Science Chapter 5 Sudy Guide

continental drift

Wegner's idea that the continents began to slowly moved over Earth's surface became known as...

Pangea

What is the name of the supercontinent said to exist 225 million years ago?

states that earth's plates are in slow, constant motion, driven by convection currents in the mantle

What is the theory of plate tectonics?

That all the continents were once one large landmass

What was Werner's hypothesis about the continents?

Wegener could not name the force that pushed and pulled the continents

Why did geologists not accept Wegener's theory?

fossil

any trace of an ancient organism that has been preserved in rock

faults

break in earth's crust where rocks have slipped past each other- form along these boundaries

no

can crust be created or destroyed at transform boundaries

plates to move

convection currents in earth's mantle cause...

the collision squeezes the crust into high mountain ranges

describe what happens when 2 plates carrying continental crust collide

The denser plate subducts below the other at deep ocean trench

describe what happens when 2 plates carrying oceanic crust collide

The denser oceanic plate subducts below the continental plate

describe what happens when a plate carrying a oceanic crust collides with a plate carrying continental crust

plates

earth's lithosphere is broken into pieces separated by cracks. these pieces are called...

plate tectonics

interaction of the earths rigid ;lithosphere plates as they slide slowly the asthosphere

mid-ocean ridges, where new crust is added during sea-floor spreading

most divergent boundaries occur along

convection currents in the mantle

plate tectonics are driven by...

convergent boundary

plates come together, or converge, at a...

divergent boundary

plates move apart, or diverge from each other at a...,

transform boundary

plates slip past each other along a...

subduction

the process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle again

sea-floor spreading

the process of mid-ocean ridges continually adding more crust and old rock moving outward from the mid ocean ridge

the size and shape of the oceans

the processes of subduction and seafloor spreading can change...

volcanoes, mountains, earthquakes, and islands

what do convergent boundaries form?

crust is created here

what do divergent boundaries do to the crust?

rift zones, mid-ocean ridges, sea floor spreading

what do divergent boundaries form?

great changes in earths's surface and on the ocean floor. this also includes the formation of volcanoes, mountain ranges, and deep-ocean trenches

what do movements in plate boundaries cause?

the crust is neither created or destroyed here

what do transform boundaries do to the crust?

earthquakes

what do transform boundaries form?

it destroys the crust

what does convergent boundaries do to crust?

the formation, movement, and subduction of earth's plates

what does plate tectonics explain?

Rift Valley

where pieces of earth's crust diverge on land, a deep valley called a ___________________ forms

Continent

A single landmass is called a...

Farther away the rock was from the ridge, the older it was

How does evidence from drilling samples support mid-ocean ridges?

They line up with Earth's magnetc poles

How does evidence from magnetic strips support sea-floor spreading?

Pillow rocks, wich form only when molten material hardens quickly after erupting under water.

How does evidence from ocean floor material support sea-floor spreading?

deep-ocean trenches

-Places where the ocean floor plunges into deep underwater canyons

mid-ocean ridges

-Seams formed mountain ranges that ran along the middle of some ocean floors -form long chains of mountains that rise up from the ocean floor

sonar

-a device that uses sound waves to measure the distance to an object -used to map mid-ocean ridges

fossils from warm or cool climates may be found in the opposite climate area

How did evidence from climate support Werner's Pangea theory?

Fossils have been found in landmasses separated by oceans

How did evidence from fossils support Wegner's Pangea theory? ex: (Glossopteris)

Some landmasses, such as mountains, line up in separate continents

How did evidence from land features support Wegener's Pangea theory?