Glacial River View
In Iowa, United States
Size:  (not chosen)
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From this point you can see the Des Moines River basin above the normal pool of Saylorville reservoir. During periods of heavy rain or spring snow melt the lake may actually rise 50 feet or more and fill the area between the bluffs on either side of the bridge.
As you look out over the valley you see land that was shaped, in large part, by glaciers that covered Iowa several times over the last 2.5 million years. While these massive ice formations covered the state no water flowed, rivers didn’t exist. The glaciers scoured the landscape, picking up and carrying along material as they advanced southward. As the climate warmed the ice melted and the glaciers retreated, the last one some 10,000 years ago, leaving behind the terrain as we know it today.
When the glacier started melting the water needed some place to go, rivers formed, channels were cut and valleys appeared. In places like this one there were harder formations that couldn’t be easily eroded away so narrow channels formed between bluffs while in other places the terrain was flatter and not as hard, allowing wide valleys with the river meandering over that valley over time.
Also, as the glaciers retreated they left behind mounds and bands of the material that had been pushed ahead of them from as far away as Canada and, all along the way, giant rocks and boulders were deposited. These boulders are known as erratics and have provided many earth caches for the finding. One of the mounds of rocks and soil left behind by the last glacier can be seen in Des Moines where the State Capitol stands.
To claim this Earth Cache please e-mail me the answers to the following questions. If you are so inclined also please upload a picture of yourself with the river to the north in the background.
1. From the map in front of you, what is the name of the furthest south advancement of the last glacier to cover parts of central Iowa, ending near the State Capitol?
2. What is the name given to the glacial band of rocks and soil left behind when a glacier retreats?
3. On a panel on the south side of the bridge at this location is a cartoon dealing with soil erosion, who drew that cartoon?
(No hints available.)
Last Updated: on 4/5/2015 9:46:31 AM Pacific Daylight Time (4:46 PM GMT)
Coordinates are in the WGS84 datum