Origins of Plate Tectonic TheORY

7/25/2019 Origins of Plate Tectonic TheORY

1/10

Origins of Plate Tectonic TheoryBY ANNE E. EGGER, PH.D.

Reading

Quiz

Resources

10!"

Table of contents

Terms you should know Boo#$ar#

Glossary Ter$s

The Hi$alayas are often referre% to as the &roof of the 'orl%& (eca)se they

host the highest *ea#s on Earth, $ost fa$o)sly +t. Eerest at -,-- $eters

a(oe sea leel. B)t the roc# that ca*s +t. Eerest isli$estone, a ty*e of

roc# that for$s at the (otto$ of 'ar$, shallo' seas an% is co$*ose%

*ri$arily of fossili/e% $arine creat)res, eerything fro$ *lan#ton to cla$s

an% sh. or years, geologists str)ggle% to e2*lain ho' the re$ains of tiny

sea organis$sco)l% e2ist at the to* of a $o)ntain range.

3nto the 1400s, $any scientists (eliee% that as Earth coole% after its

for$ation, the *lanet5s s)rfacecontracte% an% 'rin#le% li#e the s#in of an

a**le, s)(6ecte% to the s)n an% %rying o)t oer ti$e. The contraction theory,

in%e*en%ently *ro*ose% (y t'o *ro$inent scientists in the late 1-00s an%

early 1400s, i$*lie% that $o)ntain ranges li#e the Hi$alayas 'ere force% )*

(y the 'rin#ling *rocess. This theory ass)$e% that all of the feat)res on

Earth ha% for$e% %)ring one cooling eent an% that the *lanet 'as relatiely

static, changing little as the cooling 7an% 'rin#ling8 slo'e% to a halt oer$illions of years.

Wegener proposes "continental drift"
http://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65/readinghttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65/quizhttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65/resourceshttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65http://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65http://www.visionlearning.com/en/user/signinhttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65http://www.visionlearning.com/en/glossary/view/limestone/pophttp://www.visionlearning.com/en/glossary/view/organism/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/process/pophttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65/quizhttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65/resourceshttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65http://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65http://www.visionlearning.com/en/user/signinhttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65http://www.visionlearning.com/en/glossary/view/limestone/pophttp://www.visionlearning.com/en/glossary/view/organism/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/process/pophttp://www.visionlearning.com/en/library/Earth-Science/6/Origins-of-Plate-Tectonic-Theory/65/reading


2/10

Alfre% 9egener, a Ger$an geo*hysicist an% $eteorologist, 'as not satise%

(y this e2*lanation. His i%eas %re' on the 'i%ely recogni/e% fact that Africa

an% :o)th A$erica a**eare% to t together li#e 6igsa' *)//le *ieces. He

collecte% *aleocli$ate %ata, or infor$ation a(o)t 'hat the cli$ate'as li#e

in the geologic *ast as recor%e% in roc#s, fro$ the continents on (oth si%es

of the Atlantic 7ig)re 18. He recogni/e% that (elts of coal, 'hich for$s in

tro*ical regions, crosse% fro$ North A$erica in E)ro*e an% Asia, far north of

the $o%ern tro*ics. He also fo)n% ei%encethat an ice sheet ha% once

a%ance% fro$ so)thern Africa an% 3n%ia 7see ig)re 18, a *heno$enon that

'as i$*ossi(le to e2*lain in the $o%ern arrange$ent of the continents.

Fi

gure 1:9egener;s $a* of *aleocli$ate %ata fro$ his 141< *)(lication,sho'ing the continents 6oine% together an% the (an%s of si$ilar roc# ty*esthat crosse% the oceans 79egener, 14"8.

To e2*lain these %ata, 9egener *ro*ose% the theoryof continental %riftin his

(oo# The Origins of the =ontinents an% the Oceans, *)(lishe% in Ger$an in

141< an% in English in 14" 79egener, 14"8. His theory state% that all of

the continents ha% originally (een 6oine% together %)ring the ti$e *erio%

calle% the =ar(onifero)s 7no' #no'n to (e a(o)t !00>!?0 $illion years ago8

in a s)*ercontinent calle% Pangaea7see ig)re " for his %e*iction8. By the

Eocene 7a(o)t


3/10

ha% (ro#en a*art an% 'ere far eno)gh a*art that s*ecies co)l% not easily

$igrate fro$ one to the other 7see ig)re ! for his %e*iction8.

