The continent they think the continets were once all a part of?
Who had the continental drift idea in 1915?
What evidence was found proving that the continetal drift happened?
fossils rocks and mountain ranges
the shape of the coastlines were evidence
How was the ocean depth determined?
technology using sound waves
Best fossil evidence of animals?
How were the fossils found to be evidence?
It was believed the living things fossils were distributed
What could Wegner not explain?
He could not explain how they split apart
How did Wegner say htey split apart?
He said the seafloor seperated
Mid ocean ridge
system of mountain ranges on seafloor seperated by valleys
Who provided the idea of mid ocean ridge?
What did Hess think the magma did?
He thought the magma is buoyant and rises upward through the cracks in the crust
long narrow depression
What was the evidence on the seafloor?
rocks and sediments
What happened when the rocks hardened?
magnetic property spread along the floor
What was the plate tectonics theroy?
Earths surface is made of slabs of rigid rock that move over Earths upper mantle
What makes up the bottom part of the plate?
Solid layer of mantle
What makes up the top mantle?
Convergent plat boundaries
where the plates dive underneath eachother
transform plate boundary
collective movement of ensembles of molecules within fluids (i.e. liquids, gases) and rheids. It cannot take place in solids, since neither bulk current flows nor significant diffusion can take place in solids.
Convective heat transfer is one of the major modes of heat transfer and convection is also a major mode of mass transfer. Convective heat and mass transfer take place through both diffusion
proposed mechanism for plate motion in plate tectonics. Because mid-ocean ridges lie at a higher elevation than the rest of the ocean floor,
tectonic plate motion due to higher densities
most popular gas thats erupted
runny lavas viscosity
cinder cone volcanoes
small, short eruptions
broad falt structures composed of layers of lava low viscosity flow
large, steep shield, layers of lava and ash
forms above hot spots
earths outer core
crust and uppermost mantle combined
tectonic plates move on top of the upper mantle
what happens when pressure increases to the rock?
melting point of rock increases
liquid stored inside the earth
what happens when magma is forced upward?
causes a split in the rock
what happens when magma reaches the surface?
causes a volcano
areas of volcanic activity where magma moves towards earths surface
measure of fluid resistance to flow
flow more slowly
common in magma SiO2
solid material that erupts from a volcano
sudden movement or vibration of the ground that occurs when rocks slip and slide
where earthquakes occur
in tectonic plate boundaries
what percent occur along plate boundaries?
what occurs when energy is realesed?
forces applied to rocks along plate boundaries cause
object is squeezed or shortened
stretched or lengthened
different parts move in different directions
object is stressed
material changes shape as a stress is applied
crack in earths crust
sudden release of strain energy as rock moves along a fault
point of origin of a earthquake
directly above the focus
fastest travel through solids and liquids
slower only through solids
only travel on the surface from side to side
measures energy realesed during an earthquake , measures amplitude
ranks earthquakes on intensity and amount of damage
damage is the greatest when
it is near the epicenter
what materials are the strongest
the ones that bend
what do seismic waves do?
help scientists investigate the earth
when waves chaneg speed they aslo can
change that causes a wave to bend and change direction
boundary between two layers of material that have different density
what are discontinuity identified by
areas on earths surface where no seismic waves are recorded
when do shadow zones occur?
shadow zones occur when s waves cant travel through earths outer core