The Appalachian Valley
This area is part of the Appalachian Valley of North Carolina
which is part of the Great Appalachian Valley and is one of the
major landform features of eastern North America. It is a gigantic
trough — a chain of valley lowlands — and the central feature of
the Appalachian Mountain system. The trough stretches about 700
miles from Canada to Alabama and has been an important north-south
route of travel since prehistoric times. These mountains are
characterized by long, even ridges, with long, continuous valleys
in between. From a great enough altitude, they look almost like
corduroy, except that the widths of the valleys are somewhat
variable and ridges sometimes meet in a vee. These curious
formations are the remnants of an ancient fold-and-thrust belt,
west of the mountain core that formed in the Alleghenian orogeny
(Stanley, 421-2). Here, strata have been folded westward, and
forced over massive thrust faults; there is little metamorphism,
and no igneous intrusion.(Stanley, 421-2) The ridges represent the
edges of the erosion-resistant strata, and the valleys portray the
absence of the more erodible strata. Smaller streams have developed
their valleys following the lines of the more easily eroded strata.
The streams can develop waterfalls along the way by eroding the
softer rock quicker such as in this case.
So lets talk about Trash Can
Falls
A waterfall is usually a geological formation resulting from
water, often in the form of a stream, flowing over an
erosion-resistant rock formation that forms a sudden break in
elevation or nickpoint. Some waterfalls form in mountain
environments where the erosive water force is high and stream
courses may be subject to sudden and catastrophic change. In such
cases, the waterfall may not be the end product of many years of
water action over a region, but rather the result of relatively
sudden geological processes such as landslides, faults or volcanic
action.
How Waterfalls are
Formed
Typically a stream or river flows over a large step in the rocks
which may have been formed by a fault line. Over a period of years,
the edges of this shelf will gradually break away and the stream
will retreat upstream, creating a gorge of recession. Often the
rock just below the more resistant shelf will be a softer type,
meaning some undercutting will occur due to the splashback of the
falling water. A shallow cave-like formation known as a rock
shelter or plunge pool under and behind the waterfall will form.
Eventually the outcropping of rock will collapse under pressure to
add blocks of rock to the base of the waterfall. These blocks of
rock are then broken down into smaller boulder as they collide with
each other and they also will continue to erode at the base of the
waterfall by abrasion, creating a deeper plunge pool. Streams will
become wider and more shallow just above waterfall due to the
flowing of the water over the rock shelf and there is usually a
deep pool just below the waterfall because of the kinetic energy of
the water hitting the bottom.
The rock canyon surrounding this waterfall is a direct result of
the above information. Over several thousands of years, Mother
Nature has used this creek to carve out the the Falls that exist
today.
Types of Waterfalls
Block: Water descends from a relatively wide stream or
river.
Cascade: Water descends a series of rock steps.
Cataract: A large waterfall.
Fan: Water spreads horizontally as it descends while remaining
in contact with bedrock.
Horsetail: Descending water maintains some contact with
bedrock.
Plunge: Water descends vertically, losing contact with the
bedrock surface.
Punchbowl: Water descends in a constricted form, then spreads
out in a wider pool.
Segmented: Distinctly separate flows of water form as it
descends.
Tiered: Water drops in a series of distinct steps or falls.
Multi-step: A series of waterfalls one after another of roughly
the same size each with its own sunken plunge pool.
In order to receive credit for this
Earthcache you must do the following....
. Post a picture of you/your group holding your gps in front of
the waterfall with your log. 2. Email the owner with answers to the
following questions. a)Describe what type of waterfall Trash Can
Falls is--this may include more than one of the classifications. b)
Estimate the height of Trash Can Falls. (needs to be within 10
feet) c.)what is the temperature of the water?