Fi

gure :9egener;s %e*iction of Pangaea 79egener, 14"8. The %otte% areas'o)l% hae (een 'ar$, shallo' seas. 9egener *roi%e% the *resent>%ayo)tlines an% the riers for the *)r*ose of i%entication only.


4/10

Fi

gure !:A%%itional i$ages fro$ 9egener;s *)(lication, sho'ing ho' thecontinents @%rifte% thro)gh ti$e 79egener, 14"8.

ri#ing the drift

9hen 9egener5s (oo# 'as translate% into English, rench, :*anish, an%

R)ssian in 14", he 'as 'i%ely ri%ic)le% for his s)ggestion that the

continents ha% $oe%. One of the $ain *ro(le$s 'ith histheory'as that he

%i% not *ro*ose a %riing $echanis$ for the $otion of the continents. 9hat

'as the forcethat $oe% the continents 9here %i% it co$e fro$ Ho'

$)ch force 'as nee%e% to $oe a continent

The %riing $echanis$, an i$*ortant #ey to the continental %rifttheory, lay

o)t of reach )ntil the 14?0s. 9egener ha% $a%e his clai$s (ase%
http://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/force/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/force/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/theory/pop


5/10

on %atafro$ the continents, ()t the oceans coer C0 *ercent of

Earth5s s)rface a ast area hi%%en fro$ his ie' )n%er #ilo$eters of 'ater.

B)t the rst an% secon% 9orl% 9ars (ro)ght $a6or technical an% scientic

%eelo*$ents that allo'e% scientists to 718 $a* the ocean oor an% 7"8

$eas)re the $agnetis$of seaoorroc#s in %etail. These t'o sets of %ata

*roi%e% geologists 'ith a%%itional ei%encefor the *rocessof continental

%rift.

Comprehension Checkpoint

Why wasn$t Wegener$s theory of continental drift widely accepted at

%rst&

9egener %i% not *ro*ose a %riing force (ehin% continental %rift.

The continents of the 'orl% %i% not loo# as if they co)l% hae ttogether.

'apping the ocean (oor

Before the 14"0s, the cr)st(elo' the seas 'as tho)ght to (e at an%

feat)reless. D)ring 9orl% 9ar 3, ho'eer, shi*s eF)i**e% 'ith sonar (egan

to *ro%)ce %ataa(o)t the to*ogra*hy of the seaoor. These sonar $a*s

sho'e% the seaoor to (e anything ()t feat)reless instea%, the ocean oor

hoste% alleys %ee*er than the Gran% =anyon, $o)ntain chains rialing the

An%es (oth in length an% height, as 'ell as ast, at *lains.

+ost s)r*rising to scientists, a long ri%ge 'as fo)n% to r)n %o'n the $i%%le

of the Atlantic Ocean, rising 1 to " #$ a(oe the s)rro)n%ing ocean oor an%

*aralleling the continental coasts on (oth si%es. :i$ilar feat)res, calle%

@$i%>ocean ri%ges (y their %iscoerers, 'ere $a**e% in the eastern Pacic

Ocean an% the 'estern 3n%ian Ocean. Base% on the fact that they 'ere

*arallel to the e%ges of the continents, the ri%ges ha% so$ething to %o

'ith continental %rift, ()t 'hat

3n a 14?" *a*er entitle% &History of Ocean Basins,& Harry Hess, a geologist atPrinceton niersity, *ro*ose% that the $i%>ocean ri%ges$ar#e% regions

