Oceanography- Plate Tectonics
the person to propose the hypothesis of continental drift in 1911 was:
Wegener
the San Andreas fault:
a continental transform fault
Loihi excites geologists because it represents:
a new volcano that is the youngest in the Hawaiian Island chain
which of the following is characteristic of oceanic-continental convergent plate boundaries?
andesitic volcanoes
all continents fit together with the least number of overlaps and gaps when the continents are matched along:
contours at around 2000 meters in depth
possible cause for plate movements include:
convection currents in the mantle
which of the following is characteristic of oceanic-oceanic convergent plate boundaries?
volcanic island arcs
what is the name of the Mesozoic supercontinent that consisted of all of the present continents?
Pangea
how many lithospheric plates are there?
about 12
confirmation of seafloor spreading was supported by the:
age of seafloor
all the following provide evidence for continental drift except:
age of selection of continental rocks
a vast, underwater mountain chain is called:
an ocean ridge
which of the following is associated with convergent plate boundaries on the seafloor?
deep sea trenches and deep focus earthquakes
the mid-Atlantic ridge is an example of a:
divergent boundary
new crust is formed at trenches and old crust is subducted at ridges
false
the oldest rocks are located at mid-ocean ridge
false
water depth decreases as you move away from the mid-ocean ridge
false
the Hawaiian islands- emperor seamount chain was formed:
formed when the pacific plate moved across a hotspot
what evidence found on Africa and south America supports the hypothesis of continental drift?
fossils of the same plants and animals, the shapes of continental shelves match, and glacial deposits
at transform boundaries movement between the plates is:
horizontal, with plates moving past one another
moving from oceanic ridge to oceanic trench, the thickness of the lithosphere
increases in proportion to the distance
differences in height between continental crust and oceanic crusts are explained by:
isostasy
climate distribution on earth is primarily controlled by:
lattitude
continental drift was was confirmed through the use of:
location of magnetic poles through geologic time
the Hawaiian islands are located where the pacific plate is:
moving over a hotspot
youngest part of the ocean floor is found:
near ocean ridges
a strong positive magnetic anomaly is due to:
normal polarity during formation of ocean floor
transform faults:
offset spreading centers, can cut across continents, and involve horizontal movement
the seafloor magnetic pattern is best described as:
parallel to and symmetric about ocean ridge
fossils of ancient polar plants are currently found near the equator because the:
plants lived near the poles, but land masses ahve drifted to current locations
process in which an oceanic plate slides beneath a continental plate or another oceanic plate is known as:
subduction
deep ocean trenches are associated with:
subduction zones
which is true about the asthenosphere?
the asthenosphere is composed of outer mantle material
which is true about the lithosphere?
the lithosphere is composed of the crust and the topmost portion of the outer mantle
which of the following statements best describes the relationship between earths geographic and magnetic poles?
the magnetic pole wobbles, but stays near the geographic pole
oceans become deeper moving away from ridges due to:
thermal contradiction of hot asthenosphere
Iceland is geologically active because it sits above a hotspot and is located along the mid-Atlantic ridge
true
a rift valley is associated with divergent plate boundaries
true
deep focus earthquakes are often associated with deep-sea trenches
true
fast-moving spreading ridges tend to be more gently sloped than slow-moving ridges
true
continental-continental plate collisions produce:
very tall mountain ranges
