ALLEGHENY NATIONAL FOREST DISCOVERY SERIES
Each of the earthcaches in this series will take you along roads and trails
to discover the wonders that exist in and around the ANF.
Elk - Forest - McKean - Warren
This discovery series was developed as a heartfelt THANK YOU to all who completed the requirements as requested, and wrote positive logs worth the time to read. Complete 24 ECT caches. Send a list of logs (GL links) via message for verification of requirements. Arrange to meet at Cache Condo to pick up your trackable coin.
EARTHCACHE REQUIREMENTS
Each cacher must send his/her own answers BEFORE logging a find. ... "Geocachers must complete the tasks before they log the EarthCache as found." (4.3. EarthCache logging tasks)
Enjoy the journey (learning adventure) as well as the destination (smiley earned). Remember to take only pictures and leave only footprints. To get credit for this Earthcache, complete the following tasks:
NOTE: Answers via message -and- log signature picture are required to post a find for this cache.
1. MESSAGE …. Walk along the inside perimeter of the Quarry. How many miles (or feet) have you walked to encompass this quarry?
2. MESSAGE …. As shown on the map (Lafayette Township - McKean County – PA), the predominant rock types in this area are sandstone and shale. Which of these rocks makes up the bulk of the quarry rocks?
3. MESSAGE …. Sediment was deposited in layers and compressed into horizontal rock strata. Some of the rocks you see are no longer in complete layers. Explain how these rocks have changed from its original formation to what you now see. The listed vocabulary will help with your explanation.
4. LOG …. Post a picture at or near the coordinates. Post a picture of your discovery opening. These pictures are your log signature. No spoiler pics..
OPTIONAL - Please respect the time and effort involved in finding and creating this earthcache by adding A B C to your log.
A. Discover another rock opening in/around the ANF, Give coordinates. Identify your rock opening and explain your choice. If you found your rock opening at a geocache/earthcache site, give name of the cache and GC number instead of cooordinates.
B. 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.
C. 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 ... prose / story / poem / picture. This is a memorable addition to your log and will make other hearts smile.
THANK YOU LN for travelling and hiking with RT to complete this Earthcache Trail.
THANK YOU NT for sharing this location.
BURIED TREASURE
In most places the bedrock is covered by soil and vegetation. However, in places where this cover is removed, the rocks may be exposed and we are able to view the rocks and the story of their formation. When a river slowly erodes the underlying and surrounding rock, cliffs and caverns are formed. When rocks and minerals are extracted, an open-pit mine called a quarry is formed.
QUARRY
The rocks were removed to provide fill for the construction of the B&O Railroad grade. This is the Railroad you crossed to get to the quarry. You probably walked across rocks quarried from this site. The map shows the types of rocks found within McKean County. The Quarry is located in Lafayette Township. As seen on this map, the predominant rocks are sandstone and shale.
SEDIMENTARY ROCKS
Sedimentary rocks are formed from pieces of other rocks that have been weathered, eroded, deposited, compacted, and cemented, resulting in the formation of rocks. Sedimentary rocks are laid down in layers called beds or strata. The newest layers are above older rock layers, providing the rocks haven’t been folded or faulted.
Sedimentary rocks may contain fossils, because they form at temperatures and pressures that do not destroy the fossil remains. These fossil remains are important in matching rock layers. Differences between successive layers indicate changes to the environment which have occurred over time.
http://www.regentsprep.org/Regents/earthsci/rockcorrelation.htm
OUTCROP – exposure of bedrock
SEDIMENT – pieces of other rocks
WEATHERING – breaking into smaller pieces
EROSION – movement of weathered pieces
DEPOSITION – settling of sediments out of water and air
COMPACTION – weight of accumulated sediments squeezes out the water
CEMENTATION – dissolved minerals fill in the spaces and glue the sediments together
LITHIFICATION – changing of sediments into rocks
PRINCIPLE OF SUPERPOSITION – older rocks are on the bottom
FOLDING – bending of rock layers
FAULTING – breaking of rock layers
FOSSILS – preserved remains of ancient plants and animals
ROCK CORRELATION – comparing rock strata
SANDSTONE (Cemented Sand)
What Does It Look Like? Sandstone is often red to brown, light gray to nearly white. Sometimes it is yellow or green. It usually is composed of rounded grains that are all of the same size; and it is usually medium grained. Some sandstones show slight color variations in layering.
What Minerals Make Up the Rock? Quartz; Sometimes contains: feldspars, mica, glauconite (in green colored sandstone), magnetite, garnet, rutile, ilmenite
How Was It Formed? Quartz sand that is produced by the weathering of other rocks (such as granite, gneiss, and other sandstones) is deposited by rivers, waves, or wind. The sediment may have been a sand bar, an ocean beach, or desert sand dunes. The sand is buried under other sediments, compacted by the weight of those sediments, and cemented by material dissolved in water that seeps through it.
SHALE (Compacted Mud)
What Does It Look Like? Shale may be black, gray, red, brown, dark green, or blue. It is fine grained, so particles usually can not be seen. When moistened, shale usually smells like wet mud.
What Minerals Make Up the Rock? Clay minerals; Sometimes with some quartz sand, pyrite, gypsum
How Was It Formed? Clay sediments settle in quiet lakes, lagoons, bays, or off-shore areas. When buried and compacted the clays become shale.Iron oxides often help to cement the particles together.
SEARCHING FOR ROCK OPENINGS
CAVE - A cave or cavern is a natural void in the ground large enough for a human to enter. Caves are exogene, meaning it is deeper than its opening is wide.
EROSIONAL CAVES - Most caves within the ANF are formed from the erosion of sandstone. Since there is little to no calcitic rock here, you will not find any solutional caves.
TECTONIC CAVES - Formed by a mass movement of the bedrock. The rocks separate along joints or fractures, and are pulled apart mechanically. The resulting cave is usually a high, narrow fissure that has nearly planar walls with matching patterns on opposite sides. Rock cities, a type of tectonic cave, are found within the ANF. "Rock Cities are an example of tectonic caves. "Rock cities develop from flat-lying, massive beds of resistant conglomerate or sandstone exposed on hilltops above much weaker beds of shale or siltstone. Widely spaced vertical fractures called joints outline the blocks. Erosion of the hillslope proceeds more rapidly in the weak beds than in the conglomerate, leaving it overhanging so the blocks eventually tumble. Frost heave and root-pry in the joints aid in the process, particularly in the early stages of separation. In time, some buildings may creep far from their source."
TALUS CAVES - Talus caves are formed between boulders that have naturally fallen into a random heap. They are usually small in size.
ROCK SHELTER ... aka rockhouse, crepuscular cave, bluff shelter, or abri. Rock shelters are produced when the bedrock erosion takes place in insoluble rocks. Rock Shelters within the ANF are formed where the resistant sandstone overlies the relatively erosion-susceptible shale. Weathering by a stream might wear away the shale leaving behind a rock shelter with a sandstone roof. Shelters are endogene, meaning the opening is wider than its depth.
CAVITY - These are openings in rocks that are homes to a variety of small animals, but too small for humans to enter.
CREVICE - Long, tight space varying in size from large to small. Because it is usually hard to reach, it is a great hiding place for creatures such as reptiles and insects..
FISSURE - A crack in rock along which there is a distinct separation.
FRACTURE - Any separation that divides the rock into two or more pieces.
RESOURCES
www.dcnr.state.pa.us/topogeo/groundwater/pdfs/mckean.pdf
http://www.minsocam.org/msa/collectors_corner/id/rock_key.htm#Key
http://www.stonestructures.org/html/quarry_types.html