THERE IS NO PHYSICAL CACHE TO BE FOUND AT THIS LOCATION.
You will visit two locations to complete this Earthcache. Between the two points you will take a geological journey back in time when the Catskill region was being impacted by the runoff of the mountains that preceded the Taconic Mountains to your east and a sea to its west. During your journey ponder the following: Was the Catskill region a delta or a seashore? Or both?
EARTHCACHE QUESTIONS
To log this earth cache answer the following questions to the best of your ability and e-mail the answers to the earth-cache owner:
1: What colors are the rocks at the eastern waymost point? What color is on top what color is on bottom?
2: What colors are the rocks at the western waymost point? What color is on top what color is on bottom?
3: At each location: Look at the material the bedock is made of. Does this look like material is river silt or a sea shore? Explain.
4: From the above, and the text below, and considering that it took 20 million years for the beds of material that you stand on to be deposited here: do you feel the Catskill region was formed of material from a river delta, or the sand of a seashore? Or both?
5: (OPTION) Post a picture of a location at one of the two posted points on your journey.
From wikipedia:
HISTORY
The history of the Catskill Mountains is a geologic story come full circle, from erosion, deposition and uplift back to erosion. The Catskill Mountains are more of a dissected plateau than a series of mountain ranges. The sediments that make up the rocks in the Catskills were deposited when the ancient Acadian Mountains in the east were rising and subsequently eroding. The sediments traveled westward and formed a great delta into the sea that was in the area at that time.
Delta
The escarpment of the Catskill Mountains is near the former (landward) edge of this delta, as the sediments deposited in the northeastern areas along the escarpment were deposited above sea level by moving rivers and the Acadian Mountains were located roughly where the Taconics are located today (though significantly larger). The further west you travel, the finer the sediment that was deposited and thus the rocks change from gravel conglomerates to sandstones and shales. Even further west, these fresh water deposits intermingle with shallow marine sandstones and shales until the end in deeper water limestones.
Seashore
The uplift and erosion of the Acadian Mountains was occurring during the Devonian and early Mississippian period (395 to 325 million years ago). Over that time, thousands of feet of these sediments built up, slowly moving the Devonian seashore further and further west.
THE END OF NEW SEDIMENTS
By the middle of the Mississippian period, the uplift stopped and the Acadian Mountains had been eroded so much that sediments no longer flowed across the Catskill Delta. Over time the sediments were buried by more sediments from other areas until the original Devonian and Mississippian sediments were deeply buried and slowly became solid rock. Then the entire area experienced uplift, which caused the sedimentary rocks to begin to erode.
REMNANTS REMAIN
Some traces of the most recent sedimentary layers remain for the discerning eye to discover, however. Fragments of quartzite ranging from bright white, banded orange and tan, to deep red and dark gray are found. Many if not most of these are no more than 6" thick, have two flat sides and are without inclusions of other native rock, e.g., gray or blue sandstone ("bluestone"), most likely indicating the presence of a shallow, wave-beaten sandy delta or beach area at the base of the Acadian ranges in the delta's final stages of sedimentation. That sand layer, mostly free of silt (hence less opaque than older layers formed with higher concentrations of silt and mud under deeper water at more remote reaches of the delta) formed one or more upper layers of the delta. With compression and time, thin layers of sandstone formed of which only the here-mentioned fragments of sandstone remain now though in comparative abundance, if one measures their frequency against those of glacial erratics of similar size and shape which are typically metamorphic in origin (e.g., feldspars, granites, basalts), which most likely originated in the geologically complex region of the Adirondacks to the north.
A CYLICAL PATERN
However, most of the rocks of the Catskill are predominantly red sandstone indicating a large scale terrestrial deposition during the Acadian orogeny. Many beds are cyclical in nature, preserving the record of a dynamic environment during its approximately 20 million years of deposition.
CARVING OF A MOUNTAIN
Over time the sediments were buried by more sediments from other areas until the original Devonian and Mississippian sediments were deeply buried and slowly became solid rock. Then the entire area experienced uplift, which caused the sedimentary rocks to begin to erode. Today, those upper sedimentary rocks have been completely removed, allowing the Devonian and Mississippian rocks to be exposed. Today’s Catskills are a result of the continued erosion of these rocks, both by streams and in the recent past by glaciers.
Sources: http://en.wikipedia.org/wiki/Catskill_Mountains http://3dparks.wr.usgs.gov/nyc/valleyandridge/valleyandridge.htm http://www.fs.fed.us/land/pubs/ecoregions/ch15.html#M212E
http://www.flickr.com/photos/24994567@N06/2471501374/
http://csmres.jmu.edu/geollab/vageol/vahist/catskilenv.html