Seafloor spreading occurs
at divergent plate boundaries
. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor.
Where is seafloor created?
Seafloor spreading is a process that occurs at
mid-ocean ridges
, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.
What boundary creates new seafloor?
The Mid-Atlantic Ridge
is the longest mountain chain on Earth. These ridges are spreading centers or divergent plate boundaries where the upwelling of magma from the mantle creates new ocean floor.
How does seafloor created?
Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other,
heat from the mantle’s
convection currents makes the crust more plastic and less dense. The less-dense material rises, often forming a mountain or elevated area of the seafloor. Eventually, the crust cracks.
How is the seafloor made?
Bathymetry, the shape of the ocean floor, is largely a result of a process called
plate tectonics
. … Where plates diverge from each other, molten magma flows upward between the plates, forming mid-ocean ridges, underwater volcanoes, hydrothermal vents, and new ocean floor crust.
What boundary is seafloor destroyed?
You are correct that the seafloor is destroyed at
subduction zones
, but it is simultaneously being created at mid-ocean ridges. see figure 1 . Figure 1: Seafloor spreading at a mid-ocean ridge(where new crust is being created) and it’s destruction at a subduction zone.
What is a real life example of a transform boundary?
The most famous example of this is the San Andreas Fault Zone of western North America. The San Andreas connects a divergent boundary in the Gulf of California with the Cascadia subduction zone. Another example of a transform boundary on land is
the Alpine Fault of New Zealand
.
How old is the seafloor?
Scientists use the magnetic polarity of the sea floor to determine the age. Very little of the sea floor is
older than 150 million years
. This is because the oldest sea floor is subducted under other plates and replaces by new surfaces.
What rock is the seafloor made of?
The oceanic crust is primarily composed of
mafic rocks, or sima
, which is rich in iron and magnesium.
What are the features of seafloor?
Features of the ocean include
the continental shelf, slope, and rise
. The ocean floor is called the abyssal plain. Below the ocean floor, there are a few small deeper areas called ocean trenches. Features rising up from the ocean floor include seamounts, volcanic islands and the mid-oceanic ridges and rises.
What kind of rock is the seafloor made?
The seafloor is made of
volcanic rock
that solidified from magma and/or lava.
What are 4 types of ocean floor?
Features of the ocean floor include the
continental shelf and slope, abyssal plain, trenches, seamounts, and the mid-ocean ridge
.
What are the evidence of seafloor spreading?
Abundant evidence supports the major contentions of the seafloor-spreading theory. First, samples of the deep ocean floor show that
basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached
, and the sediment cover is thinner near the ridge.
Who discovered seafloor spreading?
Harry Hess
: One of the Discoverers of Seafloor Spreading.
What causes transform boundary?
The grinding action between the plates at a transform plate boundary results in
shallow earthquakes, large lateral displacement of rock, and a broad zone of crustal deformation
. Perhaps nowhere on Earth is such a landscape more dramatically displayed than along the San Andreas Fault in western California.
What landforms are created by divergent boundaries?
At DIVERGENT boundaries the plates move apart allowing molten magma to rise and form new crust in the form of ridges, valleys and volcanoes. Landforms created by divergent plates include
the Mid Atlantic Ridge and the Great African Rift Valley
.
