VL Geodynamik & Tektonik, WS 080921.01.2009 Plattentektonik Institut für Geowissenschaften...

VL Geodynamik & Tektonik, WS 080921.01.2009

PlattentektonikPlattentektonik

Institut für Geowissenschaften Universität Potsdam

VL Geodynamik & Tektonik, WS 0809

Übersicht zur Vorlesung


Plattentektonik

3 Typen von Plattengrenzen

Ozeane Kontinente


VL Geodynamik & Tektonik, WS 0809Earth’s PlatesEarth’s Plates


Divergent boundaries are located Divergent boundaries are located mainly along oceanic ridgesmainly along oceanic ridges


Divergent plate boundariesDivergent plate boundaries

Oceanic ridges and seafloor spreading Seafloor spreading occurs along the oceanic

ridge system

Spreading rates and ridge topography Ridge systems exhibit topographic differences Topographic differences are controlled by

spreading rates


Ridge morphologyRidge morphology

Faster spreading ridges are characterized by more volcanism smoother topography - less faulting fewer moderate earthquakes

Slower spreading ridges are characterized by less volcanism rough topography - more extension by faulting more moderate sized earthquakes

The differences are related to temperature.



Spreading rates and ridge topography Topographic differences are controlled by

spreading rates– At slow spreading rates (1-5 centimeters per year), a

prominent rift valley develops along the ridge crest that is wide (30 to 50 km) and deep (1500-3000 meters)

– At intermediate spreading rates (5-9 cm per year), rift valleys that develop are shallow with subdued topography



Spreading rates and ridge topography Topographic differences are controlled by

spreading rates– At spreading rates greater than 9 centimeters per

year no median rift valley develops and these areas are usually narrow and extensively faulted

Continental rifts Splits landmasses into two or more smaller

segments



Continental rifts Examples include the East African rifts valleys

and the Rhine Valley in northern Europe Produced by extensional forces acting on the

lithospheric plates Not all rift valleys develop into full-fledged

spreading centers


The East African rift – The East African rift – a divergent boundary on landa divergent boundary on land


Convergent plate boundariesConvergent plate boundaries

Older portions of oceanic plates are returned to the mantle in these destructive plate margins

Surface expression of the descending plate is an ocean trench

Called subduction zones Average angle at which oceanic lithosphere

descends into the mantle is about 45



Although all have the same basic charac-teristics, they are highly variable features

Types of convergent boundaries Oceanic-continental convergence

– Denser oceanic slab sinks into the asthenosphere



Types of convergent boundaries Oceanic-continental convergence

– As the plate descends, partial melting of mantle rock generates magmas having a basaltic or, occasionally andesitic composition

– Mountains produced in part by volcanic activity associated with subduction of oceanic lithosphere are called continental volcanic arcs (Andes and Cascades)


An oceanic-continental convergent An oceanic-continental convergent plate boundaryplate boundary



Types of convergent boundaries Oceanic-oceanic convergence

– When two oceanic slabs converge, one descends beneath the other

– Often forms volcanoes on the ocean floor– If the volcanoes emerge as islands, a volcanic island

arc is formed (Japan, Aleutian islands, Tonga islands)


An oceanic-oceanic convergent An oceanic-oceanic convergent plate boundaryplate boundary



Types of convergent boundaries Continental-continental convergence

– Continued subduction can bring two continents together

– Less dense, buoyant continental lithosphere does not subduct

– Result is a collision between two continental blocks – Process produces mountains (Himalayas, Alps,

Appalachians)


A continental-continental convergent A continental-continental convergent plate boundaryplate boundary


The collision of India and Asia The collision of India and Asia produced the Himalayasproduced the Himalayas


Transform fault boundariesTransform fault boundaries

The third type of plate boundary Plates slide past one another and no new

lithosphere is created or destroyed Transform faults

Most join two segments of a mid-ocean ridge as parts of prominent linear breaks in the oceanic crust known as fracture zones



VL Geodynamik & Tektonik, WS 0809East Pacific Rise west of Costa Rica



Transform faultsA few (the San Andreas fault and the

Alpine fault of New Zealand) cut through continental crust


Transform Margin


Testing the plate tectonics modelTesting the plate tectonics model

Paleomagnetism Ancient magnetism preserved in rocks at the

time of their formation Magnetized minerals in rocks

– Show the direction to Earth’s magnetic poles – Provide a means of determining their latitude of

origin


•Dip of needle = inclination

•When a rock cools below the Curie point, the magnetization direction is locked in

•We can determine the “paleolatitude”

•Also used in archeology



PaleomagnetismPaleomagnetismThe measurement of remnant magnetism can provide information important information about where a rock may have come from.

