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| Jim Colyer |
 Posted: Wed Jun 27, 2007 8:07 pm Post subject: Grand Canyon |
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Joined: 13 Jan 2005
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Location: Nashville
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The Grand Canyon is in northern Arizona. It was carved by the Colorado River as the land rose. A cake and knife analogy is used. The river is a knife held stationary as the cake is uplifted. The Canyon took 7 million years to carve.
The Grand Canyon is 277 miles long and a mile deep, averaging 10 miles across. It is shaped like a bra or a woman's bosom. Two billion years of Earth's history are exposed. The Canyon continues to widen as the rims disintegrate.
Erosion by water, ice, wind and the course of the Colorado widen the Canyon. Water has the most impact. It gets into cracks between rocks and freezes. The cracks widen, and Canyon walls collapse.
Geologists study rocks. Paleontologists study fossils. Their work overlaps because fossils are found in rocks, an indication that they are the same age.
Rocks can be dated. Even if they could not, it is obvious from the fossil record as we dig deeper into the earth that life was simpler in the past. Only a dogmatist could deny evolution.
Sedimentary rocks were laid down by water. Less complex fossils are found in the different layers as we descend.
Layers of sedimentary rock form when oceans move in and out. Limestone forms when oceans move in. Shale forms when they move out.
Rocks in the Grand Canyon are from the Paleozoic Era. There are no rocks from the Mesozoic or Cenozoic. They either eroded away or were never laid down. That means there are no fossils of birds, reptiles or mammals. No dinosaurs. The Paleozoic is the era of shelled invertebrates. Trilobites flourished in Cambrian seas.
Kaibab Limstone is the top layer at the Canyon. It is 250 million years old. It formed at the bottom of an ocean and contains fossils of marine animals.
Coconino Sandstone is the remnant of sand dunes from 270 million years ago. It contains no fossils. Sandstone is solidified sand.
Hermit shale was deposited 280 million years ago. It contains plant fossils, indicating that it was above water. Shale is solidified mud.
Vishnu Schist at the bottom is 2 billion years old. Schist is metamorphic rock.
Geologic time:
CENOZOIC ERA - Mammals - Present-60 million years ago
MESOZOIC ERA - Reptiles - 60 million-220 million
Birds
Amphibians
Fish
PALEOZOIC ERA - Inverebrates - 220 million-540 million
PALEOZOIC ERA
Permian - 220 million years ago
Pennylvanian - Carboniferous 325 million
Mississippian - Carboniferous 360 million
Devonian - 410 million
Silurian - 440 million
Ordovician - 500 million
Cambrian - 540 million
Precambian Era - Bottom of the Grand Canyon. The oldest fossils are 3 billion year old microbes. The oldest rocks are 3.8 billion. The age of the earth is 4.6 billion.
The Grand Canyon offers the most complete geologic column on the planet. Rock layers are the same on both the north and south rims.
Grand Canyon: The Hidden Secrets 1984 IMAX 37 minutes
Grand Canyon Skywalk
Over the Edge: Death in Grand Canyon
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Jim Colyer wrote Save The Planet |
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| scpg02 |
| Posted: Thu Jun 28, 2007 5:16 pm Post subject: |
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Joined: 28 Jun 2007
Posts: 259
Location: Sacramento
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| The Canyon took 7 million years to carve. |
I've seen suggestions that it was carved quickly do to ice dams breaking. |
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| billiards |
| Posted: Sat Jul 07, 2007 10:59 am Post subject: |
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Ugh.. okay. Well done I s'pose. I don't really know anything about the Grand Canyon, but I'd say that you were probably right cos I do know the rocks at the bottom are old and there's trilobites in the shales.
As for 7 million years to carve, I don't see any reason why it's not an ongoing process, I would like to know where the 7 million figure came from. Do you mean it started being carved away seven million years ago? |
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| marnixR |
| Posted: Sat Jul 07, 2007 11:12 am Post subject: |
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Forum Cosmic Wizard
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| scpg02 wrote: |
| Quote: |
| The Canyon took 7 million years to carve. |
I've seen suggestions that it was carved quickly do to ice dams breaking. |
isn't the grand canyon a bit far south for ice dams, even during the ice ages ?
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| scpg02 |
| Posted: Sat Jul 07, 2007 2:16 pm Post subject: |
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Forum Junior
Joined: 28 Jun 2007
Posts: 259
Location: Sacramento
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| marnixR wrote: |
| scpg02 wrote: |
| Quote: |
| The Canyon took 7 million years to carve. |
I've seen suggestions that it was carved quickly do to ice dams breaking. |
isn't the grand canyon a bit far south for ice dams, even during the ice ages ? |
Well I looked on the web to see if I could find information on it. I hate it when I remember hearing something but don't remember exactly what it was. I had it slightly wrong, it wasn't a lake created by ice dams but it was large lakes rupturing causing extreme erosion in a short period of time.
