Answer:
Where the crack is formed a new subduction zone slowly develops.
Step-by-step explanation:
Tectonic plates are the pieces of the earth. If the distance between some parts of the earth becomes wide, the tectonic plate can crack. This is a way how the Himalayas are formed. These cracks can be easily seen as they are under the water.
Cracks can also be caused by earthquakes. In those cracks, the tectonic plates are touching. If they crash the pressure between the plates is big and they start to crack.