when did plate tectonics begin on planet earth• the onset of plate tectonics is not an event, but...

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WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH ? Kent C. Condie Department of Earth and Environmental Science New Mexico Tech Socorro, NM 87801 USA

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Page 1: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

WHEN DID PLATETECTONICS BEGIN ON

PLANET EARTH ?

Kent C. CondieDepartment of Earth and Environmental Science

New Mexico TechSocorro, NM 87801 USA

Page 2: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3000

2800

2600

2400

220001.02.03.04.0

Time (Ga)

1018

1017

1016

1015Temperature

Viscosity

MANTLE EVOLUTION

Page 3: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some
Page 4: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some
Page 5: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

POSSIBLE PLATE TECTONIC RETURNS

1. Asymmetric Subduction 2. Symmetric Subduction

3. Plate Sinking

Page 6: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some
Page 7: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Distance (km)

Figure Courtesy of Steve Holbrook

New Continental Crust is formed in arcs

such as the Aleutian Arc

Page 8: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 9: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 10: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 11: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 12: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 13: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 14: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Pillow basalts

Andesites

Breccia

Felsic volcanics

Graywackes

Boninites

Melange

ISLAND

ARCS

Page 15: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.4

2.7Foreland Basins

Passive Margins

3.1Arcs

2.7

Continental Rifts3.0

1.0 2.0 03.0Ga

Page 16: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Accretionary Prisms

3.0 Ga 1.0 2.0 0

Page 17: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

2.7Foreland Basins

Page 18: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

DEVELOPMENT OF PASSIVE MARGINS

Page 19: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

Passive Margins2.7

Page 20: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some
Page 21: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

Continental Rifts3.0

Page 22: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

3.4Metallic Mineral Deposits

Page 23: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Accretionary Prisms3.1

Arcs

2.7Foreland Basins

Passive Margins2.7

Continental Rifts3.0

3.0 Ga 1.0 2.0 0

3.4Metallic Mineral Deposits

Page 24: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.3

Paired Metamorphic Belts

3.0 Ga 1.0 2.0 0

Subduction zones are coldSubduction zones are cold

Backarcs are hotBackarcs are hot

Page 25: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

Large Transcurrent Faults

3.2

Page 26: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

Accretionary Orogens

3.7

Page 27: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

Collisional Orogens

2.2

Page 28: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

PALEOMAGNETISM ALLOWS THE

RECONSTRUCTION OF SUPERCONTINENTS

SUCH AS GONDWANA SOME 600 Million years

ago

Page 29: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.0 Ga 1.0 2.0 0

Paleomagnetism3.0

Page 30: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

10

100

0 10 20 30

Zr/Nb

Nb/Th

DEP

NMORB

DM

EN

ARC

UC

EM2

HIMU

EM1

OIB

REC

PM

3.0 Ga 1.0 2.0 0

3.1Igneous Geochemistry

Arc type

> 3 Ga 1.0 Ga2.5 Ga

Non-Arc

type

Page 31: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

SEISMIC REFLECTION PROFILE EASTERN CANADA

Page 32: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Magnetotelluric data illustrate Magnetotelluric data illustrate

lithospheric mantle structure: frozen slabs?lithospheric mantle structure: frozen slabs?

Page 33: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

2.7 Deep Seated Geophysics

3.0 Ga 1.0 2.0 0

Page 34: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3.3

Paired Metamorphic Belts

Collisional Orogens

2.2

3.0 Ga 1.0 2.0 0

3.1Igneous Geochemistry

Large Transcurrent Faults

3.2Accretionary Orogens

3.7

Paleomagnetism3.0

2.7 Deep Seated Geophysics

Page 35: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

• Pi; Pillow Basalts from

the Troodos

Ophiolite , CyprusText

Page 36: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Blueschist with garnet from the Alps

courtesy of Jane Selverstone

Page 37: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Ultra-high pressure eclogite (garnet, omphacite, coesite)

courtesy of Mike Brown

Page 38: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

38

Page 39: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

3939

Page 40: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

40

Page 41: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

SUMMARY OF PLATE TECTONIC INDICATORS

3.4 -3.1 Ga

First

Appearances

2.7-2.0 Ga

Widespread

Distribution

Page 42: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

Symmetric Subduction

Steep Subduction

Plate Stacking

Delamination

> 4.5 Ga ?

3.0 - 2.0 Ga

4.5 - 3.0 Ga

eclogite

sinkers

Page 43: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

43

Stagnant

Lid

Episodic

Subduction

Modern

Subduction

I II III

After O’Neill et al 2007

Page 44: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

SUMMARY

• The onset of plate tectonics is not an

event, but an evolving process that

began locally by about 3 Ga.

• Plate tectonics, in some form, probably

existed on planet Earth from the

magma ocean stage onwards.

• Modern subduction became

widespread beginning about 2.7 Ga.

Page 45: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

AND HIGHER LIFE FORMS REQUIRE

CONTINENTS

and

CONTINENTS REQUIRE PLATE

TECTONICS

Page 46: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

IS THERE A RELATIONSHIP

BETWEEN LIFE AND PLATE

TECTONICS?

Life requires water and nutrients

But water and nutrients are

available on planets without plate

tectonics

Page 47: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

The Oldest Fossils occur

In the Marble Bar Chert in

Western Australia at 3.45 Ga

Modern hydrothermal vent

on the seafloor

Page 48: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

HOW CONTINENTS GROW

Page 49: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some

JUVENILE

CONTINENTAL

CRUST

2.5 Ga Southern

India

2.7 Ga Zimbabwe

4.0 Ga

Yellowknife

Canada

Page 50: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some
Page 51: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some
Page 52: WHEN DID PLATE TECTONICS BEGIN ON PLANET EARTH• The onset of plate tectonics is not an event, but an evolving process that began locally by about 3 Ga. • Plate tectonics, in some