Palaeogeography & Plate Tectonics

Question 1

What did land look like in the permian?

Answer 1

One large supercontinent known as Pangaea

Question 2

Alfred Wegner

Answer 2

German researcher who noticed in 1912 that coastlines of SA & Africa connected & that many of the same fossils could be found there.

Not until many years later that someone showed HOW continents could move.

Question 3

Layers of the earth

Answer 3

Crust - Outermost layer. Continents & oceans. ~5 - 25km deep.

Mantle - 2500 km deep. Uppermost portion is solid (in Lithosphere), lowermost portion is viscous slowly flowing solid (intense heat & pressure makes it malleable).

Core - Below mantle, primarily composed of nickel & iron. Two portions:

1. Outer Core: Molten liquid
2. Inner Core: Solid Ball, ~5700 *C

Question 4

Lithosphere

Answer 4

Composed of crust and uppermost portion of mantle.

Question 5

Asthenosphere

Answer 5

Portion of the mantle below the lithosphere (but not the rest of it!). Extreme heat of inner layers creates convection currents in the viscous asthenosphere. So, it heats, expands, rises then cools & sinks.

Question 6

Plates

Answer 6

Pieces of lithosphere affected by Asthenospheric currents.

Question 7

Plate Tectonics

Answer 7

Movements of the lithosphere. Explains drifting continents.

Studies of mid-ocean ridges show they’ve been slowly drifting apart. GPS can detect movements & record speed.

Question 8

Panthalassa

Answer 8

single super ocean surrounding pangaea