The ancient distribution of these, and other, rock types can tell us how the global climate has changed through time and how the continents have travelled across climatic belts.In order to reconstruct the past positions of the continents it is necessary to understand the development of the plate tectonic boundaries that separate continents and bring them back together again.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.Because these magnetic anomalies form at the mid-ocean ridges, they tend to be long, linear features (hence the name "linear magnetic anomalies") that are symmetrically disposed about the ridges axes.The past positions of the continents during the last 150 million years can be directly reconstructed by superimposing linear magnetic anomalies of the same age.The carbon-14 method was developed by the American physicist Willard F. It has proved to be a versatile technique of dating fossils and archaeological specimens from 500 to 50,000 years old.
Once the organism dies, however, it ceases to absorb carbon-14, so that the amount of the radiocarbon in its tissues steadily decreases.
The similarity or dissimilarity of faunas and floras on different continents can be used to estimate their geographic proximity.
In addition, the evolutionary history of groups of plants and animals on different continents can reveal when these continents were connected or isolated from each other.
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 Earth's climate is primarily a result of the redistribution of the Sun's energy across the surface of the globe.