95 million year old crocodile unearthed... by a kid with a tractor!

Originally posted by aleon1018
It would be interesting to see what that area looked like back then, I guess we can only imagine. Any close bodies of water there anyway?
[edit on 15-7-2009 by aleon1018]

The area was an estuary; river mouth of a swamp (lots of black clay... I came home stained with black) that was also near a beach of white sand (we have hundreds of layers of white sand (a few grains thick) that are lying in broad sheets throughout the clay. Closest place for water now is the Trinity river, about half a mile away... but 90-100 million years ago this was the Texas beach, with the ocean sitting right where I was sitting yesterday... and will be today.

Good thing it's not here today! It'd make the place lots cooler, but it'd be the dickens to go dig up Madame Crocodile.

Here's the homepage for the site: www.arlingtonarchosaursite.com...

Actual location is kept secret so we don't get vandals. Right now we've got someone sleeping onsite in a camper until we get that croc out of there.

The Dallas Morning News today shows Austin (the kid who made the find and who was getting all those croc teeth yesterday) at work. We were also finding coprolites (dinosaur poo)... I just found a few bones.
www.dallasnews.com...

I understand that you're in Texas. IF it were the same fire that killed the dinosaur, the croc and the turtle ... more than likely it was more than just your casual wild fire. Every species, for the most part, has adapted the fight or flight mechanism and unless these reptiles were in the firefighting brigade, they should have been fleeing the scene. OR the fire may have been part of a bigger catastrophe that stuck rapidly.

An event such as the Chicxulub strike is thought to trigger numerous post-strike effects including seismic and volcanic activity that which is a very real possibility given that Arlington sits near fault lines. Granted, right now these fault lines are nothing compared to the New Madrid, but who knows what the tectonic plates looked like 100 million years ago.

I'm not saying Chicxulub killed these reptiles ... I'm just saying it's not beyond the realm of possibility. I think it's more likely that the Yucatan strike would have suffocated these reptiles before it would have scorched them, but you never know. I'm just really thinking out loud. Like I mentioned before - the dating has a gap of some 30 million years.

Please don't flame me for pointing this out but this creature seems to resemble the description of the Bear Lake monster.

I remember hearing that on the news here (DFW) a few days ago (was it that long?), I had no idea it was that old.

That's awesome you were able to go to the site.

This is great news. Wish I would have known about it while the dig was going on, I would have stopped by. Maybe even brought you some Taco Bueno.

-Dev

Originally posted by sligtlyskeptical
reply to post by Byrd

 

Nice find.

Not to pick on you specifically but I highly doubt the dating on finds such like this. Just like I doubt the distances given for galatic objects. Yeah I know they are grounded in science, but one has to wonder how accurate the science really is. How can you tell that some light arriving to our planet originates from say 100 light years away? Or that a certian carbon content means something is 95 million years old. I find it incredulous that science can spout out these numbers with a straight face.

How much credibility do you give to such dating?

Do you know of or understand the science behind such dating?

If not, then how can you critisize it ?

That is like me saying " How could Albert Einstein come up with all these theories with a straight face" when I infact have no knowledge of how he went about doing it or the science behind it......

Learn more about it before you make statements like that.


That being said, The dating may not be exact and if we find a better method in the future that is more accurate it might show a more accurate date but i doubt it would be too far off.

Nice work Byrd!

When I have more time (two small children atm) or at least when my kids get interested in this stuff, I might look for local groups and volunteer.

Originally posted by sligtlyskeptical
reply to post by Byrd

 

Not to pick on you specifically but I highly doubt the dating on finds such like this. Just like I doubt the distances given for galatic objects. Yeah I know they are grounded in science, but one has to wonder how accurate the science really is. How can you tell that some light arriving to our planet originates from say 100 light years away? Or that a certian carbon content means something is 95 million years old. I find it incredulous that science can spout out these numbers with a straight face.

How much credibility do you give to such dating?

There are two ways to measure the distance of stars without actually going to them. Here is link that explains that mystery.

Also follow this link to see more about dating of dinosaurs. On the second page you'll find more details why C-14 dating will not work. (as Byrd said, it works only till about 50K years)

[edit on 7/16/09 by vietifulJoe]

That's really, really cool.

Hope you get as much as you can on your dig, it would be a real shame to lose half of a skeleton to developers! No poetry...

I think I might have to get involved here in Britain, lots of stuff down on the South 'Jurassic' Coast!

Have fun!

Thanks for posting that.

It sounds like it would be pretty exciting stuff to help on a dig like that.

Except for the 109 degree heat.

Originally posted by Byrd

Originally posted by Chemley
Awesome find! I think this is soooo cool! Now that whole dating thing, ehh, maybe not so much. I have trouble believing any "carbon" dating in as much as it has to be inexact by its very nature. But, date away, I say.

We don't carbon date these things. Carbon dating is only good to about 50,000 years. Things older than that are dated differently.

Can you elaborate on this? How exactly are they dated? How accurate is the process?

