The principal consensus among geologists is that the Colorado River basin (of which the Grand Canyon is a part) has developed in the past 40 million years and that the Grand Canyon itself is probably less than five to six million years old (with most of the downcutting occurring in the last two million years). The result of all this erosion is one of the most complete geologic columns on the planet.
The major geologic exposures in Grand Canyon range in age from the 2 billion year old Vishnu Schist at the bottom of the Inner Gorge to the 230 million year old Kaibab Limestone on the Rim. Many of the formations were deposited in warm shallow seas, near-shore environments (such as beaches), and swamps as the seashore repeatedly advanced and retreated over the edge of a proto-North America. Major exceptions include the Permian Coconino Sandstone which was laid down as sand dunes in a desert and several parts of the Supai Group.
The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000 to 10,000 feet (1500 to 3000 m) of uplift of the Colorado Plateaus, starting about 65 million years ago (during the Laramide Orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions).
Weather conditions during the ice ages also increased the amount of water in the Colorado River drainage system. The ancestral Colorado River responded by cutting its channel faster and deeper.
The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion[2].
About one million years ago, volcanic activity (mostly near the western canyon area) deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.
2007-01-03 10:16:10
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answer #1
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answered by The Man With No Face 4
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It is important to draw a distinction between 'religious people' and the extreme fundamentalists who push 'young earth' creationism. The creationists of today are the same sort of people who threw Galileo in jail when he claimed that the earth went around sun because the Bible mentions the 'sun rising' in several places which they felt meant that the sun had to be moving while the earth was still.
However, not all religious people (including myself) believe that. Even today the majority of scientists in the US are Christians. In fact, many of the great geologists who helped determine the ancient age of the canyon rocks - including John W. Powell, Clarence Dutton and Grove Gilbert - were Christians. Unfortunately, as with most religious and political movements, the extremists shout the loudest and get the most headlines and thus give all Christians and religious people a bad name.
As for the Grand Canyon controversy mentioned by the asker...
As an Arizona resident who frequently visits the Grand Canyon, it is true that creationists, quietly backed by the Bush administration, forced the park to sell a creationist book (claiming the canyon was created less than 10,000 years ago in Noah's flood) in the bookshop against the recommendations of the park geologists and scientists (I have seen the book myself).
It is also sadly true, that largely due to this same pressure, if you visit the Grand Canyon today you will see NO MUSEUM or science exhibit there of any sort (the old museum that contained scientifically accurate geology exhibits was quietly closed). It is amazing that one of the biggest attractions in the US and one of the most important and famous geologic sites in the entire world does not have a single museum or detailed geology exhibit.
However, it is a slight exhaggeration to say that park employees are banned from talking about the correct scientific age of the canyon (4-6 million years for the canyon itself, about 2 billion years for the oldest rocks in it). I have been to the canyon within the last year and seen rangers (when asked) give the correct scientific age of the canyon and park geologists still publish accurate reports and studies in scientific journals.
The recent rise of anti-science creationism in the US is sad... not just for Christians, not just for the canyon, but for our entire nation. At no time in the history of the world has technical and scientific research and innovation been more critical to a country staying economically and militarily at the top.
Jet fighters, atomic bombs, high speed computers and communications satellites are not possible without advanced science - and how many of them were invented or developed by creationists using only the Bible as their technical guide? In the last 100 years, how many of the Nobel Prize winners in scientific fields were young-earth creationists? Hint: none.
While public funding for math and science education decline in this country and creationists try to censor scientists and mislead the public about basic scientific research, Europe, China, India and other growing industrial countries that we are competing with are spending billions cranking out more and better scientists with no such roadblocks.
2007-01-03 22:22:34
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answer #2
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answered by sascoaz 6
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I'm a religious person, a religious Jew. I'll give you an answer you'll be happy making fun of for weeks and maybe give the Christians a break.
We have a tradition that there was an enormous species of goat called Reimim, and they were too big by far to get on the ark. They were so big that they ate ceders with one bite. SO Noah let them put there nostrils on the ark, but their feet drug in the water.
Maybe the Reimim drug their feet in Colorado making the Grand Canyon. I think that would put it at like 470o years old. Not sure.
2007-01-03 18:29:57
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answer #3
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answered by 0 3
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I'm a Christian but do not believe that the bible is meant as a science book and I do believe that the park employees should tell how old the canyon is believed to be by science today because as we know sometimes new discoveries change science but still they should be able to tell and as to the book about Noah's Flood it should be sold as religion or opinion and not science. As far as I'm concerned the Grand Canyon is however old the scientist say it is.
2007-01-03 18:19:35
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answer #4
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answered by bess 4
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The Grand Canyon isn't a religion vs science issue. Both agree it is being made by a process called erosion. Making false claims to sell a book isn't a new idea.
God Bless!
2007-01-03 18:24:09
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answer #5
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answered by Anonymous
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15,000 years ago the Grand Canyon was made by an angry swordsman that wanted to vent his frustration on the valleys of Arizona. PS Im a Pagan interested in ancient folklore - just not the folklore of christianity
2007-01-03 18:24:15
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answer #6
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answered by Anonymous
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I am religious, and I believe the Grand Canyon has been formed, and is still being formed, by millions and millions of years of erosion.
2007-01-03 18:21:39
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answer #7
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answered by Shossi 6
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Bush is insane. That man needs to be removed from power before he destroys everything.
The religious don't know how old it is because they aren't willing to accept science as the truth. If they had their way we'd still be in the Dark Ages.
2007-01-03 18:15:40
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answer #8
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answered by Anonymous
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I'm not a "religious" person. I am a follower of Jesus Christ.
No one knows "for sure" the age of the Grand Canyon. Tell ya what, when I get to Heaven, I'll ask.
I must be honest, when I get there it won't be my top priority...but I'll try and remember to ask.
Happy New Year!!!
2007-01-03 18:25:14
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answer #9
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answered by Salvation is a gift, Eph 2:8-9 6
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10 days
2007-01-03 18:15:38
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answer #10
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answered by Anonymous
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