Midterm #2 MC

Cavern Excavation

-EROSIONAL -Rainwater infiltrates soil, become slightly acidic -travels underground joints, weathering limestone by carbonation -dissolved minerals carried away by flowing water -leaves voids, which get larger --> caverns

Rectangular drainage pattern

Flow along faulted LANDSCAPE and jointed surface Especially karst landscapes Tributary angles 90 degrees

Annular drainage pattern

Form at geologic domes Concentric rings of connected streams

A tributary that is unable to join the main channel on a floodplain due to natural levees is called?

Yazoo tributary

ventifacts

a stone shaped by the erosive action of windblown sand

The grinding and shaping of rocks surfaces by the "sand blasting" action of particles captured in the air is termed

abrasion

Karst topography is formed primarily by

carbonation and solution

Stream drainage patterns are determined by which of the following?

climate, regional steepness and relief and variations in rock resistance

The removal and lifting of individual loose particles by the wind is termed?

deflation

What drainage pattern is tree-like and efficiently moves water and sediment through its system due to minimization of the total length of each branch?

dendritic

What drainage pattern has no clear geometry and no true stream, valley, this drainage pattern occurs in areas such as glaciated shield regions?

deranged

The area of land from which all water in it drains to the same is known as?

drainage basin

If material is to move downslope, it must overcome the force of?

friction, cohesion of the material and inertial resistance

The fact that water expands as much as 9% of its volume as it freezes is the basis of?

frost wedging

Chemical weathering is greatest under conditions of

higher rainfall and temperatures

Interfluve

highest point of joining valleys

A basin in which water leaves via evapotranspiration or subsurface gravitational flow instead of reaching the ocean is said to have?

internal drainage

Alluvial fans are formed where flowing water _____________ as it leaves a constricted channel

loses velocity (velocity slows--> deposition)

Intermittent streams

occur every year or for part of the year

Perennial streams

occur year round

A slow persistent mass movement of surface soil is called?

soil creep

In polar and alpine regions, thawing and saturation of the upper layer of soil resulting in a slow downslope movement is called

solifluction

Which of the following does not favour delta formation?

strong ocean currents What does: -shallow ocean water along the coast -a lack of lakes or reservoirs upstream -a large sediment load

Hydration involves

the addition of water with little chemical change

Hydrolysis involves

the chemical reaction with water

Plants are important to the development of karst primarily because?

they supply organic acids that enhance the dissolution process

Which of the following is NOT an example of a speleothem?

uvala -stalagmite, stalactite and soda straw ARE

Which of the following lists of processes are in the correct sequence as to their occurrence in nature?

weathering, erosion, transport, deposition

Elongated, streamlined ridges aligned parallel to the most effective wind direction are called

yardangs

Cavern Decoration

DEPOSITIONAL -mineral-rich water flows along surfaces inside caves -water evaporates, allowing chemical precipitation--> limestone forms -very slow growth of speleothems --> one layer at a time

________________________ streams are not connected to groundwater systems and only flow after precipitation events

Ephemeral

The presence of talus slopes indicates that _______ occur

rockfalls

Which of the following can lead to the slope failure that causes mass movement?

saturation, oversteepening of slopes, earthquakes and volcanic eruptions

Maximum velocity in a meandering stream occurs?

At the outer portion of the meander curve (cutbank)

Which of the following is incorrect regarding floodplains?

-they are characterized by rapids and low waterfalls They are -formed by recurrent flooding in the area adjacent to the stream -natural levees on either side of a stream are formed during times when the stream is at flood stage and overflows the bank -generally in low-lying areas

The maximum angle at which soil, sediment and rock will remain without moving downslope (stable slope) is called the?

Angle of repose

trellis drainage pattern

Network of long, parallel streams Tributary angles near 90° Form where alternating bands of hard and soft strata

What drainage pattern results when streams flow off a central peak or dome?

Radial pattern

Which of the following is not necessary for well-developed karst to develop?

arid conditions is NOT It needs -high proportion of calcium carbonate in the rock -joints in rock of otherwise low permeability -vegetation

The degradation of a landscape by weathering, erosion and transportation will ultimately reduce the landscape down to?

base level

Bed load is moved by?

both saltation and traction but NOT suspension

Excess sediment may result in which of the following channel patterns?

braided stream

The total possible load a stream can transport is its __________, where as a stream's ability to move particles of specific size is its _______________.

capacity; competence

What drainage pattern is associated with steep slopes?

parallel

Salt-crystal growth (salt weathering) is an example of a ______________ weathering process

physical

Which of the following is incorrectly matched?

point bar--area of substantial erosion

Entrenchment of a channel occurs because?

rejuvenation occurs due to uplift (change in base level)

Factors influencing the weathering process include?

rock composition and structure, climate and vegetation