The coordinates for this earthcache will take you to a point along the banks of the Fox River in Seney. I regularly fish this stream and thought that it would be interesting to list an earthcache here, based on the river's unique geological history.
The geology of Michigan, including the Fox River watershed, was formed over a vast period of time. The more recent advance and recession of glaciers, however, have done the most to shape the watershed. Land forms in the watershed that have resulted from such glaciation include outwash deposits (stratified deposits of sand and gravel), lacustrine plains (fine sediments deposited on former lakebeds), and moraines (hills formed by the deposition of unsorted debris at the margins of the ice). Several features in Michigan's Upper Peninsula, such as the several hundred small lakes that populate southwestern Schoolcraft county, are the result of glacial recession. This is why the Midwestern United States is as flat and as fertile as it is. The Fox River watershed is fed mostly by a series of small springs which also came about by result of glacial movement.
Erosion of the banks of the Mainstream Fox is occurring at certain points, slowly but surely. Many areas of the bank in the Seney area are spots of most concern. Rivers carry sediment suspended in the water that has been eroded due to the contact between the flowing water and the channel of the river. As the river flows, any change in the speed between one side of the river and the other can cause the start of a meander. As the speed of the water slows at the obstruction, sediment begins to drop out of the water on the slower side. At the same time, the speed of the water increases on the opposite side of the river, and erosion is accelerated. As more sediment is deposited on the inside, and more erosion occurs on the outside, the original bend in the river eventually becomes a meander.
Not too many meanders exist along the Fox River. But, over time, the bends that do exist now will eventually conform to the shape of a meander bend, which will greatly up the speed of the current and continue to erode the banks. Many mature steams (those that have been around for a very long period of time, and are usually very long also) have multiple meander bends due to the same processes. Rivers are usually classified into three types: Youthful, Mature, and Old. Youthful rivers usually have relatively fast currents, are narrower, have no identifiable floodplain, and are typically very cold. Mature rivers are often still fairly narrow, with a U-shaped channel, have a medium velocity, and their path starts to meander due to erosion with narrow floodplains. Old rivers are normally broad, slow-moving, and they have wide floodplains and oxbow lakes.
LOGGING REQUIREMENTS:
Please email me the answers to the following questions through my profile.
1. From your position on the bank would you say that the river is Youthful, Mature, or Old?
2. Take an elevation reading at the posted coords and email me what you find.
3. What might happen at this particular location as the river grows older?
4. [OPTIONAL] Upload with your Found log a picture of you or your GPSr with the Fox in the background.
Special thanks can go to the Michigan DNR for providing me with this information. Enjoy your visit!