Activity
19 - The Geology of the Grand Canyon
Prepared by Greg Perrier, NOVA
Introduction
NOVA has a campus in a virtual world called Second Life. In this activity you will travel on this campus to a model of the Grand Canyon found in Arizona and examine the different sedimentary strata that form the wall of the canyon. By the time you finish this activity you should have a much better understanding and appreciation of this amazing geological feature.
This handout assumes that you are starting at the Main Landing Site on the NOVA campus in Second Life (see image below). Your professor should have provided you with a separate handout that told you how to download the Firestorm program we use for Second Life, how to get an avatar, how to visit an orientation site, and how to get to the landing site on the NOVA campus.
Whenever you wish to exit Second Life, left click on the white X in the red box on the top right of your screen. When you return to Second Life, your avatar will appear at the same location it was when you logged
off.
Security
SL is like a large city. At any time there are about 50,000 people logged in. Most of those people are nice and respectful, but like any city, there are people who might bother you. As long as you stay on the NOVA Island, it is unlikely anyone will bother you. Most the avatars you will see at NOVA are other students or professors, so feel free to chat with them. Be aware that on the campus nudity as well as abuse or harassment of other students will not be tolerated and anyone doing this will be banned from the campus. If someone does bother you, email me (gperrier@nvcc.edu) their avatar name and simply log out of SL and return later. I can block people from coming to the NOVA Island.
Getting to the Grand Canyon on the NOVA campus
At the Main Landing Site you will find a red telephone booth that you can use to move (teleport) to different places on the campus. You want to teleport to the Grand Canyon area. To do this, left click on any red telephone booth. You should find yourself inside the telephone booth. You should see a menu of locations. There are three pages of location listed alphabetically in this menu. Find and click on the Grand Canyon menu option and you will be taken to the correct location.
Activity: The Geology of the Grand Canyon
The Grand Canyon is an amazing geological feature in Arizona that is about a mile deep (1,500 meters) and was created over hundreds of millions of years. Strata of sedimentary rock were laid down during periods when the earth’s climate was warmer than today and the seas were high enough to extend far into the continents. These strata of sandstone, limestone, and shale where laid down from the Precambrian Era (over 750 million years ago) at the bottom of the canyon until the Permian Era (270 million years ago) at the top of the cliffs. Tectonic activity along the convergent boundary between the Pacific and North American plates caused uplifting of these sedimentary strata, changing the course of rivers and giving rise to the current Colorado River which cut a canyon through these strata.
If you arrived at the correct location, you should be standing on a wooden platform at the bottom of the canyon. With the red telephone booth on your right, you should be facing the canyon wall. In front of you is the water of the Colorado River. Off to your left you will see three panels and several sample fossils (see image on next page).
Overview of the Canyon
Go over to the three panels and have a look at them. To zoom in on a panel, hold down the ALT key on your keyboard and put your curser over the panel. Your curser should now be a + sign. Click on the panel while holding the ALT key down and you can now use the wheel on your mouse to zoom in and out.
Find the icon that looks like an eye on the bottom tool bar. Clicking on this opens up your camera controls. You should initially see a box in the top left of your screen. You can drag this box to other places on the screen if you want. The right side of the box provides controls for moving your view up and down as well as right and left. The left side of the box provides controls for rotating your view. You can use the camera controls and the zoom to look at things better.
The panel in the middle provides a general view of the Grand Canyon. The Canyon is about 1,500 meter deep. You can see the Colorado River flowing at the bottom of the canyon and the different colored strata forming the walls of the canyon. Some of the strata are light, some dark, and many are various shades of red. Note how some of the strata are almost vertical while other strata have a significant slope. In this model of the Kaibab trail area there are 14 different strata exposed on the wall of the canyon.
