Oxbow Formation
An oxbow is formed when a river cuts through a meander neck (shown above), shortening the river's course. The old channel is then blocked off as the river deposits silt at either end of this old channel, generally forming an oxbow lake. As flooding occurs, the flood water deposits sediment into the oxbow lakes. Over time, these oxbow lakes become oxbow swamps or marshes (shown below). Eventually, the oxbow swamp loses it's ability to hold water and completely fills with sediment. When this happens, it is referred to as a meander scar.
Meander scars can be a source of fossils as organic material can become trapped in the oxbow lakes during periods of deposition. Meander scars are particularly helpful in determining the age of a river. A young river will have very few or no meander scars, a small flood plain, and usually does not meander. A mature river will meander, have several meander scars, a well defined flood plain. An old age river has even more meander scars, a very wide (up to many miles across) flood plain, and will meander continuously throughout the course of the river.
For more information about the ecology of the river basin's flood plain visit: https://education.nationalgeographic.org/resource/flood-plain/
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Logging Requirements
The posted coordinates will take you to point A (N 44° 19.910 W 085° 50.799) where Manistee River and/or river basin is currently in one of the previously mentioned stages of oxbow formation. Do not descend the slope! While standing here, take a good look at the area below. You can see the oxbow area to the west of the trail.
1) Describe the conditions directly below you at the oxbow (water, vegetation,etc).
2) Estimate the height above the oxbow at which you are standing.
3) Based on what you see, and the descriptions of an oxbow above, at what stage of development is this oxbow (meander neck, oxbow lake, oxbow marsh, or meander scar)? Please explain why you think so.
When you are finished here, walk toward waypoint coordinates for point B (N 44° 19.864 W 085° 50.852). From here you will have a good view of the Manistee River. Do not descend the slope! Observe what you see below and answer the following questions:
4) Describe the conditions directly below you at the river basin (water, vegetation,etc).
5) Estimate the height above the river at which you are standing.
6) Based on what you see, and the descriptions of an oxbow formation above, at what stage of development is this section of river (meander neck, oxbow lake, oxbow marsh, or meander scar)? Please explain why you think so.
In order to log this cache as found, you must visit this earthcache site and perform the above tasks. Then send the answers to us for all 6 questions. Thanks! Enjoy!!!
The Manistee River Trail is administered and maintained by the US Forestry for the Huron-Manistee National Forest. Permission is granted to hide and find geocaches by the US Forestry (as long as the trails are not closed via their website at https://www.fs.usda.gov/hmnf).