Geology Flashcards
Fault
a break in a rock structure causing a sliding movement of the rocks along the break
Folding
When rocks are pushing towards each other and cause a mountain or valley without breaking any rocks
Anticlines and synclines
Rocks that Bend up - anticlines
Rocks that bend down - synclines
Mantle
A thick layer in the Earths crust. The top is made out of molten magma while the rest is solid
Plate Tectonics
the theory concerning the movement of the continental plates
Convection Currents
circular movement that occurs when warmer, less dense fluid particles rise and cooler, denser fluid particles sink
Continental crust and oceanic crust
Continental - make up land
Oceanic - make up oceans
Subduction
process in which two tectonic plates push against each other, and oceanic crust sinks below the less dense continental crust
Destructive Plate Boundary
a convergent boundary where two plates collide
Constructive Plate
Plate that creates new land from cooling magma
Ocean Ridges
an area where the tectonic plates move apart, allowing magma from the mantle to rise, forming underwater volcanoes and creating new oceanic crust as it is cooled and solidified by sea water
Conservative plate boundaries
Slipping and sliding boundary
Pangaea, laurasia and Gondwanaland
Pangaea, The old super contitinent
When they split up, they formed
Gondwanaland - Africa, South America, Antarctica and australia
Laurasia - Europe, North America and Asia
Volcanoes
natural opening in the Earth’s crust connected to areas of molten rock deep inside the crust
Hotspot
Hotter spots in the crust/mantle which causes volcanoes to occur
Magma
Molten rock below the crust
Lava
Magma above the crust
Volcanic Bombs
Larger fragments which are ejected from the volcano. These fragments were causing the volcano to not erupt
Active, dormant and extinct volcanoes
Active - currently erupting
Dormant - hasn’t erupted in 20 years
Extinct- hasn’t erupted in 1000+ years
Alfred Wegener
Creator of the Plate Tectonics theory
Harry Hess
Created the theory of Seafloor Spreading
Sedimentary rocks and their types
Sedimentary
A rock that is made up layers that are natural.
Organic: made of organic matter, eg coal
Clastic: made of deposited layers, eg sandstone
Crystalline: made of a mineral but has a certain procedure done to it.
Fault or Transform Boundary
Fault:
A fracture in rock, due to pressure
When plates slide past each other, strike slip faults
When plates slide up and down, normal fault
When plates slide down and up, thrust/reverse fault
