the limestone is removed the Oneota Dolomite is cut into slabs. The
white machine in the above photos is a diamond tipped chain saw about
twelve feet long. In the photo at right a drill (just to the left of
the white saw) is drilling holes to determine the length of the blocks.
In the photo below left a block with the drill holes at the ends has
been removed from the quarry. The photo below right shows many of the
field trip participants inspecting the saw cuts in the dolomite.
|In the photo at the left it is easy to see the natural break
in the layers of the rock. The top part is about two feet thick and is
naturally separated by a thin layer of shale from the lower layer that
is about six feet thick. The layers vary in thickness by the depth of
the water and other environmental changes. These changes are also
responsible for the changes in the color of the rock. The blue gray
rock at the right is just a few feet from the more yellow rock at the
left. In this quarry they are mining four thicknesses of natural seams
of Oneota Dolomite. Each one varies in color, grain characteristics,
porosity and hardness.
Below the layer of dolomite is a layer of Jordan Sandstone