Debris cone
A debris cone consists of debris deposited in a conical shape with a surface slope greater than 10 degrees (perpendicular to contours), usually transported by small streams or snow avalanches.
A debris cone is commonly made when rock from a high-up narrow slit or gorge falls into a flat-floored valley. Here the soil and loose materials are deposited, leaving a mound of conical shape. While an alluvial fan is formed when flowing water rushes rock and soil down a slope, debris cones come from one of several dry processes known as mass wasting. That is gravity pulling loose materials downslope. Such mounds can reach sizes large enough to obstruct river channels. Similar deposits can also be found lying on boulders moved by a landslide, or on a glacier, where a cone-shaped mound of ice or snow may be covered with a veneer of debris thick enough to prevent the underlying ice from melting.
Alluvial fan
An alluvial fan is a fan- or cone-shaped deposit of sediment crossed and built up by streams. If a fan is built up by debris flows it is properly called a debris cone. These flows come from a single point source at the apex of the fan, and over time move to occupy many positions on the fan surface. Fans are typically found where a canyon draining from mountainous terrain emerges out onto a flatter plain, and especially along fault-bounded mountain fronts. A convergence of neighboring alluvial fans into a single apron of deposits against a slope is called a bajada, or compound alluvial fan.
**Logging requirements**
DO NOT POST ANSWERS IN YOUR LOG.
Send the following answers to me via email.
- The text "GC556R9 Debris Cone" on the first line
- With an elevation at the top of 1127 and an elevation at the bottom of 990 feet what level of elevation are you at?
- What color is the major part of the debris at the debris cone?
- There is a cedar tree on top of the cliff at waypoint “sign” trees help hold soil in place. There is a sign right next to the cedar tree. What direction has erosion made it point towards?
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