Subterranean.
buried
The Earth is round, and cities are located in different spots. As the Earth turns, different spots (cities) come under the Sun (daytime) and others are in the shadow of the Earth (nighttime).
Big man on campus
"Just under the wire", an expression meaning you barely made it.
Clay can be found on the surface in groups of varying number usually surrounded by Sand. It's usually found on a beach and under the water close to land.
Subterranean is defined as meaning lying under the surface of the earth. An example of this term would a subterranean river that is known to lie completely or almost completely under the surface of the earth.
Subterranian.
subterrainian of course
the crust is the surface of the earth
the plates under earth's surface
They are formed under the earth's surface.
'Magma' is melted rock occurring under the Earth's surface. When it comes up and flows out on the Earth's surface it is called 'lava'.
the surface of the earth
Magma is under the surface of Earth's crust. Rocks on earth's surface are well ... on Earth's surface. Magma is also molten rock, not solid rock like the rocks on earth's surface.
Focus
Metamorphic rocks are often found deep under the earth's surface because metamorphic rocks form from heat and pressure. Therefore, they form while they are under the earth's surface.
the surface of the earth