Seems this idea is mainly dismissed since it is tied to creation theory yet there does seem to be some science to back it up. I would love to see some actual discussion on the idea itself minus the creation part. The concept has been accepted for other geologic areas.
Here is the reference page for one of the sites I found.
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| jackson33 |
| Posted: Sun Jul 08, 2007 1:54 pm Post subject: |
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Forum Professor
Joined: 10 Oct 2006
Posts: 1201
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The Canyons of Arizona through Nevada and well north in Utah, as well as some very long Cliffs and valleys, indicated some geological need for much of there formations. Cliffs (Vermilion, Grand Wash and others) hundreds of miles long, thousands of feet high and valleys very wide, indicate no water could explain formation. Much would be the same in Canyons the exist on the ocean floors or that are seen on our local planets. Keep in mind many of the more recent major lava flows are found just outside these areas as well, along with earth quake fault lines.
Some used to feel, large sections of ice moving south formed many of these Canyon, well before 3-5 or 50 million years ago. In fact the end of the most recent major Ice Age 240 mya and the formations of the Rockies and much of that area are very close on some time lines. We know that the recorded Mini Ice ages of apx. 10 and 110k years ago had some effect, but in determining what happened 240mya as Massive Ice formations should have moved great distances, were still guessing, IMO.
Even here thought, just where on the planet that area was, is also open for discussion.
To the thread author; The Old West, really didn't show up in the places you mentioned. My first travels to those very same places and many more, were from Car trips to Tuscon, to visit my Grandparents from St. Louis. I remember like yesterday the road from Kingman Arizona to the Hoover Dam and in those days the most impressive sight on Earth. From the mountains where Boulder City was developing and looking down across the LV Valley and all those lights....
There is still an old west, Tombstone itself still exist in much the same manner it did in the 1800's, along with many older mining towns in Arizona and Nevada. Those first sights of Vegas and my trips to Tuscon, made my choice to live and be in business in a town with no paved street very easy. Certainly my most memorable years in life. Might add it made me want to learn history and explore the reasons things happen. I thank you for the time it took to write out that trip, the reasons and give me a glimpse of what I what the same feeling may have meant to others... |
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| partystar |
| Posted: Wed Dec 05, 2007 7:15 am Post subject: |
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I've never visit the Grand Canyon but I hope I will one day. I've heard it's a great place. I'm just imagining how it looked in the ice age I think it was gorgeous.
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| KALSTER |
| Posted: Wed Dec 05, 2007 8:19 am Post subject: |
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Joined: 08 Sep 2007
Posts: 1957
Location: South Africa
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| I've seen suggestions that it was carved quickly do to ice dams breaking. |
If I remember correctly, the ice-dam scenario was put forward as a possible cause for massive erosion that had to take place in a short space of time (not creationism in this case). I can’t remember exactly where this is thought to have happened, but don’t think the Grand Canyon was one of them.
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| KALSTER |
| Posted: Wed Dec 05, 2007 8:25 am Post subject: |
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Here is one example:
http://en.wikipedia.org/wiki/Dry_Falls
As far as creationism is concerned, Kent Hovind is one that uses “The Flood” as an explanation for an absurd variety of formations, including the Grand Canyon.
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| Jellyologist |
| Posted: Wed Dec 05, 2007 8:28 am Post subject: |
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Joined: 12 Jan 2007
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an aside: Your,
"Geologists study rocks. Paleontologists study fossils. Their work overlaps..."
I'm a geologist and paleontologist. Most paleontologists are geologists. Paleontology 'is' geology work. It's a bit like there are doctors (geologists) and they do a specific treatment (paleontology).
There are others who pursue paleontological studies (some biology disciplines) but paleontology for the most part is simply geologists doing a task. |
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| Ophiolite |
| Posted: Thu Dec 06, 2007 12:59 pm Post subject: |
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Forum Radioactive Isotope
Joined: 25 Jul 2005
Posts: 4450
Location: Scotland
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| KALSTER wrote: |
| If I remember correctly, the ice-dam scenario was put forward as a possible cause for massive erosion that had to take place in a short space of time (not creationism in this case). I can’t remember exactly where this is thought to have happened, but don’t think the Grand Canyon was one of them. |
The Scablands in the Columbia river basin. The result of the emptying of Lake Agazziz, an ice damned lake from the last glacial epoch.
| partystar wrote: |
| I've never visit the Grand Canyon but I hope I will one day. I've heard it's a great place |
It is amazing. I am not given to profanity, but on seeing it for the first time I was unable to stop saying ****, for the next fifteen minutes. 
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| Orleander |
| Posted: Tue Mar 25, 2008 3:24 pm Post subject: |
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Joined: 25 Mar 2008
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| are they still flooding it or are they done? Did they move the mammals/reptiles before they did so? |
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