Church Street Erratics EarthCache
Cachin' Bandit: Erratic moved on. Deleted found logs of people who still claimed a find but also said it wasn't there and that it should be archived.
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
This earthcache is located along a country road at the edge of a field.
This earthcache takes you to a erratic rock that was placed here when the Bloomington moraine was "retreating" from its southernmost position. When a glacier moves forward it picks up chunks of bedrock as it moves bring them with it as it moves forward. When the glacier melts and retreats it drops these boulders as the ice melts. Some are even buried under the ground. As the ground freezes and thaws it can slowly bring these buried erratics to the surface. As these erratics came to the surface the farmers plow finally hit the erratics which where moved to the edge of the field next to the road.
You may be asking,"What is a erratic, and how did it get here?" Well this is what I learned.
These exotic rocks came from Canada and the states north of us. The continental glaciers of the Great Ice Age scoured and scraped the land surface as they advanced, pushing up chunks of bedrock and grinding them against each other or along the ground surface as the rock-laden ice sheets pushed southward. Sometimes you can tell where the erratic originally came from by determining the kind of rock it is. A large boulder of granite, gneiss, or other igneous or metamorphic rock may have come from Canada. Some erratics containing flecks of copper were probably transported here from the "Copper Range" of the upper peninsula of Michigan. Large pieces of copper have been found in glacial deposits of central and northern Illinois. Light gray to white quartzite boulders with beautiful, rounded pebbles of red jasper came from Ontario, Canada. Purplish pieces of quartzite, some of them banded, probably originated in Wisconsin. Most interesting are the few large boulders of Canadian tillite. Glacial till is an unsorted and unlayered mixture of clay, sand, gravel, and boulders that vary widely in size and shape. Tillite is glacial till that was deposited by a glacier many millions of years older than the ones that invaded our state during the Great Ice Age. This glacial till has been around so long that it has hardened into a gray to greenish gray rock containing a mixture of grains of different sizes and scattered pebbles of various types and sizes.
Many boulders were probably dropped directly from the melting front of the glacier. Others may have been rafted to their present resting places by icebergs in ancient lakes or on floodwaters of some long-vanished stream as it poured from a glacier. Still others, buried in the glacial deposits, could have worked their way up to the land surface as the surrounding loose soil repeatedly froze and thawed. When the freezing ground expands, pieces of rock tend to be pushed upward, where they are more easily reached by the farmer's plow and also more likely to be exposed by erosion.
To log this earthcache you must email me the following answers. Please don't post them on the cache page. Tell me how many erratics are at the location? What is the odd ball item mixed in with them? What type of erratics do you think these are? Post a picture of you with your GPS next to a erratic.
Additional Hints
(No hints available.)