Rock On! EarthCache
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This Earthcache lies in that East Coast Gulf Coastal Plain section of Alabama. The Coastal Plain is one of five physiographic sections of Alabama. It developed on geologically young Mesozoic to Recent (about 140 million years ago to the present) sedimentary rocks. The rocks are mainly chalk, sandstone, limestone and claystone. The primary rock resources of the Coastal Plain are the layers of sediment eroded during the Cretaceous, Tertiary and Quaternary Periods from the Appalachian Mountains. Millions of years ago this area of Alabama was covered in ocean. As the Appalachians were eroded by rain, wind, running water and freeze/thaw cycles, bits of rock and sand were carried by streams and rivers flowing into the ocean. These bits of rock and sand formed sediment and over time were layered on the bottom of the then ocean. Over time these sediments, along with plants and animals, became cemented together forming what is known as sedimentary rock. It is in these rocks where fossils can be found and in areas of heavy deposits fossil fuels can be located. There are six main types of sedimentary rocks depending on the appearance of the rock.
Sandstone is a soft stone that is made when grains of sand are cemented together. Sometimes the sandstone is deposited in layers of different colored sand. Sandstone has a sandy texture.
Conglomerate rock has rounded rocks (pebbles, boulders) cemented together in a matrix.
Shale is clay that is hardened and tuned into rock. It often breaks apart in large flat sections. Shale is usually very smooth.
Limestone is a rock that contains many fossils and is made of calcium carbonate and/or microscopic shells. If vinegar or other mild acid is applied to limestone the acid will fizzle as it reacts with the carbonate. Areas with a lot of limestone contain karst features, such as caves. As acidic water slowly dissolves the rock away over time, cavities, and eventually caves may form.
Gypsum is a sedimentary mineral that forms when sea water evaporates.
Breccia has jagged bits of rock cemented together in a matrix.
Sedimentary rocks of this regions have econmic uses and also make up the 20 major aquifers found in Alabama. The sediments left behind in this region provide fertile soils which is important to the areas agriculture.
Much of the sediment found in the Coastal Plain is relatively young and hasn’t formed rock yet. This younger sediment dominates the region and covers the underlying sedimentary rock. For this reason the Coastal Plain has few solid rock resources at or near the surface.
Sources: Encyclopedia of Alabama, Rock Resources of the Coastal Plain
At the coordinates listed above there is an example of Coastal Plain sedimentary rock that is exposed at the surface. This rock outcrop is located along the Bartram Trail in the Tuskegee National Forest. To receive credit for this Earthcache please email me the answers to the following questions
1. What type of sedimentary rock do you think this rock is?
2. There is a very large rock at this location. At its highest point estimate the height of the rock?
3. Do you see any fossils among the rock outcrop?
Optional- feel free to post pictures of your visit to this site. 
Additional Hints
(Decrypt)
Gb erprvir perqvg sbe guvf Rnegupnpur cyrnfr rznvy zr gur nafjref gb gur sbyybjvat dhrfgvbaf
1. Jung glcr bs frqvzragnel ebpx qb lbh guvax guvf ebpx vf?
2. Gurer vf n irel ynetr ebpx ng guvf ybpngvba. Ng vgf uvturfg cbvag rfgvzngr gur urvtug bs gur ebpx?
3. Qb lbh frr nal sbffvyf nzbat gur ebpx bhgpebc? Bcgvbany- srry serr gb cbfg cvpgherf bs lbhe ivfvg gb guvf fvgr.