Measuring a paleomagnetic direction:

•An individual lava flow may not record an “average” pole (secular variation), so samples from a series of flows may be taken

•Oriented (azimuth and dip) rock cores separated by up to a few meters are drilled (using non-magnetic equipment).

•If the rock has been tilted since its formation, this has to be measured.

•The magnetization direction is measured (by measuring all three axis of the core) using a very sensitive magnetometer.

•The direction, which is relative to the cylinder is calculated with respect to north and the vertical.

•The magnetization direction is plotted on a stereonet.


PaleomagnetismPaleomagnetism• Magnetic inclination varies from

vertical in the center to horizontal at the circumference.

• Declination is the angle around the circle clockwise from north.

• Downward magnetizations (positive inclination) are plotted as open circle. Negative magnetizations are plotted as solid circles.

• Plot mean direction and 95% confidence interval (95% probability of containing the true direction).

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MagnetostratigraphyMagnetostratigraphy•By measuring the polarity of magnetization of a rock of know age (radiometric data, sediment on ocean floor above basement) we can build up a magnetic polarity timescale.

•At even smaller scales we can examine secular variation within a series of lava flow (assuming a high resolution series of flows).

•If these flows are historic, we could probably date them.

•If they are very old, we could use the pattern of secular variation to correlate between outcrops.

•Archeological applications – dating ancient fireplaces.

•The resultant magnetic timescale can be used to date sediments and the seafloor by the recognition of distinctive reversal patterns.

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Geomagnetic ReversalsGeomagnetic Reversals

The first comprehensive magnetic study was carried out off the Pacific coast of North America.

Researchers discovered alternating strips of high- and low- intensity magnetism.

In 1963 Vine and Matthews demonstrated that stripes of high intensity magnetism formed when the Earth’s magnetic field was in the present direction, and stripes of low intensity magnetism formed when the Earth’s magnetic field was in the reversed direction.


A scientific revolution beginsA scientific revolution begins

During the 1950s and 1960s technological strides permitted extensive mapping of the ocean floor

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An Extensive oceanic ridge system was discovered.

Part of this system is the Mid-Atlantic Ridge.

A central valley shows us that tensional forces are pulling the ocean crust apart at the ridge crest.

High heat flow. Volcanism.



Deep earthquakes showed that tectonic activity was taking place beneath the deep trenches.

Flat topped seamounts were discovered hundreds of meters below sea level.

Dredges of rocks from the seafloor did not recover any rocks older than 180 million years old.

Sediment thickness on the seafloor was much less than expected (the seafloor being younger than expected).



Paleomagnetism Polar wandering

– The apparent movement of the magnetic poles illustrated in magnetized rocks indicates that the continents have moved

– Polar wandering curves for North America and Europe have similar paths but are separated by about 24 of longitude

– Different paths can be reconciled if the continents are place next to one another


Apparent polar-wandering paths for Apparent polar-wandering paths for Eurasia and North AmericaEurasia and North America



Magnetic reversals and seafloor spreading Earth's magnetic field periodically reverses

polarity – the north magnetic pole becomes the south magnetic pole, and vice versa

Dates when the polarity of Earth’s magnetism changed were determined from lava flows



Magnetic reversals and seafloor spreading Geomagnetic reversals are recorded in the

ocean crust In 1963 the discovery of magnetic stripes in the

ocean crust near ridge crests was tied to the concept of seafloor spreading


Paleomagnetic reversals recorded by Paleomagnetic reversals recorded by basalt at mid-ocean ridgesbasalt at mid-ocean ridges


Inpretation of magnetic anomalies from ship-track wiggles, (Barckhausen et al. 2001).



