Download Pangaea (240 Myr ago) - University of Hawaii

Garrett Apuzen-Ito
Professor of Geophysics
Department of Geology & Geophysics
SOEST, University of Hawaii-Manoa
Objectives:
I. Our Dynamic Earth
Expressed through the
1) Overview plate tectonics & Earth’s major forms of volcanism
Creation of the Philippine Archipelago
2) Summarize origin & evolution of the Philippine Archipelago
Plate Tectonics
The rigid outer shell of the Earth, called the lithosphere, is broken up into many rigid
segments of different sizes and shapes.
Plate Tectonics
First evident in the continent jigsaw puzzle
Present
Day
Pangaea (240 Myr
ago)
Plate Tectonics is the Surface Expression
of Mantle Convection
Upper mantle
Hot (~3000 oF),
Ductile but
(mostly) solid
seafloor
spreading
subduction
subduction
How Fast Do the Plates Move?
seafloor
spreading
Sloooowly: 1-10 cm/yr
subduction
subduction
How Long Did it Take to Create the Pacific
Basin?
seafloor
spreading
That’s about 100 Million yrs!
At 10 cm/yr & life
A 1000 x 1000
Atime
1000
ofhuman
100 yrs
life
human life times
times
how much
givesfinger
10km
gives 10,000km
nail is grown? 10 m
1-10 cm/yr
subduction
subduction
Three Main Origins of Volcanism
Mid-ocean ridge volcanism
creates the seafloor.
60% of Earth’s surface!
Three Main Origins of Volcanism
Three Main Origins of Volcanism
Arc volcanism behind
subduction zones.
“Pacific Ring of Fire”
Tectonic Environment of the Philippines
How to Prepare for your Talk
1) Collect and learn your material
2) Decide on your main points
3)Prepare slides that start lead your
forward towards your main points
4) Practice (for effect, timing, performance)
5) Adjust your slides appropriately
6) Practice out loud to yourself