Earth Science Flashcards
Mid Ocean Ridges:
Mountain Ridges on the ocean floor
Trenches:
Deep valleys in the ocean floor
Sea Floor Spreading:
The process of magma rising to the surface at mid ocean ridges to from new crust.
Theory of Plate Tectonics:
The lithosphere is broken into large plates that interact and cause geological events
Tectonic Plates:
Large plates that float slowly on a layer of fluid-like rock in the Earth’s Mantle
Divergent Plate Boundary:
When two tectonic plates move away from each other
Convergent Plate Boundary:
When two tectonic plates move towards each other
Transform Plate Boundary:
When two tectonic plates slide past each other
Mantle Convection:
the process of the mantle heating up and rising to the surface where it cools and sinks down once more, repeating the process
Earthquake:
Shaking of the
earth’s crust from a sudden
release of energy caused by
movement along faults
Fault:
Fractures (cracks) in the Earth’s
crust. They can be as small as a
few millimeters and as large as
several kilometers.
Focus:
The point where
breakage of rock inside
Earth first happens
Seismic wave:
an elastic wave in the earth produced by an earthquake or other means
Epicentre:
the point on Earth’s surface above where an earthquake starts (above the focus)
Seismographs:
instruments used to record the motion of the ground during an earthquake
Magnitude:
the size of an Earthquake
Volcano:
opening in Earth’s
surface where magma and
other materials are released
4 Aspects of Primary Waves:
Cause rock particles to move forward and backward
(compress and expand like an accordion),
Move the fastest,
Are the first ones detected
in an earthquake,
Can travel through liquids and solids (Earth’s
interior)
3 Aspects of Secondary Waves
Move slower than P waves, faster than surface waves, Causes rock particles to move up and down or side to side, Can only travel through solids
4 Aspects of Surface Waves
On the surface and often cause, the greatest damage Cause rock particles to move up and down, and side to side, Slowest of the three waves, Can travel along the surface of Earth (not through Earth’s interior)
What are the layers of the Earth and their order (Surface to Core)
Crust, Upper Mantle, Lower Mantle, Outer Core, Inner Core
Hot Spots:
hot regions of Earth’s
mantle where magma rises to the
surface by breaking through weak parts
of the lithosphere
Hot Spot Volcanoes:
Tectonic plates can move over fixed
areas called hot spots, creating a trail
of volcanic islands, Volcanoes can form above hot spots as the
magma rises and melts through the crust