Magnetic reversals and seafloor spreading Paleomagnetism (evidence of past magnetism

recorded in the rocks) was the most convincing evidence set forth to support the concept of seafloor spreading

The Pacific has a faster spreading rate than the Atlantic



Plate tectonics and earthquakes Plate tectonics model accounts for the global

distribution of earthquakes – Absence of deep-focus earthquakes along the

oceanic ridge is consistent with plate tectonics theory – Deep-focus earthquakes are closely associated with

subduction zones – The pattern of earthquakes along a trench provides a

method for tracking the plate's descent


Deep-focus earthquakes occur along Deep-focus earthquakes occur along convergent boundariesconvergent boundaries


Earthquake foci in the vicinity Earthquake foci in the vicinity of the Japan trenchof the Japan trench



Evidence from ocean drillingSome of the most convincing evidence

confirming seafloor spreading has come from drilling directly into ocean-floor sediment

– Age of deepest sediments – Thickness of ocean-floor sediments verifies

seafloor spreading



Hot spots Caused by rising plumes of mantle

material Volcanoes can form over them

(Hawaiian Island chain)Most mantle plumes are long-lived

structures and at least some originate at great depth, perhaps at the mantle-core boundary


The Hawaiian Islands have formed The Hawaiian Islands have formed over a stationary hot spotover a stationary hot spot


Measuring plate motionsMeasuring plate motions

A number of methods have been em-ployed to establish the direction and rate of plate motion

Volcanic chains Paleomagnetism Very Long Baseline Interferometry (VLBI) Global Positioning System (GPS)


Measuring plate motionsMeasuring plate motions

Calculations show that Hawaii is moving in a northwesterly

direction and approaching Japan at 8.3 centimeters per year

A site located in Maryland is retreating from one in England at a rate of about 1.7 centimeters per year


The driving mechanismThe driving mechanism

No one driving mechanism accounts for all major facets of plate tectonics

Several mechanisms generate forces that contribute to plate motion

Ridge push Slab pull

Models– Layering at 660 kilometers – Whole-mantle convection – Deep-layer model


DeformationDeformation

Deformation is a general term that refers to all changes in the original form and/or size of a rock body

Most crustal deformation occurs along plate margins

How rocks deformRocks subjected to stresses greater

than their own strength begin to deform usually by folding, flowing, or fracturing


FaultsFaults

Faults are fractures in rocks along which appreciable displacement has taken place

Sudden movements along faults are the cause of most earthquakes

Classified by their relative movement which can be

Horizontal, vertical, or oblique


FaultsFaults

Types of faultsDip-slip faults

– Movement is mainly parallel to the dip of the fault surface

– May produce long, low cliffs called fault scarps

– Parts of a dip-slip fault include the hanging wall (rock surface above the fault) and the footwall (rock surface below the fault)


Concept of hanging wall and footwall Concept of hanging wall and footwall along a faultalong a fault


FaultsFaults

Types of dip-slip faults– Normal fault

• Hanging wall block moves down relative to the footwall block

• Accommodate lengthening or extension of the crust

• Most are small with displacements of a meter or so

• Larger scale normal faults are associated with structures called fault-block mountains


A normal fault A normal fault


FaultsFaults

Types of dip-slip faults– Reverse and thrust faults

• Hanging wall block moves up relative to the footwall block

• Reverse faults have dips greater than 45o and thrust faults have dips less then 45o

• Accommodate shortening of the crust• Strong compressional forces


A reverse faultA reverse fault


A thrust fault A thrust fault


FaultsFaults

Strike-slip fault Dominant displacement is horizontal and

parallel to the strike of the fault Types of strike-slip faults

– Right-lateral – as you face the fault, the block on the opposite side of the fault moves to the right

– Left-lateral – as you face the fault, the block on the opposite side of the fault moves to the left


A strike-slip faultA strike-slip fault


FaultFault

Strike-slip faultTransform fault

– Large strike-slip fault that cuts through the lithosphere

– Accommodates motion between two large crustal plates


The San Andreas fault system The San Andreas fault system is a major transform faultis a major transform fault


Mountain beltsMountain belts

Orogenesis – the processes that col-lectively produce a mountain belt

Includes folding, thrust faulting, meta-morphism, and igneous activity

Mountain building has occurred during the recent geologic past

Alpine-Himalayan chain American Cordillera Mountainous terrains of the western

Pacific


Earth’s major mountain beltsEarth’s major mountain belts


Mountain beltsMountain belts

Older Paleozoic- and Precambrian-age mountains

Appalachians Urals in Russia

Several hypotheses have been proposed for the formations of Earth’s mountain belts


Mountain building at Mountain building at convergent boundariesconvergent boundaries

Plate tectonics provides a model for orogenesis Mountain building occurs at convergent plate boundaries Of particular interest are active subduction zones

