Is this true? If not why?
Oceanic crust near the mid-ocean ridge is younger than oceanic crust farther away from the ridge?
Yes, it is true that oceanic crust near the mid-ocean ridge is younger than oceanic crust farther away from the ridge. This phenomenon is known as seafloor spreading, which is a key process in plate tectonics.
To understand why this is true, here's an explanation:
1. Mid-Ocean Ridge: The mid-ocean ridge is an underwater mountain range that extends throughout the Earth's oceans. It marks the boundary between tectonic plates where new oceanic crust is formed.
2. Seafloor Spreading: Seafloor spreading occurs when two tectonic plates move away from each other, creating a gap at the mid-ocean ridge. As the plates diverge, magma from the Earth's mantle rises up and fills the gap, solidifying to form new oceanic crust.
3. Age of Oceanic Crust: The rate of seafloor spreading varies, but on average, new oceanic crust is continuously forming at the mid-ocean ridge. As a result, the crust near the ridge is relatively young in comparison to crust farther away. The farther the crust travels from the ridge, the older it becomes, as it continues to move away from the site of formation.
4. Paleomagnetism and Age Determination: Scientists use various techniques to determine the age of oceanic crust. One widely used method is paleomagnetism, which involves studying the magnetic properties of the crust. As new crust forms at the mid-ocean ridge, it acquires the prevailing magnetic field of the Earth. By studying the patterns of magnetic polarity in the crust over time, scientists can estimate its age.
Therefore, based on the process of seafloor spreading and the gradual movement of tectonic plates, we can conclude that oceanic crust near the mid-ocean ridge is indeed younger than crust farther away from the ridge.