Science (1st FINAL TERM)

Granular flow

contains low amount of water, 0-20% water

Coastal processes

it has 3 main processes that work in the sea

Saltwater intrusion

is the movement of SALTWATER into underground sources of freshwater

Coastal Transportation

is the movement of material in the sea and along the coast by waves

Erosion

is the wearing away of the land by the sea

coastal erosion

is typically driven by the action of the waves and currents, but also by mass wasting processes on slopes and subsidence

Coastal deposition

is when material that is being transported is dropped by constructive waves

Submersion

is when the sediments is SUBMERSED under water and eventually replaced back to its orginal location

Corrasion/Abrasion

is when the waves pick up beach materials and hurl them at the base of a cliff

Deposition

it happens when swash is stronger than the backswash and is associated with constructive waves and it also created a range of landforms

Quarrying

it is an excavation or pit, usually open to the air

Longshore drift

it provides a link between erosion and deposition

Environmental forces

the one who influences the continuous breakdown, wearing away and loosening of rocks and soils

Slurry flow

water saturated flow which contain 20-40% water

creep

slowest type of mass wasting requiring several year of gradual movement

Climate

where weathering is mostly physical

submarine slumps, submarine debris flow, turbidity current

3 types of subaqueous mass movement

Traction, Saltation, Suspension and solution

4 types of coastal erosion or 4 different ways on how a material moves

Grain flow

-forms in dry or nearly dry granular sediment with air filling the pore spaces such as sand flowing down the dune face

Rock fall and debris fall

-free falling of dislodged bodies of rocks or a mixture of rock, regolith and soil in the case of debris fall

debris avalanche

-some studies suggest the high velocities result from air trapped under the rocks mass creating a cushion of air that reduces friction and allowing it to move as a buoyant sheet

debris avalanche

-very high velocity flows involving huge masses of falling rocks and debris that break up and pulverize an impact -often occurs in very steep mountain ranges

Quick clays

-water-saturated clays that spontaneously liquefies when disturbed

Mechanical Weathering and Chemical Weathering

2 types of Weathering

slurry flow and Granular flow

2 types of sediment flow

Oxidation, Hydrolysis and Dissolution

3 reactions/process of chemical weathering

erosion, transportation and deposition

3 types of coastal processes

Water erosion, Glacial erosion,wind erosion

3 types of erosion

slump, rock fall and debris fall, Rock slide snd debris slide

3 types of slope failire

Solifluction, debris flow and mud flow

3 types of slurry flow

Abrasion

Caused by gravity as a rock tumbles down a mountainside or cliff

Abrasion

Caused by moving water as particles in the water collide and bump against one another

Ice wedging

Common in earth's polar regions and mis-latitudes, and at higher elevations

Climate, Rock type, Rock Structure, Topography and Time

Factors that affect the type, extent and rate at which weathering takes place

Ice wedging, Salt Crystal growth, Abrasion, Biological Activity

Forms of mechanical weathering

Hazard zone mapping, proper land use, engineering mitigation techniques

How landslide hazard can be reduced?

submersion

It can temporarily submerse an island and create island as well

Crystal Growth

It often occurs when groundwater moves into empty pores or spaces of rick by capillary action

Weathering

It simply does not involve any movement of rock material

Time

Longer time of exposure to agents of weathering means higher rate of weathering

Ice wedging

Main form of mechanical weathering in any climate that regularly cycles above and below the freezing point

Abrasion

One rock bumps against another rock

Corrasion, Abrasion, hydraulic action, attrition and corrosion/solution

Processes of coastal erosion

Mechanical Weathering

Rock changes physically without changing its composition

Weathering

Rocks, Minerals, soils normally change their stucture under the action or influence of certain environmental forces

Natural forces and life

The 2 main causes of mechanical weathering

Rock Structure

The presence of cracks where the agents of weathering (water, plant roots, etc) can enter enchances weathering

Mechanical Weathering

The process in which it is physically broken into smaller pieces due to any force (natural) without any alteration

Weathering

The process where rock or soil are dissolved or worn away into smaller and smaller pieces due to particular environmental factors

Rusting

The process whereby the rock minerals lose one or more ions or atoms in the presence of oxygen

Erosion

The transportation of the eroded materials by natural angencies (such as water or wind) from the point of removal

Creep, Earth flow, grain flow, Debris avalanche

Types of granular flow

Mining, quarrying, land pollution, excavation, land use

What are human actions that speed up landslides?

Natural forces

Wind, water, ice and gravity

Weathering

______ is different from erosion

Hydrolysis

a chemical reaction caused by water or change in the composition of minerals when they react with water

Slope failures

a sudden failure of the slope resulting in transport of debris down hill by sliding, rolling, falling, or slumping

Mechanical Weathering

also known as physical weathering

shear strength

all forces resisting movement downslope can be grouped under the term ___?

mass movement

are the important part of the erosional processed whereby mas wasting moves materials from higher to lower elevations

Climate

areas that are cold and dry tend to have slow rated of chemical weathering

Saltation

beach material is bounced along the sea floor

Suspension

beach materials is SUSPENDED and carried by the waves

Mechanical Weathering

break rocks into smaller pieces

Denudation

brodest application of the term ersosion embraces the general wearing down and molding of all landforms on earth's surface

Backwash

carries materials back down the beach at right angles

Abrasion

caused by ice in glaciers which carries many bits and pieces of rock

Abrasion

caused by strong winds carrying pieces of sand which can sandblast surfaces

shoreline retreat

coastal erosion is also known as?

solifluction

common wherever water cant escape from the saturated surface layerby infiltrating to deeper levels

Slope Modification

creating artificially sleep slope

Weathering in geological term

defined as the disintegration of rock influenced by animal and plant life, water, and the atmospheric forces in general

Degradation

denudation is also known as ____?