– Volcanic arcs are typified by the Aleutian Islands and the Andean arc of western South America



Aleutian-type mountain building Where two ocean plates converge and one is subducted

beneath the other Volcanic island arcs result from the steady subduction of

oceanic lithosphere – Most are found in the Pacific – Active island arcs include the Mariana, New Hebrides,

Tonga, and Aleutian arcs



Aleutian-type mountain building Volcanic island arcs

– Continued development can result in the formation of mountainous topography consisting of igneous and metamorphic rocks


Formation of a volcanic island arcFormation of a volcanic island arc



Andean-type mountain building Mountain building along continental margins

– Involves the convergence of an oceanic plate and a plate whose leading edge contains continental crust

– Exemplified by the Andes Mountains



Andean-type mountain building Stages of development - passive margin

– First stage– Continental margin is part of the same plate as the

adjoining oceanic crust – Deposition of sediment on the continental shelf is

producing a thick wedge of shallow-water sediments– Turbidity currents are depositing sediment on the

continental rise and slope



Andean-type mountain building Stages of development – active continental margins

– Subduction zone forms – Deformation process begins – Convergence of the continental block and the subducting

oceanic plate leads to deformation and metamorphism of the continental margin

– Continental volcanic arc develops



Andean-type mountain building Composed of roughly two parallel zones

– Accretionary wedge

• Seaward segment

• Consists of folded, faulted, and meta-morphosed sediments and volcanic debris


Orogenesis along an Andean-type Orogenesis along an Andean-type subduction zonesubduction zone







Continental collisions Two lithospheric plates, both carrying continental crust The Himalayan Mountains are a youthful mountain range

formed from the collision of India with the Eurasian plate about 45 million years ago



Continental collisions The Himalayan Mountains

– Spreading center that propelled India northward is still active

– Similar but older collision occurred when the European continent collided with the Asian continent to produce the Ural mountains


Plate relationships prior to the Plate relationships prior to the collision of India with Eurasiacollision of India with Eurasia


Position of India in relation to Eurasia Position of India in relation to Eurasia at various timesat various times


Formation of the HimalayasFormation of the Himalayas



Continental accretion and mountain building A third mechanism of orogenesis Small crustal fragments collide and merge with

continental margins Responsible for many of the mountainous regions

rimming the Pacific Accreted crustal blocks are called terranes



Continental accretion and mountain building Terranes consist of any crustal fragments whose

geologic history is distinct from that of the adjoining terranes

As oceanic plates move, they carry embedded oceanic plateaus, volcanic island arcs and microcontinents to an Andean-type subduction zone


Vertical movements of the crustVertical movements of the crust

In addition to the horizontal movements of lithospheric plates, vertical movement also occurs along plate margins as well as the interiors of continents far from plate boundaries


Vertical movements of the crustVertical movements of the crust

Isostatic adjustment Less dense crust floats on top of the denser

and deformable rocks of the mantle Concept of floating crust in gravitational

balance is called isostasy If weight is added or removed from the crust,

isostatic adjustment will take place as the crust subsides or rebounds


Der Wilson-ZyklusDer Wilson-Zyklus

Ein Wilson-Zyklus beschreibt die Entstehung, die Entwicklung und das Verschwinden eines Ozeans.

Ein Wilson-Zyklus beschreibt die Entstehung, die Entwicklung und das Verschwinden eines Ozeans.

Die einzelnen Stadien sind: Zerbrechen kontinentaler Kruste, Entstehung einer ozeanischen Spreizungszone, maximale Ausdehnung der Ozeanischen Kruste, Subduktion, Verschwinden der ozeanischenKruste, Kontinent – Kontinent - Kollision

Die einzelnen Stadien sind: Zerbrechen kontinentaler Kruste, Entstehung einer ozeanischen Spreizungszone, maximale Ausdehnung der Ozeanischen Kruste, Subduktion, Verschwinden der ozeanischenKruste, Kontinent – Kontinent - Kollision


Die Stadien eines Wilson-ZyklusDie Stadien eines Wilson-ZyklusAn verschieden weit entwickelter ozeanischer Kruste kann man

einzelne Stadien eines Wilson-Zyklus beobachten:

Bildung eines kontinentalen Grabens (Ostafrikanischer Graben)Bildung eines kontinentalen Grabens (Ostafrikanischer Graben)

