Chapter 10 Flashcards
What are the three ways a stream causes erosion?
- Hydraulic action
- Solution
- Abrasion
What is Abrasion erosion?
The grinding sway of rocks by friction and impact during transportation.
What are potholes
Places were water swirled that contained sand and pebbles and caused holes to be worn down into the rock. Similar to the giant hole along leprechaun canyon.
What is a bar?
A sandbar kind of like what’s on the green river.
What is a braided stream
A stream where it has to go through the sand like veins.
What is a meander cut off or an oxbow lake.
When a meandering stream cuts itself of and forms a side lake of sorts. It usually looks like a horseshoe
What are natural levees?
The bank that is built up on either side of the bank of a stream.
What are distributaries?
Small shifting channels that carry water away from the main river. Aka the delta zone were their are meandering streams.
What is Hydraulic Action?
The ability of flowing water to pick up and move rock and sediment.
What are placer deposits?
Were running water has mechanically concentrated heavy sediment.
What is an Alluvial fan?
A large pile of sediment that is deposited from a narrow winding stream as it exits the canyon.
What are the factors involved in the Hydrologic cycle aka the water cycle.
- Evaporation
- Transpiration
- condensation
- precipitation
- Infiltration
- Runoff
What is evaporation?
water evaporating into water vapor.
What is Transpiration?
The loss of water to the atmosphere by plants, providing water vapor to the atmosphere.
What is Condensation?
Water vapor to to droplets and clouds in the atmosphere
Precipitation
Rain
Infiltration
Precipitation that soaks into the soil, becoming ground water
Runoff
Precipitation that flows across the land surface in stream channels or as sheetwash.
what are the three ways sediment can be transported?
- Suspended load
- Dissolved load
- Bed load
What is downcutting?
A valley-deepening process caused by erosion of a streambed.
What is base level
The thoretical limit for erosion of the the earth’s surface.
What is a graded Stream?
A stream that has smoothed its se3lf out and now has a delicate balance between its transporting capacity and the sediment load available to it.
What is lateral erosion?
Erosion and undercutting of stream banks caused by a stream swinging from side to side across its valley floor.
headward erosion
The lengthening of a valley in an uphill direction avoe its original source by gullyin, mass wasting, and sheet erosion.
Stream terraces
Steps on the side of a valley showing where the flood plane used to be.
What are incised meanders
meanders that retain their pattern as they cut vertically downward below the level at which they formed.
What is the recurrence interval
How frequently a river floods.
What are the most common sediment deposits in a flood?
Silt and Clay
What is a Drainage Pattern?
The arrangement in map view of a river and its tributaries.
What are the 4 drainage patterns?
1 Dendritic - resembles the branches of a tree or veins in a leif.
- Radial - A drainage pattern in which streams diverge outward like spokes of a wheel.
- Rectangular - A drainage pattern in which tributaries of a river change direction and join one another at right angles.
- Trellis - A drainage pattern consisting of parallel main streams with short tributaries meeting them at right angles. usually in valleys.
Where do Dendritic patterns form?
Forms on uniformly erodible rock
Where do Radial patterns form?
Hich conical mountains
Where do Rectangular patterns form?
Forms on regularly fractured rock.
Were do Trellis patterns form?
On alternating tilted layers of resistant and nonresistant rock.
