IGCSE Environmental Management Chapter 1 Notes

(1)

Environmental

Management

(2)

Continental drift

•

• Continental drift

Continental drift

_{is the movement of the}

Earth's continents.

•

• _{This is due to the m}

_{This is due to the m}

_{antles’ movements}

which causes the tectonic plates to move

(3)

•

• Plate tectonics is the scientic theor

Plate tectonics is the scientic theor

that attempts to e!plain the movements

of the Earth's lithosphere that have

formed the landscape features we see

across the glo"e toda.

•

• # denition the word $plate$ in

# denition the word $plate$ in

geologic terms means a large sla" of

solid roc%. $Tectonics$ is a part of the

&ree

% root for $to "uild$

and together

the terms dene how the Earth's surface

is "uilt up of moving

plates.

•

• o "asicall the earth's lithosphere is

o "asicall the earth's lithosphere is

made up of man individual plates ()

ma*or plates and other minor ones+ of

solid roc% that ,oats upon the hot

mantle.

•

• Churning currents in the molten roc%s

Churning currents in the molten roc%s

"elow propel them along li%e a *um"le of

conveor "elts.

- #

#

.

/

T

E

C

T

.

0

1

1 C

C

P

2

2 - T

T

E

'

(4)

3ow tectonic plates move

(5)

(6)

Plate #oundries

Convergent #oundries

4iverg

4ivergent

ent "oundries

"oundries

T

(7)

Conver

Convergent

gent #oundries

#oundries

•

• _{The plates "asicall m6ove to}

_{The plates "asicall m6ove to}

_wards

each other and destruct land

7

7 #asic movement of plates (in convergent "oundrie#asic movement of plates (in convergent "oundrie

s+

7

7 ceanic5continental convergenceceanic5continental convergence

7

7 ceanic5oceanic convergenceceanic5oceanic convergence

7

(8)

1magine these are two plates

(9)

c

ce

ea

an

n c

c55c

co

on

n n

ne

en

n a

a

convergence

8hen an

oceanic plate

pushes into and

su"ducts9 under

a continental

plate6 the

overriding

continental plate

is lifted up and a

mountain range

is created.

(10)

ceanic5oceanic

convergence

8hen two oceanic

plates converge one is

usuall su"ducted

under the other and in

the process a deep

oceanic

trench is

formed.

:or e!ample 5

Marianas Trench

is a

deep trench created

as the result of the

Phillipine Plate

(11)

Continental5continental

convergence

8hen two continents meet 8hen two continents meet head5on6 neither is

head5on6 neither is

su"ducted "ecause the su"ducted "ecause the continental roc%s are continental roc%s are relativel light and6

relativel light and6 li%eli%e two colliding ice"ergs6 two colliding ice"ergs6 resist downward motion. resist downward motion. 1nstead6 the crust tends to 1nstead6 the crust tends to "uc%le and "e pushed

"uc%le and "e pushed upward or sidewas. upward or sidewas. The collision of 1ndia into -sia ;<

The collision of 1ndia into -sia ;< million ears ago caused themillion ears ago caused the Eurasian Plate to crumple up and override the 1ndian Plate.

Eurasian Plate to crumple up and override the 1ndian Plate. -f

-fter the collision6 the ter the collision6 the slow continuous convergence of slow continuous convergence of the twothe two plates over millions of ears pushed up the 3imalaas and the plates over millions of ears pushed up the 3imalaas and the Ti"

(12)

4ivergen

t

#oundries

•

• #asic movement of divergent "oundries#asic movement of divergent "oundries

•

(13)

(14)

4ivergen

t

#oundries

•

• _{-t divergent "oundaries new}_{-t divergent "oundaries new}

crust is created as two or

more plates pull awa from

each other.

•

• ceans are "orn and growceans are "orn and grow

wider where plates diverge

or pull apart.

•

• when a diverging "oundarwhen a diverging "oundar

occurs on land a 'rift'6 or

separation will arise and over

time that mass of land will

"rea% apart into distinct land

masses and the surrounding

water will ll the space

"etween them

(15)

T

ransform

5fault "oundries

•

• _{#asic movement}

_{#asic movement}

•

• _4etailed

_4etailed

_inform

_ation

•

(16)

T

ransform

5fault "oundries

T

ransfor

ransform5:

m5:

ault #oundaries

ault #oundaries are

are where t

where t

wo

plates are sliding hori=ontall past one

another. These are also %nown as transform

"oundaries or more commonl as faults.

Most transform faults are found on the ocean

,oor. The commonl o>set active

spreading ridges6 producing =ig5=ag plate

margins6 and are generall dened "

shallow earth?ua%es.

- few6 however6 occur on land.

