- How is seafloor created?
- What are 4 types of ocean floor?
- What causes plates to move?
- When did seafloor spreading start?
- Where do you expect to find the oldest seafloor material?
- Why is the ocean floor so difficult?
- Who discovered seafloor spreading?
- What is the strongest evidence of seafloor spreading?
- What is the average speed of seafloor spreading?
- How is paleomagnetism evidence of seafloor spreading?
- Did humans live on Pangea?
- What are the 4 steps of seafloor spreading?
- What is the cause of seafloor spreading?
- Is the ocean floor completely flat?
- What boundaries can destroy seafloor?
- What happens to the seafloor at trenches?
- Where is seafloor destroyed?
- How did Pangea look like?
- What caused Pangea to break up?
- What is the ocean floor called?
- Where is New seafloor created?
- What discovery about the ocean floor is associated with the seafloor spreading?
- What are the steps in the process of seafloor spreading?
- Did dinosaurs live on Pangea?
How is 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..
What are 4 types of ocean floor?
Lesson SummaryStudying the ocean floor is difficult because the environment is so hostile. … Features of the ocean floor include the continental shelf and slope, abyssal plain, trenches, seamounts, and the mid-ocean ridge.The ocean floor is rich in resources.
What causes plates to move?
The plates can be thought of like pieces of a cracked shell that rest on the hot, molten rock of Earth’s mantle and fit snugly against one another. The heat from radioactive processes within the planet’s interior causes the plates to move, sometimes toward and sometimes away from each other.
When did seafloor spreading start?
1960The seafloor spreading hypothesis was proposed by the American geophysicist Harry H. Hess in 1960.
Where do you expect to find the oldest seafloor material?
Mediterranean SeaThe Mediterranean Sea is home to what could be the world’s oldest oceanic crust, an undisturbed section of Earth’s outermost shell that scientists say is about 340 million years old.
Why is the ocean floor so difficult?
Why is much of the ocean floor so difficult to see? … In the movie, Tim says that ocean currents deposit sediment on the ocean floor.
Who discovered seafloor spreading?
Harry HessHarry Hess was a geologist and Navy submarine commander during World War II. Part of his mission had been to study the deepest parts of the ocean floor. In 1946 he had discovered that hundreds of flat-topped mountains, perhaps sunken islands, shape the Pacific floor.
What is the strongest evidence of seafloor spreading?
Several types of evidence supported Hess’s 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. This evidence led scientists to look again at Wegener’s hypothesis of continental drift.
What is the average speed of seafloor spreading?
approximately 5 centimeters a yearThe average speed of seafloor spreading is approximately 5 centimeters a year. This growth rate can be compared to the growth rate of human fingernails (Krupicka). The global ridge system consists of oceanic ridges. Seafloor spreading occurs at these elevated oceanic ridges and has high heat flow and volcanism.
How is paleomagnetism evidence of seafloor spreading?
Magnetic reversals show up as bands of alternating polarity in the slowly spreading seafloor. … This explanation of magnetic striping by paleomagnetism convinced scientists that new oceanic crust was being continually formed at mid-oceanic ridges. Seafloor spreading was accepted as a reality.
Did humans live on Pangea?
Pangea , the supercontinent existed approximately 335,000,000 (three-hundred thirty five) years ago. It would be impossible for any species that even slightly classify as humans to exist during the same time as Pangea did.
What are the 4 steps of seafloor spreading?
Terms in this set (7)Magma comes out of the rift valley.Magma cools to rock and hardens.Rock is pushed away as new rock is formed at MOR.Oceanic crust and continental crust meet at the trench.Oceanic crust bends down under the continental crust.Gravity pulls rock towards mantle.Rock melts to mantle.
What is the cause of seafloor spreading?
Sea-floor spreading is what happens at the mid-oceanic ridge where a divergent boundary is causing two plates to move away from one another resulting in spreading of the sea floor. As the plates move apart, new material wells up and cools onto the edge of the plates.
Is the ocean floor completely flat?
Before scientists invented sonar, many people believed the ocean floor was a completely flat surface. Now we know that the seafloor is far from flat. In fact, the tallest mountains and deepest canyons are found on the ocean floor; far taller and deeper than any landforms found on the continents.
What boundaries can destroy seafloor?
At convergent plate boundaries, oceanic crust is often forced down into the mantle where it begins to melt. Magma rises into and through the other plate, solidifying into granite, the rock that makes up the continents. Thus, at convergent boundaries, continental crust is created and oceanic crust is destroyed.
What happens to the seafloor at trenches?
Trenches are formed by subduction, a geophysical process in which two or more of Earth’s tectonic plates converge and the older, denser plate is pushed beneath the lighter plate and deep into the mantle, causing the seafloor and outermost crust (the lithosphere) to bend and form a steep, V-shaped depression.
Where 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.
How did Pangea look like?
Pangaea, which looked like a C, with the new Tethys Ocean inside the C, had rifted by the Middle Jurassic, and its deformation is explained below.
What caused Pangea to break up?
About 180 million years ago the supercontinent Pangea began to break up. Scientists believe that Pangea broke apart for the same reason that the plates are moving today. The movement is caused by the convection currents that roll over in the upper zone of the mantle.
What is the ocean floor called?
The seabed (also known as the seafloor, sea floor, or ocean floor) is the bottom of the ocean, no matter how deep. All floors of the ocean are known as ‘seabeds’.
Where is New 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 discovery about the ocean floor is associated with the seafloor spreading?
The magnetic history of the earth is thus recorded in the spreading ocean floors as in a very slow magnetic tape recording, forming a continuous record of the movement of the ocean floors. Other supportive evidence has emerged from study of the fracture zones that offset the sections of the ridge.
What are the steps in the process of seafloor spreading?
What are the steps in the process of sea floor spreading?Magma comes out of the rift valley.Magma cools to rock and hardens.Rock is pushed away as new rock is formed at MOR.Oceanic crust and continental crust meet at the trench.Oceanic crust bends down under the continental crust.Gravity pulls rock towards mantle.Rock melts to mantle.
Did dinosaurs live on Pangea?
Dinosaurs absolutely lived on Pangaea; in fact, scientists were able to confirm the existence of supercontinents in part because paleontologists found dinosaur fossils of similar/identical species of dinosaurs in locations that are now separated by oceans.