lol geo april/11

Question 1

What is mass movement?

Answer 1

downslope of movement of rock, regolith, and soil bc of gravity, the most dramatic occur in rugged geologically young elevations

Question 2

what triggers a mass movement?

Answer 2

Saturation with water- water fills pore space and reduces the cohesion & makes it heavier so it falls

steep slopes- cut toes & steeper angles increase gravities effect

removing vegetation- roots tie soil together

earthquake vibrations

Question 3

What is a “fall”

Answer 3

Free fall of individual pieces of any size

Question 4

What is a slide?

Answer 4

When a big chunk of material slides down in one piece, usually dry material

Question 5

What is a slump?

Answer 5

When it falls off in layers, leaves noticeable scars, slow and common in clays

Question 6

What is a creep?

Answer 6

Very gradual movement of surface soil, shows in the buildings or bent trees bc of the freeze n thaw/wetting and drying

Question 7

What is a debris flow

Answer 7

Downslope flow after a lot of water saturates the soil

Question 8

What is a lahar

Answer 8

Debris flow of the slope of a volcano, saturated with water

Question 9

what is solifluction

Answer 9

soil flow, slow flow of water common to permafrost regions,

Question 10

What is transpiration?

Answer 10

Release of water from plants

Question 11

What determines how much water infiltrates versus how much absorbs

Answer 11

intensity & duration of rainfall
surface material
slope
type and amount of vegetation

Question 12

What are rills

Answer 12

when sheet flow of water turns into tiny channels

Question 13

Describe the areas of a river system from top to bottom

Answer 13

Headwaters/ sediment production- sediment starts at bedrock
zone of transportation- trunk streams move sediment
zone of deposition- either accumulate to make a delta or moved offshore

Question 14

Describe the drain patterns

Answer 14

Dendritic- branching like trees, common
Radial- like wheel spokes, down a mountain
rectangular- on faulted bedrock
trellis- parallel patterns on alternating weak and resistant bedrock

Question 15

What does cross-sectional shape of a stream mean

Answer 15

A slice across the channel. CS determines amount of flow in contact with the banks and bed, this is called the wetted perimeter

less w.p=less drag= faster flo

Question 16

Ratios

Answer 16

Increases over distance: discharge, size, velocity
Decreases over distance: slope, roughness, amount of sediments

Question 17

What is quarrying

Answer 17

removing blocks from the bed of a stream channel

Question 18

How can sediment be transported?

Answer 18

Dissolved load- carries sediment, invisible, flows with the stream
Suspended load- greatest amt carried, visible, fine
Bed load- move through saltation, coarse materials

Question 19

Capacity and competence

Answer 19

Capacity- max load of particles a stream can transport in a certain amt of time
Competence- measure of what size particle a stream can move

Question 20

Bedrock channel vs alluvial channel

Answer 20

Bedrock-stream cutting into solid rock, like white water rafting
alluvial-a stream w a floodplain, change constantly

Question 21

cut bank and point bar

Answer 21

A cut bank is on the outside and point bae is on the inside

Question 22

Base level

Answer 22

Lowest elevation a stream can erode its channel. where the mouth enters

Question 23

What makes a v-shaped valley

Answer 23

Fast moving water, rapids, waterfalls

Question 24

What is a delta

Answer 24

accumulation of sediment where a stream enters the ocean

Question 25

What is a yazoo tributaries

Answer 25

stream that flows parallel to the main stream because a levee is present

Question 26

What’s the largest reservoir of fresh water?

Answer 26

Groundwater, 30% of our freshwater supply. 96% liquid freshwater

Question 27

What is the zone of soil moisture, saturation

Answer 27

When water is a film on the surface of soil particles and also where all open spaces in sediment and rock filled w water

Question 28

what’s the order of water table stuff

Answer 28

-unsat zone
-water table
-zone of sat

Question 29

gaining and losing streams

Answer 29

gain- recieve water from the gw system
lose- provide water to gw system

Question 30

Hydraulic gradient

Answer 30

water table slope,
h1-h2 over distance

Question 31

What did darcy do?

Answer 31

showed that the velocity of groundwater flow is proportional to the slope of the water table: The steeper the slope, the faster the water moves

Question 32

Whats a perched water table

Answer 32

an aquitard is above the water table

Question 33

What is porosity vs permeability

Answer 33

Porosity is the percent that has pore spaces, permeability is ability to transmit a fluid

Question 34

what is an aquifer vs an aquitard?

Answer 34

aquifer allows water flow like sand or gravel, aquitard does not

Question 35

what is hydraulic conductivity

Answer 35

a coefiicient that takes into account the permeability and viscosity of a fluid

Question 36

where does a spring occur

Answer 36

when the water tablr exceeds earths surface

Question 37

compare ice sheets and alpine(valley) glaciers

Answer 37

ice sheets are huge, inhospitable, greenland and Antarctica

alpines are more like a stream of ice flowing down a mountain

Question 38

if accumulation exceeds ablatoon (loss) then,,,

Answer 38

glacial front advances