Why Are The Rocks At The Mid Ocean Ridge Younger Than Rocks Farther Away?

Where are the oldest rocks found?

Bedrock along the northeast coast of Hudson Bay, Canada, has the oldest rock on Earth.

Canadian bedrock more than 4 billion years old may be the oldest known section of the Earth’s early crust..

Does the age of the rock increase or decrease as you move away from the mid ocean ridge?

The age, density, and thickness of oceanic crust increases with distance from the mid-ocean ridge. The magnetism of mid-ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century.

What rocks form at mid ocean ridges?

Igneous rock is formed by the cooling and crystallization of molten magma at volcanoes and mid-ocean ridges, where new crust is generated. Examples of igneous rock are basalt, granite, and andesite (Fig.

What do you expect to find at mid ocean ridge?

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 two processes occur at mid ocean ridges?

There are two processes, ridge-push and slab-pull, thought to be responsible for the spreading seen at mid-ocean ridges, and there is some uncertainty as to which is dominant. Ridge-push occurs when the weight of the ridge pushes the rest of the tectonic plate away from the ridge, often towards a subduction zone.

Are there volcanoes at mid ocean ridges?

The vast majority of volcanic activity on the planet occurs along the mid-ocean ridge, and it is the place where the crust of the Earth is born. … The material that erupts at spreading centers along the mid-ocean ridge is primarily basalt, the most common rock on Earth.

What causes 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.

Why are mid ocean ridges elevated?

Since hot rocks are in a more expanded state and then contract as they cool (as they spread away from the ridge), the midocean ridges stand up high above the surrounding seafloor. The seafloor depth increases with distance away from the midocean ridges. The midocean ridges lie about 2.5 km below sea level.

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 an example of a mid ocean ridge?

Mid-ocean ridges form where two tectonic plates are pulling apart, also called seafloor spreading. … The Mid-Atlantic Ridge, which is spreading one to two inches a year, along with the East Pacific Rise, which is spreading two to six inches a year, are two examples of very long mid-ocean ridges.

Why are earthquakes shallow at mid ocean ridges?

Earthquakes along divergent and transform plate margins are shallow (usually less than 30 km deep) because below those depths, rock is too hot and weak to avoid being permanently deformed by the stresses in those settings.

How does the age of the rock change as you move away from mid ocean ridge?

As rocks crystallise from lava at the ridges, they literally record the magnetic field of the Earth at the time of their creation. … The two parts of the oceanic plate are pulled apart, and magnetic stripes become older as they move away from the mid-ocean ridge.

What happens to the rock along the ridge when new molten material erupts?

Applying Concepts What happens to the rock along the ridge when new molten material erupts? … As the molten material cools, it forms a strip of solid rock in the center of the ridge. When more molten material flows into the crack, it forms a new strip of rock.

Which feature of Earth is created at mid ocean ridges?

Explanation: 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.

Where is the oldest seafloor found?

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.

How does evidence that rocks farther from a ridge are older than rocks closer to the ridge?

The scientists found that the farther the rocks the older the rocks were,so the youngest rocks were found near the mid-ocean ridge. This showed that sea-floor spreading took place because that fact that rocks were because pushed out showed us that the sea-floor was spreading.

Which mid ocean ridge is spreading the slowest?

The Ridge is named after him, and the name was recognized in April 1987 by SCUFN (under that body’s old name, the Sub-Committee on Geographical Names and Nomenclature of Ocean Bottom Features). The ridge is the slowest known spreading ridge on earth, with a rate of less than one centimeter per year.

Which ocean is shrinking in size?

Pacific OceanSince subduction rates are much greater than the rates of producing new seafloor at the mid-oceanic ridges, simply because there are more spreading regions than subduction zones, the result is that the Pacific Ocean is shrinking on a geological time scale.

What types of lavas are erupted at mid ocean ridges?

Mid-Ocean Ridge Magmatism: By far, the dominant type of lava resulting from magmatic activity at mid-ocean ridges is basalt, also called mid-ocean ridge basalt (MORB). However, small amounts of other extrusive magma types (predominantly andesite, dacite, and picrite) also erupt there.

What is the mid Atlantic ocean ridge Why is it important?

Mid-ocean ridges are geologically important because they occur along the kind of plate boundary where new ocean floor is created as the plates spread apart. Thus the mid-ocean ridge is also known as a “spreading center” or a “divergent plate boundary.” The plates spread apart at rates of 1 cm to 20 cm per year.

Where is the youngest crust on Earth most likely located?

mid-ocean ridgeAnswer: The youngest crust on Earth is most likely located at the mid-ocean ridge.