The Northeast Section AIPG
Presents the 2000 Spring Meeting
At Blue Circle Cement
Route 9W Ravena, NY
12:30 p.m. to 8:00 p.m.
Wednesday, May 17, 2000
The Spring Meeting will begin with a field trip to Blue Circle Cement to
tour a limestone rock quarry and a cement plant. A joint meeting with the
Hudson Mohawk Professional Geologists' Association will follow the field
trip. Blue Circle Cement is one of four active cement quarries in New
England and New York. The quarry mines limestones from the Middle Devonian
Helderberg Group, a group of limestones with varying chemical
compositions. The lowest two formations, the Manlius and Coeymans
limestones, are the main units being mined for cement raw material.
Overlying the Manlius and Coeymans limestones are the Kalkberg and New
Scotland formations, two relatively impure limestones that have high
silica contents. The Kalkberg and New Scotland Formations are stripped off
the underlying units and are either stockpiled as overburden waste or used
for aggregate by Callanan Industries. Geologists on the trip will be able
to see the complete sequence of formations from the base of the Manlius to
the top of the Becraft. Within the sequence fossil humters may be able to
find the type fossil for the Coeymans Formation (Gypidula coeymanensis).