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