Plate tectonics theory describes the movement of the Earth's lithospheric plates. The interactions at the boundaries between these plates result in major geological phenomena. There are three primary types of plate boundaries.
Step 1: Understanding the Question:
The question asks to identify the plate boundary where new oceanic crust is formed.
Step 2: Detailed Explanation:
Let's examine the processes at each type of boundary:
Convergent boundary: Plates move towards each other. This leads to the destruction of crust (subduction) or the formation of mountains.
Divergent boundary: Plates move apart from each other. As they separate, magma from the mantle rises to the surface, cools, and solidifies to create new oceanic crust. This process is known as seafloor spreading and occurs at mid-ocean ridges.
Transform boundary: Plates slide horizontally past each other. Crust is neither created nor destroyed. This is also known as a conservative boundary.
The creation of new crust is the defining feature of a divergent boundary.
Step 3: Final Answer:
Thus, new oceanic crust is created at a divergent boundary.