Hopedale quartzite EarthCache
-
Difficulty:
-
-
Terrain:
-
Size: 
(other)
Related Web Page
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
Go to the coordinates. This will take you into a quiet neighborhood built by the Draper Corp. around the turn of the last century, but we're looking at something that dates back before the dinosaurs.
This is based on Puddingstone, GC2VJW8, in Jamaica Plain. (visit link) I used to play on these rocks when I was a kid, but there are houses on top of them now so you won’t have that luxury while you are here. You can, and should, do this without trespassing on private property. You can do this from the street or the sidewalk across the street. You will see an outcropping of quartzite. This is Hopedale quartzite. Some think this started out as beach sands on one of the terranes that would eventually come together to assemble the North American continent. This became sandstone and on contact metamorphism, or changing, perhaps with the intrusion of magma that would become Milford granite, crystallized into what we have today. If there were any fossils in the sandstone, they would have been destroyed by this process. Sorry, kids. In places where it has not weathered, you will see sugary quartz crystals. It fractures in a blocky fashion, and this would have made it easy for a quarryman to cut, but it was never quarried commercially. At the bottom is an unconformity, or change, with mica schist below. See a geologic map of the area from the Mass. state geologist to help you with some of the questions. This pdf of the Milford quad should help.
(visit link)
To get credit for this, email me answers to the questions
1. About how old (on the geologic column) are these rocks?
2. What color does this weather to?
3. Although not quarried commercially, Hopedale quartzite was/is still used. Take a walk around the neighborhood and find at least one use for it.
If you enjoyed this and want a geologic map for your copy of Google Earth, go to the USGS and get the .kml file for the state you live in, or are going on vacation in, or you want a geologic map for your living room:
(visit link)
If you want to see the neighborhood being built, go to the Hopedale history page. Go to Home to see more on the town. (visit link)
Additional Hints
(No hints available.)