Definately interesting stuff, keep us posted.

reply to post by sligtlyskeptical


Agree, nice find with the croc, but I doubt very seriously they can set any accurate date on things that have been in the dirt for thousands of years..

Like the say, stars are born every day, yet all we see are stars that have died or are dying.

reply to post by sligtlyskeptical


Not to steer (mooooooo...) this too far off-topic, but since we're talking about science here, this question:

How can you tell that some light arriving to our planet originates from say 100 light years away?

...of yours bears a response, even though it has little to do with archaeology.

Distances to other stars can be estimated through observations of their relative movement as Earth orbits the Sun (parallax) and by the 'red-shift', which is determined by their light. The 'red-shift' is more apparent in the more distant stars, so it fits well with the Hubble Constant calculations. The parallax measurements work better for more near-by stars, obviously.

But, the gist of your concern is likely related to the ability to date archaeological finds on our planet...and I detect a hint of 'creationist' viewpoint in your skepticism?

Radioactive isotope decay is quite well established, it is the foundation for what's called collectively "Carbon Dating". It is, though, not the only method used to determine relative ages of fossils...I suggest further reading on the subject.

edit: Oh dear, didn't see vietiful's post 'til now!!! Well, his/hers is better!!



[edit on 16 July 2009 by weedwhacker]

I wish I found that croc! Would of been cool digging something that old up in back of my yard. Lol.

Croc Dig, Day 2

I got to the site a little after noon (stopped by the Audubon Trinity Center to get a volunteer form and talk to the chief scientist about getting into some of her citizen science projects (I think I'll recommend using Google Earth as one of the tools for the data collection)... including some herpetology surveys. So, expect a report from me about hunting snakes later this year and one about setting up dragonfly surveys.

Volunteers can have a lot of fun.

Since I was arriving at noon, I stopped at a convenience store and got a 12 pack of cold water; it felt hotter than yesterday and we'd need all the water we could get. I ate a quick lunch -- you need food, but not something full of fats and salts and carbohydrates that will make you feel ill in the heat.

The crew was smaller today. We'd dug around the major piles of bones so that the big ones sat up on little "mesas" or "islands" of mudstone. Roger, the crew chief, photographed the layout, then set up stakes in a quadrant so we could bag things from each section separately. About 2pm, Art and I started taking the bones out of two of the sections.

Fossilized bones aren't neat, elegantly shaped things like you see in the movies or on tv. They're grotty, crumbly, mysterious objects that are almost the same texture and color as everything else buried in that dirt. As we removed the top (obvious) bones, other bones came to light. We wrapped them in paper napkins and wrapped that in tinfoil and put the pieces in baggies. They'll be taken to the university's museum where students will learn to clean the bones. Later, they'll be put on display.

They should have most of the bones taken out today; the crew shows up as they can (some work regular jobs and are coming out after they've had dinner). The large bones will be taken out tonight (if they can) and most of "Mr. Croc, Junior croc (mostly teeth) and their friends the turtles" will be safely at the museum by the end of the weekend.

It was pretty darn hot out there; when I got into the car, the thermometer read 114. I believe it, too.

Originally posted by Byrd
It was pretty darn hot out there; when I got into the car, the thermometer read 114. I believe it, too.

There was something so hot about the heat today (I know that sounds weird). Usually I'm okay with the heat, but I went outside today and turned back around and went back inside. I can't imagine being outside for several hours like you did.

A Guide to Dig Etiquette for Volunteers

So ya wanna go to a dig? Woohoo! Great! Here's some tips:

* contact the group FIRST. Don't go out unannounced.
* ask what you should bring (tools, etc.)
* dress in jeans, sneakers, and tee shirt.
* If the dig doesn't have a tarp, wear long sleeves, put on sunscreen, and you might take an umbrella (I have a beach umbrella I can take.)
* most digs are kid-friendly (we had some scout groups out earlier this year). Let them know if you're bringing a kid (8 years old is a good age to start)... bring water and sunscreen for the kids (and bug spray) and keep an eye on them. Kids are often good at spotting some of the smaller material. We do expect, however, that they're well behaved and follow instructions and will stay out of certain areas.
* take gardening gloves, just in case. Digging can be hard on the hands.
* Wait to see what tools they're using on the site; in the mudstone at our site, an ordinary screwdriver and paint scraper are most useful for removing dirt and trowels are useful for shoveling dirt into buckets. Later, you can bring your own tools.
* you can take a pad to sit on if you like.
* take something to drink. Then triple that amount. Water, sports drink, vitamin water are all good. Avoid caffeine drinks because they'll dehydrate you.
* if you will be walking through weeds, WEAR BUG SPRAY. If you don't have Lyme Disease, you don't need to get it.

When you show up on site, ask to speak to your contact person. Ask the crew chief where they want you.

Be prepared to be put in a section where they don't expect much bone to be found. This is nothing against you. You will end up moving a lot of dirt (we all do), but it's useful to know if an area is devoid of fossils.

