lesson three: volcano distribution & mountain ranges

mostly found along plate margins, which can be destructive / constructive boundary. also found in areas with subduction plates

where are volcanoes usually found?

subduction, collision of 2 plates

some volcanoes are formed through ___, which results from the ___

subduction

process in plate tectonics wherein the edge of one crustal plate descends below the edge of another

magma , volcano arcs

over time, ___ builds a series of volcanoes known as ___

pacific ring of fire

most of these volcanoes are found in an area called __

mountain ranges

formed due to movement of plates, even apart or toward each other. some are formed underwater

charles wyville thomson (1830-1882)

scottish marine zoologist who led the challenger expedition in 1872

the challenger expedition in 1872

what expedition did charles wyville thomson lead?

the mid atlantic ocean ridge formed by plates pulling apart

what ridge did thomson discover and how were they formed?

harry h. hess (1906-1969)

american geologist

harry h. hess (1906-1969)

proponent of seafloor spreading

harry h. hess (1906-1969)

in charge of the expedition & research about the ocean floor

not flat or smooth, but rough and full of land features

what did hess discover about the ocean floor’s texture?

the ocean floor is drifting apart causing these ocean floor fractures, which led them to conclude that the continents are moving apart

what did hess discover about the ocean floor’s movements?