Other paleogeographic features change very rapidly and, therefore, any map, at best, is an approximation.
In this regard, the Earth, since the early Precambrian, has been divided into deep ocean basins (average depth 3.5 km) and high-standing continents (average elevation about 800 meters).
The similarity or dissimilarity of faunas and floras on different continents can be used to estimate their geographic proximity.
The second goal is to illustrate the changing distribution of mountains, lowlands, shallow seas, and deep ocean basins through time.
The past positions of the continents can be determined using the following five lines of evidence: paleomagnetism, linear magnetic anomalies, paleobiogeography, paleoclimatology, and geologic history.
The study of paleogeography has two principle goals.
The first goal is to map the past positions of the continents.
Continental lithosphere, because it is less dense, is more bouyant and is not easily subducted, or recycled back into the Earth's interior.
As a result, continents are made-up of very old rocks, some dating back 3.8 billion years.
Certain kinds of rocks form under specific climatic conditions.
For example coals occur where it is wet, bauxite occurs where it is warm and wet, evaporites and calcretes occur where it is warm and dry, and tillites occur where it is wet and cool.
Fluctuations, or "anomalies", in the intensity of the magnetic field, occur at the boundaries between normally magnetized sea floor, and sea floor magnetized in the "reverse" direction.
The age of these linear magnetic anomalies can be determined using fossil evidence and radiometric age determinations.
In contrast to the continents and ocean basins, which are permanent geographic features, the height and location of mountain belts and the shape of the Earth's shorelines constantly change.