From: alanf@tekig6.PEN.TEK.COM (Alan M Feuerbacher)
Newsgroups: talk.origins
Subject: Re: A Response to the Flood FAQ
Summary: Lake varves confirm ice ages
Date: 16 Dec 92 19:50:29 GMT
Organization: Tektronix, Inc., Beaverton,  OR.

In article <1992Dec15.191142.2201@aurora.com> isaak@aurora.com (Mark Isaak) writes:
>
>Wayne Folta has responded to my flood FAQ by email, raising many points--
>some valid, some not, and some which I can't evaluate myself.  He has given
>me permission to post the email, but the whole thing is too long and diverse
>to post at once, so I'm excerpting parts.  This posting deals with arguments
>from Whitcomb and Morris.  I hope those who are familiar with those specific
>arguments will comment on them.
>
> [....]
>All of the non-quoted material which follows is from Wayne.
>----------------------
>
> [....]
>
>>   How do you explain the formation of varves?  The Green River formation
>> 	in Wyoming contains 20,000,000 annual layers, or varves,
>> 	identical to those being laid down today in certain lakes.
>> 	[From: bill@bessel.as.utexas.edu (William H. Jefferys)]
>
>In Whitcomb & Morris, ("The Genesis Flood"), pages 424-428 talk about the
>Green River formation. The book was written in 1961, so things may have
>changed, but it says that the only real study of the formation was made more
>than thirty years before that by Bradley, with all other papers pointing
>back to this one.
>
>They say that the 6 million years (to deposit) figure was based on Bradley's
>estimates of an ancient drainage basin's size, slope, character,
>erosibility, drainage characteristics, and the amount of water available.
>They also say that the Green River formation has layers that are too thin
>and too uniform over too wide an area to have been deposited in a normal
>lake bed. That is, there are no signs of any stirring up of the sediments or
>of any deposits that reflect flooding conditions where large amounts of
>sediment would have been dumped into the lake and would have sorted out in
>graded series.
>
>They have pictures of true lake deposits and of the Green River shales, and
>the difference in appearance is dramatic. From this, it seems to me that the
>Green River deposits are not what they claim... That a lake sould not have
>been so still and undisturbed form six million years that there is no sign
>in the formations.
>

   The confluence of evidence from widely disparate sources
shows how ancient lake varves correspond with annual varves
being laid down today and during the ice ages.  The follow-
ing material shows this evidence.  Look especially at the
stuff about the Newark Supergroup.

   A theory that has proved resoundingly successful in
explaining the ice ages was first advanced about 1911 by a
Yugoslavian professor of mathematics, Milutin Milankovitch.
He began work on a theory "capable of describing the cli-
mates of earth, Mars, and Venus--today and in the past." To
describe what Milankovitch did, we first must look at the
earth's changing relationship with the sun.  A good explana-
tion of the changes is here paraphrased from Time-Life's
_Ice Ages_.  Unfortunately, the accompanying chart can't be
reproduced here.

   The 100,000 year stretch: The orbit of the earth grad-
   ually stretches from nearly circular to an elliptical
   shape and back again in a cycle of approximately
   100,000 years.  This is called the orbit's eccentric-
   ity.  During the cycle, the distance between earth and
   sun varies by as much as 11.35 million miles.

   The 41,000 year tilt: The earth's axis is never per-
   pendicular to the plane of its orbit; over the course
   of about 41,000 years the angle varies between 21.5
   and 24.5 degrees.  Because of the tilt, the solar
   radiation striking any point on earth fluctuates dur-
   ing the yearly orbit, producing seasons.  When the
   tilt is greatest, summers are hottest, winters are
   coldest.

   The 22,000 year wobble: Even while the shape of its
   orbit and the tilt of its axis are changing, the earth
   wobbles slowly in space, its axis describing a circle
   once every 22,000 years.  Because of this movement,
   known as axial precession or the precession of the
   equinoxes, the distance between the earth and the sun
   in a given season slowly changes. [Windsor  Chorlton,
   _Ice  Ages_, pp. 106-7, Time-Life Books, Alexandria,
   VA, 1983.]