You are going to do a lot of sitting, standing up, hauling buckets of dirt, and digging. If you dug it, you go put that dirt on the dirt pile.

When you find something, take it to the more experienced members and ask them what it is. You will be astonished how much bone looks like rock... and how rock can form shapes that will fool almost anyone. Folks don't mind identifying material.

Be curious... ask how they know things, ask what the bones are and how they can tell which bone it is. Everyone loves to teach new folks, and if you stick with it you will eventually be one of the "old hands" who will be helping along new people.

Let them know ahead of time about how long you will stay. On your first visit, it's okay to commit to 2 hours or 90 minutes (I'd do at least that) to get a "feel" for it.

Digging out bones is a very delicate task. When you find your first bone, ask others to train you how to remove it.

That's the basics. Remember that these digs are often under-funded and volunteers are welcomed. This gets you into the "network" and you will find opportunities to do other fun and interesting things.

Oh yeah... you'll get VERY dirty. So will your clothes. After 4 hours at the dig, I looked like something the cat dragged over five miles of bad road. I'm not a very feminine woman, so the fact that my fingernails were chipped unto the dickens didn't worry me; I just filed them short.

I'll put some photos in this thread later on this evening...right now, I kinda want to sit and rehydrate and read.

Originally posted by AcesInTheHole
Can you elaborate on this? How exactly are they dated? How accurate is the process?

As with any dating, the time period is always plus or minus 10%. So, in news stories where they find the bones of a person they think might have been murdered (but no ID), they know from the condition of the bones and other things around the body that they can estimate a 5 to 10 year "window" of time when that person died. So... the body might have been dumped any time from 1950 to 1955 (as an example).

No forensic process can say "they died on February 1st, 1804 at 3 pm."

Same with dinosaurs and all.

In brief, what they do is date the formation by a variety of means. They don't come to the geologic dating by just looking at where the rocks are and saying, "oh. 100 million years." To date a formation, you have to know where it appears, in what context it appears, what makes up the rock (for the Woodbine formation, for instance, there's a lot of volcanic ash mixed in with it. They can use some radioisotope dating and they will also use common fossils to help date things. For instance, if the formation has trilobites in it, we know that it is over 200 million years old.

Geology is one of the most amazing studies around because rocks and dirt do such funky things. In the case of the Woodbine, it's fairly thick up here in North Texas, but it's in just a narrow band. It's overlain by enormous beds of limestone in some areas; in other places it's eroded away and the particles have become part of other rocks and other formations.

Woodbine's also interesting because it's an aquifer, so the mudstone is slightly moist (no, the water isn't ancient; water continually flows ... seeps... creeps... through it) and dries out after you expose it:
www.beg.utexas.edu...

The Woodbine was dated by a number of methods... the details are in things called "technical papers" and they're pretty technical and almost unreadable unless you're a geologist.
gsa.confex.com...

When talking to the press, they usually give out the "95 million year" figure, because it's in the middle of the range. The actual date range (because we're talking in millions of years) is 90-100 million years.

Remember these are 3D bones... if you dated the bottom of the layer of mudstone that the bone rests on, it might say "100 million years." If you dated the top layer (just 1 1/2 inches above), that might be "90 million years." If a dinosaur or croc had stepped on the bone (this happens VERY frequently) and drove it downward, you might find the sediment that it was pushed into was "180 million years old.) But the actual date of death of the animal might be 95 or 98 million years... or 89 million years.

They didn't leave diaries, alas, so at this point we can't be more precise.

Originally posted by tyranny22
I understand that you're in Texas. IF it were the same fire that killed the dinosaur, the croc and the turtle ... more than likely it was more than just your casual wild fire.

The paleontologists know there was at least one (and possibly more) very large and very hot fire that covered a very large area of North Texas during this time. So, yes, it wasn't something casual.

OR the fire may have been part of a bigger catastrophe that stuck rapidly.

No, this is strictly local. Other areas in the Woodbine formation don't show the same pattern... if it was a bigger catastrophe, the evidence would be all over the soft mudstones and clays of the Woodbine formation.

I'm not saying Chicxulub killed these reptiles ... I'm just saying it's not beyond the realm of possibility. I think it's more likely that the Yucatan strike would have suffocated these reptiles before it would have scorched them, but you never know. I'm just really thinking out loud. Like I mentioned before - the dating has a gap of some 30 million years.

That type of dinosaur died out a long time before Chicxulub... and back then, Arlington was actually the Texas coastline. 30 million years later, Texas had pretty much risen from the ocean... my Alamosaurus from Big Bend might be a victim of Chicxulub... it's about the right timeframe... but if so, there wasn't a huge zapping of all the dinos because the vertebra I'm working on had been chewed on by something the size of (and with teeth marks like) a T Rex.

reply to post by Byrd


Thanks for the bits of info regarding digs.
Its fantastic that volunteers are welcomed onto the site , something other countries might do well to imitate .

Keep us updated