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.
How does evidence that seafloor rocks farther from a ridge?
Explain how ocean floor data led early oceanographers and geologists to propose the hypothesis of seafloor spreading. ... By doing this, researchers found that the ages of the sea-floor rocks were also symmetrical on both sides of the ridge , with the youngest rocks near the center and the oldest rocks farther away.
What kinds of rocks are associated with 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. 7.57 A).
Why are rocks near the mid-ocean ridge younger than the rocks that are farther away from the mid-ocean ridge?
How did scientists discover that rocks farther away from the mid-ocean ridge were older that those near the ridge? Oceanic crust near the mid-ocean ridge is younger than the crust farther from the ridge. ... The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle .
What happens to the rocks that are farthest from the mid-ocean ridge?
Oceanic crust slowly moves away from mid-ocean ridges and sites of seafloor spreading. As it moves, it becomes cooler, more dense, and more thick. Eventually, older oceanic crust encounters a tectonic boundary with continental crust.
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.
What types of boundaries create mid-ocean ridges?
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 kind of magnetism do rocks right at mid-ocean ridges have?
When lava is extruded at any mid-ocean ridge, the rock it forms becomes magnetized and acquires the magnetic polarity that exists at the time the lava cools. As the crust moves away from mid-ocean ridges, it contains a continuous record of the Earth's changing magnetic polarity.
What happens to the age of rocks as you move away from ocean ridges?
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 are some examples of mid-ocean ridges?
Mid-ocean ridges are typically half a mile to six miles wide and over a mile underwater. Two of the most well-known mid-ocean ridges are the Mid-Atlantic Ridge and the East Pacific Rise . As you might guess, most of the Mid-Atlantic Ridge is in the Atlantic, and most of the East Pacific Rise is in the Pacific.
What type of rocks are in the ocean?
Chemical sedimentary rocks can be found in many places, from the ocean to deserts to caves. For instance, most limestone forms at the bottom of the ocean from the precipitation of calcium carbonate and the remains of marine animals with shells.
Are there earthquakes at mid-ocean ridges?
Since most of the mid-ocean ridge is more than 2000 meters deep, most of its eruptions go unnoticed. ... This region generating new ocean floor is also characterized by many small to moderate earthquakes .
What kind of lava is produced 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.
Where is the youngest crust on Earth?
Mapping and Dating the Least Known Part of Earth
The youngest crust of the ocean floor can be found near the seafloor spreading centers or mid-ocean ridges . As the plates split apart, magma rises from below the Earth's surface to fill in the empty void.
Are all rocks on the Earth formed in the mid-ocean ridges?
The answer to this question is no because most of the rocks are formed because of the aggregates of the mineral . Additionally, there are few layers like bedrock lander rocks also available on the earth.
Why are younger rocks found closer to divergent plate boundaries and older rocks found farther away?
Current research indicates that complex convection within the Earth's mantle allows material to rise to the base of the lithosphere beneath each divergent plate boundary. ... Because of this, rocks closest to a boundary are younger than rocks further away on the same plate.