Now zoom in on the panel on the right with the words “Grand Canyon Section” at the top. This diagram shows the different strata of the canyon. The activity you will complete covers the strata from the Grand Canyon Supergroup (strata 1) at the bottom up to the Kaibab Formation (strata 14) at the top. This diagram also provides information about the geological era when the strata was formed and gives a height measure in feet. Read through the list of the 14 strata. As you descend the wall you will get information on each of these strata.
Next zoom in on the panel on the left with the words “Stratigraphic Column Near South Kaibab Trail” on the top. This diagram shows the strata is less detail, but provides information on the age when the strata was formed, the thickness of the strata, and the environment in which the strata formed. These environments fall into three general categories; marine deposits, fluvial – lagoon deposits, and sand dunes. These different types of deposits resulted in the different types of sedimentary rocks found in the Grand Canyon: limestone, shale, and sandstone.
Fossil are found in most of the strata. Go over to the three fossil images and zoom in on them to see them up close. These give you some idea of the fossils you will find in the Grand Canyon. The clam would be in the marine deposits. The insect and plant would be found in the fluvial deposits. The sand dune deposit fossils are tracks left my animals moving over the dunes.
Walk back over to the red telephone booth. On the fence rail behind the telephone booth you will see a panel about another Grand Canyon area in Second Life that has many fun recreational activities. Left click on the panel and accept the Landmark and the notecard. The notecard tells you how to access the landmark and visit these regions. Feel free to do this once you have completed the Grand Canyon activity.
Near this panel you will see a round grey disk on the floor with the white words “TP to the top” over it. Right click on this disk and in
the menu that appears, click on “teleport” in the top left of the menu. This will take you to the top of the canyon.
The Canyon Wall
You should find yourself standing on a wooden platform at the top of the canyon. You will find there a few scattered pine and cedar trees, some chairs around a campfire, and a glass platform looking out over the canyon (see image below). Walk out on the glass platform and look at the canyon. A similar glass platform exist at the real Grand Canyon.
Far below you is the landing platform where you were initially. Descending the wall is a long series of steps with several platforms where you can stand along the way down. In the real Grand Canyon you would walk down a long winding trail with many switchbacks. Because it is difficult for people new to Second Life to not fall off the trail, we have added stairs.
When you are finished looking out over the canyon, go down the first set of stairs and stop on the first platform. Once on the platform you will be looking at the Kaibab Formation. Left click on the sign with the words “Kaibab Formation” and accept the notecard (see image below). Read the notecard to get the information you need on this formation. At the bottom of the notecard you will see two colored squares. Left click on these squares to see an image of the sedimentary rocks of the Kaibab Formation and to see some of the fossils found in these sedimentary rocks. If you click on the minimize (-) sign on the top right of the notecard it will be stored at the top right of your screen.
Clicking on the maximize square will open the notecard again so you can read it. I suggest you minimize each of the notecards that you open so you can access them easily later.
Descending to the next platform is by way of a ladder. To use the ladder, first left click on the ladder and wait until you see a ball appear. Left clicking on this ball will cause your avatar to climb down the ladder. If this seems too difficult, just walk off the platform and drop to the platform below.
The Toroweap Formation is found on the second platform, just below the Kaibab Formation. Again click on the sign with the words “Toroweap Formation” and accept the Notecard. There are also images to view here by clicking on the colored squares at the bottom of the notecard.
Keep descending the stairs, or fly down to each platform. At each platform you will find one or more signs with notecards. Most of these notecards have one or more images with them. Read all the notecards and then answer the questions at the end of this handout. You should copy the answered questions into a separate Word document and attach this to an email you send to your professor.
Finally, stand on the bottom platform and use your camera icon on the toolbar at the bottom of your SL screen to take a photo. Do not save the photo (that cost money) but select the email option and email the photo to your professor. Be sure to type your real name in the title of the email so your professor can give you credit for the photo. If the email option does not work, you can save the image to your computer or flash disk and email it to your professor as an attachment.
You’re done with this activity. Feel free to use the red telephone booth to go to other locations on the NOVA campus and look around.
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