Thursday, April 11, 2013

History of Man: Resolving the Timelines part 1


We have now come up against a roadblock.
  • Secular scientists have a timeline that's 13.7 billion years long.
  • We have a timeline that is 6188 years long.
Quite a difference!  And there doesn't seem to be an easy way to get the two to meet.  Why?
  • We have scripture
  • They have dating methods that seem to be reliable.

But in truth, the dating methods are rarely reliable.

DATING METHODS

Here are some of the most obvious dating methods that are used to obtain dates for geologic history (in no specific order):
  • Radiometric dating other than radiocarbon dating.
  • Ice cores in Greenland and the Antarctic.
  • Dendrochonology (tree ring dating).
  • Stratigraphy
  • Fossil record
  • Written texts and coins
  • Radiocarbon dating

Then these dating methods are used by
  • Geologists, physicists, and chemists
  • Archaeologists
  • Paleontologists and palnyologists
  • Paleoanthropologists
 
…and unfortunately they sometimes don’t agree.

Scientific research works in the present on evidence that exists in the present.  Any conclusions about the past MUST rest on assumptions.  All dating methods are based on these assumptions.  Some have more than others.  Let’s look at the different methods and check their validity.  I will give you the major assumptions that are made for each one, and at least one example of evidence dated by those methods that is known to be incorrect.

Radiometric dating
Used to date igneous rock
Uses radioactive decay for the measuring tool
Types: U-Pb (two types), K-Ar, Rb-Sr, and Sa-Ne
Assumptions:
  • Heat forced all the daughter element out of the molten rock
  • Once the molten rock cools, no more daughter element escapes
  • Initial conditions are known
  • Amounts of parent and daughter elements have only changed because of decay
  • Rate of decay remains constant.
Usually yields dates of millions of years, sometimes billions of years
Examples of known dating errors:
  • Lava flows from Mount St Helens (1986) dated at 350,000 years
  • Lava flows from Mount Ngauruhoe, NZ, (less than 50 years ago) dated at 3.5 million years

Radiocarbon dating
This is a type of radiometric dating that measures decay of C to N and has narrow uses
Can only be used on items that were formerly living…wood, baskets, bone (not fossilized), etc
There is a limit to the accuracy of this method because of the extremely short half-life of C14.
Assumptions
  • The same as other radiometic dating methods
  • Influx and outflow of C14 in the biosphere is in equilibrium
Examples of known dating errors
  • Two separate samples of a single dinosaur bone dated at 9890 years and 16,120 years
  • Freshly killed seal dated at 1300 years
  • Living penguin tissue dated at 8000 years

Ice Cores
Layers of ice are seen in Greenland and Antarctica
Assumptions
  • Ice has been there for as much as 2.5 million years
  • Layers are annual layers
  • Precipitation rates are similar to today’s
Examples of known dating errors:
  • Two World War II planes that crash landed on Greenland were located 250 feet deep in ice.  If ice were to accumulate 250 feet in 50 years, then the entire Greenland ice cap would be less than 1000 years old.

Dendrochronology
Used to supplement radiocarbon dating and “correct” its dates.
Uses tree ring counting to determine date the tree was cut down.
Tree ring width is determined by weather conditions.
Begins with the C14 date
Assumptions
  • Trees put on one ring per year
  • One can use the tree ring patterns from trees of one region to overlap and match those from another region
  • Radiocarbon dating is accurate
Examples of known dating errors:
  • A wooden building from Dalecarlia, Sweden, was dated as being built in about 1240, and refurbished in the 1490’s, 1570’s and 1930’s.  Yet a wooden building in that climate cannot last that long.

Stratigraphy and the Fossil Record
This method defines layers of sedimentary rock, and identifies the fossils present
Certain layers of rock contain particular fossils that are in no other layers.  These are index fossils.
Assumptions
  • Sediments were laid down at the same rate in the past as they are today.
  • Sediments were laid down slowly
  • Index fossils are used to date rock layers
  • Rock layers are defined by the index fossils
  • Evolution is true
  • Uniformitarianism is true
Examples of known dating errors
  • Man-made artifacts in layers that predate the supposed appearance of man

Artifacts and Inscription Evidence
These are dated much the same as fossils, although this evidence is in much shallower levels. 
Some artifacts can be dated by C14 dating…for example, basketry, leather clothing, papyrus documents, etc
Assumptions
  • Preconceived notion as to the supposed evolution of man
  • Preconceived notion as to the Stone Age, Bronze Age, and Iron Age dating for certain areas
Problems exist with this evidence, because if a new finding disagrees with the presuppositions, evidence is often discounted (or discarded!)

 
It is the commitment to
  • a big bang origin of the universe
  • and old earth, and
  • evolution
that determines how secular scientists choose to date history.  For as many dating methods as give ages of millions or billions of years, there are as many that give dates under 10,000 years, and some of those are as short as 150 years!  We know that the earth is older than that!  Obviously, there are problems with these methods and care should be exercised in relying on them.
 
What we want to do is attempt to reconcile the differences between these two timelines.
 
I once got a comment that it would be nice to have a "cheat sheet" card that gave a conversion table for the dates so that when one was reading a book and it said "x-number of years," there would be a way to convert that to a biblical time scale.  It's not quite that simple, but this will be our goal...to get as close to that as we can.

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