CAUTION: You should prepare yourself for the hike. Wear proper footwear, take water to drink, This is a developed trail one mile long to the bottom of the gorge, but it's steep and can be slippery. PLEASE, STAY ON THE TRAIL - DO NOT TAKE SHORT CUTS. Not only will you risk serious injury, but you will trample fragile vegetation and promote unnecessary erosion. Do not attempt this trail in the winter or early spring when ice is present.
The coordinates will bring you to the Turkey Path trailhead and the first step of your journey back in time. When you make your 1 mile decent into the gorge, you will see rocks that were deposited over 350 million years ago by an inland sea. The views are wonderful the entire trip and you'll get to see a good portion of the canyon from top to bottom. As the trail takes you down through the forest, it passes along nearly vertical cliffs on the canyon wall. The first rocks you will see are sandstones, they are the hardest and were formed from beach sands. They make up the rock outcroppings and cliffs at the vista. As you reach the 1/2 mile mark you'll find scenic waterfalls along the path on Little Fourmile Run. Stop somewhere along the trail and take a picture of yourself there (STAY ON THE TRAIL) with a waterfall in the background and observe the waterfalls as part of the requirement to log this EarthCache. Pay particular attention to the cracks or joints in the bedrock. Geologists refer to these joints as "fractures". The cracks form parallel surfaces called joint planes. The rocks here are shale, siltstone, sandstone, and conglomerate. Farther down, you'll find a red shale and siltstone that is relatively soft and easily eroded, which helped to form the Pine Creek Gorge. These mudstones and shales hardened from muck on the sea bottom. At the base of the canyon, the lowest and oldest stone is a gray to green-brown siltstone and shale over 400 million years old. You may find marine fossils here, but please don't collect them. Leave them to be discovered by the next visitors as well.
To log this EarthCache cachers must:
1) Identify the Class of Waterfalls you see along Little Fourmile Run
2) Briefly describe how the fractures have effected the shape of the falls.
3) Post a picture of you or your party in view of the waterfalls
Picture should be posted with your log, but answers should not. Please email your answers to me.
*Failure to fulfill the EarthCache requirements may result in your log being deleted.*
10 Classes of Waterfalls
Block: Water descends from a relatively wide stream or river.
Cascade: Water descends a series of rock steps.
Cataract: A large waterfall.
Fan: Water spreads horizontally as it descends while remaining in contact with bedrock.
Horsetail: Descending water maintains some contact with bedrock.
Plunge: Water descends vertically, losing contact with the bedrock surface.
Punchbowl: Water descends in a constricted form, then spreads out in a wider pool.
Segmented: Distinctly separate flows of water form as it descends.
Tiered:Water drops in a series of distinct steps or falls.
Multi-step: A series of waterfalls one after another of roughly the same size each with its own sunken plunge pool.
Scientific information:
Although the rock formations exposed in Leonard Harrison State Park and the Pine Creek Gorge are at least 300 million years old, the gorge itself formed only about 20,000 years ago, in the last ice age. Pine Creek had flowed northeasterly until then, but was dammed by rocks, soil, ice, and other debris deposited by the receding Laurentide Continental Glacier. The dammed creek formed a lake near the present village of Ansonia, and the lake's glacial meltwater overflowed the debris dam, which caused a reversal of the flow of Pine Creek. The creek flooded to the south and quickly carved a deep channel on its way to the West Branch Susquehanna River.
A waterfall on Little Fourmile Run in the park flows over layers of ancient rock.The park is on the Allegheny Plateau, which formed in the Alleghenian orogeny some 300 million years ago, when Gondwana (modern Europe and Africa) collided with North America, forming Pangaea. While the gorge and its surroundings appear mountainous, these are not true mountains: instead years of erosion have made this a dissected plateau, causing the "mountainous" terrain seen today. The hardest of the ancient rocks are on top of the ridges, while the softer rocks eroded away forming the valleys.
The land on which Leonard Harrison State Park sits has undergone tremendous change over the last 400 million years. It was once part of the coastline of a shallow sea that covered a great portion of what is now North America. The high mountains to the east of the sea gradually eroded, causing a buildup of sediment made up primarily of clay, sand and gravel. Tremendous pressure on the sediment caused the formation of the rocks that are found today in the Pine Creek drainage basin: sandstone, shale, conglomerates, limestone, and coal.
Five major rock formations are present in Leonard Harrison State Park, from the Devonian and Carboniferous periods. The youngest of these, which forms the highest points in the park and along the gorge, is the early Pennsylvanian Pottsville Formation, a gray conglomerate that may contain sandstone, siltstone, and shale, as well as anthracite coal. Low-sulfur coal was once mined at three locations within the Pine Creek watershed. Below this is the late Mississippian Mauch Chunk Formation, which is formed with grayish-red shale, siltstone, sandstone, and conglomerate. Millstones were once carved from the exposed sections of this conglomerate. Together the Pottsville and Mauch Chunk formations are some 300 feet (91 m) thick. Next below these is the late Devonian and early Mississippian Huntley Mountain Formation, which is made of relatively soft grayish-red shale and olive-gray sandstone. This is relatively hard rock and forms many of the ridges. Below this is the red shale and siltstone of the Catskill Formation, about 760 feet (230 m) thick and some 375 million years old. This layer is relatively soft and easily eroded, which helped to form the Pine Creek Gorge. Cliffs formed by the Huntley Mountain and Catskill formations are visible north of the park at Barbour Rock. The lowest and oldest layer is the Lock Haven Formation, which is gray to green-brown siltstone and shale over 400 million years old. It forms the base of the gorge, contains marine fossils, and is up to 600 feet (180 m) thick.
Source Credits:
Wikipedia; Owlett, Steven E. (1993). "Of Brachiopods and Glaciers", Seasons Along The Tiadaghton: An Environmental History of the Pine Creek Gorge, Van Diver, Bradford B. (1990). Roadside Geology of Pennsylvania. Missoula, Montana: Mountain Press Publishing Company, Berg, T. M. (1981). "Atlas of Preliminary Geologic Quadrangle Maps of Pennsylvania: Tiadaghton" (PDF). Pennsylvania Department of Conservation and Natural Resources, Bureau of Topographic and Geologic Survey. "Map 67: Tabloid Edition Explanation" (PDF). Pennsylvania Department of Conservation and Natural Resources, Bureau of Topographic and Geologic Survey.
