Re: Making Tracks

From: Bill Payne <bpayne15@juno.com>
Date: Mon Apr 05 2004 - 23:30:47 EDT

Hey there, Steve,

When I hit the reply button on your post, I got that vertical line along
the left side, which prevents me from being able to insert responses that
are set off from yours. Kevin was able to set his e-mail to give the
chevrons along the left side, which is more convenient if you are able
and care to do that.

First of all, no one has all of the answers. This is an area of new
research. I'll give you some of the current hypotheses. Researchers
suggest that this megatracksite may represent a general north-south
migration route along the western shore of the mid-continent Cretaceous
sea. The sandy shorelines would be a logical routes for long distant
travel. These individual tracksites are crocodilianso trampled that only
some of the last footprints made at any level are preserved. It has been
proposed that these sandy layers were 'dinoturbated'. The idea that
these sandstones were once beaches is also supported by overlying and
underlying layers with 'crocodilian' tracks, abundant ripple marks, and
extensive burrowing.

I'll agree that your scenario is at first blush a logical explanation for
this data. However, it does have a bit of a "just-so story" flavor. I
guess a more diplomatic way to say that would be to say that you have a
good working hypothesis, we'll see how it fares as the data is
accumulated. What we need is both YECs and OEs both going at the same
data and trying to fit it into their respective models, and critiquing
each other's model. Unfortunately, those two camps don't usually work
together very well.

This megatracksite is a 5-10 meter (15 to 30 feet) thick layer of
sandstone in a sedimentary package that is 3,350 to 4,250 m (11,000 to
14,000 feet) thick. In a one year global flood, we would have to deposit
sediment at an average of 10 meters (30 feet) per day to get this pile.
(In actuality, the rates have to be much higher since this doesn't
include any sediment compaction factors.)

It would probably be higher still. The sediment in the Gulf Coast
geosyncline, if we assume it all came from the current drainage basin
between the Rockies and the Appalachians and up into southern Canada,
would be enough to cover the entire basin to a depth of about 1 mile.
When we are driving around looking at outcrops we tend to forget that
what we are looking at, and where we are standing, was once under a mile
of sediment.

  Under this paradigm, we would have only a few days (at the most
generous estimates) for an enormous herd of recently disembarked
dinosaurs to trample thousands of square miles of sand. The picture that
conventional geology would propose is that the sand was trampled
biannually by migrating dinosaurs for thousands of years. Infrequently,
the tracks would be covered and preserved. When the sea levels would
rise or lower, the trampled beach strand would move farther west or east,
respectively. In this manner, a 5-10 m thick sedimentary package could
be formed covering 1000's of square miles. It didn't happen all at once.

It didn't happen all at once under your scenario. That doesn't mean it
didn't happen all at once.

Note that the tracksites also preserve dinosaur behavior. What we see is
several parallel trails of herbivore (iguanodontid) dinosaurs suggesting
a herd-like behavior. One trail has a large iguanodontid adult walking
slowly on all fours with a parallel trail of a juvenile iguanodontid
walking quickly on its hind legs. (I'm reminded of my kids running to
keep up with their long-legged dad.) The theropod tracks do not come in
parallel trails. These are the carnivores that probably preyed upon the
iguanodontids. I don't know if the theropod tracks represent the
behavior of lone hunters or cooperating pack hunters.

I'm not going to address problems with the ICR Impact-370 article at this
time.

Since you have access to and are familiar with the Morrison, why don't
you take some time and present a reasoned response? That might be
helpful.

It is about the Jurassic Morrison formation at Dinosaur National Park in
Utah/western Colorado. Although we have the type-locality of the
Morrison Formation complete with footprints and dinosaur bones exposed at
Dinosaur Ridge (just a few hundred feet below the track site in the
Dakota sandstone) I chose to limit this discussion to just the one issue
- the extensive upper Dakota megatracksite. (Just let me know if you
really want me to give you the entire sequence of sedimentary rocks
exposed here in Denver along with the potential problems that each
individual formation presents to the YEC paradigm. <grin>)

When in grad school at the U of TN, I went to the U of KY field camp in
Crested Butte, CO, so I do have a little experience with some of these
formations - or at least I did 35 years ago. That was before Crested
Butte was so commercialized - it was an absolutely beautiful summer. At
any rate, if you're game I would love to see the entire sequence, along
with any imagined ;-) problems for YEC.

Since the tracksites are thought to represent migratory trails on
beaches, you might think that we have a problem with food for the
herbivore herds. Actually, in addition to the tracks, ripple marks, and
burrows, the Dakota sandstones contain a large amount of plant fossils
and organic debris. Many of these fossils are well-preserved imprints of
wood. At one site, we actually have the preserved track of a dinosaur
stepping on a stick. Incidentally, the very first discovery of dinosaur
bones in the Morrison Formation, responsible for starting the infamous
fossil bone rush of the late 1800s, was made right here on Dinosaur Ridge
by Arthur Lakes while he was exploring the Dakota Formation for plant
fossils -- As he dropped off the ridge into the Morrison Fm. he stumbled
upon an exposed ~4 ft. long sauropod femur. And finally, when it comes
to swamp plants for herbivorous dinosaur food, the Dakota Formation also
contains some minor interbedded layers of coal! (I'll defer to you and
Kevin on the coal swamp origin arguments.)

That brings up another question. You mention "plant fossils and organic
debris" and "minor interbedded layers of coal." Do you happen to have,
or would it be possible for you to get, a few good photos of the coal, or
a reference in the literature that describes the coal and plants? My
question is, do you have paleosols and bioturbated root zones? From your
descriptions of the organics it sounds like they may be - likely are -
allochthonous. I really don't see where you have enough food production
for the herbivores. A few minor swamps (now interbedded layers of coal)
won't sustain a herbivore dino population.

That's enough for this post. I'll bet that most people on this list have
already hit the delete button long before reading this far. I'll look
forward to hearing your explanations on how rafted dinosaurs can make all
those footprints during so short a time.

Like so many others, you are assuming that the Flood was responsible for
all sedimentary rocks. I'm trying my best to follow the data where it
leads, or actually where it often forces me to go kicking and screaming.
I do admit to taking a YEC approach to my investigations, but in spite of
what Kevin might say, I can be swayed, or will at least give assent to a
superior argument. As far as your "how rafted dinosaurs can make all
those footprints during so short a time", I would say that the Cretaceous
and later strata may be post Flood, and therefore the time frame may not
be so short. You still need to show the food source for the herbivores.
From what you've said so far, it's not there in situ - it looks as if it
was all rafted in.

At this point I don't know how many footprints there really are. If
there was a raft(s) of vegetation with dinosaurs and the dinos got
separated as the raft began to break up, and they landed in different
areas, then widely separated individuals could make tracks that are being
interpreted as migratory. Before you blast me, you need to explain
where/what they ate.

Bill
Received on Mon, 5 Apr 2004 22:30:47 -0500

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