1Q: plate tectonics Flashcards
it is a theory that explains the different processes that cause formation of didferent geologic features and phenomena.
plate tectonics theory
a german meteorologist and geophysicist, hypothesized and suggested that the landmasses of Earth once merged a supercontinent
Alfred Wegener
the two continents after the separation
laurasia and gondwanaland
states that the earths lithosphere is composed of fragments or plates that interact with one another.
plate tectonics theory
the term tectonic came from the Latin word _____ or Greek word _____ which means to ____’
tectonicus, tektonikos, build
the outermost layer of the earth that is composed of the mantle and the crust
lithosphere
made of various types of rocks and sediments floating on top of the malleable upper mantle that extend from the surface to about 50km deep. it has a density of 2.6g/cm³
crust
thicker and less dense and floats
continental crust
denser and thinner
oceanic crust
the seven major plates
NA, SA, Eurasian, Indo-Australian, African, Antartic, Pacific
intermediate plates
philippine, Caribbean, cocos, nazca, scotia, juan de fuca, and arabian plates
the pacific plate moves for approximately ____
8cm or 3 inches
the north american llate approximately moves at
3cm ir 1 inch
around ___ of earthquakes are felt at plate margins
90%
these waves travel in the interior of the earth
primary and secondary waves
examples of surface waves
rayleigh waves and long waves
what is used to determine the epicenter of an earthquake
the difference in arrival time between the p and s waves
if three recorded measurements were done at different stations, _____ will be used to find its epicenter.
triangulation method
a scottish marine zoologist that led the challenger expedition in 1872
charles wyville thomson
the distribution of volcanoes is mostly found in plate margins which can be either:
constructive or destructive
when a plate goes underneath another
subduction
a series of volcanoes
volcano arc
most of volcano arcs are found here
pacific ring of fire
have been formed due to movements of plates, either apart or toward each other
mountains
is a american geologist that served in the military and became the major propronent of sea floor spreading
harry h. hess
a type of collision between two crustal plates. one plate to subduct from another.
oceanic-oceanic convergence
two continental crustal plates move toward one another. folding of parts in the continental lithosphere happens.
continental-continental convergence
move horizontally to each other
transform
another feature that results from movement
rift valley
oceanic crust is formed at mid-ocean ridges and spreads outwards
seafloor spreading
plate boundaries where the plates move apart from each other
divergent
type of collision between an oceanic crust and continental crust. oceanic crust becomes lighter than continental crust
oceanic continental convergence
a deep narrow depression in fhe ocean seafloor caused by the collision and/or subduction of plates
trench
brittle solid part of earth; made up of crust and mantle
lithosphere
density and thickness of continental crust
2.7g/cm³ and 35-70km
primary composition of cc
granite
denisty and thickness of the oceanic crust
3.0g/cm³ 7-10km
primary composition of oc
basalt
a ductile layer under the solid lithospehere
asthenosphere
other term for plate boundaries
plate margins
the seven continents
• north america
• south america
• antartica
• australia
• asia
• europe
• africa
part of the earth’s surface directly above the focus of an earthquake
epicenter
an apparatus to record vibrations within the earth and the ground
seismograph
vent or fissure in the planet’s crist in which laba, ash, rock, and gases erupt
volcano
measures the energy released at the source of the earthquake
magnitude
measures the strength of shaking produced by the earthquake at a certain location
intensity
plate boundaries that move toward each other
convergent