Beginnende Ozeanisierung (Rotes Meer) Beginnende Ozeanisierung (Rotes Meer)

Maximale Ausdehnung der ozeanischen Kruste mit passiven Kontinentalrändern (Atlantik)

Maximale Ausdehnung der ozeanischen Kruste mit passiven Kontinentalrändern (Atlantik)

Subduktion der ozeanischen Kruste mit aktiven Kontinental- rändern (Pazifik)

Subduktion der ozeanischen Kruste mit aktiven Kontinental- rändern (Pazifik)

Restozean (Mittelmeer)Restozean (Mittelmeer)

Kontinent – Kontinent – Kollision (Himalaya)Kontinent – Kontinent – Kollision (Himalaya)


1.) Grabenbildung (Rifting)1.) Grabenbildung (Rifting) Beginnt mit einem Tripelpunkt auf kontinentaler Kruste

Süd-Amerika Afrika

Äquator

Kreide

Äquator

Rezent

Tripelpunkt

Benue-Trog(Aulakogen)

Rotes Meer

Afar-Senke

Golf von Aden


Entwicklung eines kontinentalen Entwicklung eines kontinentalen GrabensGrabens

aufdringendes basaltisches Magma

LavadeckenTuffe, vulkanischer Schutt

terrestrische Sedimente

Evaporite (Salze)


Der Rhein Rhône-GrabenDer Rhein Rhône-Graben

Tiefe der Kruste-Mantel-Grenze


Profil durch den RheingrabenProfil durch den Rheingraben

Asthenolith(Mantelkissen,Manteldiapir)

Oberer MantelKontinentaleKruste


Der Ostafrikanische GrabenDer Ostafrikanische Graben

Nairobi

WesternRift

GregoryRift

W E

Länge 4 000 kmBreite 30 – 70 kmVersatz > 6 000 m

Länge 4 000 kmBreite 30 – 70 kmVersatz > 6 000 m


Merkmale von kontinentalen GräbenMerkmale von kontinentalen Gräben

Hohe SeismizitätHohe Seismizität

Hoher Wärmefluß (> 2.0 HFU)Hoher Wärmefluß (> 2.0 HFU)

Alkaliner Magmatismus undVulkanismusAlkaliner Magmatismus undVulkanismus

Negative Schwere-Anomalie(Bouguer-Schwere)Negative Schwere-Anomalie(Bouguer-Schwere)


Schwere-AnomalieSchwere-Anomalie

Gemessen wird die Erdbeschleunigung in gal1 gal = 1 cm/sec2 = 1000 mgal.

normal: 980 gal

Gemessen wird die Erdbeschleunigung in gal1 gal = 1 cm/sec2 = 1000 mgal.

normal: 980 gal

~7.0>8.0 >8.0

+ +-Bouguer- Schwere

hochliegendeMoho

leichteSedimente


Bildung eines Bildung eines mittelozeanischenmittelozeanischen

RückensRückens

Bildung eines Bildung eines mittelozeanischenmittelozeanischen

RückensRückens

2.) Stadium2.) Stadium


Entstehung neuer ozeanischer KrusteEntstehung neuer ozeanischer Kruste

Beispiel: Rotes Meer, Golf von Aden,Afar- (Danakil-) Senke

Beispiel: Rotes Meer, Golf von Aden,Afar- (Danakil-) Senke

Rotes MeerRotes Meer

Golf von AdenGolf von Aden

Afar - DreieckAfar - Dreieck


Unterschiede zu GräbenUnterschiede zu Gräben

Entstehung ozeanischer KrusteEntstehung ozeanischer Kruste

Positive Bouguer-AnomaliePositive Bouguer-Anomalie


Ausbreitung ozeanischer Ausbreitung ozeanischer LithosphäreLithosphäre

Ausbreitung ozeanischer Ausbreitung ozeanischer LithosphäreLithosphäre

3. Stadium3. Stadium


Maximale Öffnung eines OzeansMaximale Öffnung eines Ozeans

nach Press & Siever (Spektrum Lehrbuch), 1995

Beispiel Atlantik

passiveKontinentalränder

Tiefseebecken


Profil durch den AtlantikProfil durch den Atlantik

Kontinental-rand

Kontinental-randTiefsee-

BeckenTiefsee-Becken

MittelozeanischerRücken

2000m4000m

Kontinental-rand

Kontinental-randTiefsee-

BeckenTiefsee-Becken

MittelozeanischerRücken

2000m4000m

Schematisches Profil durch den Nordatlantik


Stadium 4Stadium 4Subduktion ozeanischer Subduktion ozeanischer

KrusteKruste(rezentes Beispiel: Pazifik)(rezentes Beispiel: Pazifik)


SubduktionSubduktion3. Magmatischer Bogen

3. Magmatischer Bogen

4. Seismizität an der Wadati- Benioff-Zone

4. Seismizität an der Wadati- Benioff-Zone

Hochdruck-Niedrig-temperatur-Metam.

