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Tettonica delle Placche qualche approccio alternativo soprattutto per i NON geologi Dipartimento di Scienze della Terra “A. Desio” – Via Mangiagalli, 34 - 20133 [email protected]

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Page 1: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

qualche approccio alternativo soprattutto per i NON geologi

Dipartimento di Scienze della Terra “A. Desio” – Via Mangiagalli, 34 - 20133

[email protected]

Page 2: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

da cosa partiamo?

Plate Tectonics

Page 3: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

da cosa partiamo?

Plate Tectonics

➡ da voi

GEO

BIO

NAT

Page 4: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

cosa sappiamo/sanno?

Plate Tectonics

minerali?

rocce?

vulcani?

evol

uzio

ne d

el te

rrito

rio?

Page 5: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

cosa non va?

Plate Tectonics

manca il contesto

Page 6: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

azzeriamo tutto

Page 7: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

proviamo con un approccio scientifico

Page 8: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

1) terremoto 2) vulcano 4) topografia 5) età del fondale oceanico

cosa dobbiamo conoscere: 4 concetti

Plate Tectonics

Page 9: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Basics

Plate Tectonics

terr

emot

o

Page 10: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Basics

Plate Tectonics

vulc

ano

Page 11: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Basics

Plate Tectonics

topo

graf

ia

Page 12: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Basics

Plate Tectonics

età

dei f

onda

li oc

eani

ciCampo magnetico

terrestre

Page 13: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

A questi 4 concetti facciamo corrispondere 4 gruppi di DATI

Plate Tectonics

Page 14: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

1) Terremoti: posizione e profondità 2) attività vulcanica recente: posizione 3) età fondale oceanico 4) batimetria e altimetria

Plate Tectonics

Page 15: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

2 x Vulcanologi

2 x Geofisici

2 x Paleomagnetisti

2 x Geografi

Ora dividetevi in 8 gruppi

Page 16: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Descrivete le caratteristiche dei DATI

Plate Tectonics

Avete a disposizione 30’ per

- descrivere i dati

- usando i fogli da luci - NON ROVINATE MAI I DATI - cercando di semplificarne la distribuzione e le caratteristiche principale

Page 17: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

COME?

> PUNTI

> LINEE

> CLUSTER/AREA

SOLI TERMINI da utilizzare per la descrizione

Page 18: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Ora mescolatevi

Plate Tectonics

GRUPPI MISTI con SIMOLOGI+

VULCANOLOGI+ PALEOMAGNETISTI+

GEOGRAFI

PORTATEVI DIETRO IL VOSTRO LUCIDO e iniziate a DISCUTERE

Page 19: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

- 4 overlaps - 3 overlaps - 2 overlaps - singularities

Page 20: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Cosa avete individuato?

Plate Tectonics

Quali sono le caratteristiche principali?

Possiamo addentrarci nei processi?

proviamoci

Page 21: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Locate plates boundaries

Plate Tectonics

Page 22: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

SEISMICITY

Tettonica delle Placche

depth red=0-33km orange=33-70km green=70-300km blue=300-700km

Page 23: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

VOLCANIC ACTIVITY

Tettonica delle Placche

Page 24: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO SECONDA RIGA NOME DIPARTIMENTO

VOLCANIC + SEISMIC

Tettonica delle Placche

Page 25: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

TOPOGRAPHY

Tettonica delle Placche

Page 26: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO SECONDA RIGA NOME DIPARTIMENTO

VOLCANIC + SEISMIC

Tettonica delle Placche

Page 27: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

AGE

Tettonica delle Placche !!! Note the maximun sea floor age with respect to the Earth’s age

180Ma

Page 28: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO SECONDA RIGA NOME DIPARTIMENTO

VOLCANIC + SEISMIC

Tettonica delle Placche

Page 29: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

Page 30: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

Page 31: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

What can we say about all this?

Here comes the Plate Tectonics

Page 32: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

Page 33: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

Page 34: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

può bastare?

Page 35: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

Page 36: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

adesso basta!

Page 37: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

alla prossima….

Page 38: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

GPS (Global Positioning System) is used to record plate motion

http://sideshow.jpl.nasa.gov/mbh/all/images/global.jpg

Page 39: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

We can follow all the horizontal movements of the plates

Page 40: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography of sea floor

We used several data to validate the theory

Page 41: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

What can we say about vertical movements

introduced by Plate Tectonics Theory?

mantle depth paths are needed

Page 42: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

DIGITARE NOME DIPARTIMENTO

SECONDA RIGA NOME DIPARTIMENTO

Seismic

Tettonica delle PlaccheTettonica delle Placche

Rosso=0-33km Arancione=33-70km Verde=70-3

TONGA TONGA

Page 43: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography
Page 44: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

convergent margins (distructive)

divergent margins (costructive)

Plate boundaries types

Page 45: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

Divergent margins (oceanic ridge)

Convergent margin (subduction/

collision)

Oceanic crust

Continental crust

Plate boundaries types

Page 46: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

Divergent margins (from continents to oceanic ridges) Constructive margins

a single plate

two plates

diffuse production of a new lithosphere

RIFTING

DRIFTING

/SPR

EADINGPlate boundaries types

Page 47: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Divergent margins (from continent to oceani ridges) constructive margins

Plate boundaries types

Page 48: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Divergent margins (oceanic ridges) -> constructive

Plate boundaries types

Page 49: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

What are the speeds of growth/drifting of the oceanic ridges?

Page 50: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

Oceanic crust

Continental crust

Plate boundaries types

Divergent margins (oceanic ridge)

Convergent margin (subduction/

collision)

Page 51: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate boundaries types

Plate Tectonics

Convergent Margin (subduction)

DISTRUCTIVE

Page 52: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Convergent Margin (subduction)

DISTRUCTIVE

Plate Tectonics

Page 53: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

Convergent Margin (subduction)

DISTRUCTIVE

Page 54: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica 2009-2010 54

1

1

2

2

3

3

4

5

6

7

6

8

5 8

highly simplified!!4

7

Rocks are able to tell us the subduction history

Page 55: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

Convergent margin:

subduction-collision

http://basalt.geology.utoronto.ca/tectonicslab/Subduction.html

if wifi available

Page 56: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Tettonica delle Placche

Transcurrent margins - conservative

Page 57: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

SanAndreasFault(USA)

Transcurrent margins – conservative

Page 58: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Plate Tectonics

Transcurrent margins - conservative

Page 59: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

Faults and plate boundaries

constructive margin

distructive margin

conservative margin

Plate Tectonics

Page 60: Tettonica delle Placche - unimi.it · Tettonica delle Placche 1) location and depth of the earthquakes 2) location of recent volcanic activity 3) sea floor age 4) Batymetry and topography

[email protected]

Plate Tectonics