Science U4 L3 Mountain Building Flashcards
Strike-slip fault
fault blocks move past each other horizontally
Tectonic plate
a block of lithosphere that consists of crust
the rigid outermost part of the mantle
Describe how low viscosity eruptions effect how a mountain is created.
- flows easily
- forms low slopes
- erupts w/o large explosions
Hinge
the middle point of the bend in a syncline or anticline
What are the three kinds of faults?
- Strike-slip faults
- Normal faults
- Reverse Faults
T/F? There are underwater volcanoes.
True
Explain how a lava plateua can form
Lava can flow out of the entire length of the fissure. As a result, a thick and mostly flattened layer layer of cooled lava can form
What are the most common volcanoes along convergent plate boundaries?
Composite volcanoes
Anticline
the oldest layers of rock are found on the core of the fold, the youngest layers are found on the outside of the fold
What type of fault is San Andreas fault system?
Strike-slip fault
What is the boundary of a normal fault
Divergent
When the magma chamber below a volcano empties, the roof of the magma chamber may collapse and leave an even larger basin-shaped depression called _________________?
Caldera
What is the boundary of a reverse fault
Convergent
Volcanic ash
Small fragments of rock material that are ejected from a volcano
Lava
Magma that has reached Earth’s surface.
How are Reverse faults formed?
compression
Fault block
BLOCKS of rock on either side of the FAULT
What types of volcanic formations form at divergent plate boundaries?
Fissure eruptions
Shield Volcanoes
Fissure eruptions
Cidar Cones
What do you call a volcano in which an eruption has not occurred in a long time?
Dormant
How are strip-slip faults formed?
when rock is under shear stress
Where most divergent boundaries occur?
Ocean Floor (often forming underwater volcanoes)
What are the two kinds of folds?
Synclines & Anticlines
What can high temperatures do to rock?
allow rock to bend
Three kinds of Mountains?
- Folded Mountains
- Volcanic Mountains
- Fault-Block Mountains
What is the boundary of a strike slip fault
Transform
Fault
the crack that forms when large blocks of rock break and move past each other
a location where a column of extremely hot mantle rock, called a mantle plume, rises through the atmosphere
hot spot
This occurs when rock layers bend under stress.
Folding (bends are called folds)
Pyroclastic materials
hot ash and bits of rock
How are normal faults formed?
when rock is under tension
How does the movement of tectonic plates cause defomation in rocks?
It places stress on the rocks which changes the shape of the rocks.
How are folds classified?
based on the age of rock layers
Lava and clouds of ash can erupt from a ______, or opening of a volcano.
Vent
What determines the explosiveness of an eruption and the shape of the resulting volcanic mountain?
The viscosity
Describe how high viscosity eruptions effect how a mountain is created.
- does not flow easily
- forms steep slopes
- can erupt explosively
Inside the volcano, molten rock can form an expanded area of magma called __________________?
Magma Chamber
Stress
the amount of force per unit area that is place on an object
What can low temperature do to materials?
Make them more brittle or easily broken
Eruptions at hot spots commonly form what type of volcano
shield volcanoes
Composite volcanoes
- Alternating layers of hardened lava flows and pyroclastic material create composite volcanoes
- usually steep and large mountains
underwater mountain range
mid-ocean ridge
Shear stress
stress that pushes pushes rocks in parallel but opposite directions
Deformation
process by which rocks change shape when under stress.
Volcanic crater
an opening or depression at the top of a volcano caused by eruptions
Cinder cones
- ash & pieces of lava harden in the air and fall to the ground around a small vent. The hardened pieces of lava are called ciders
- a steep cone hill or mountain
shield volcanoes
-volcanoes w/ a broad base & gently sloping sides
-cover a wide area
-layers of lava flow out from the vent, harden & slowly build up to form the cone
-made of many layers
formed by quiet eruptions
What do you call the block above the fault plane?
hanging wall
Give two examples of mid-ocean ridges
East Pacific Rise
Mid Atlantic Ridge
How can a fault plane be oriented?
horizontally, vertically or at any angle in between
Fault plane
the location where two fault blocks meet
Given an example of folded mountains.
Pyrenees
Fissure Eruptions
- when lava flows from giant cracks, or fissures, in Earth’s surface
- has no central opening
What do you call the block below the fault plane?
footwall
Syncline
the youngest layer of rock are found at the core of a fold, the oldest layers are found on the outside of the fold
Normal fault
Hanging wall moves down relative to the footwall
The sudden movement of fault blocks can cause?
Earthquakes
the resistance of a liquid material to flow
Viscosity
List the volcanic landforms
shield volcanoes cider cones lava plateaus craters calderas
Volcano
Any place where gas, ash, or melted rock come out of the ground
Reverse Fault
hanging wall moves up relative to the footwall
Compression
stress that squeezes or pushes rock together.
What is the name used to describe the numerous explosive volcanoes that form on convergent plate boundaries surrounding the Pacific Ocean?
Ring of Fire
What is magma?
Melted rock that is less dense than solid rock
