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:
1. MESSAGE …. Based on the reading, why are the sides of the bridge straight?
2. MESSAGE …. a. There is a space between bridge and cliff wall. Are you able to stand between bridge and wall? / b. Was the bridge formed predominately by mechanical or chemical weathering. Explain.
3. MESSAGE …. There are large tubes emerging from the edge of the arch. These formed when embedded rock was twisted by the movement of earth’s tectonic plates. ... a. Location of the tubes? / b. What is the average length of the tubes? / c. What is the average diameter of the tubes? / d. What is the composition of the tubes?
4. LOG ... Post a picture at or near the coordinates. This picture is your log signature.
OPTIONAL - Please respect the time and effort involved in creating this earthcache by adding A and B to your log.
A. 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.
B. 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. This is a memorable addition to your log and will make other hearts smile.
Journeys of Heart and Mind ...
Stories to Touch the Heart and Puzzles to Challenge the Mind / Rainbow Tree Story
THANK YOU Chris Perry (Park Manager) and Robert Myers (State Park Naturalist) for permission to share this learning adventure. ... Your permit for the earthcache “Cascade Cave” is 19107CCSRP
THANK YOU Cav Scout, Platinum Earthcache Master for discovering and sharing this location.
THANK YOU LN for helping RT negotiate this challenging terrain
THE TRAIL
Cascade Bridge is on Box Canyon Trail, and is one of the most scenic trails in the park. It is a .75 mile loop trail beginning at the Cascade Caves parking lot, proceeding to the head of Box Canyon, and looping back to the parking area.
THE VALLEY
Most of the valley floor in this canyon is underlain by the Slade Formation. Box Canyon valley is largely a dry bed, because most of the drainage enters the subsurface through the many sinks. Only during major storms would we see any streamflow, You will encounter vertical walls of sandstone known as Carter Caves Sandstone. This sandstone represents a tidal-channel deposit that formed in Late Mississippian time when the area was dominated by extensive tidal currents. The sandstone walls are over 100' thick.
CASCADE BRIDGE
"This structure is not really a bridge or an arch, as it is closed off on one side. This is a collapse alcove that formed by collapse of the sandstone as supporting limestones were dissolved from under the sandstone. This “bridge” or alcove in part reflects the influence of joints in the area. The vertical surface behind the alcove, as well as the flat surface of the sandstone wall defining the head of this valley, are large vertical joints, along which weathering has proceeded."
The sides of this bridge are very straight because the bridge formed between two parallel fractures at the top of the ridge.
WEATHERING
Weathering is the breaking down of rock into smaller fragments. All rock weathers over time. Grains of sediment fall out. Cracks develop on the surface and deep inside. Weathering causes rocks to fracture, buckle, and crumble into soil and sediment. There are two types of weathering - mechanical and chemical.
MECHANICAL WEATHERING breaks apart rocks without changing their chemical composition. Each fragment and particle weathered away by a mechanical process retains the same characteristics as the original rock. Mechanical weathering can be caused by growing plants, flowing/falling water, wind, expanding ice, lightning, and expansion and contraction with heating and cooling. These physical processes create enough force to break rocks into smaller pieces.
CHEMICAL WEATHERING occurs when water, air, and other substances react with the minerals in rock. In chemical weathering, the composition of the rock changes.
ROCK TYPES IN THE CANYON
The rocks you will see along the trail are sandstone, shale, and conglomerate.
SANDSTONE (Cemented sand) ... 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.
SHALE (Compacted mud) ... 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.
CONGLOMERATE (Pieces of other rocks) ... Conglomerate looks like a mixture of sand and different sizes of rounded pebbles. The pebbles are the important observation.
RESOURCE - Geology Tour