Earthquakes and Volcanoes

definitions about earthquakes and Volcanoes for science

crust 🌍

a layer of solid rock that includes both dry land and the ocean floor

mantle 🌎

the layer of the Earth located between the crust and the core,

inner core 🤎

it is a dense ball of solid metal

outer core 🌏

it is a layer of motel metal surrounding the inner core

convection current 🫖

the upward movement of warm fluids and the downward movement of cool fluids

tectonic plates 🍽

massive slab of solid rock made up of Earth's lithosphere (crust and upper mantle).

faults💔

they are breaks in the earth’s crust where rocks have slipped past each other

lithosphere 🤎

the uppermost part of the mantle

asthenosphere🤎

the soft middle layer in the mantle

lower mantle 🤎

the solid part of the mantle that is above the outer core

what is rock sample evidence ? 🪨

rocks drilled from deep inside the earth

what are seismic waves 🌊

earthquake waves

what are the 2 main types of evidence geologists used to tell about Earths surface? 🌎

direct evidence from rock samples 🪨& indirect evidence from seismic waves.

what does the oceanic crust made of / consist of 🌴

mostly basalt

what is continental crust made of 🏔

mainly granite

what metals is the core made of 🪙

nickel & iron

what is continental drift 🌎(Alfred Wegener)

the theory that at one time all the continents were together in one single landmass called pangea and have since drifted apart

what evidence supports the idea of continental drift 🌎

land features ie. mountain ranges lining up

fossil evidence ie. similar fossils found on different continents

climate change evidence ie. glacial scratches found in places with a mild climate now

why was Wegener’s hypothesis rejected 🤬

it was rejected because he could not provide an answer for how continents moved.

who suggested the idea of sea floor spreading 🌊

harry hess

what is sea floor spreading 🌊

as the sea floor spreads apart along both sides of a mid ocean ridge new crust is added

what evidence supports the idea of sea floor spreading 🌊

• molten material - pillow shaped rocks formed when molten material erupts and hardens quickly

• magnetic stripes - patterns in rock showing record of reversal’s in earth magnetic field

• drilling samples - father away from mid ocean ridges are older than ones that are closer

what was J.tuzo wilson’s theory 🧓

his theory was that the lithosphere was separated into different pieces called plates

what information did Wilson combine to combine to create his theory 🧓

• continental drift

• sea floor spreading

• earth’s plates

what does the theory of plate tectonics explain 🍽

it explains the formation, movement, and subduction of earth’s plates

what does theory of plate tectonics highlight 🍽

• plates float on top of the asthenosphere

• convection currents rise in the asthenosphere and spread out beneath the lithosphere

• convection currents cause the plates to move

• changes in earth’s surface include volcanoes mountains and deep ocean trenches

What does the theory of plate tectonics highlight about plates? 🍽

Plates float on top of the asthenosphere.

Convection currents cause the plates to move.

Convection currents rise in the asthenosphere and spread out beneath the lithosphere.

What changes in Earth's surface does the theory of plate tectonics explain?

Changes in Earth’s surface include volcanoes, mountains, and deep ocean trenches.