Chapter 16
Usually 4th order streams are more numerous than 1st order streams.
False
The land separating adjoining valleys is known as a(n) ________.
Interfluve
fluvial processes
processes that involve water
Alluvium
general term for stream deposited sediment
A drop in sea level or a tectonic uplift of the land surface causes stream ________.
rejuvenation
In the system of stream orders, the smallest unit in the network is at the ________.
1st order
The final result of the classical theory of the geomorphic cycle concept is ________.
A peneplain
Drainage basin or watershed
All area that contributes to overland flow, streamflow, and groundwater
An imaginary surface extending beneath the continents which limits how deep streams may cut is ________.
Base level
The elevation limit of a stream downcutting on a land mass is called ________.
Base level
This drainage pattern looks like the veins on the underside of a leaf:
Dendritic
________ drainage patterns are more numerous tan all other drainage patterns combined.
Dendritic
The total volume of flow in streams is termed ________.
Discharge
Branching channels that cross a delta are known as ________.
Distributaries
When a meandering stream is incised into a gradually rising crust or bedrock the result is a(n) ________.
Entrenched meander
Aggradation occurs on geologically uplifted parts of Earth's crust.
False
Friction has little impact on the energy of water moving down a channel.
False
Most of a stream's transported material is classified as bedload.
False
Streams flowing into a structural basin form radial drainage patterns.
False
The world's largest streams are intermittent.
False
The most prominent of all depositional landscapes is the ________.
Floodplain
Streams which flow for only a part of the year are ________.
Intermittent
A flat alluvium-floored valley with fairly steep walls and a stream beginning to meander would be in the ________ stage of the erosion cycle.
mature
Three components of stream load
1. Dissolved load, material dissolved into a solution 2. Suspended load, small rock particles that are carried along without touching the bottom of the stream bed 3. Bedload, is larger rock fragments which may bounce or drag along the bottom of the stream bed
A typical drainage pattern on conic volcanic mountains would be ________.
Radial
The process in which small particles are moved along by streamflow or wind in a series of jumps or bounces is ________.
Saltation
The direct collision of a raindrop with the ground, laterally shifting fine particles a few millimeters, is ________.
Splash erosion
Competence verses capacity
Stream competence is the size of particle that can be transported in a stream. Stream capacity is the amount of stream load that can be carried.
Drainage devide
The point where a drainage basin ends
Drainage patterns are most commonly a response to geologic structure.
True
Knickpoints are irregularities in otherwise graded channel profiles.
True
Rejuvenation results from the uplift of a regional landscape and creates new slope angles to be weathered.
True
Streams carving large valleys do most of their erosional work during flood stage.
True
Rivers downcutting into a land surface, in the absence of other forces, usually tend to erode a ________-shaped form.
V
Surface indicators of turbulence in stream flows include eddies and ________.
Whirlpools
A steep walled defile with a V-shaped profile and narrow valley floor would, according to the geomorphic cycle, be in the ________ stage.
Youthful
The natural levees on floodplains along large rivers merge outwardly and almost imperceptibly with the less well drained and lower portions of the floodplain, generally referred to as the ________.
backswamps
Sea level is the ________ or lower limit of stream downcutting.
base level
Stream orders
first order streams are the smallest and have no tributaries
In terms of erosion, a gulley is a larger example of a feature called a(n) ________.
rill
The greatest amount of material transported by a stream is carried in its ________.
suspended load
A tributary which is prevented by a natural levee from entering the main stream and runs for a considerable distance parallel to the main stream before finding an entrance is known as a(n) ________ stream.
yazoo