'here hot $ag$arose close to the s)rface7Hess, 14?"8. )rther, he

s)ggeste% that the e2tr)sionof $ag$a at the ri%ges *)she% the ocean oor

a'ay fro$ the ri%ges li#e a coneyor (elt. 3n %ee* trenches li#e those fo)n%

o the coast of :o)th A$erica an% Ia*an, the s*rea%ing ocean oor 'as
http://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/process/pophttp://www.visionlearning.com/en/glossary/view/crust/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/Hess%2C+Harry/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/extrusion/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/process/pophttp://www.visionlearning.com/en/glossary/view/crust/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/Hess%2C+Harry/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/extrusion/pop


6/10

force% %o'n (elo' the thic# continents in regions he

calle% s)(%)ction/ones. Hess5s theoryof &seaoor s*rea%ing& oere% a

co$*elling %riing $echanis$ for 9egener5s continental %rift, ()t it nee%e%

$ore *roof.


)cean (oors around the world

are $ostly at 'ith so$e ran%o$ ri%ges an% alleys.

hae %ee* alleys an% ri%ges that *arallel continental coasts.

*ea(oor magnetism

The sa$e year that Hess *ro*ose% his theory, the : Nay *)(lishe% a

re*ort that s)$$ari/e% its n%ings concerning seaoor$agnetis$. D)ring9orl% 9ar 33, shi*s %ragge% $agneto$eters, 'hich are %eices to $eas)re

$agnetis$, in or%er to locate s)($arines. The $agneto$eters 'ere on an%

$eas)ring at all ti$es 'hile the shi*s traele% (ac# an% forth across the

Atlantic an% Pacic, an% they fo)n% a lot $ore than s)($arines. 9hen Nay

scientists e2a$ine% the %ata, they fo)n% (an%s of alternating strong an%

'ea# $agnetis$ in the roc#s of the seaoor 7see ig)re 8.

Figure +:An e2a$*le of$agnetic %ata collecte% (y shi* across the I)an %e )ca ri%ge o the coast of9ashington state. Ga$$as are a )nit of $agnetic force.

The $agnetis$'as ca)se% (y the *resence of $agnetic $ineralsin the

roc#s, *ri$arily one calle% $agnetite, 'hich is co$$on in the (asaltthat

$a#es )* the roc#s of the ocean oor. 9hen $ag$acools an% crystalli/es,

the $agnetite crystalsare loc#e% into align$ent 'ith Earth5s $agnetic el%

li#e the nee%le of a co$*ass 7see o)r Earth :tr)ct)re$o%)le8.

The e2istence of Earth5s $agnetic el% ha% (een #no'n since ancient ti$es,

()t only after 9orl% 9ar 33 %i% scientists reali/e that the $agnetic el% is

not constant> it )ct)ates in intensity an% freF)ently reerses itself. To%ay

'e consi%er the el% to hae &nor$al& *olarity, an% o)r co$*ass nee%les

*oint to the north. B)t at ario)s ti$es in the *ast, the *olarity has (een

reerse% > any co$*ass nee%les 'o)l% hae instea% *ointe% to the :o)th
http://www.visionlearning.com/en/glossary/view/subduction/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/mineral/pophttp://www.visionlearning.com/en/glossary/view/basalt/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/crystal/pophttp://www.visionlearning.com/library/module_viewer.php?mid=69http://www.visionlearning.com/en/glossary/view/constant/pophttp://www.visionlearning.com/en/glossary/view/polarity/pophttp://www.visionlearning.com/en/glossary/view/subduction/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/mineral/pophttp://www.visionlearning.com/en/glossary/view/basalt/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/crystal/pophttp://www.visionlearning.com/library/module_viewer.php?mid=69http://www.visionlearning.com/en/glossary/view/constant/pophttp://www.visionlearning.com/en/glossary/view/polarity/pop


7/10

Pole. This *heno$enon of $agnetic reersals ha% *reio)sly (een o(sere%

in continental roc#s, an% 'as clearly the case for oceanic roc#s as 'ell.

The (asalton the ocean oor *resere% *aleo$agnetic

reersals ei%encethat Earth;s $agnetic el% ha% i**e% fro$ nor$al to

reerse% $any ti$es thro)gho)t geologic history.

