Quiz 1 | Chapters 1-3 Flashcards
What is a volcano?
An opening in the earth’s crust that allows materials that are warmer than their surroundings to escape from those surroundings
What is the escape of materials called?
An eruption
What form do these materials take?
Lava, ash, gas and other products
What is an earthquake
A sudden shaking of the ground caused by the sudden movement of part’s of the earth’s crust
Why is there breakage of the crust?
It can be due to a number of causes including volcanic activity
What is a hypothesis?
Conjecture that may explain observations and must have the possibility of being proven false
What is a theory?
An explanation that has been repeatedly tested and confirmed through observations and experiments
What is the crust?
Thin, outermost layer of the earth
What is the moho?
Marks boundary between crust and mantle
What is the lithosphere?
Consists of the crust and the uppermost part of the mantle, which is relatively rigid
Continental lithosphere is thicker than oceanic
What is the asthenosphere?
Lies below the lithosphere and entirely within the mantle with ability to flow like plastic
What is a seismoscope?
an earthquake detector using ball in a dragon’s mouth that falls into frog’s open mouth below.
When was/What happened during the Lisbon earthquake?
In 1755, there was a huge earthquake in Lisbon. All the people fled to the shore and then a tsunami hit and fires broke out all over town.
It significantly influenced enlightenment philosophers
Who is the father of modern geology?
James Hutton who believed in uniformitarianism which means “the past is the key to the present”
Who was Charles Lyell?
he was the first to link the occurrence of earthquakes with faults/breaks in the earth’s crust
What sorts of technological advances were made during the wars?
SONAR/Echo sounding was invented on submarines to test how deep the water was. This helped map out the mountains under the ocean
Magnetometers/Magnetic anomaly detectors: helped track the magnetic pole of the earth
The number of seismic stations increased because of nuclear fear
More scientists were on ships discovering stuff
Who came up with the idea of Continental Drift?
Alfred Wegener
What is the plate tectonic theory?
The lithosphere is divided up into rigid plates and the plates move above the asthenosphere.
Most of the relative motion between plates (and hence most geological activity) takes place along the relatively narrow boundaries between plates.
Interiors of plates are relatively stable
What is different about oceanic crust?
It is really dark and dense because of the amount of iron in it. It’s composed of salt and gabbro.
What do scientists look at to determine the direction of the magnetic pole?
the way iron faces when it cools on a volcano
Describe heat flow in underground volcano’s
heat from the mantle flows up through the crust. Heat flow decreases away from the ridge axis
Who came up with and what is Sea-floor spreading
Harry Hess came up with the idea. Robert Dietz coined the term.
volcanoes erupting push the crust out bringing up new crust. Old crust gets pushed down into the mantle
What are the three types of plate boundaries?
Divergent boundary
Convergent boundary (subduction zone)
Transform boundary
What is a divergent boundary?
as sea-floor spreading progresses, new oceanic lithosphere forms at the mid-ocean ridge axis.
These are the volcanoes in the ocean and where the heat flow comes up pushing old crust out and new crust up