Humans

digging or blasting into rock to build homes, roads, subways, quarrying stone

dissolution

dissociation of molecules into ions

Undercutting

due to streams eroding banks or surf action UNDERCUTTING a slope

Shocks and Vibrations

earthquakes and minor shocks such as those produced by heavy trucks on the road

land use

examples are construction of road, houses, etc...

Salt Crystal Growth

force exerted by salt crystal that formed as water evaporates from pore spaces or cracks in rocks that can cause the rock to fall apart

water

has the ability to change the angle of responce and can reduce the friction aling a sliding surface

Changes in hydrologic characteristics r

heavy rains lead to water saturated regolith increasing its weight

Mud flow

highly fluid, high velocity mixture of sediment and water

Earth flow

involves fine grained material such as clay and slit an usually associated with heavy rains or snowmely

Weathering

involves no moving agent of transport

Rock slide and debris slide

involves the rapid displacement ofmasses of rock or debris along an inclined surface.

Landslide

is a common term used by many people to describe sudden event in which large quantities of rock and soil plunge down steep slopes

Coastal erosion

is a natural process which occur whenever the transport of material away from the shoreline is not balanced by new material being deposited onto the shoreline

Sea wave erosion

is accomplished primarily by hydraulic pressure

Bayhead beach

is formed between 2 headland

land pollution

is the degradation of earth's land surfaced often cause by human activities and its misuse

Coastal erosion

is the loss of coastal lands due to the net removal of sediments or bedrock from the shoreline

Gravity

is the main immediate agent in mass movement.

Saltwater intrusion

is the most common in coastal region, where the freshwater is displaced by the inland movement of saltwater from the ocean

traction

large materials is rolled along the sea floor

Time

length of exposure to agents of weather determines the degree of weathering of a rock

longshore drift

main process of transportation

Solution

material is dissolved and carried by the water

sediment flow

materials flow downhill mied with water or air

volcanic eruption

may produe large volumed of water from melting of glaciers during eruption It also produces shocks

Erosion

process of removing sediments

Glacial erosion

occurs in 2 prinsipal ways 1) Through the abrasion of surface materials 2) by the quarrying or plucking of rock from the glacier bed

subaqueous mass movement

occurs on slopes in the ocean basins and may also occur as a result of an earthquake

Creep

occurswhen regolith alternately expands and contracts in responce to freezing and thawing

Hazard zone mapping

one of the most important step in hazard mitigation is the production of a landslide hazard map

Rusting

oxidation is also known as?

Topography

physical weathering occurs more quickly on a steep slope than on a gentle one

Biological activity

plants and animals (including humans) as agents of mechanical weathering

Organisms

plants and animals can cause mechanical weathering

Rock Structure

rate of weathering is affected by the presence of joints, folds, faults, bedding planes through wich agents of weathering enter a rock mass

Erosion

removal of surface material from earth's crust, primarly soil and rock debris

Debris flow

results from heavy rains causing soil and regolith to be saturated with water

encroachment

saltwater intrusion is also called as?

turbidity current

sediment moves as a turbulent cloud

Longshore currents

sediments are transprted by the lateral movement of waves after they wash ashore or by shallow-water transport just offshore known as?

submarine debris flows

similar to debris flow on land

submarine slumps

similar to slumps on land

mass wasting

the downslope movement of rock, regolith, and soil under the direct influence of gravity

excavation

the exposure, processing and recording of archaeological remains

Rock Type

the minerals that constitute rocks have different susceptibilities to weathering

dissolution

the most easily observed kind of chemical weathering

Longshore drift

the movement of material along the coast

longshore drift

the movement of materials along the shore by wave action

Erosion

the process by which soil and rock particles are worn away and moved elsewhere by wind, water or ice

Weathering

the process of breakdown of rocks at the earth's surface, either by extreme temperature or rainwater or biological activity

Oxidation

the reaction of rock mineral with oxygen, thus changing the mineral composition of the rock

Bowen's reaction series

the susceptibility of minerals (from high to low) roughly follows the inverse of the order of crystallization of minerals in the ____?

Mining

the use of explosives underground are like mini-earthquake

Chemical weathering

the weakening and subsequent disintegration of rock by chemical reaction

Oxidation or rusting

the wearing away of the rocks is thus sped up by _______ as the resultant oxides are weaker than the original materials

Oxidation, hydrolysis and dissolution

these processes either form or destroy minerals, thus alternating the nature of the rock's mineral composition

Ice wedging

this happens because water expands as it goes from liquid to solid

Olivine

this mineral which crystallizes first is the least resistant

Quartz

this mineral which crystallizes last is the most resistant

Slump

type of slide wherein downward rotation of rock or regolith occurs along a curved surface

Slope failures and sediment flow

types of mass wasting process

Swash

waves moving up the beach, it carries materials up and along the beach

Abrasion

wearing away of rocks by constant collision of loose particles

Changes in slope strength

weathering weakens the rock and leads to slope failure

Slope angle, Role of water, presence of clay and weak materials and structures

what are controlling factors in mass wasting ?

Salt crystal growth

what can cause the break-up of rock materials

Climate change

what can increase saltwater encroachment along coastal regions as sea level rises?

water

what changes the chemical composition and size of minerals in rock, making them less resistant to weathering

Salt crystallization

what is common in drier climates?

Corrosion (solution)

when certain types of cliff erode as a result of weak acids in the sea.

attrition

when waves cause rocks and pebbles to bump into each other and break up

Hydraulic action

when waves hit the base of a cliff air is compressed into cracks, often this causes cliff materials to break away