Table of Contents
- 1 What kind of magma does seafloor spreading generates?
- 2 What is formed by seafloor spreading?
- 3 What is the underwater mountain chain that is formed by the sea floor spreading called?
- 4 Where can you find seafloor spreading?
- 5 What is the importance of seafloor spreading?
- 6 What are the steps in the process of seafloor spreading?
- 7 Which type of crust is the oldest?
- 8 What are the seven major plates?
- 9 How did scientists discover the spreading of the ocean floor?
- 10 How is the East Pacific Rise different from the Mid Atlantic Ridge?
What kind of magma does seafloor spreading generates?
Seafloor spreading takes place at midocean ridges and produces basalt, the rock that makes up the oceanic crust. The Mid-Atlantic Ridge and East Pacific Rise are examples of midocean ridges. Midocean ridges reach a typical summit elevation of 2,700 meters below sealevel.
What is formed by seafloor spreading?
Seafloor spreading happens at the bottom of an ocean as tectonic plates move apart. The seafloor moves and carries continents with it. At ridges in the middle of oceans, new oceanic crust is created. Seafloor spreading helps explain continental drift in plate tectonics.
What is the underwater mountain chain that is formed by the sea floor spreading called?
A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of ~ 2,600 meters (8,500 ft) and rises about two kilometers above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a divergent plate boundary.
What rock forms the sea floor?
As old oceanic crust is subducted and melted into magma, new oceanic crust in the form of igneous rock is formed at mid-ocean ridges and volcanic hotspots.
What are the three types of sea floor spreading?
There are three types of plate-plate interactions based upon relative motion: convergent, where plates collide, divergent, where plates separate, and transform motion, where plates simply slide past each other.
Where can you find seafloor spreading?
Seafloor spreading occurs along mid-ocean ridges—large mountain ranges rising from the ocean floor. The Mid-Atlantic Ridge, for instance, separates the North American plate from the Eurasian plate, and the South American plate from the African plate.
What is the importance of seafloor spreading?
Significance. Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in the lithosphere.
What are the steps in the process 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 sea floor spreading and what causes it?
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.
What happens when two plates carrying continental crust collide?
Plates Collide When two plates carrying continents collide, the continental crust buckles and rocks pile up, creating towering mountain ranges. The Himalayas were born when the Indian subcontinent smashed into Asia 45 million years ago.
Which type of crust is the oldest?
Continental crust is almost always much older than oceanic crust. Because continental crust is rarely destroyed and recycled in the process of subduction, some sections of continental crust are nearly as old as the Earth itself.
What are the seven major plates?
There are seven major plates: African, Antarctic, Eurasian, Indo-Australian, North American, Pacific and South American. The Hawaiian Islands were created by the Pacific Plate, which is the world’s largest plate at 39,768,522 square miles.
How did scientists discover the spreading of the ocean floor?
The magnetism of mid-ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. Basalt, the once- molten rock that makes up most new oceanic crust, is a fairly magnetic substance, and scientists began using magnetometer s to measure the magnetism of the ocean floor in the 1950s.
How is the spreading of the seafloor a geologic process?
Seafloor spreading is a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other. Seafloor spreading is a geologic process in which tectonic plates—large slabs of Earth’s lithosphere—split apart from each other.
Why was rising magma important to plate tectonics theory?
This idea played a pivotal role in the development of the theory of plate tectonics, which revolutionized geologic thought during the last quarter of the 20th century. Rising magma assumes the polarity of Earth’s geomagnetic field before it solidifies into oceanic crust.
How is the East Pacific Rise different from the Mid Atlantic Ridge?
Rapidly spreading ridges have a much more gentle slopes. The Mid-Atlantic Ridge, for instance, is a slow spreading center. It spreads 2-5 centimeters (.8-2 inches) every year and forms an ocean trench about the size of the Grand Canyon. The East Pacific Rise, on the other hand, is a fast spreading center.