the most abundant element in the earth's crust
What is oxygen
the two major kinds of folds
What are anticline and syncline
a volcano that is inactive but could erupt again
What is a dormant volcano
detect bulging causing the station to move
What is an inclinometer
detects volcanic earthquakes
What is a seismometer
the well known fault in Western California that geologists use to study elastic rebound
What is the San Andrea Fault
will probably not erupt again
What is a extinct volcano
magma hardens in a vertical fissure
What is a dike
magma squeezes between two horizontal rock layers and hardens
What is a sill
bend in the rocks of the crust caused by forces on the rocks
What is a fold
three scales that are used to describe an earthquakes strength
What is modified Mercalli scale, Richter magnitude scale and moment magnitude scale
thin outer layer made of solid rock
What is the crust
thick middle layer made of plastic rock divided into upper, lower manles and trasition zone
What is the mantle
center region of the earth; divided into outer core (liquid) and inner core (solid)
What is the core
a break in the rocks caused by forces on the rocks
What is a fault
scales used to measure the violence of a volcanic eruption
What is a Volcanic Explosivity Index
the belt where over half of the world's active volcanoes are found
What is the Ring of Fire or Circum-Pacific belt
three types of earthquake waves
What are P waves, S waves, Surface waves
the three types of volcanoes by composition of the cone
What are the cinder-cone, shield and composite
the major types of solid ejecta
What are pyroclasts, volcanic ash and lapilli
three major kinds of faults
What is the normal fault, strike-slip fault and the thrust fault
four types of igneous intrusions
What are dike, sill, laccolith and batholith
two main factors that determine the violence of an eruption
What is viscosity of the magma, amount of dissolved gas contained in the magma
three types of earthquake by depth
What is shallow-focus earthquake, intermediate-focus earthquake and deep-focus earthquake
a superheated cloud of gas and volcanic ash that travels down a volcano's slope as an avalanche
What is pyroclastic flow