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 does seafloor occur and 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.
At which boundaries 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.
Where does most of the new seafloor form?
New seafloor is generated from the upper mantle at the mid-oceanic ridges , spreads laterally outward, and is eventually subducted, or consumed, at the margins of ocean basins. Subduction may also occur between two regions of oceanic crust, with older, denser sections underthrusting younger, less-dense ones.
Where does seafloor spreading occur quizlet?
Where does seafloor spreading occur? This process occurs along divergent plate boundaries at areas called mid-ocean ridges .
What causes seafloor to spread?
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.
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.
Where is the youngest seafloor located?
Where is the youngest ocean floor located? The youngest ocean floor is located on the mid-ocean ridge .
How old is the youngest seafloor?
Because of this correlation between age and subduction potential, very little ocean floor is older than 125 million years and almost none of it is older than 200 million years.
What is the first step of seafloor spreading?
1. A long crack in the oceanic crust forms at a mid ocean ridge . 2. Molten material rises and erupts along the ridge.
What is the seafloor made of?
The seafloor contains deposits of minerals that we use in everyday life such as copper, zinc, nickel, gold, silver, and phosphorus . These deposits occur as crusts on volcanic and other rocks and as nodules on abyssal plain sediment that are typically about 3 to 10 centimeters (1 to 4 inches) in diameter.
How does a new seafloor form?
Mid-ocean ridges occur along divergent plate boundaries, where new ocean floor is created as the Earth’s tectonic plates spread apart . As the plates separate, molten rock rises to the seafloor, producing enormous volcanic eruptions of basalt.
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 is evidence of seafloor spreading?
Abundant evidence supports the major contentions of the seafloor-spreading theory. ... Magnetic surveys conducted near the mid-ocean ridge showed elongated patterns of normal and reversed polarity of the ocean floor in bands paralleling the rift and symmetrically distributed as mirror images on either side of it.
What is one piece of evidence of seafloor spreading?
There is lots of evidence that proves that seafloor spreading is occurring. One piece of evidence is mid-ocean ridges . Rocks found near mid-ocean ridges are young and get older as the distance from the ocean ridge increases.
What are the three pieces of evidence for seafloor spreading?
What three types of evidence provided support for the theory of sea floor spreading? eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves.
