Today, we did a class demonstration with a sand model of what weathering and erosion might look like with respect to the Mississippi River. Tonight, apply what you've learned over the past week in science to help you understand how weather and erosion has effected how the Grand Canyon was formed. 

I also found this website that may help you- it's an animated trip through the Grand Canyon, in case you need some help. 



03/21/2013 3:59pm

I just wanted to watch the video, in the video it showed that giant rainstorms helped form the Grand Canyon, and it showed that the Colorado River weathered through different layers of rock, with the lower layers older than the upper layer.

03/21/2013 4:34pm

I think the Grand Canyon was formed because the Colorado river weathered the Grand Canyon and it may have eroded and the Grand Canyon might have broken down. That is why I think the Grand Canyon is how it is today.

03/21/2013 8:40pm

I also think that that the rocks that have broken down might have been taken with the river and deposited when the water flows out.

03/21/2013 4:35pm

Since the water in the Colorado River will weather the rocks on the two sides away and cause the rocks to erode and form the well-known Grand Canyon. The then rocks form into sediment like the science project we did in school with the sand and water.

03/21/2013 4:42pm

In the video it showed how the Grand Canyon from a bird's eye view. By our discussion in class it showed what we were talking I think rainstorms helped form the Grand Canyon. We talked in class that the more rain it will flood the area and it happened in the experiment. I think maybe the Grand Canyon was made by the Colorado River when loads of water dropped it made particles called sediment.

03/21/2013 5:02pm

In the video there was a rainstorm that showered onto the Grand Canyon. I think that had something to do with it, but more importantly, I think that the huge rainstorm whipped up the Colorado River and made it overflow and WEATHERED the Grand Canyon. Also I think that the rainstorm might've raised the sea level of the Colorado River, which then would've ERODED the Grand Canyon. To relate this with what we did in class today, it would of also carried the sediment and bits of rocks and dirt from the Grand Canyon into nearby lakes such as: Lake Mead in Nevada and Lake Powell in Utah.

03/21/2013 5:04pm

All of this would've changed the Grand Canyon's shape.

03/21/2013 5:15pm

when i watched the video and it reminded me of our science lesson today. when we pored the water into the container the water pushed through and weathered the sand. so maybe in the Colorado river, more and more water was pushing though, causing cracking the rocks and breaking the rocks, widening the area, making the grand canyon.

03/21/2013 5:47pm

Firstly, the Grand Canyon must have changed because of the Colorado River weathering and eroding it. I mean, today in class, think of the sand as the Grand Canyon, and the water as the Colorado river. The water went right through the sand and took of some of the sand. If the area of Arizona where the Grand Canyon is was just a piece of land, then the Colorado River went straight through the middle of it, the river must have weathered the Canyon and eroded it, later making the Grand Canyon. Also rain storms, or any kind of water could have also came along, and weathered the surface of the Canyon. Finally, since the Colorado River goes through other states, it could have brought rocks from the other areas that it goes to (like Utah). This is basically erosion.

Gina M. Moy
03/21/2013 5:49pm

I watched the video as a reference, and in my own words, the Grand Canyon was formed by multiple rainstorms. The rain weathers down the land that makes Grand Canyon. The Grand Canyon can also be weathered by the Colorado River. The Colorado River always rests in the Gand Canyon, eroding the land at the bottom of the river. And eroding is when water or any other agent of weathering picks up land or sediment and moves it somewhere else, just to show that I know what it is.

03/21/2013 5:50pm

I think the Colorado River carved out the Grand Canyon by carrying rocks, sand, etc. somewhere else. Over time, it the water decreased to form the great but not as mighty Colorado River!!!

03/21/2013 5:54pm

Sorry, the last sentence was suppose to be.......Over time, the water decreased ........

03/21/2013 5:50pm

I think the Grand Canyon formed because the Colorado river weathered it and carried the bits of into near by lakes.

03/21/2013 6:01pm

I think the Colorado River weathered the Grand Canyon over time with the water going at a intense pace which made the Canyon what it is today. If the speed was not fast or intense the Canyons features would not be so dramatic. Another factor in how the Canyon was formed was TIME. The river started flowing through the Canyon five million years ago.

Matthew Brown
03/21/2013 7:00pm

What do you mean by intense Deven?

03/21/2013 6:04pm

Fun Facts

- The Colorado river was one of the strongest rivers ever which made it a small mystery how it made a huge gash in Arizona's landscape.

03/21/2013 6:09pm

-The area around the Colorado river are made up of sediment which made it a easy task for the Colorado river to make it's mark.

- Also the Colorado river ripped off huge chunks of earth and rock every year carrying tons of sediment with it.

03/21/2013 6:12pm

To conclude my message i can see why and how water is the strongest type off weathering

03/21/2013 6:45pm

I think that the Grand Canyon was formed by the Colorado River. Because it is running water, and also water is the most powerful agent of weathering. Just like today when we did the experiment with the sand, when the water got poured on top of the sand, the sand didn't just get weathered. Its sediments all got “carried away”, some of the sediment stayed with the sand and some got separated. Then more and more sediments got created, because we poured more water. This is the same thing that happened with the Colorado River but all sediment got separated on to the sides of the river. This happened many times because again this is running water. So, this same thing kept happening and more and more sediment got packed on top of each other and it created the Grand Canyon! But I think that this might not be the only cause. In video it was raining. When the rain froze in the tiny cracks, the rock would expand. I think this might also be one of the reasons the Grand Canyon was formed. This is also a type of physical weathering.