   These variations were calculated mathematically by sev-
eral workers during the latter half of the 19th century.
Milankovitch used the existing calculations of variations in
eccentricity, precession and tilt to calculate how much
solar radiation strikes the surface of the earth during each
season and at each latitude.  He published his first results
in 1920, which contained a graph showing how summer radia-
tion at latitudes 55Deg, 60Deg, and 65Deg North varied over
the past 650,000 years.  His next results were published in
1930, and included radiation curves for each of eight lati-
tudes ranging from 5Deg North to 75Deg North.  The curves
calculated for high latitudes are dominated by the 41,000
year tilt cycle, while those for low latitudes are dominated
by the 22,000 year precession cycle.  By 1941 he had fin-
ished his calculations.  The value of the Milankovitch the-
ory

   was that it made testable predictions about the geo-
   logical record of climate.  It predicted how many ice-
   age deposits geologists would find, and it pinpointed
   when these deposits had been formed during the past
   650,000 years. [John Imbrie and Katherine Palmer Imbrie,
   _Ice Ages: Solving the  Mystery_, p. 113, Enslow
   Publishers, Short Hills, New Jersey, 1979.]

   A number of findings up through the late 1950s threw much
doubt on the Milankovitch theory, but eventually it was con-
firmed.  Here is how:

   _Ice Ages: Solving the Mystery_ gives a detailed account.
While the 100,000 year orbital cycle had become strongly
evident in sea bottom core data, researchers were having
difficulty in showing conclusively that the 41,000-and
22,000-year cycles were actually represented in some of the
sea cores.  Unfortunately, much background information from
_Ice Ages_ is left out in this summary.

   Why was it proving so difficult to find out what the
   higher frequencies in the climatic curves were?
   Reviewing this problem in the fall of 1972, Hays
   thought he knew the reason: the cores that had so far
   been analyzed spectrally (spectral analysis is a math-
   ematical technique also known as Fourier analysis,
   which decomposes a signal into its frequency compo-
   nents).  had accumulated too slowly.  He argued that
   when accumulation rates were as low as one or two mil-
   limeters per century--as they were in most Pacific and
   Caribbean cores--the burrowing activities of animals
   living on the sea floor would blur the record of the
   higher frequency cycles.  To make a valid test of the
   Milankovitch theory, therefore, it would be necessary
   to analyze an undisturbed core whose accumulation rate
   had exceeded two millimeters per century.

   Hays and his CLIMAP colleagues were already studying
   all of the available cores as part of their effort to
   map the ice-age ocean.  After some reflection, Hays
   decided that they would now search for a particular
   type of core: one that had a suitably high sedimenta-
   tion rate--that was located in the high latitudes of
   the southern hemisphere--and that contained shells of
   both forams and radiolaria.  Such a core, Hays rea-
   soned, would provide more information than one located
   in the northern hemisphere.  Variations in the iso-
   topic composition of foram shells would provide a
   record of ice-sheet fluctuations in the northern hemi-
   sphere--for nearly all of the glacial expansion and
   contraction that influenced the isotopic composition
   of the ocean took place there.  At the same time,
   changes in radiolarian populations could be analyzed
   by the multiple-factor technique and made to reveal
   what the history of water temperature had been over
   the coring site.  By comparing the two signals--
   isotopic and radiolarian--Hays hoped to be able to
   answer a question that had first been raised by [19th
   century geologist] James Croll: do climatic changes in
   the southern hemisphere coincide with those in the
   northern hemisphere?

