Seismicity and Plate Tectonics

Christa G. von Hillebrandt-Andrade

Puerto Rico Seismic Network, UPRM

Caribbean Training Course in Seismology and Tsunami Warnings St. Augustine, Trinidad & Tobago

June 25-30, 2007

Our Dynamic Earth

Global Distribution of Tsunamis

From NGDC

Global Distribution of Earthquakes

Global Seismicity and Tectonic Plates

Continental Drift

Continental drift was first proposed in 1912 by Alfred Wegener, a German Astronomer and Professor.

Fossil Evidence

Mesosaurus is a freshwater reptile which could not possibly swim across the ocean from South America to Africa.

Fossil Evidence

Evidence from Rocks

Evidence from Paleoclimates/Glaciation

The orientation of rocks on several continents become consistent with those of a common ice-cap when they are re-assembled.

Keller, 2002

Plate Tectonics Evidence: Age of the Ocean Floor

Evidence: Magnetic Striping

From Kious and Tilling, USGS

Evidence for Plate Tectonics:Seismicity

Distribution of Seismicity Worldwide

Líneas de Costa, Límites Políticos

Circum-Caribbean SeismicityCircum-Caribbean Seismicity(1973-2006)(1973-2006)

NEIC (2006)

Age of Hawaiian volcanoes: Evidence for Plate Tectonics

Evidence for Tectonic Plate Theory: Earth Structure

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Plate Tectonic Forces

Break up of Pangaea

Source: Dietmar Muller, Sydney University

Lithospheric Plates

Global Plate Tectonic Activity

GPS Vectors in the Northeastern Caribbean

"Plate tectonic maps and Continental drift animations by C. R. Scotese, PALEOMAP Project (www.scotese.com)"

"Plate tectonic maps and Continental drift animations by C. R. Scotese, PALEOMAP Project (www.scotese.com)"

Plate Tectonic BoundariesPlate Tectonic Boundaries

Forces

Ductile Deformation

Brittle Deformation

Forces and Deformation

Divergent Boundary

Copywrite Tasa Graphic Arts

Fuerzas Tensionales

Fallamiento Normal

Océano

Falla de Transformación

Normal and Strike Slip Faults

Divergent Plate Boundaries

The Evolution of a Rift

East African Rift

Red Sea

Atlantic Ocean

Copywrite Tasa Graphic Arts

Continental Rift

Convergent BoundariesOceanic Lithosphere Subducting under

Oceanic Lithosphere

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Magma

Ascendente

Convergent Plate BoundaryOcean-Continent

Subduction as Generation Zones for

Tsunamis

Himalayan Orogeny

Convergent BoundariesContinent-Continent

Copywrite Tasa Graphic Arts

Transform Boundaries

Transform Boundaries

San Andreas FaultSan Andreas FaultW

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Strike-Slip Offsets

Map of Tectonic Plates

Caribbean Tectonic Setting

From ten Brink, USGS