Science Test 2013-11-12 Flashcards
(30 cards)
What are Seismic Waves?
The waves that spread across the earth’s surface during an earthquake.
Wikipedia says:
Waves of energy that travel through the Earth’s layers during an earthquake, volcano…
What is the earth’s crust?
The surface layer of the earth.
(<1% of the volume of the earth.)
What is the earth’s mantle?
The layer of the earth just underneath the crust.
What is the outer core of the earth?
The layer just deep to the mantle.
What is the earth’s inner core
The part of the earth right in the middle;
It is deep to the outer core.
What is the earth’s lithosphere?
The crust and the uppermost mantle layers.
These are hard layers of the earth.
What is the Asthenosphere?
A part of the Upper Mantle just below the Lithosphere. Whereas the Lithosphere is hard,
the Asthenosphere is semi-molten.
The line dividing these two regions is 1300 degrees centegrade.
What is heat?
Thermal energy.
What is Conduction?
Spreading heat (in this case) by direct contact.
What is convection?
Heat moves by flowing mantle / fluid?
What is radiation?
Heat (or other energy) transferring with electromagnetic radiation (not with direct contact or with convection)
What is Pangaea?
Pangaea was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It was a single continent surrounded by ocean waters.
What is Laurasia?
Laurasia was the northern breakoff of the Pangaea supercontinent.
Laurasia became what is now North America and Eurasia (Eurasia is the combination of Europe and Asia)
What was Gondwana?
Gondwana was the southern portion of Pangaea
(after splitting from Laurasia)
What is Sea-Floor Spreading?
Volcanic activity adds to oceanic crust.
This moves the crust and results |in the sea floor spreading apart.
What are Ridges?
Underwater “mountain ranges” formed by volcanoes.
What are Trenches?
An oceanic trench marks the position at which the flexed, subducting slab begins to descend beneath another lithospheric slab.
What is subduction?
One Lithospheric plate decending below another.
What are plate tectonics?
Plate Tectonics is a scientific theory that describes the large-scale motions of Earth’s lithosphere. The lithosphere is broken up into 7 or 8 tectonic plates.
What are Faults?
A fault is a planar fracture in rock, across which there has been significant displacement along the fractures as a result of earth movement.
Faults are where most earthquakes occur.
What is a Transform Boundary?
Transform Boundaries are faults that neither create nor destroy lithosphere.
Relative motion is predominantly horizontal, end abruptly and are connected on both ends to other faults, ridges, or subduction zones.
Transform faults are the only type of strike-slip fault that can be classified as a plate boundary
What is a Divergent Boundary?
It is a linear feature that exists between two tectonic plates that are moving away from each other.
Divergent boundaries within continents initially produce rifts which produce rift valleys.
Most active divergent plate boundaries occur between oceanic plates and exist as mid-oceanic ridges.
Divergent boundaries also form volcanic islands which occur when the plates move apart to produce gaps which molten lava rises to fill
What is a Convergent Boundary?
In plate tectonics, a convergent boundary, also known as a destructive plate boundary (because of subduction), is an actively deforming region where two (or more) tectonic plates or fragments of lithosphere move toward one another and collide.
As a result of pressure, friction, and plate material melting in the mantle, earthquakes and volcanoes are common near convergent boundaries.
When two plates move towards one another, they form either a subduction zone or a continental collision.
What is Direct Evidence?
Supports a claim without need for any additional evidence or scientific inferences.
Example: Touching lava is direct evidence it is hot, and while your healing from what are significant burns you can watch it cool to form rocks.
