This Earthcache will take you down a couple back roads in Barbour County, following the Tygart River. The easiest entrance is via Arden Road from Rt 119. You will need to park along the side of the gravel road, but there is not a lot of traffic in this area, so it shouldn't be a problem.
Since this is an earthcache, there is NO physical container, and thus logging requirements MUST be met to accomplish this cache. For more information about earthcaching, visit earthcache.org.
West Virginia is divided into five physiographic provinces: Appalachian Plateau, Allegheny Mountain Section, Valley & Ridge, Great Valley, and Blue Ridge. The Appalachian Plateau Province covers the western two-thirds of the State where the rock formations are relatively flat, except for several distinct folds and faults on the eastern side of the Province. The oldest rocks are located in these eastern fold sequences and range in age from late Ordovician up through the Mississippian. The majority of the Appalachian Plateau is comprised of Pennsylvanian and Permian strata and is where all the minable coal is located. The rocks exposed in the northern part of the Plateau are younger than those exposed in the southern part. The boundary between the two provinces, the Allegheny Front, is a complex and rather abrupt change in the topography, stratigraphy, and structure. This boundary extends southwestward across the eastern part of the State, passes through Virginia, and reenters the State in the southeast in Monroe County.
Rock Formations
Most of the rocks in West Virginia are sedimentary, deposited during the Paleozoic Era (600 to 230 million years ago); very few igneous or metamorphic rocks occur in the State. The geologic history of West Virginia prior to one billion years ago is poorly understood. The oldest exposed rock in the State is the Catoctin Greenstone, a metamorphosed lava deposited 800 million years ago. Later, a marine sea covered most of West Virginia and deposited marine limestones, shales, siltstones, and sandstones during the Cambrian and Ordovician periods.
Movements of the earth's tectonic plates cause episodes of mountain building which, with subsequent erosion and production of sediments, can have major effects of the geologic history of an area. The first of these mountain-building episodes to affect West Virginia, the Taconic Orogeny, formed mountains to the east of the State that were a source of sediments during the Ordovician, Silurian, and early Devonian periods. Clastics and carbonates were deposited with clastics predominating in the eastern part of the State. Also, non-marine deposition took place and evaporites were deposited in the northern part of West Virginia in the late Silurian.
Highlands to the northeast, formed in the Acadian Orogeny, were the source of clastic sediments in the Middle and Late Devonian. The sea regressed to the west at the end of the Devonian, and continental red beds were deposited over most of the State. The sea covered West Virginia again in the Middle Mississippian (about 330 million years ago). During this time, the Greenbrier Group, composed mainly of limestone, was deposited. The sea retreated again near the end of the Mississippian, and during the Pennsylvanian, West Virginia was low-lying and swampy. During this period, thousands of feet of non-marine sandstone, shale, and coal were deposited.
During the Permian Period, the Appalachian Orogeny began, which was the dominant geologic event in the formation of the Appalachian Mountains. Much folding and thrust-faulting occurred, especially in the eastern part of the State. Erosion became the predominant geological processes.
Rock Folds
Geological folds are the curvatures in rocks or strata containing them. Most visible stratified rocks are located in the rivers, quarries or coasts were, originally, sediment layers deposited in horizontal or near horizontal beds. However, when we observe today they are not only solidified but usually inclined in one direction or another.
Sometimes when the layers come to the surface, you can see a bow or climb to descend into a breast. The folds are measured in terms of wavelength (peak to peak or breast to breast) and height (peak-to-trough). They may be microscopic or have lengths of kilometers.
They can be classified according to various factors independently.
Erosion
Erosion is the process by which the surface of the Earth gets worn down. Erosion can be caused by natural elements such as wind and glacial ice. The key to erosion is something called "fluid flow." Water, air, and even ice are fluids because they tend to flow from one place to another due to the force of gravity. Of the three, liquid water is the most common agent of erosion because there's so much of it on the surface of the Earth. Erosion is often the youngest geological event for a rock formation.
Questions
Looking across the river, you will see a large rock formation that is different from other formations you see along this stretch of river. You can answer all questions from the road and the information above. You do not have to walk to river, and please do not swim in this section of the river! If you post pictures, try not to include the rock formation in your post. You must answer each question on the three parts you observe at this site: geology formations, rock folds, and erosion.
1.1. Based on the information above and this location, about how old is this rock formation?
1.2. Describe the rock formation (color, shape, layers, etc.). How is it different from other rock formations along this road?
1.3. Estimate the length of this formation (in feet).
2.1. Why would this formation be labeled as a geological fold?
2.2. What type of fold is this formation?
3.1. What type of "fluid" has eroded this formation?
3.2. Describe the river today. Include a general description and a description of water near the formation.
3.3. Why do you think erosion is important for why we can observe this formation?
Congrats to Arealwhit and Troopbiz for Co-FTF!!!