Vocabulary 1
What is liquefaction?
Occurs when wet soil acts more like a liquid during an earthquake
What is a caldera?
large depression formed when volcano collapses
What is the world's most active volcano? Where is it found?
Kilauea/Hawaii
What is a seismic safe structure?
built with flexible, circular morringsplaced under buildings. alternating layers of steel and rubber that act like a cushion
What is sill?
Igneous rocks formed when magma is squeezed into horizantal crack and hardens underground
What is a modified mercalli scale?
it describes the intensity of earthquake using the amount of structural and geographical damage in a specific location.
What is a crater?
steep walled depression around volcano's vent
How does a volcanic neck form?
1. magma hardens
2. erosion wears away
3. cone erodes leaving behind solid igneous core which is volcanic neck.
What are the three types of vaults and the stress at each?
Normal=Tension Force
Reverse=Compression Force
Strike-slip = Shear Force
What is tephra?
Rock or solidified lava dropped from air during explosive volcanic eruptions
What is the richter scale?
describes the strength of a earthquake based on height of lines on seismogram
What is cinder cone?
steep-sided, loosely packed volcano formed when tephra falls to the ground.
Where do volcanoes occur?
1. plates moving apart
2. plates moving together
3. hot spots
Where are hot spots?
boundary between Earths mantle and core/ most are in ocean
What is shiprock in New Mexico?
example of volcanic neck.
What is the liquid outer core?
made mainly of iron and it is between the inner core and lower mantle.
What is a dike?
igneous rock feature when magma is squeezed into vertical crack that cuts across rock layers and hardens underground.
What effect do silica and water have on volcano?
High silica and high water=high eruptive force
low silica and low water vapor = low eruptive force
high silica and low WV= moderate eruptive force
What is a vent?
opening where magma is forced up as lava forms the volcano.
What is volcanic neck?
solid igneous core of volcano left behind after softer cone has eroded
What is a batholith?
the largest intrusive rock body that forms when magma is being forced upward towards earths crust, cools slowly and then solidifies.
What is a hot spot?
result of an unusually hot area at boundary between earths mantle and core that forms volcanoes when melted rock is forced upward and breaks through the crust.
What is a shield volcano?
A broad gently sloping volcano formed by quiet eruptions of basaltic lava.
What is a volcano?
opening in earths surface that erupts sulfurous gases, ash and lava. Forms at plate boundaries