A Fall Line (or Fall Zone) is a narrow zone of transition between the Piedmont and the Coastal Plain and is so named because it marks the last appearance of bedrock waterfalls in river channels along the Atlantic Coast. Upstream from this point, river channels are rocky and straighter, with abundant rapids. Below the fall line, rivers tend to open up and bend gently back and forth as they flow over the coastal plain. From a geological perspective, it represents the contact between outcrops of crystalline Piedmont rocks (like granite) and the sedimentary deposits of the Coastal Plain.
In the United States, the fall line occurs between the Piedmont (the foothills of the Appalachian Mountains) and the Coastal Plain. The line stretches from New Jersey south along the coast to southeast Alabama, in some areas appearing as a cliff or escarpment, in other areas not as pronounced. The fall line is the ancient shoreline of the Atlantic Ocean (Mesozoic era -- the Age of Dinosaurs). It separates Upper Coastal Plain sedimentary rocks to the south from Piedmont crystalline rocks to the north.
Here is a map view look at the Fall Zone, as it stretches parallel to the east coast dividing Piedmont from Coastal Plain. Notice that the Fall Zone runs right through the major cities of Atlanta, Richmond, Fredericksburg, Washington, Baltimore, Philadelphia, and New York. Why? Because these cities were all settled at the furthest-upstream navigable point on their respective river systems. Beyond the Fall Zone, boats start running into hard Piedmont rocks sticking up from the bottom of the river.
A fall line is typically prominent when crossed by a river, for there will often be rapids or waterfalls. Many times a fall line will recede upstream as the river cuts out the uphill dense material, often forming c-shaped waterfalls while in others it is a zone that may be many miles wide.
To log this cache you must answer the following questions–
#1 – What is the approximate elevation of the river at this location.
You must take into account that you are above the river.
#2 – How many feet does the Savannah River drop over the whole Fall Line Zone?
#3 – How long is the Savannah Fall Line Zone? (In miles)
Please email all answers to the Cache Owner's Profile Email. Do not post them in your logs even if encrypted. You may also include a picture of yourself holding your GPS at the posted coords but it is not required.
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