2005 Erratics in Ohio
Sterling Hill Mine, New Jersey

I found a bunch of glacial erratics of various rock types behind my wife's grandmothers house in Macedonia, Ohio. The photo to the left shows how they were all moved to the fencerow at some time. Before settlement of the area they were probably scattered randomly over the area, dropped in place by a melting Pleistocene glacier. They were transported by this glacier from their outcrops in Canada. They are mostly metamorphic and igneous rocks, which are nothing like the bedrock at this location in Ohio, which is Paleozoic shale and limestone. Below is a table with links to various photos of some of the erratics. They were taken Sept. 2, 2005.
rockcloseup
pegmatite 1closeup
pegmatite 2closeup 1closeup 2
granite 1closeup
granite 2closeup
brecciaanimation
gneiss 1closeup
gneiss 2closeup
gneiss 3closeup











I visited the Sterling Hill Mining Museum in New Jersey on Nov. 19, 2005. It is an old zinc mine currently operated primarily as an educational facility as a non-profit organization. The first photo shows a sloping rock surface, and this is where the ore body was mined from the surface. The ore body was mined down to 2000 feet below the land surface, but most of the shafts and tunnels are now flooded with water. The second photo shows what the rock looks like inside the mine. It is the pre-Cambrian Frankin Marble. The third photo shows a fault plane in one of the tunnels. It is a normal fault. The ore body is cut by another fault as well, and the other half is estimated to be over a mile below the surface. The mine is famous for its fluorescent minerals, including franklinite, willemite, and zincite. The next two photos show examples of what they have, under low-frequency ultraviolet light. The first shows some minerals behind glass. The second shows a large sample of franklinite (I think) with my hand for scale. The museum also has lots of other minerals and interesting rocks and fossils. I was most impressed by the silver ore shown in the last photo. The white bar in the lower left corner is probably about an inch wide.



Copyright 2006 James L. Stuby. All Rights Reserved.