SKYLINE DRIVE
There are countless wonders to behold along your journey.
Terrain 1.0-1.5 ..... All are at overlooks. ..... Most are handicap accessible.
Bring BINOCULARS if you are handicapped and wish to remain in your vehicle.
MAP https://www.nps.gov/shen/planyourvisit/upload/whole_park.pdf
EARTHCACHE REQUIREMENTS
Each cacher must send his/her own answers BEFORE logging a find. Enjoy the journey (learning adventure) as well as the destination (smiley earned). Remember to follow Leave No Trace principles. To get credit for this Earthcache, complete the following tasks:
1. MESSAGE …. What is the difference between the Old Rag Granite and the Catoctin Formation basalt.?
2. MESSAGE …. Compare the crest of Old Rag Mountain with the adjacent crests.
3. LOG …. Post a picture of you or your signature item at or near the posted coords. This picture is your log signature verifying that you were at the earthcache.
OPTIONAL - Please respect the time and effort involved in creating this earthcache by adding A and B to your log.
A. JOURNEY OF THE MIND ... Science explains what we observe. Relate (in your own words) something you found interesting in the reading. This adds to your learning adventure and your log.
B. JOURNEY OF THE HEART ... Art shares our personal experience of what we see. Share something special you found on site, and why it is special to you. This is a memorable addition to your log and will make other hearts smile.
Journeys of Heart and Mind ...
Stories to Touch the Heart and Puzzles to Challenge the Mind / Rainbow Tree Story
THANK YOU Robert L. Badger for permission to use your book for this earthcache.
THANK YOU Tim Taglauer for permission to place this earthcache along Skyline Drive.
OLD RAG GRANITE
Old Rag Granite contains more orthoclase feldspar than granodiorite. It is also coarser-grained. "The quartz grains have a blue-gray color, and veins of blue-gray quartz cut the granite."
ORTHOCLASE FELDSPAR
"Orthoclase, or orthoclase feldspar is an important tectosilicate mineral which forms igneous rock. The name is from the Ancient Greek for "straight fracture," because its two cleavage planes are at right angles to each other. It is a type of potassium feldspar, also known as K-feldspar." Wikipedia
Tectosilicates are the largest mineral group comprising nearly 75% of the Earth's crust.
GRANODIORITE
Granodiorite is a coarse-grained, plutonic rock (intrusive igneous rock) containing quartz and plagioclase, between granite and diorite in composition.
OLD RAG MOUNTAIN
USGS https://pubs.usgs.gov/of/2000/of00-263/of00-263.pdf
Most of the Blue Ridge mountains are part of a continuous chain. Old Rag Mountain, however, stands alone and is not part of a chain.
Old Rag Mountain is underlain by a rock called the Old Rag Granite. Old Rag Granite formed just a little over one billion years ago during a mountain-building event known as the Grenville orogeny. The Grenville orogeny formed a great mountain range that stretched from Mexico to Canada and was perhaps as high as the Rocky Mountains of the western United States. Although Old Rag Granite is now exposed at the surface of the earth, the rock crystallized several tens of miles below the land surface.
Several hundred million years after the Grenville orogeny the earth's crust began to thin, stretch, and eventually split. Basaltic magmas welled up from the earth's mantle through conduits and flowed onto the land surface as lava. This lava cooled quickly into rock known as the Catoctin Formation or "greenstone" exposed to the west of Old Rag Mountain along Skyline Drive. Repeated eruptions of lava eventually covered the earth's surface and the Old Rag Granite with thick layers of volcanic rock.
Continued splitting eventually resulted in the formation of a deep ocean basin to the east of the Grenville mountain range called the lapetus Ocean. This ancient ocean was located in the approximate area of the present day Atlantic Ocean. Rivers draining into the Iapetus Ocean deposited sandy sediments eroded from the Grenville Mountains on top of the Catoctin Formation and underlying Old Rag Granite. These sand particles were later cemented into hard quartzite rock known as the Weverton Formation.
Hard, resistant rocks like the Catoctin and Weverton formations, and the Old Rag Granite, are less susceptible to weathering and erosion and stand tall as mountains.
NOT HANDICAP ACCESSIBLE - Old Rag Mountain by bevnbill79 GC16H3P ... The hike is 7 miles round trip
RESOURCES
Geology Along Skyline Drive by Robert L. Badger 2012 edition
Graphics via Internet Public Domain since no contact info available