Final answer:
The name of the gigantic crack at the center of the spreading center is a mid-ocean ridge. This geological feature results from tectonic plates diverging and new crust being formed from rising magma.
Step-by-step explanation:
The gigantic crack on the floor at the center of the spreading center is known as a mid-ocean ridge. This feature is found where tectonic plates are moving apart, allowing magma from beneath the Earth's crust to rise and cool, forming new crust.
As a historical reference, the photograph of mudcracks taken by NASA's Mars Rover Curiosity on December 31, 2016, may look similar, but the mudcracks are a different geological feature than the mid-ocean ridges found on Earth.
These Martian mudcracks suggest that they may have formed more than 3 billion years ago, indicating the presence of water on Mars in the distant past.