Читать книгу Geology For Dummies - Alecia M. Spooner - Страница 66

Many geologists study portions of the earth that can be seen. However, some of the most fascinating and still unanswered questions about the earth have to do with what is going on inside — beneath the rocks we can see and touch at the surface.

Humans do not yet have technology advanced enough to dig more than about 12 kilometers (about 7.5 miles) into the earth’s crust. So how do scientists know anything about the inside of the earth? They combine their observations of rocks on the surface with knowledge gained from laboratory experiments of temperature and pressure on different materials. Doing so gives them a pretty solid basis on which to make inferences about what occurs in places that can’t be directly observed.