a kerosene lantern burning. Immediately
you think, how long has the lamp been burning.
To answer that question, you must know how much fuel was in the lamp when
it was lit. You could assume
that the lamp was full, but maybe it wasn't.
You must also measure the present burning rate, and assume that
the burning rate did not change before you arrived. And you must assume that no
unknown events affected the burning process, or the amount of kerosene.
If all your assumptions are justified, then the burning lamp can be
treated as a clock that gives an accurate time.
But if any one of your assumptions is wrong, then your estimate of the
burning time will be wrong, and you won't know it, because you believed your
assumptions.
VIII. The Unavoidable Assumptions Present in Dating
Methods.
So
any uniformitarian dating method rests on assumptions:
1) You must assume the starting conditions.
2) You must assume a constant process rate. And
3) You must assume that nothing unexpected happened.
In our example, someone could have added or removed kerosene from the
lamp after it was lit. Or someone
could have adjusted the lamp, making it burn faster or slower before you
arrived. They could have even
turned the lamp on and off several times over a period of time.
Every uniformitarian dating process depends upon the same three
unavoidable assumptions. These
assumptions could only be tested if we had perfect knowledge of the past. In that case we wouldn't need to make
assumptions, and we wouldn't need to use uniformitarian dating methods. But we can't go into the past to check,
so if we use a uniformitarian dating method, we must make these three
unavoidable assumptions
IX. No Dating Method is Empirical Science.
True science, empirical science deals with the here and now, what we can
test in a laboratory, what can be verified in many laboratories. But we can't examine the past in any
laboratory, its beyond our reach, just like the distant stars. No one knows what happened in the
distant past when there was no one watching. Since we can't directly examine the past, and there are
untestable assumptions built into all uniformitarian dating, uniformitarian
dating is not empirical science.
Every uniformitarian dating method attempts to estimate an age based upon
uncertain assumptions. Because the
assumptions are, by their very nature untestable, and their validity is
unknowable; every age estimate given by a uniformitarian dating method is in
reality just an educated guess.
X. Some Known Problems With Radiometric Dating Methods.
Each of our three unavoidable assumptions can be questioned for a variety
of reasons.
A.
The Starting Condition Must Be Known.
As we have seen with C14, it is often difficult to estimate the amount of
radioactive parent substance present at the start of a decay process. But some assumption(s) must be made
about the starting conditions. In
general the assumed starting composition rests on an uncertain theoretical model
of the original chemistry of an ancient material.
[In some cases the assumption(s) rest on uncertain theoretical studies of
processes which supposedly make chemical elements in stars.]
B.
The Process Rate Must Be Constant.
It is well known among nuclear physics experimenters that bombarding
particles, and other external influences, can affect nuclear decay processes,
and nuclear decay rates. An extreme
example can be seen in a nuclear reactor or an atomic bomb, where bombardment by
neutrons greatly speeds up the natural radioactivity of uranium. Bombardment by high energy light waves
called gamma rays can also affect nuclear decay processes. [Bombardment by neutrinos can also
affect decay rates.]
One should also consider that measures of radioactivity decay rates have
only been made since about 1920. That
is some 80 years. If decay rates
were variable with external influences, or some as yet unrecognized slow
process, then 80 years is such a very short time, such decay rate variations
might not be noticed. Consider, for
instance, the decay half life of uranium, which is measured to be 4.5 billion
years, that is a factor of 56,000,000 times farther back into time than we have
measurements. That is quite an
extension beyond the realm of our measures.
Is it therefore reasonable to assume that radioactivity has always
happened in the past, in exactly the same way as it does today, when we must go
beyond our measurements by a factor as great as 56,000,000? I think not.
C.
There Must Be No Unknown Changes in the Sample.
If we look at a buried bone, or rocks, it is well known that ground water
can flow through buried bones and rocks and either add, or remove radioactive
chemicals, altering the estimated radiometric date. In some methods the daughter element is
a gas, as it is in the Potassium-Argon method.
The movement of Argon into and out of rocks is now an important
uncertainty in the controversy regarding this radiometric method.
It should also be noted that in general a radiometric date can be
affected by either adding to or removing the parent element, and by either
adding to or removing the daughter element.
Thus we have four possible ways that a radiometric date can be affected.
XI. More Problems With Radiometric Dating.
To illustrate, the reality of radiometric dating, lets look at the
example of some actual radiometric dates of volcanic rocks at the Grand Canyon.
Lava flows of volcanic basalts on the rim of the Grand Canyon, have
flowed down into the canyon. Samples
from these volcanic basalts, give widely differing radiometric ages. A variety of Rubidium-Strontium radiometric methods give
dates near 1.3 billion years for these rocks.
Basalt rocks buried deep at the bottom of the Grand Canyon, which should
be much older than those on the rim and poured into the canyon, give ages of
only 1.0 billion years. So the
Rubidium-Strontium methods used tells us that the younger lava flows at the top
of the Grand Canyon, are older than the rocks at the bottom of the canyon. [These measures are reported p58-60 of
J.D. Morris, "The Young Earth, Master Books, Green Forest AR, 1996. Greater details may be found in Chapter
6 of Steven A. Austin, "Grand Canyon Monument to Catastrophe, Institute for
Creation Research, Santee, CA, 1994.]
