Much of the topography of this site was formed by glaciers. Running north and south through western McHenry County to Kane County, Marengo Ridge — a glacial moraine left by the last Ice Age — is three miles wide from east to west, and 200 feet thick. Made of sand, gravel, clay, and boulders, it is the westernmost and oldest of the moraines in our region.
How do end moraines form?
Melting at a glacier margin causes the ice to thin, and ground-up rock debris carried in the base of the ice or dragged along beneath the glacier is deposited. When the ice margin remains in the same place for a relatively long time (tens to hundreds of years), enough debris flows to the glacier's leading edge and piles up to form a large end moraine on the landscape.
What are end moraines made of?
The unsorted mixture of debris deposited by a glacier is called till. Most end moraines in Illinois are thick ridges of till. A ground moraine, the relatively flat, low-lying landscape across which the melting glacier retreated, consists of a thinner layer of till. Sheet like deposits of sand and gravel, called outwash plains, were left behind by melt water streams flowing away from the glacier.
To log this cache, please email me the answer to the following questions:
1. At this location, you are standing on what is known as an end moraine. An end moraine is a moraine that forms at the end of the glacier called the snout. How long ago was this deposited here?
2. What is the most visible ridge to the east and when was it deposited?
3. What is the elevation at this location?
4. Please post a picture of yourself with your GPS along with your log.
McHenry County Conservation District Cache Your Way Across McHenry County GeoSeries
Geocaching is a high-tech “treasure hunting” game played throughout the world by adventure seekers equipped with GPS device. The general idea is to locate hidden containers called geocaches or simply caches. Once you find it, take a trinket and leave one of your own behind for the next person. Share your experiences through geoaching.com.
To participate in our program and earn a special District geo-coin, follow these simple steps.
1. Download a McHenry County Conservation District Cache Your Way Across McHenry County Passport from our website (www.mccdistrict.org/web/re-geocache.htm
2. Go to geocaching.com and find the coordinates/info for the program.
3. Start your search and locate a cache using a hand-held GPS unit. Our containers are clear plastic containers and will have official District labels.
4. When you find a cache, log your name on the logbook inside. If you are participating in the program, be sure to write the answer to the question in your passport.
5. There is a special first to find prize in all the caches.
6. A couple of the caches have travel bugs. Please move these bugs along and do not keep them! You will get your own to keep when you finish the program.
7. Complete all the caches and bring your passport to one of our facilities to claim a coin! Be sure to check each facility’s hours at the location before heading to it! Hours and days open vary depending on site.
Prairieview Education Center
Lost Valley Visitor Center
Brookdale Administrative Offices
If you are unable to make it to a facility when it is open, you may also mail it to: McHenry County Conservation District
18410 US Highway 14
Woodstock, IL 60098
Or e-mail a copy to email@example.com
District Geocaching Rules
1. The location can only be in an area open to the public and within 12 feet from a trail.
2. The container must be made of clear material, not to exceed 4" x 8" x 12".
3. Only three caches allowed per District site. Due to environmental reasons, certain sites or areas may be closed to geocaching.
4. The cache may not contain food items, inappropriate, offensive or hazardous material.
5. The cache may not be buried and vegetation or other natural features are not to be disturbed.
6. Caches may be hidden under logs, in tree holes, in/under downed trees, in/under brush, etc. The cache may not be affixed to any man-made structure (bench, sign, pole, fence, water pump, building, etc.) or natural feature (rock, tree, stump, root, etc.) in any manner. This applies to items requiring magnets, tapes, nails, rope/string, staples or anything else to hold them in place.
7. All caches must be removed or renewed at the end of each calendar year.
For a complete list of rules, visit our website www.mccdistrict.org/web/re-geocache.htm
McHenry County Conservation District Information
Visit our website at www.mccdistrict.org or call 815-338-6223 for camping/shelters, 815-479-5779 for educational programs or 815-678-4532 for the Lost Valley Visitor Center