Faith,
There's no need for emotional outbursts. Let me paraphrase you: "If you can't control your emotions, get off this site."
Here's what I gleaned from a little booklet I bought at one of the bookshops near the Grand Canyon, quite a few years ago.
- 2 BYA: sediments and volcanic material accumulated
- 1.7 BYA: mountains are uplifted
- 1.5 BYA: mountains eroded to a nearly level plain
- 1.2 BYA: plain subsided; Grand Canyon Supergroup layers deposited
- 800 MYA: fault block mountains formed
- 700 MYA: mountains eroded to hilly topography
- 600 MYA: area subsided; Paleozoic layers deposited
- 230 MYA: Mezozoic sediments deposited
- 65 MYA: uplift and erosion of mezozoic sediments
- 4 MYA: Colorado river began to cut the Grand Canyon; volcanic activity within the last 1 million years in the western Canyon
So, you see, there
has been erosion of the layers over time. There have even been layers which are now completely gone.
You also need to know that most of the layers were formed in marine circumstances. Of a total of 15 layers mentioned in my booklet, eight have a depositional environment labeled "sea", one is labeled "floodplain", one "swamp" and one "metamorphosed sea sediments". The other layers are labeled "desert", "disconformity", "the great unconformity", and "molten intrusion".
The bottom of a sea is a very tranquil place and can remain that way for millions of years, giving it time enough for sediment to build up undisturbed without being eroded faster than it builds.
This message has been edited by Parasomnium, 16-Mar-2005 10:49 PM
We are all atheists about most of the gods that humanity has ever believed in. Some of us just go one god further. - Richard Dawkins
™ Version 4.2
