What is the name of this kind picture, a vertical cut of some object or terrain

It is a cross section. Merriam-Webster:

1a : a cutting or piece of something cut off at right angles to an axis also : a representation of such a cutting

...

3 : a composite representation typifying the constituents of a thing in their relations

Here is a cross section of the Earth from USGS. Notice that the section looks as if the Earth were sliced along a vertical axis:

enter image description here