Erosion

These happen on or near the Earth’s surface

Exogenic processes

Erosion caused by outside forces like _________

Sunlight

Erosion can be manifested through _______, ______, and ________

weathering, erosion and transport, deposition

processes that break down and move parts of the land

Exogenic Processes

is the on-site breakdown of rock and its eventual transformation into sediments.

Weathering

2 types of weathering

1. mechanical/physical

2. chemical

is the physical breakdown of a rock into unconnected grains or chunks without changing its composition.

Mechanical or physical weathering

what are the 6 types of mechanical or physical weathering

1. exfoliation

2. frost wedging

3. salt wedging

4. root wedging 

5. thermal expansion

6. human activities

happens when rocks that were once buried deep underground are exposed at the surface

exfoliation

in exfoliation, as the pressure released, the out layer of rock _______ or ________ in sheets —- like an onion shedding its layer

peel off or crack off in sheets

Exfoliation happens in large rocks such as ______

granite

Exfoliation is caused by changes in _____ and ____

temperature and pressure

Process of how exfoliation works where rocks like granite form deep underground

Deep burial and high pressure

Process of how exfoliation works where over long periods, erosion and geological processes (uplift) remove the overburden, bringing these rocks closer to the surface.

Erosion and Uplift

Process of how exfoliation works where the rock expands as it becomes less confined, causing cracks, to form parallel to the surface

Expansion and cracking

what do you call to the cracks in expansion and cracking

exfoliation joints

These cracks allow outer layers or sheets of rock to break off and detach from the main body of rock

Sheet removal

In temperate regions or high-altitude regions, water inside the fractures of rocks experience regular freezing and thawing.

Frost wedging

In frost wedging, when the rock freezes, it causes the joints to _____ and _____, causing pieces of rocks to detach.

expand and grow

Frost wedging process where when liquid water seeps into existing cracks and pores in a rock

Water infiltration

Frost wedging process where when temperatures drop below freezing, the water within the cracks turns to ice

Freezing

In frost wedging process expansion, water expands by about __% in volume as it freezes exerting significant pressure up to ________psi against the rock

expands by about 9% and exerting significant pressure up to 30,000psi

Frost wedging process where pressure forces the cracks to widen and deepen

crack widening

Frost wedging process where when temperatures rise above freezing, the ice melts, and the water seeps further into the now-enlarged cracks

Thawing

Frost wedging process where the cycle of freezing and thawing repeats, causing the cracks to progressively grow larger

Repetition

Frost wedging process where repeated stress from the expanding ice can cause a piece of the rock to be wedged off.

Rock breakdown

It is a form of biological physical weathering where plant roots grow into cracks in rocks, expanding them as the roots enlarge and exert pressure, similar to how ice expands in frost wedging.

root wedging

It is a type of physical (mechanical) weathering where salt crystals grow within cracks and pores in rocks, exerting pressure that weakens and breaks the rock.

salt wedging

It occurs when _________seeps into a rock, then evaporates on a hot, sunny day, causing the dissolved salt to precipitate and expand

salt-rich water

is a type of physical weathering that breaks down rocks through repeated cycles of heating and cooling, which causes the rock to expand and contract at different rates

Thermal expansion

In thermal expansion, the differential expansion and contraction generates ______, creating and widening cracks over time until the rock eventually breaks apart.

stress

What human activities contribute significantly to physical weathering?

Digging and Blasting

occurs when there are chemical changes in at least some of the composition of the rock

Chemical weathering

it is a surface or near-surface process that is not influenced by high temperature or pressure

chemical weathering

occur at a faster rate in warm, wet climates such as the tropics

chemical weathering

This process happens when certain minerals dissolve in water

dissolution

dissolves quickly in plain water, just like how table salt disappears when mixed with water

Halite (NaCl or Rock salt)

dissolves more rapidly in acidic water, such as rainwater (which naturally contains a little acid from dissolved carbon dioxide)

Calcite (CaCO3)

Why do limestones slowly dissolves when exposed to rainwater that creates large underground spaces—caves and caverns

because limestones contains calcite

Dissolution is like rocks_______ in water, just as sugar or salt melts in a glass of water

melting away

this process happens when water reacts with minerals in rocks and breaks them down into new, softer substances

hydrolysis

In hydrolysis, the reaction happens faster when the water is ________

slightly acidic

Hydrolysis is like ___________ of rocks —hard minerals turn into soft clay when they mix with water.

