What are mid-ocean ridges primarily formed by?

Mid-ocean ridges are primarily formed by the upward movement and spreading of magma. This geological process occurs at divergent plate boundaries, where tectonic plates are moving apart. As the plates separate, magma from the mantle rises to fill the gap, creating new oceanic crust. This continuous upwelling of magma not only forms the underwater mountain ranges known as mid-ocean ridges but also contributes to the dynamic nature of the ocean floor.

The creation of mid-ocean ridges is closely related to the concept of seafloor spreading, where new crust is formed and older crust is pushed away from the ridge. This process is crucial for the growth of ocean basins and plays a significant role in the tectonic cycle, influencing global geology and oceanic ecosystems. Through this mechanism, mid-ocean ridges serve as important sites for both geological activity and the study of marine environments.