Frazier Falls -- Glacial Activity EarthCache
Frazier Falls -- Glacial Activity
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
Frazier Falls is located south of Graeagle in the Plumas National Forest at about 6200 ft. The ½ mile trail to the falls overlook is paved, but a bit steep for wheelchairs.
From Highway 89 take Gold Lake Rd. (Road 24) 1.7 miles to the signed turn-off. Drive an additional 4.3 miles to the trailhead.
Water flowing from Gold Lake becomes Frazier Creek, plunges over the escarpment into the canyon below and eventually joins the Middle Fork of the Feather River near Graeagle. Since the falls are fed by snow-melt, they are at their most spectacular through early summer. The falls are a beautiful sight and well worth the effort to reach them for this reason alone. But this walk also provides a graphic lesson in how glaciation has shaped many parts of the Sierra Nevada. Glaciers are formed in areas where more snow falls in winter than melts in summer. As the light, fluffy snow accumulates year on year, it is crystallized and compressed into a solid mass of interlocking ice crystals. When sufficiently thick, often hundreds of feet thick, the inexorable pull of gravity allows the glacier to flow down hill. The great weight of ice slips along the bedrock, its movement aided by melt water which acts as a hydraulic jack as well as a lubricant. This melt water forms in the lower depths of the glacier because of the great pressure of the ice above it. Friction between the ice and bedrock generates heat that also melts some ice. Downhill movement can vary from a few millimeters per day up to several meters per day.
In your walk toward the falls overlook you will see evidence of glacial action. Most notable is the glacial sculpting of the gray-green metamorphosed base rock. Observe how in places the rock appears to have been carved and smoothed into graceful scallops. It is not necessary to do so, but if you leave the trail at the wooden bridge across Frazier Creek and proceed (carefully!) a couple hundred feet downstream to the head of the falls, you will see the best evidence of glacial sculpting. Note how in many places the smoothed rock has actually been polished. You will also see striations in the rocks caused the scraping of the bedrock surface by rocky debris embedded in the bottom of the glacier. These striations indicate the direction of glacial flow.
Erosion of the landscape by glaciers occurs in two ways. As described above, the bedrock may simply be abraded by rocks embedded in the passing glacier. More dramatic erosion occurs when the glacier rips away huge chunks of rock as it passes by. This action has created the stair-stepped appearance of the falls area. You can best see this from the cache coordinates, the falls overlook, as you look toward the falls.
LOGGING THE CACHE
To log this cache you MUST do the following:
E-mail me the answer to the following questions. Do not post your answers in your log.
a. Along what direction did the glacier move?
b. In your walk from the parking lot to the overlook you will have seen many rounded rocks strewn about which are different from the surrounding bedrock. Where did they come from and how did they get there?
Other cachers would enjoy seeing a picture of you at the site or other interesting shot of the area. This is optional.
Additional Hints
(No hints available.)