The mantle =)
100
If you were 100 km below the surface you would be in the upper mantle / asthenosphere.
The layer of the Earth that is approximately 100 km below the surface is part of the upper mantle, specifically within the asthenosphere. The asthenosphere is a semi-fluid layer that lies beneath the lithosphere and plays a crucial role in plate tectonics and the movement of Earth's crustal plates.
The layer of the Earth that is roughly 100 km below the surface is part of the upper mantle called the asthenosphere. This region is characterized by its partially molten rock that allows for the movement of tectonic plates.
The Earth's lithosphere can vary in depth from 5 km at the ocean ridges to 200 km underneath mountain ranges.
The depth below the Earth's surface of the lithosphere varies depending on location, but on average it extends to about 100 kilometers (62 miles) deep. This layer includes the crust and upper part of the mantle and is characterized by its rigidity and brittle behavior.
The jet stream typically flows between 10 to 15 kilometers above the Earth's surface in the troposphere, the layer where most weather occurs. It can vary in altitude, moving up and down as it meanders around the globe.
The layer of the atmosphere with the coldest temperatures, reaching around -100 degrees Celsius, is the mesosphere. This layer extends from approximately 50 to 85 kilometers (31 to 53 miles) above the Earth's surface. Temperatures decrease with altitude in the mesosphere, making it the coldest atmospheric layer. It is situated above the stratosphere and below the thermosphere.
51
The asthenosphere begins approximately 100-200 kilometers below the Earth's surface and extends to about 700 kilometers deep. It is a semi-fluid layer of the upper mantle that allows tectonic plates to move and slide.
The pressure at 100 meters below the surface of sea water with a density of 1150kg is 145.96 psi.
The Lithosphere is the ridged layer of Earth that is about 100 km think and generally less dense than the material below it. This layer is the tectonic plates the move along on the anthesphere.