(17)

(18)

E!tra

1nformatio

n

The an -ndreas fault =one in California is a transform

fault that connects the East Pacic @ise6 a divergent

"oundar to the south6 with the outh &orda 55 Auan de

:uca 55 E!plorer @idge6 another divergent "oundar to

the north. The an -ndreas is one of the few transform

faults e!posed on land. The an -ndreas fault =one6

which is a"out B6<< %m long and in places tens of

%ilometers wide6 slices through two thirds of the length

of California. -long it6 the Pacic Plate has "een

grinding hori=ontall past the 0orth -merican Plate for

B< million ears6 at an average rate of a"out ; cmDr.

2and on the west side of the fault =one (on the Pacic

Plate+ is moving in a northwesterl direction relative to

the land on the east side of the fault =one (on the

0orth -merican Plate+.

(19)

Earth?ua%es

•

• Though the ocean

Though the ocean

ic plate as a wh

ole

sin%s

smoothl and continuousl into the

su"duction

trench (convergent

movement+6 the deepest part

of the

su"ducting plate "rea%s into smaller

pieces. These smaller pieces "ecome

loc%ed in

place for long periods of time

"efore moving

suddenl and generating

large earth?ua%es.

uch ear

th?ua%es ar

e

often accompanied "

uplift of the land

" as much as a few meters

(20)

•

• epicenter

epicenter

the point on Earth's

surface directl a"ove

the focus point of an

earth?ua%e

•

• focus

focus

the point "elow Earth's

surface where roc%

"rea%s under stress and

causes an earth?ua%e

(occurs at convergent

and transform

"oundaries+

(21)

olcanoes

• • - volcano is a place on the Earth's surface

- volcano is a place on the Earth's surface

(or an other planet's or moon

(or an other planet's or moon's surface+

's surface+

where molten roc%6 gases and proclastic

de"ris erupt through the earth's crust.

olcanoes var ?uite a "it in their

structure 5

structure 5 some are crac%s in the earth's

some are crac%s in the earth's

crust where lava erupts6 and some are

domes6 shields6

or mountain5li%e structur

es

with a crater at the

summit.

•

(22)

5

5 earth?ua%es

earth?ua%es

•

• Earth?ua%es produced " stress changes in solid

Earth?ua%es produced " stress changes in solid

roc%

due to the in*ection or withdrawal of

magma

(molton

roc%+ are called

volcano-tectonic earthquake

s.

7

7 These earth?ua%es can cause land to su"sid These earth?ua%es can cause land to su"side and can producee and can produce

large gro

large ground crac%s. These und crac%s. These earth?ua%es can occur as roc% isearth?ua%es can occur as roc% is

moving to ll in spaces where magma is no longer present.



olcano5tectonic earth?ua%es don't indicate olcano5tectonic earth?ua%es don't indicate that the that the volcanovolcano

will "e erupting "ut can occur at antime.

7

7 The second categor of volcanic earth?ua% The second categor of volcanic earth?ua%es arees are long periodlong period

earthquakes

earthquakes which are produced " the in*ection which are produced " the in*ection of magmaof magma

into surrounding roc%. These earth?ua%es are a result of

pressure changes during the unstead transport of the magma.

8hen magma in*ection is

8hen magma in*ection is sustained a lot of sustained a lot of earth?ua%es arearth?ua%es aree

produced. This tpe of activit indicates that

produced. This tpe of activit indicates that a volcano is a"outa volcano is a"out

to erupt. cientists use

to erupt. cientists use seismographs to record the signal fromseismographs to record the signal from

these earth?ua%es. This signal is %nown as

(23)

5

5 earth?ua%es

earth?ua%es

The second ca

The second categor of volcantegor of volcanicic

earth?ua%es are

earth?ua%es are long periodlong period

earthquakes

earthquakes which are which are

produced " the in*ection of

magma into surrounding roc%.

These earth?ua%es are a result

of pressure changes during

the unstead transport of the

magma. 8hen magma

in*ection is sustained a lot of

earth?ua%es are produced.

This tpe of activit indica

This tpe of activit indicatestes

that a volcano is a"out to

erupt. cientists use

seismographs to record the

signal from these

earth?ua%es. This signal is

%nown as

(24)

- ?uic% pic

(25)

- ?uic% pic

(26)

#i"liograph

• • httpFDDen.wi%ipedia.orgDwi%iDPlateGtectonics

httpFDDen.wi%ipedia.orgDwi%iDPlateGtectonics

• • httpFDDgeograph.a"out.comDodDphsicalgeog

httpFDDgeograph.a"out.comDodDphsicalgeog

raphDaDPlate5Tectonics.htm

• • httpFDDscience.nationalgeographic.co.inDscien

httpFDDscience.nationalgeographic.co.inDscien

ceDearthDthe5dnamic5earthDplate5tectonics5

articleD

• • httpFDDwww.enchantedlearning.comDsu"*ectsD

httpFDDwww.enchantedlearning.comDsu"*ectsD

volcanoD

• • httpFDDwww.platetectonics.comD"oo%DpageG;.

httpFDDwww.platetectonics.comD"oo%DpageG;.

asp