Welcome to the High Rock overlook. This is one of the best views in the state of Maryland. High Rock is the highest point on the Maryland portion of the Appalachian Trail. The overlook is used for hang gliding, although you will need to first obtain a permit if you want to hang glide.
This area also has Quirauk Mountain, which is the highest point on South Mountain in Maryland. This region of western Maryland is composed largely of folded layers of sandstone, limestone, and other sedimentary rocks. The geological make-up of South Mountain contains quartzite, sandstone, shale, and phyllite.
Quartzite is a hard, non-foliated metamorphic rock which was originally pure quartz sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of iron oxide
Most sandstone is composed of quartz or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any color, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions.
Shales are typically composed of variable amounts of clay minerals and quartz grains and the typical color is gray. Addition of variable amounts of minor constituents alters the color of the rock. Black shale results from the presence of greater than one percent carbonaceous material and indicates a reducing environment. Black shale can also be referred to as black metal. Red, brown and green colors are indicative of ferric oxide (hematite – reds), iron hydroxide (goethite – browns and limonite – yellow), or micaceous minerals (chlorite, biotite and illite – greens).
Phyllite is a type of foliated metamorphic rock created from slate that is further metamorphosed so that very fine grained white mica achieves a preferred orientation. It is primarily composed of quartz, sericite mica, and chlorite. Phyllite has fine-grained mica flakes in a preferred orientation, whereas slate has extremely fine clay flakes that achieve a preferred orientation, and schist has large flakes in a preferred orientation. Among foliated metamorphic rocks, it represents a gradation in the degree of metamorphism between slate and schist. The minute crystals of graphite, sericite, or chlorite, or the translucent fine-grained white mica, impart a silky, sometimes golden sheen to the surfaces of cleavage, called "phyllitic luster".
Please do not post any spoiler photos or information in your log. In order to get credit for this Earthcache, please email me the answers to the following questions:
1. What is the elevation at the given coordinates?
2. What state(s) can be seen from the vantage point?
3. Find a non-grafitti area of rock. You may have to explore the lower side of the lookout via the trails. What two types of rock are highly visible here at High Rock? Describe why you think it is those two types. Use color and texture in your explanation.
4. REQUIRED: post a picture of yourself or personal item on High Rock. Please upload your photo(s) with your "found it" log.
Be sure to e-mail me within 7 days of logging the cache to get credit for your work. I will only contact you if there are issues with your answers. If the rules of finding an Earthcache and e-mailing the owner is not followed your log will be deleted without notice.