The Outdoor Geology Classroom, looking northeast. Click here for a map of the area taken from the sign at the site. Each type of material represents each of the five components of the Rock Cycle.
Each rock boulder in each area represents a rock from that component (see below).
The circle with the seating wall is a representation of the Rock Cycle that is explained here.
Exposed aggregate concrete is appropriate for “sediment” because the aggregate is sediment reduced from other rocks. The concrete texture is similar to some sedimentary piles.
Sedimentary and metamorphic rocks were simple to represent because pavers made from those rock categories are commonly produced. Choosing a paver material for igneous rocks was a challenge pavers of those rocks are not produced. They are commonly produced for countertops. Instead, we used pavers of a rock called “migmatite” which is a melted metamorphic rock. The melted product is now frozen within it as granite veins (light-colored component of a relatively dark-colored rock paver).
Ten rock boulders are in the outer arc and seated within their relevant Rock Cycle component, and are explained on the signage at the site. The boulders are:
A. vesicular basalt – it was lava before crystallizing
B. massive quartzite – for minerals found in many rocks
D. granite – for sediment, because much of the components weather to sediment
E. cross-bedded sandstone
F. quartz sandstone
H. brecciated (faulted) gneiss with quartz veins
I. banded gneiss with garnet
J. granitic schist
A boulder of granite is in the “sediment” area because many of the minerals in granite end up either as clastic pieces of sediment in piles (e.g., quartz), or their weathered equivalents do (feldspar weathers to clay minerals).
The other boulders were chosen as the best available examples of the three rock categories. The sedimentary rocks show cross-bedding in both sandstone (E) and dolostone (G). The metamorphic rocks are mostly gneiss with minerals of garnet, sillimanite, and the micas that define the main mineral textures. Boulder (H) is a breccia after faulting (from Tectonics).
Boulders (G) and (I) were generously donated by LaFarge Lockport Quarry of LaFarge-Holcim.
We are thankful for funding courtesy of the SUNY Construction Fund.
