Paleogeology is the historical geological state of a particular area, or the study of the geologic

Geology

Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...

 history and origins of the earth

Earth

Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

, including such things as reconstructions of previous configurations of the Earth's continents, the history and evolution of the Earth's surface geological configuration, the formation and development of continents, and so on.

There are several related fields of research that are involved in paleogeology, including Plate tectonics

Plate tectonics

Plate tectonics is a scientific theory that describes the large scale motions of Earth's lithosphere...

, which studies the history and movements of the Earth's continents.