Numerous dating discrepancies of this kind call into question the
validity of the assumptions necessary in all radiometric methods.
XII. The Way Scientists Treat Dating Results.
When scientists use radiometric methods, they often split a rock or bone
up into several samples, which are then sent to different laboratories, where
the samples are dated by a variety of radiometric methods. In general the radiometric dates
reported by the laboratories to the investigator disagree, sometimes quite
dramatically.
If, for example, three different laboratories give three different dates
for the same rock or bone, how does the scientist decide what to believe? Most scientists who face this situation
pick a date that seems reasonable, on the basis of their existing prejudices,
and throw away the others, perhaps not even reporting them.
It is allegedly common practice among investigators:
1) to
report in the main text of a research paper, review paper, or textbook, those
findings which nearly agree with expectations;
2) to
place those findings in a footnote which only modestly disagrees with
expectation; and
3) to
not mention at all those findings that substantially disagrees with the
scientist's or reviewer's expectations.
The unacceptable dates are disregarded or discarded assuming some error
of method, or that the samples were modified of contaminated. So published ages depend as much upon the prejudices and
expectations of the writers as they do upon the dating method itself.
XIII. Why Scientists Rely on Radiometric Dating.
If radiometric dating methods are as uncertain as we have seen them to
be, then how is it that scientists continue to trust these measurements? Scientists trust radiometric methods
because they have been told by respected authorities that the dates should be
believed, and the practice is now widely accepted.
When a scientist finds a variety of ages, including one number which is
close to the number expected, the scientist is happy to believe it. And the scientist is ready to ignore the
other dates, assuming that they are wrong.
And when a scientist finds that other scientists (by similar imperfect
methods) are coming up with similar dates, they are all happy to pretend that
they know what they are doing. This
is a form of political correctness among scientists.
[In the early days of radiometric dating there was some doubt among
investigators about the validity of radiometric datings, because early results
ranged widely, and different radiometric methods gave different dates. For example, the Uranium-Lead method often gave different
ages from the Potassium-Argon method, etc.
This problem of different methods giving different dates is still around,
but doesn't surface as often, because many researchers have chosen to use only
one radiometric method at a time.]
[Recently the start up of radiometric dating happened all over again. It happened when radiometric methods
were first applied to samples brought back from the Moon. The first generation of radiometric dates varied very widely,
until the investigators had a few conferences, and settled on the numbers they
wanted.]
XIV. So Should We Trust the Scientists?
It is now clear that the radiometric dating methods, that are so often
used to argue that the Earth is millions and millions of years old, are
themselves quite questionable!
By contrast to these methods, there are other uniformitarian dating
methods, which though they are also uncertain, indicate that the Earth is no
more than perhaps ten or at most twenty thousand years old. [see INFINITY #9,
#11 & #13] These methods are generally ignored or discounted by
establishment scientists, because they do not align with establishment
prejudices.
So the age of the Earth and the of universe can not be determined with
confidence by the presently available methods of science. So what are we to do, who should we
believe? Should be trust in uncertain science to tell us the age of
the Earth, and the universe? I
think not.
XV. There is Only One Who Can Tell Us.
When the universe and the Earth came to be, no humans were present to
take notes at the beginning of time. And
no method of science can give us a certain description of what happened.
But the law of increasing disorder proves that the universe did have a
beginning [see INFINITY #2]
and simple logic shows that the universe was created [also INFINITY #2] and logic also
shows that the creator was [and is] a good God [INFINITY #6]. This good God was the only witness
present at the beginning.
So how can we find out what the good God knows about the beginning? If the good creator God has a purpose in
everything, [see also INFINITY #2]
and that purpose includes the creation of beings with independent consciousness
[see INFINITY #6]; which
seems to have been accomplished, in the creation of humans; then is it
reasonable to suppose that such a high intelligence [INFINITY #6], the good
creator God, would leave His created beings ignorant of how their race came
to be?
XVI. Would the Creator Leave His Children Ignorant?
Children ask their parents where they came form. Will a loving parent keep a child
ignorant? Just as a loving parent will not leave a child ignorant, the
father of all living, the good creator God, would not leave His children
ignorant either. He has given an
account of the beginning in the best preserved and most thoroughly verified of
the ancient books, the Holy Bible.
As a scientist and as a Christian, I prefer to rest my belief about the
age of the Earth, about the beginning of all things, on the testimony of the
Holy Scriptures [not on the uncertain speculations of science].
The good creator God tells us that by an act of will, He created all that
is. And He did this just a few
thousands of years ago, no millions or billions of years ago. And He tells us that He created man in His own image [INFINITY #4]
XVII. It's Time to Get Acquainted!
Because He has gone to all the trouble to make the universe, and to make
man, and to tell us about it in His book the Holy Bible, wouldn't it be wise to
get to know this good creator God?
What an opportunity, to learn of the one who knows
everything.
You can get to know the good creator God, by opening the door of your
heart to Him. To begin the process
click here [link to salvation page]
If you are still skeptical, and you need more evidence that there is a
good creator God, and He is the one who gave us the Holy Bible, then please
continue exploring the foundational mysteries of world view with Dr. Truth.