Activity for Geology in the National Parks, in lieu of field trip. Plan to spend a minimum of 5+ hours on these activities.
Part I: Google Earth activities
Travelling to the Grand Canyon.
Go to a big bend in the Colorado River at about 35º49'6.36"N and 113º38'3.38" W. Use the controls to fly down into the canyon. Find the steep Vishnu Schist in the lower part of the canyon. Draw a sketch of the topographic profile of the Canyon. Indicate on your drawing where the Bright Angel Shale lies (remember, it's more easily weathered, making a bench).
Looking from different heights and perspectives: is the river straight or meandering? Explain the significance of this observation.
Go up to the height of the canyon rim and look all around. Based on benches in the canyon, are the rocks mainly horizontal or tilted?
Notice that the highest areas around the canyon are at about the same elevation and very flat (plateau). Explain what this means (what it tells us about the formation of the plateau and canyon).
Look due north. Notice that there is a higher plateau rising in the distance, also flat on top. How did the 2 plateaus form?
Fly due north watching the terrain. You will fly up onto the higher plateau. Comment on any changes in vegetation.
Continue north. Notice how the higher plateau is, in places, dissected by gulley and valleys, with flat topped mesas between the valleys. After a considerable journey, you should see a third higher plateau rising up ahead of you (if necessary, adjust your longitude back to about 113º38'3.38" W). Fly to this. Notice that it consists of a few isolated hills at the higher elevation, leading to a plateau also dissected by rivers.
Continue to about 37º13'36" North (and still about 113º38'3.38" W). You should have crossed a broad valley in the higher plateau and be approaching the high area on the north side of the valley.
What color are the rocks seen in the distance ahead (look at the photos provided) and what might that tell you?
What is the name of one of the state parks?
Travelling to Zion Canyon.
Turn toward the east and fly due east into the highlands area. You should encounter Zion National Park at about 37º12'52.57"N and 112º57'30.15" W.
Follow canyon upstream. Look at several pictures (including of checkerboard mesa and ancient cross-bedded sand dunes).
Checkerboard mesa is at 37º13'26.24"N and 112º53'1.96" W. Turn and look toward the Northeast. You can see crossbedding in the Google image and also in lots of photos available. Try to tell the difference between true beds and crossbedding.
Are the beds horizontal or dipping?
Cite two lines of evidence that these rocks formed in a terrestrial wind-dune environment.
When you have looked at the checkerboard, turn toward the northwest and look at the hill across the valley from checkerboard mesa. Sketch the bluff, including where vegetation occurs. Indicate which layers you think are likely to be permeable and which are impermeable. Explain.
Travelling to Theodore Roosevelt NP.
Go to the park. Theodore Roosevelt NP. Center on the overlook just past the prairie dog town in the south unit (about 46º56'2.58"N and 103º31'58.31" W). Look around from near ground level. Get a feel for the presence of several "base levels", including the mesa you are standing on (same level as across the valley), the level of the modern Little Missouri River, and the top of Sentinel Butte seen to the southwest (same level as the Missouri Plateau to the East). Turn due east and fly toward the Missouri Plateau. You will cross over a tributary to the Little Missouri River. Sketch a cross-sectional view of this valley and a map view of the valley. Explain the process by which the valley formed.
Continuing due east from the overlook, find where the badlands end at the edge of the Missouri Plateau (you will get into farm land). Which is higher elevation, the plains of the Missouri Plateau or the hills of the badlands?
Explain how the badlands formed and how this observation is consistent with that mode of formation.
Return to the original overlook. Go up for an eagle-eye look at the mesa you are "standing" on. Notice how the mesa is dissected by tributary channels flowing into the Little Missouri River. Sketch a map of the mesa, tributary channels, and river, labeling everything.
Return to ground level at the overlook, follow the trail back to the parking lot, then follow the road to the left (going north then northeast). Continue to follow the paved highway, looking for the boundary between the lower Bullion Creek Formation and the upper Sentinel Butte Formation. In the park, the boundary is marked by a distinctive resistant red layer (resistant, therefore it commonly occurs at hilltops), formed long ago when a coal layer burned, causing the rock above it to be sintered and hardened into the red layer. Later, the red layer was exposed by erosion.
Report the exact latitude and longitude where the paved highway goes from being in the Bullion Creek Formation to being in the Sentinel Butte Formation (you may need to look at things from different elevations to determine whether the highway is above or below the red layer.
Report the latitude and longitude where the paved highway goes back down into the red layer and into Bullion Creek Formation:
Go to Buck Hill, North Dakota (highest point in park). Look off due East. Notice how flat the horizon looks. That is the Missouri Plateau. Fly east until you get to the plateau. Are the hills of the badlands higher or lower than the plateau?
Travelling to MacDonnell Range, Australia.
Go to the Ellery Creek Big Hole in the Western MacDonnell Range, Australia (about 23º46'34.80"S and 133º4'24.54"E). Notice how Ellery Creek flows through a gap in the mountain ridge. Given this, which had to come first, the river establishes its path, or the uplift of the mountain? (come on now, do you really think that the river ever flowed up over the mountain?)
Go stand on the East side of the gap and look at the rocks on the West side. What is the angle of dip of the rock layers (0º = horizontal, 90º= vertical).
Look to the South south west. There is another gap there. Travel to it along Ellery Creek (about 23º48'36.85"S and 133º3'55.06"E). As at the other gap, look at the tilt of the rock layers (and notice they are folded a bit).
Back up a ways into the sky until you can see the meanders in the river and the trend of the rock layers and the hills.
Why do you suppose that the hills/mountains trend in the same direction as the strike of the rock layers?
What is the significance of the meandering stream in steep mountains?
Look around a bit. Get a feel for the landscape, the folded rock layers, and how the streams flow across the mountains, but sometimes parallel to the mountains.
Part II: Slideshow Activities
A slide show (NP slide show activity.ppt) is available on my web page. This slide show will only run on the computers in King 216 or CB 209. You need to view the slides in "slide show" mode in order to see the animations.
For each slide, make at least one connection between what's in the slide and something we've learned in class.
Location of going up into Sentinel Butte
46º55'52.87"N and 103º29'07.62" W
Location of going up back down into Red layer
46º55'0.71"N and 103º25'44.05" W