,roof of sea(oor spreading

3n 14?!, re% Jine an% Dr)$$on% +atthe's, t'o British geologists, 6oine%

the to*ogra*hic $a* of the +i%>Atlantic Ri%ge 'ith the sy$$etric (an%s

of $agnetis$on the seaoor7Jine an% +atthe's, 14?!8. 9here the nay

shi*s $a**e% strong $agnetis$, roc#s sho'e% nor$al *olarityK 'here they

$a**e% (an%s of 'ea# $agnetis$, the roc#s sho'e% reerse% *olarity. The

(an%s not only *arallele% the $i%>ocean ri%ges, ()t 'ere *atterne%

sy$$etrically a(o)t the crest of those ri%ges 7see ig)re < for an e2a$*le8.
http://www.visionlearning.com/en/glossary/view/basalt/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/Matthews%2C+Drummond/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/polarity/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pophttp://www.visionlearning.com/en/glossary/view/basalt/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/Matthews%2C+Drummond/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/polarity/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pop


8/10

Figur

e -:The $agnetic *role sho'n in ig)re co$(ine% 'ith to*ogra*hy an%the location of the s*rea%ing ri%ge.

At the crests, the $agnetis$'as strongK therefore, the *olarity'as nor$al.

B)t $oing in either %irection a'ay fro$ the ri%ge, the $agnetis$ 'o)l%

%ro* s)%%enly at a(o)t the sa$e %istance fro$ the crest the *olarity 'as

reerse%. =ontin)e a'ay fro$ the ri%ge in (oth %irections, an% $agnetis$

'o)l% s)%%enly (e strong again (ac# into roc#s 'ith nor$al *olarity. The

sy$$etry s)ggeste% that$ag$a'as rising at the ri%ges an% cooling to loc#

in the $agnetic el% at the ti$e, then (eing *)she% a'ay fro$ the ri%ge in

(oth %irections, *resering a recor%of *aleo$agnetic reersalsan%

the generationof ne' cr)stoer ti$e 7see +i%>Ocean Ri%gesconce*t

si$)lation8.
http://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/polarity/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/record/pophttp://www.visionlearning.com/en/glossary/view/paleomagnetic+reversals/pophttp://www.visionlearning.com/en/glossary/view/generation/pophttp://www.visionlearning.com/en/glossary/view/crust/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pophttp://www.visionlearning.com/en/glossary/view/magnetism/pophttp://www.visionlearning.com/en/glossary/view/polarity/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/record/pophttp://www.visionlearning.com/en/glossary/view/paleomagnetic+reversals/pophttp://www.visionlearning.com/en/glossary/view/generation/pophttp://www.visionlearning.com/en/glossary/view/crust/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pop


9/10

Interactive Animation:'id.ocean ridges

These strongly *atterne% *aleo$agnetic reersalsrecor%e% on

the seaoor*roi%e% the necessary *roof of Hess5s seaoor s*rea%ing.

:*ecically, they *roe% that ne' cr)st'as contin)o)sly (eing generate% at

the $i%>ocean ri%ges, 'here $ag$acoole% an% $agnetite crystals&loc#e%

in& accor%ing to the orientation of Earth5s $agnetic el% at that ti$e. The

continents no longer ha% to &%rift& to their *resent locations they co)l% (e

%rien (y slo' an% stea%y $ag$a &coneyor (elts& that originate% at the

$i%>ocean ri%ges.

The 'or# of Hess, Jine, an% +atthe's res)lte% in a ne' $a* of Earth thathighlighte% the feat)res of the ocean oor, one that incl)%e% *late

(o)n%aries in a%%ition to coastlines. Plate (o)n%aries co)l% (e %ra'n at $i%>

oceanic ri%ges an% s)(%)ction/ones 7see ig)re ?8.

Fi

gure /:Re% lines in%icate s*rea%ing ri%gesK yello' lines in%icate s)(%)ction/ones. Light (l)e lines %on;t t either category.


