A rift or chasm.
A ravine.
A ravine is a narrow, deep valley with steep sides typically formed by water erosion. It is often characterized by its rugged terrain and lack of vegetation.
A deep crack in Earth's surface is called a chasm. This term is typically used to describe a deep fissure or gorge that has been formed by natural processes such as erosion or tectonic activity.
A deep crack in the earth's surface is a fault It can also be a joint.
Groundwater is a supply of water that is stored beneath the earth's surface in saturated rock formations called aquifers. It is accessed through wells and boreholes for drinking water and irrigation purposes. Groundwater can be replenished through rainfall and infiltration.
a deep, steep-sided, narrow river valley
The deep narrow valleys on the Moon are called rilles. These are long, winding depressions that can stretch for many kilometers across the lunar surface. Rilles are thought to have been formed by a combination of ancient volcanic activity and tectonic forces.
The rock that churns deep beneath the Earth's surface is called "magma." It is a molten rock material that is located beneath the Earth's crust and can eventually rise to the surface as lava through volcanic eruptions.
continental shelf
igneous
A deep crack in the earth's surface is called a fault.
A fault.
A deep valley with steep sides would be called a gorge or canyon.
I have heard it called the rim.
There are more than one term for a deep narrow valley. Glens, canyons, ravines, fjords are terms you could use.
In oceanography, they are usually called "trenches".
Trenches, or deep sea trenches.