THEORY OF PLATE TECTONIC PLATES

2nd lesson idk !

Alfred Wegener

Father of theory of tectonic plates

Transform boundary

plates slide past

transform boundary

earthquakes

convergent boundary

plates collide, mountains and volcanoes form, new crust forms

divergent boundary

plates move away from eachother

continental drift theory

continents were once joined together and have since drifted apart

evidence of continental drift

fit of continents, fossils of same species, similar rock formations

plate tectonic theory

explains movements and interactions of earth’s lithosphere divided into tectonic plates

cause of tectonic plate movement

convection current in earth’s mantle

speed of tectonic plate movement

2 to 10 cm per year

oceanic-oceanic convergence

subduction when 1 of 2 plates is descending beneath the other

oceanic-continental convergence

subduction occurs, trench and volcanic arcs form, produces mountains and volcanoes

subduction

when 1 of 2 plates is descending beneath the other

continental-continental

collision forms fold mountains like Himalayas, shallow earthquakes but no volcanoes

transform plate boundary

occurs when two plates slide past eachother horizontally, opposite directions or same directions or different speeds