Research • Education • Outreach
“We Look Into the Past”
Jones Geological Services
(717) 887-7103
Email: jonesgeo@comcast.net
Research • Education • Outreach
“We Look Into the Past”
Jones Geological Services
(717) 887-7103
Email: jonesgeo@comcast.net
Fairfield plant is a very interesting quarry. The conglomerate exposed here is probably of Early Paleozoic age, but is surrounded by Triassic and Mesozoic rocks. This would be called a window, where a geologist can see down through the surface rock into older strata. Apparently, the rocks of the Gettysburg basin here were weathered away showing the older formation. Can anyone tell me the theories why “quarry water” always looks bluish-green?
Chickies Rock in Lancaster County is one of the most famous anticlines exposed in the northeastern United States. Now a part of Chickies Rock County Park, the stratigraphy and structure of the exposure has been studied by thousands of students. It is also here that the trace fossil, Scolithus, was discovered by a Mr. Halderman who sent a sample to Charles Darwin for identification. Photo on right credited to Bill Greenawalt.
“Waffle Rock” found on the property of Jennings Randolph Lake in Garrett County, Maryland was a stop on Jeri and Lou Ann’s vacation this summer. They had heard about the rock from friends of theirs and after a 1-hour search of the area, they finally discovered its location. The rock is a sandstone of Pennsylvanian age. During the upheaval of the Appalachian Orogeny, this rock was fractured. The “waffle” pattern is controlled by four separate sets of joints. The joints are filled-in with hematite, thus being more resistant to erosion than the surrounding sandstone. Standing about 7-feet tall, the rock is on display near the dam of the reservoir.
Sideling Hill along Interstate 68, west of Hancock, Maryland is a a classical example of a syncline. Thanks to the State of Maryland for utilizing this resource. They constructed an informational center with wonderful exhibits centered around the geology of the roadcut. Since Jones Geological Services specializes in educational geology, our hats go off to all concerned in operating the information center.
White Rocks, located in Cumberland County south of Boiling Springs contains a great continuous exposure of the Antietam Formation quartzite. The rock is Cambrian in age by the presence of Scolithus work borings. White Rocks is found at the northern terminus of “South Mountain” and the Blue Ridge Mountains. During the winter months, this location provides a nice scenic view of the Cumberland Valley. White Rocks is situated only about 0.25 mile from the Appalachian Trail and Center Point Knob.
Near St. Clair, Pennsylvania is the only site in the only site in the world where Pennsylvanian-aged fern fossils and wood imprints can be found with a white coating. The area once hosted many fossil collectors looking for those museum-quality specimens. Today, the site is closed to collecting according to officials at the Reading Anthracite Company, the owners of the property.