science weathering and soils unit

Porosity

amount of open space in a rock

Amount of Cement

the more cement between the particles the less pore space

sorting

well sorted soils have more pore space than unsorted soils

fracturing

Bedrock with more fracture or cracks has more pores than bedrock without many cracks

equal volumes of sorted sediment

has equal pore space

Permeability

ability of water to flow through a soil

impermeable

the inability of water to flow

what does permeability depend on?

soil composition

large particles

-More Permeable

-Water flows easily from space to space

small particles

-Less Permeable

-Its hard for water to find a path through the soil

sorted particles

-More Permeable

-Plenty do open spaces that connect to each other

unsorted particles

-Less permeable

• Small particles fill up the spaces leaving little room for water to move

capillarity

the ability of water to rise in small openings

mass movement(gravity)

unsorted/angular

wind causes what type of sorting?

sorted/rounded

waves

sorted/rounded

what are glaciers?

thick masses of ice that form over thousands of years

valley glacier

ice that flows down mountain valleys at high latitudes

ice sheet

ice that covers a large region where the climate is extremely cold

plucking

Frost Action loosens blocks of rock and the glacier then lifts them away

Abrasion

the ice slides over the rocks like sandpaper

striations

scratches left on the bedrock as the glacier moves over it

deposition due to glaciers results in

random arrangement

angular sediments

U-shaped valley

ice carves a wide valley pushing everything in its way

kettle lake

small lake formed when a chunk of ice becomes dislodged and then melts

glacial erretic

large boulders dropped by melting ice

till

unsorted sediments left behind from a glacier

moraine

ridges of till

drumlin

an oval shaped mound of till

erosion

picking up sediment

depositional

putting down sediment

erosion with equal deposition is called

dynamic equalibrium

five major agents of erosion

gravity

wind

waves

glaciers

running water(streams)

What is mass movement(gravity)

the transfer of rock and soil in a downward slope due to gravity

what causes mass movement to happen?

water-heavy rains or melting snow over

saturates the surrounding surface materials with water

deposition due to gravity leaves behind…

unsorted and angular rock fragments

deflation

the lifting or removing of small loose particles

abrasion

wind blown sand blasts exposed rock smoothing and polishing them

wind erosion is more effective in

desert locations(arid=dry)

wet sediment

heavier

dry sediment

easier to pick up

graded bedding

large particles are dropped first then smaller particles

deposition by wind results in

small, sorted particles

waves along the shoreline are constantly

weathering

eroding

and depositing sediment

deposition due to waves is

sorted(large to small) and rounded

time- the more time a rock is exposed

the more weathering will occur

surface area- the more surface area a rock has exposed

the more weathering will occur

a solid rock has the least surface pressure

the interior is protected

a ground up rock has greatest surface area- exposed

the interior can now be attacked

mineral composition

a minerals hardness determines its resistance to weathering

types of climate weathering

physical, chemical

factors that affect weathering

climate and surface area

weathering

the break down of rock at or near earth’s surface

sediments

smaller pieces of rock that have undergone weathering

when does weathering occur in rocks?

when the rocks are exposed to air or water

chemical weathering

the breakdown of rock through a charge in mineral or chemical composition

chemical weathering increases in

warm and moist climates

oxidation(type of chemical weathering)

when iron combines with O² to make rust

another name for water is “blank” because it can resolve almost anything

universal solvent

what does water combine with for form carbonic acid?

CO²

carbonic acid can blank most rocks

dissolve

sinkhole

a natural depression in a land surface formed by the collapse of a cavern roof

physical weathering

the breakdown of rock into smaller pieces without chemical change

abrasion(type of physical weathering)

occurs when rock particles grind against rock

frost action(frost wedging)

weathering process caused by cycles of freezing and thawing of water in rock openings

infiltration

the process which water seeps into soil or rock

plant root growth(root action)

as plants grow they can also spread cracks apart even farther

what happens to rocks when temperatures increase

rocks expand and fracture

humus

part of the soil that serves as a source of plant nutrients

streams erode their channels which does what to loose particles?

lifts loose particles

the stronger the current

the more erosional power it has

capacity

the maximum load a stream can carry

stream deposition

streams deposit sediment in a sorted pattern. largest particles settle out first, smallest particles settle out last

hydrosphere

all water on plant earth

water cycle

the constant movement of water among the oceans, the atmosphere, the solid earth and the biosphere that does not stop or end

evaperation

the process of converting liquid water to a gaseous form in the environment

transpiration

the release of absorbed water by plants into the atmosphere

condensation

water vapor changing back into liquid water clouds are formed by condensation

precipitation

droplets join together until they are too heavy. any form of water that falls from a cloud

infiltration

the movement of surface water into rock or soil through cracks and spaces.

run off

water that does not infiltrate flows over the land into rivers and lakes

saturated

filled to capacity, can’t hold more

unsaturated

not filled, can hold more

permeable

having pores or openings that permit liquids or gases to pass through

impermeable

not permitting passage (as of a liquid)

larger particles drop

first

smaller particles drop

last

maximum velocity occurs on the blank of channel bends

outside

minimum velocity occurs on the blank of bends

inside

straight section

stream bed is symmetrical

highest speed in direct center

left meander

steeper on the left(erosion)

gentle on the right(deposition)

faster in the center of the deepest location

right meander

steeper on the right(Erosion)

gentle on the left(deposition)

faster in the center of the deepest location

deposition occurs as

stream flow decreases

V-shaped Valley

a narrow v-shaped valley shows that a stream primarily cuts down toward the base level

common features are rapids and waterfalls

floodplain

a wide valley is created when a river erodes the banks of its stream channel

this side to side cutting creates a flat valley floor

oxbow lake

most erosion occurs on the outside of the meander

when deposition cuts off these bends an oxbow lake is formed