   In January 1973, Hays located a core in the Lamont
   collection that seemed to meet his requirements.  Core
   RC11-120 had been raised from the southern Indian
   Ocean six years earlier by Geoffrey Dickson aboard the
   _Robert Conrad._ After counting the radiolaria and
   sending samples to Shackleton for isotopic analysis,
   Hays was gratified to find that the deposition rate
   was high enough for his purposes (three millimeters
   per century).  When the data were plotted, the answer
   to Croll's question was immediately apparent: climatic
   changes in the northern hemisphere were essentially
   synchronous with those of the southern hemisphere.
   Although this result alone was important enough to
   justify his efforts, Hays was disappointed to find
   that the core only extended back about 300,000 years,
   to the base of Stage 9 in Emiliani's isotopic scheme.
   To provide a suitable record for spectral analysis, a
   core extending back at least 400,000 years would be
   needed.

   When it became clear that the needle Hays was looking
   for was not to be found in the Lamont haystack, he
   decided to search elsewhere.  In July, he went to
   Florida State University in Tallahassee, where an
   extensive collection of Antarctic cores was main-
   tained.  There, he continued the search for cores
   taken near the site of RC11-120.  Soon he came upon
   several cores taken by Norman Watkins aboard the
   _Eltanin_ in 1971.  With the assistance of two gradu-
   ate students, Hays began to open the Watkins cores.
   Later he would recall: "The cores were kept in cold
   storage, and we were all shivering in our parkas.  But
   when core E49-18 was opened, we stopped shivering.  I
   knew right away we had something interesting because
   the color-banding matched perfectly with the oscilla-
   tions in Shackleton's oxygen curve for V23-238."
   Counting down, Hays found that the core extended to
   Stage 13--giving it an age of 450,000 years.  He had
   found his needle at last.

   Hays's off-the-cuff stratigraphic analysis turned out
   to be correct.  Core E49-18 did indeed extend back to
   Stage 13.  Unfortunately, the top three isotopic
   stages had been lost when the core was taken; but with
   the isotope stratigraphy now available, these could be
   patched in from the nearby core RC11-120.  Together,
   these two cores contained a detailed and undisturbed
   record of climate extending back 450,000 years--and
   their accumulation rate was high enough to have pre-
   served cycles as short as 10,000 years.

   When the radiolarian and isotopic data had been
   graphed, Hays and Shackleton were elated.  For the
   isotope curves in the Indian Ocean matched the general
   pattern that Emiliani had established for Stages 1
   through 13 in a number of other cores.  But now, as
   Hays had anticipated, frequencies higher than the
   100,000-year cycle were clearly visible (Figure 40).
   Realizing that an opportunity to make a definitive
   test of the Milankovitch theory was at hand, he asked
   Imbrie to carry out a spectral analysis.

   The first objective was to find out exactly what the
   frequencies of variation in tilt and precession had
   been over the past 450,000 years (Figure 41).  These
   frequencies, rather than the frequency of the eccen-
   tricity cycle, would be crucial to the coming test--
   because they alone were unambiguously predicted by the
   Milankovitch theory.  Imbrie knew that Anandu D.
   Vernekar, at the University of Maryland, had recently
   recalculated the astronomical curves, and Imbrie
   obtained copies of the calculations from him.  After
   processing Vernekar's information statistically,
   Imbrie found that, as expected, the tilt curve showed
   a single cycle of 41,000 years.  But the spectrum for
   the precession curve contained not one, but two dis-
   tinct cycles--a major precessional cycle of 23,000
   years, and a minor cycle of 19,000 years.  Concerned
   that his calculations had been wrong, Imbrie laid his
   results before Belgian astronomer Andre Berger.  After
   examining the trigonometrical formulas from which the
   precession calculations were derived, Berger announced
   that the double cycle that Imbrie had found was not a
   statistical error: variations in earth-sun distance do
   in fact occur as 23,000-year and 19,000-year cycles.

