plate tectonics, rock identification, scientific investigations

theory continental drift

states that Earths continents were once joined together in a single supercontinent and have slowly moved to their current positions over millions of years

pangaea

a single supercontinent that brought all of Earths landmasses together in one giant landmass

gondwana

evidence supporting continental drift

• jigsaw puzzle fit - they fit like a puzzle piece

• similar fossils found on different continents

• matching rock formations and mountain ranges

tectonic plates

massive, rigid slabs of solid rock that make up Earth's lithosphere

convergent - plate boundary

plates move towards eachother (collide)

divergent - plate boundary

plates move away from each other (depart)

transform - plate boundary

when plates slide past each other

fault

a fracture in the Earths crust where blocks of rock have moved past each other

tectonic activity in San Adreas Fault, California

Transform boundary involving strike-slip movement

tectonic activity in Himalayas, Asia

Convergent boundary where continental plates collide

tectonic plate activity in Iceland

Divergent boundary where plates move away from each other

tectonic plate activity in New Zealand

Convergent boundary where plates move towards each other

tectonic plate activity at the Mid-atlantic Ridge

divergent boundary where new oceanic crust forms

whats seafloor spreading?

a geoloical process where tectonic plates pull apart from each other at divergent plate boundaries