Matthew Brown
03/21/2013 6:58pm

The Colorado River's water would keep flowing over years and as it brushes against the rock and sediment it would pick it up. After that the rock and sediment would go down river ( erosion). It would keep doing this cycle until it carved out the monument we all know today the Grand Canyon.

03/21/2013 6:58pm

In the video it showed that she when weathering had happened its sediments eroded into the Colorado river which made it really dirty, but then it happened to much that the water couldn't take it, there was to much sediment that the water had to ''sink'' in with the other rocks around it. I the video it also showed that it was raining, and maybe it rained a lot and the Colorado River started to flood so the all the rocks slurped the water t themselves that the Colorado river wasn't there anymore.

03/21/2013 7:00pm

The grand canyon got eroded by the Colorado river. The Grand Canyon was in a different shape long ago. The Colorado river flowed through the Grand Canyon, and as it flowed, it weathered the rocks, and carried the smaller pieces of broken rock down stream. The reason why I said that because in class, when the water eroded the sand, it carried bits of it as it flowed. The sand looked totally different from the first time to when we poured the water. Rain helped form the Grand Canyon also, because the water came from above and heavily showered the Grand Canyon, which made it weathered.

03/21/2013 7:02pm

When we did our sand experiment, when Ms.O poured the water on the sand the water eroded the sediments to the basin, when Ms.O put more water and faster the sand couldn't take it I took as many pieces of sediments as can as it erodes. Also in the movie when it rained and had a flood he rocks could have went to the rocks crack and froze it, that could have made the rock expand which took most of the water.

03/21/2013 7:03pm

This is physical weathering.

03/21/2013 7:21pm

It's kinda like in the sand experiment we did in class because the water carved out a "ramp" , while the rain/Colorado River carved out the Grand Canyon.

03/21/2013 7:22pm

In the movie it showed rain and the rain could have got in the rock and expanded and i know that because we learned it in class. the coloradl river could have made the grand canyon well the river could have ran rate up to the canyon before it was a canyon and rivers are not that deep so the water could have got in the rock and made a hole and it got bigger and bigger and the top fell bown

03/21/2013 7:43pm

It probably formed by there being a huge rock kinda like a mountain then ther must have been a flood then it mis have weathered so there probably are some rocks in the water now.

03/21/2013 7:44pm

I'm sorry I ment to say must

Matthew Lai
03/21/2013 7:48pm

I believe that the Colorado River had weathered the rocks and with the length of the downpour it had then eroded the sediment so much that the Colorado River is below ground. I too believe that Solen's idea of Ice Wedging or Cyrofracturing is correct because with the little holes the water can go further.

Matthew Lai
03/21/2013 7:52pm

This is like how the sand was eventually pulled out with little water but with the faster water which is like the rain it get's extra strength weathering and eroding faster.

03/21/2013 7:58pm

Yeah, I also thought that the river got extra strength from the rain, good connection into my thinking.

03/21/2013 8:21pm

A long time ago, I think that the grand canyon was just a HUGE rock... or it was never there till the Colorado river came along! If my first prediction was true then that means that the Colorado river came after the grand canyon. The river would have went VERY fast to carve through such a big rock! If my second prediction was true it would mean that the grand canyon came after the Colorado river. The river could have picked up bits of sediment from the riverbed and one day it could have flooded and all the sediment could have deposited and eventually hardened! My first prediction is more related to our lesson. The river(water) carved through the grand canyon(rock,sand) and left a trail. My second prediction is a little less related,but still related! When the rain fell the river flooded and "deposited" sediment on the ground. I think that my second prediction might be true because the grand canyon is made of "sedimentary" rock.

03/21/2013 8:37pm

I think the Colorado River weathered the Grand Canyon by eroding it- just like what we did in science. When the water went over the sand, it made a rut in the sand.

03/21/2013 8:46pm

I think that the Grand Canyon was formed because the Colorado River weathered away the rock. In school, we learned that erosion is a result of weathering. The Colorado River slowly eroded rock over time, and that formed a canyon that we call the Grand Canyon. Also, when it rains, the rain would add water to the river, which would also help form the Grand Canyon.

03/21/2013 8:53pm

I am reffering to the experiment that we did yesterday with the water and sand. When the water (colorado river) picks up all the sediment and moves it, it left it on the rock which that made the rocks dirty. Also when Ms.O poured the water on the sand it split the sand. That makes me think that if the water poures into the spaces of the rocks it could split the rock, like it did to sand. Or it could make the rock smaller. That is called weathering.

03/21/2013 11:28pm

The fact that the Colorado River was a river with more range over the Grand Canyon, which probably could have been just a heaping mass of sand, and gravel back then, means the power of the old Colorado River could more easily move the rocks of the weaker Grand Canyon. While the rocks were being eroded,they could have stopped at one point, and that piled up to make the pillars. They possibly could have even connected to each other, but the force of the Colorado River pushed out those rocks, and who knows where they are right now.

Matthew Brown
04/23/2013 9:27am

I wonder what will happen in like a billion years? will everything else around the grand canyon be eroded, so the surface level will be similar in height? or will the grand canyon just keep getting bigger? The world may never know....

Comments are closed.