   Berger's endorsement set the wheels in motion.
   According to the expanded version of the astronomical
   theory developed by Mesolella and Kukla, climatic
   oscillations should occur as four distinct cycles: a
   100,000-year cycle corresponding to variations in
   eccentricity; a 41,000-year cycle corresponding to
   variations in axial tilt; and 23,000- and 19,000-year
   cycles corresponding to variations in precession.  In
   the summer of 1974, Imbrie performed the long-awaited
   test.  Spectral analysis indicated that, as expected,
   the dominant climatic pulse was a 100,000-year cycle,
   which appeared on both the isotopic and the radiolar-
   ian spectra as a large peak.  But three other peaks--
   smaller but nevertheless distinct--also appeared on
   the spectra (Figure 42).  On the isotopic spectrum
   these cycles were 43,000 years, 24,000 years, and
   19,000 years long.  On the temperature-radiolarian
   spectrum, they were 42,000 years, 23,000 years, and
   20,000 years long.

   These results were everything for which Imbrie and his
   colleagues had hoped.  Each of the cycles found in the
   Indian Ocean cores matched the predicted cycles within
   five percent.  That such a coincidence might occur by
   chance alone seemed highly unlikely.  Before long,
   Nicklas G. Pisias provided additional evidence in sup-
   port of the astronomical theory.  Using a more power-
   ful spectral method, he found a statistically signifi-
   cant 23,000-year cycle in core V28-238.  CLIMAP inves-
   tigators--realizing that their isotope records from
   the Pacific and Indian oceans matched the correspond-
   ing parts of isotope records already known from other
   oceans--felt justified in concluding that the succes-
   sion of late Pleistocene ice ages had indeed been
   triggered by changes in the earth's eccentricity, pre-
   cession, and tilt.

   Convinced now that major climatic changes were caused
   by astronomical variations, and that the 41,000-year
   and 23,000-year climatic cycles followed systemati-
   cally behind variations in tilt and precession, Hays,
   Imbrie, and Shackleton announced their findings in an
   article in _Science,_ which appeared on December 10,
   1976: "Variations in the Earth's Orbit: Pacemaker of
   the Ice Ages."

   A century after Croll published his theory and 50
   years after Milankovitch mailed his radiation curves
   to Koppen and Wegener, two cores from the Indian Ocean
   confirmed the astronomical theory of the ice ages.  At
   last, geologists had clear evidence that the motions
   of the earth in its orbit around the sun triggered the
   succession of late Pleistocene ice ages.  Exactly how
   this triggering mechanism operated, and why the
   100,000-year cycle of orbital eccentricity appeared to
   be so strongly impressed on the climatic record of the
   last half-million years were still unknown.  But, for
   the moment, it was enough to know that Milutin
   Milankovitch, traveler through distant worlds and
   times, had led the way to solving a major part of the
   ice-age mystery. [ibid. pp. 167-173]

   It is amazing that Milankovitch's mathematical theory,
first published about 1920, could be so accurately confirmed
50 years later by two independent geological phenomena.
This theory was further confirmed in a most unusual way.
After describing how the relatively rapid climatic changes
of the ice ages affected lakes and varve formation, _The
Innocent Assassins_ described lake varves that were found in
ancient lakes:

   With such rapid climatic changes, lakes tend to have
   had a rather short life, just a few tens of thousands
   of years--short, that is, when we start looking at
   lakes that existed before the Ice Age.  We are then
   well back in the Tertiary period, when climatic
   change, as a rule, seems to have been slower, or at
   any rate, not at all extreme.  And we meet with
   chronologies on another scale entirely....  [In many
   ancient lakes] annual varves prove the lakes to have
   existed for hundreds of thousands of years.

   Still, there are longer sequences.  During the Eocene
   epoch, a lake basin formed in North America, covering
   large parts of what are now the states of Colorado,
   Wyoming, and Utah.  The area had previously been tra-
   versed by rivers flowing east, but in connection with
   the rise of the Rocky Mountains a barrier was formed
   to the east.  Thus arose Fossil Lake, and waxed
   greater and greater, finally to cover an area of about
   13,000 square kilometers, with a depth of up to 100
   meters.  It was thus about half the size of Lake Erie,
   and twice that of Great Salt Lake.