chemical makeover

happens when oxygen reacts with minerals in rocks

oxidation

when oxygen reacts with minerals in rocks, it forms new substances called _______

oxides

gives rocks a reddish or rusty color

iron oxide (hematite)

another rust-like mineral

iron hydroxide (goethite)

weakens the rock and changes its color

oxidation

oxidation is like _________

rock rusting

happens when water is absorbed into the mineral itself.

hydration

Hydration is like a ______—when it soaks up water, it swells.

sponge

This type of weathering happens when living things help break down rocks

biological weathering

In biological weathering, living things act like tiny ___________

rock-breakers

It occurs more faster in places with high temperature and heavy rainfall than in cold and dry ones

chemical weathering

it occurs more frequently in steep slopes than on gentle ones

physical/mechanical weathering

Rocks with minerals that crystallizes and with cracks or slits are more _____ than the one without

fragile

The ________ the time of exposure, to the agents of weathering, the higher and faster rate of weathering

longer

is the process where rocks and soil are moved from one place to another by natural forces such as wind, water, ice, or gravity

erosion

erosion may be affected as ___, ___, ___, and _____

wind, glacier, tide, gravity

commonly occurs in flat, bare areas or dry, sandy, and loose soils.

wind erosion

It detaches soil particles and transports them by wind

wind erosion

are common phenomenon in deserts that transports lots of sediments for hundreds of kilometers

sandstorms

wind erosion doesn’t just move soil—it damages the land, reduces plant growth, and harms the environment by taking away the _______ that life depends on

fertile soil

It causes loss of soil, makes the ground dry and less fertile, damages the soil’s structure, and can even pollute the air when dust is blown away

wind erosion

The sand dunes in ___________ are formed through wind erosion

Paoay, Ilocos Norte

is a huge, thick mass of ice that stays frozen all year long

glacier

made mostly from snow that has been pressed and turned into ice over time

glacier

are very large and heavy, and they seem stationary when you look at them — but in reality, they do move, just very slowly

glacier

as the glacier moves, it carries ____ and drops them when it melts

rocks

this erosion process is _____ in polar regions and in high-altitude mountains

dominant

It is the most common erosion agent.

water

water moves sediments in four ways: _____, _____, _____, and _____

traction, saltation, suspension, and solution

a type of erosion and transport process where large rocks and pebbles are rolled or dragged along the riverbed by moving water

Traction

is a process where small rocks, sand, or pebbles are lifted off the ground by moving water or wind and then bounce or hop along the surface

saltation

happens when very light materials like fine sand, silt, or clay are carried and kept floating in water or air

suspension

happens when certain minerals in rocks dissolve in water and are carried away in the water as it flows

solution

In _________, materials are invisible because they’re completely dissolved

solution

It is the is the downslope movement of rock, soil, and ice due to gravity.

mass wasting

it is also a natural hazard that can cause damage to life and property.

mass wasting

what are the 3 factors that contribute to the occurrence of mass wasting

relief, slope stability, fragmentation and weathering

It refers to the shape and steepness of the land’s surface

Relief

It refers on how flat or sloped an area is

Relief

Why do relief is an important factor in mass wasting?

Because it affects how easily a materials move

It is where gravity pulls harder

steep slopes

On _______ mass wasting happens more faster and more often

steep slope

the pull of gravity is weaker

gentle slope

On ______, the movement is slower or less likely

gentle slope

It refers on how well a slope can stay in place without collapsing or sliding down

slope stability

the pull of gravity that tries to make rocks and soil move downhill

downslope force

the friction and strength of the materials that hold the slope in place

resisting force

mass wasting ca be classified in a number of ways such as ________, _________, and _______

type of material, type of motion, and speed of movement

types of material include _____ and _____

rock and soil

Predominantly coarse soil materials are called __________

debris

predominantly fine materials are labeled as

earth

what are the general types of motion?

fall, topple, slide, spread, flow

includes the free-fall movement, bouncing, and rolling of materials on a slope.

fall

happens when a block of rock or soil tips forward and falls down a slope

topple

happens when a mass of rock, soil, or debris moves downhill together along a clear, smooth surface

slide

what do you call to the clear, smooth surface

sliding surface

the moving material stays together and slides down like it’s gliding on a slippery slope.

slide