Hochdruck-Niedrig-temperatur-Metam.

Hochtemperatur-Niedrigdruck-Metam.

Hochtemperatur-Niedrigdruck-Metam.

5. paarige metamorphe Gürtel

5. paarige metamorphe Gürtel


paarige metamorphe Gürtel in Japanpaarige metamorphe Gürtel in Japan


Fossile Subduktionszonen:Fossile Subduktionszonen:

Eine ehemalige Subduktionszone erkennt man am Vorhandensein von:

Ophiolithen(Ophiolithische Sutur)

Ophiolithen(Ophiolithische Sutur)

magmatischen Gesteinenmagmatischen Gesteinen

Hochdruck-Gesteinen (Blauschiefer)Hochdruck-Gesteinen (Blauschiefer)


steilerEintauch-winkel

Bildung von RandbeckenBildung von Randbecken

Flacher EintauchwinkelHigh StressSubduktionHigh StressSubduktion

Low StressSubduktionLow StressSubduktion


Stadium 5Stadium 5RestmeerRestmeer

(Beispiel: Mittelmeer) (Beispiel: Mittelmeer)

Stadium 5Stadium 5RestmeerRestmeer

(Beispiel: Mittelmeer) (Beispiel: Mittelmeer)


Das Mittelmeer und Schwarze Meer Das Mittelmeer und Schwarze Meer als Restmeereals Restmeere

Aus Press & Siever, 1995 (Spektrum Lehrbücher)


Terrankarte des MittelmeersTerrankarte des Mittelmeers


Stadium 6Stadium 6Kontinent-Kontinent-KollisionKontinent-Kontinent-Kollision

Stadium 6Stadium 6Kontinent-Kontinent-KollisionKontinent-Kontinent-Kollision


Kontinent-Kontinent-KollisionKontinent-Kontinent-Kollision

Asthenosphäre

Litho-sphäre

Vorland-becken

Zentral-gürtel

Akkretions-keil

Geo

sutu

r

Hinterland

Regionale Metamorphoseund Anatexis Mantel-

delamination

Umgezeichnet nach Eisbacher, 1991


Kontinent-Kontinent-KollisionKontinent-Kontinent-Kollision

kontinentaleKruste

kontinentaleKruste

kontinentaleKruste

kontinentaleKruste

Slab-breakoff

Slab-breakoff

Über-schiebungen

Über-schiebungen

Sutur-zone

Sutur-zone

OphiolitheOphiolithe

MélangeMélange

Umgezeichnet nach Press & Siever, 1995 (Spektrum)

UnderplatingUnderplating


Kollision Indiens mit EurasienKollision Indiens mit Eurasien

Krustenver-kürzunginsgesamt2000 kmin 40 Ma

Krustenver-kürzunginsgesamt2000 kmin 40 Ma

Aus Press & Siever, 1995 (Spektrum Lehrbücher)


Entstehung des HimalayaEntstehung des Himalaya

University of Western Australia


Tektonik im Himalaya-HinterlandTektonik im Himalaya-Hinterland

Konvergenz

Dehnung

Escape-Tektonik

VL Geodynamik & Tektonik, WS 080921.01.2009

ZusammenfassungZusammenfassung

Die Plattentektonik ist der an der Erdoberfläche auftretende Ausdruck der Mantelkonvektion im Erdinneren. Sie

beschreibt die Bewegungen der Lithosphärenplatten und die daraus resultierenden geologischen Prozesse.

Zu diesen zählen u.a. die Entstehung von Faltengebirgen („Orogenese“), von mittelozeansichen Rücken und von

Transformstörungen.

Die großräumigen Deformationen der Lithosphäre sind wiederum die Ursache von zahlreichen geophysikalischen

Phänomenen, wie z.B. Vulkanismus oder Seismizität.

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