   Judging from the sediments that lie beneath and above
   those of Fossil lake, it existed for about one-third
   of the Eocene epoch.  The lake-bottom sediments show a
   fine lamination with alternating light, lime-rich
   bands and dark ones containing a great deal of organic
   matter.  There is also rich fossil flora and fauna
   (especially fish and insects).  The flora indicate a
   climate of a subtropical type with two annual rainy
   seasons, and if the varves are interpreted on that
   basis (two dark bands to a year), it can be seen that
   the entire pile of sediments was formed during a time
   period of 6.5 million years.

   According to radiometric dating, the Eocene epoch
   started about 55 million years ago, and ended about 35
   million years ago.  Its total duration would then be
   about 20 million years.  One-third of that is 6.7 mil-
   lion years, or very close to the number of years that
   can be counted in the lake-bottom silts of Fossil
   Lake.  The agreement is almost too good to be true,
   but there you are.  Radiometric dating is supported by
   the chronology based on annual varves.

   The longest consecutive sequence of annual varves that
   I have happened upon, in a far from systematic search,
   comes from eastern North America and constitutes about
   40 million years.  It dates from the later part of the
   Triassic period and the early part of the Jurassic
   period, and so has an age of about 220-180 million
   years before the present.  My authority is Paul E.
   Olsen.

   The geography of the earth at the beginning of the
   Triassic period was very unlike that of the present
   day.  All continents were then collected into a single
   supercontinent, called Pangaea ("all land").  Then
   began the birth of the Atlantic:  a great rift valley
   running in a northeast-southwest direction started to
   form.  It has its counterpart in the present-day Rift
   Valley of East Africa, which also marks the place of a
   future ocean.  The Triassic valley, a string of at
   least thirteen elongated basins, extended from Nova
   Scotia to North Carolina.  In the basins, very fine-
   grained lake sediments were deposited (forming the so-
   called Newark Supergroup) with annual laminae, total-
   ing some 40 million.  Parts of the rift valley are now
   covered by the sea, but the southern part is dry, as
   are patches further north.

   The sediments preserve a record of climatic changes,
   especially an alternation between dry periods, when
   the water was low, and times of high precipitation and
   high waterlines.  During the former, annual varves
   tend to be very thin, drying cracks are formed, and
   there are numerous footprints of reptiles, in some
   cases so perfectly preserved that you can count the
   scales on the soles.  At high water, the drying cracks
   are absent, and the sediments contain a great amount
   of organic matter, especially fish remains.

   As it happens now, these climatic changes are cycli-
   cal:  they tend to return at regular intervals.  Their
   periodicity is complicated, however, because it is a
   combination of several cycles differing in length.
   (Each cycle represents a sequence from low through
   high to low water.)  The most important periods are
   about 25,000, 44,000, 100,000, and 400,000 years in
   length, respectively.  These are figures that cause
   the geochronologist to smile in recognition.  They
   have to do with changes in the rotation of the earth
   around the sun,

(is this sounding familiar?)

   known from astronomical calculations, and have turned
   out to drive the climatic changes during the Ice Age
   as well--that is, during the last two million years or
   so of earth history.  Now the analysis of the Newark
   Supergroup sediments proves that the same factors
   affected climates as long as 200 million years ago.

   And so the geological time scale, originally dated by
   radiometry, is corroborated by two additional and com-
   pletely independent methods of study:  from analysis
   of annual varves, and from astronomical observations.
   [Bjorn Kurten, _The Innocent Assassins_, pp. 90-94,
   Columbia University Press, New York, 1991.]

   I consider the preceding descriptions--of the confirma-
tion of the Milankovitch theory and its correlation to
ancient lake sediment layers--to be unequivocal evidence
that the ice ages really occurred, over a period of several
million years.  The burden of proof that they did not occur,
and that the Flood produced all the observed evidence, is on
whoever disagrees with this conclusion.

Alan Feuerbacher
alanf@atlas.pen.tek.com