'agnetic stripes on the sea(oor are e#idence for

constant a%%ition of $ag$a to the cr)st at $i%>ocean ri%ges.
http://www.visionlearning.com/library/animations/Mid_Ocean_Ridge/MOR_Interactive.htmlhttp://www.visionlearning.com/library/animations/Mid_Ocean_Ridge/MOR_Interactive.htmlhttp://www.visionlearning.com/en/glossary/view/paleomagnetic+reversals/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/seafloor+spreading/pophttp://www.visionlearning.com/en/glossary/view/crust/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/crystal/pophttp://www.visionlearning.com/en/glossary/view/subduction/pophttp://www.visionlearning.com/library/animations/Mid_Ocean_Ridge/MOR_Interactive.htmlhttp://www.visionlearning.com/en/glossary/view/paleomagnetic+reversals/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/seafloor+spreading/pophttp://www.visionlearning.com/en/glossary/view/crust/pophttp://www.visionlearning.com/en/glossary/view/mid~ocean+ridge/pophttp://www.visionlearning.com/en/glossary/view/magma/pophttp://www.visionlearning.com/en/glossary/view/crystal/pophttp://www.visionlearning.com/en/glossary/view/subduction/pop


10/10

%rifting of continents thro)gh the cr)st.

)ngoing 0#idencefor ,late TectonicsTo%ay, $)ch of the ei%enceconcerning *late tectonics is acF)ire% 'ith

satellite technology. Thro)gh )se of the glo(al *ositioning syste$7GP:8 an%

other satellite>(ase% %atacollection techniF)es, scientists can %irectly

$eas)re the elocity7or s*ee% an% %irection of $oe$ent8 of *lates on

Earth;ss)rface. :*ee%s range fro$ 10 to 100 $$ *er year, conr$ing the

long>hel% (elief that *lates $oe at a slo' ()t constantrate 7see o)r $o%)le

on Linear EF)ationsfor $ore %etail on ho' to calc)late rates of *late

$oe$ent8.

The Hi$alayas, as it t)rns o)t, starte% for$ing a(o)t 0 $illion years ago

'hen the 3n%ian Plate colli%e% hea%>on 'ith the E)rasian Plate, shoing an%

fol%ing roc#s that ha% for$e% (elo' sea leel into lofty *ea#s. Beca)se the3n%ian Plate is still $oing north'ar%, the Hi$alayas are still rising at a rate

of a(o)t 1 c$ *er year. 9e no longer nee% to ino#e a shrin#ing, 'rin#le%

Earth to e2*lain the $arine fossilsat the to* of these tall $o)ntainsK it is

the *rocessof *late tectonics that contin)es to lift seaoorroc#s to the s#y.

Earth is incre%i(ly %yna$ic $o)ntain chains ()il% an% ero%e a'ay,

olcanoes er)*t an% go e2tinct, seas a%ance an% rece%e an% these

changes are all a res)lt of the *rocesses of *late tectonics. Before 9egener,

fe' ha% conceie% of s)ch a 'orl%. His continental %rifttheory'as the rst

ste* in the %eelo*$ent of *late tectonic theory, the fo)n%ation )*on 'hich

$o%ern geology is ()ilt.

*ummary
http://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/Global+Positioning+System/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/velocity/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/constant/pophttp://www.visionlearning.com/en/library/Math-in-Science/62/Linear-Equations-in-Science/194http://www.visionlearning.com/en/glossary/view/fossil/pophttp://www.visionlearning.com/en/glossary/view/process/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/extinction/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/theory/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/evidence/pophttp://www.visionlearning.com/en/glossary/view/Global+Positioning+System/pophttp://www.visionlearning.com/en/glossary/view/data/pophttp://www.visionlearning.com/en/glossary/view/velocity/pophttp://www.visionlearning.com/en/glossary/view/surface/pophttp://www.visionlearning.com/en/glossary/view/constant/pophttp://www.visionlearning.com/en/library/Math-in-Science/62/Linear-Equations-in-Science/194http://www.visionlearning.com/en/glossary/view/fossil/pophttp://www.visionlearning.com/en/glossary/view/process/pophttp://www.visionlearning.com/en/glossary/view/seafloor/pophttp://www.visionlearning.com/en/glossary/view/extinction/pophttp://www.visionlearning.com/en/glossary/view/continental+drift/pophttp://www.visionlearning.com/en/glossary/view/theory/pop

Documents

Origins of Plate Tectonic TheORY