Tywin, Joffrey and Cersei of House Lannister
Tywin, Joffrey and Cersei of House Lannister: The Lannisters gained their immense wealth from the rise of the Mountains of the Moon HBO / Sky

If you're a massive fan of George RR Martin's Game of Thrones books and the HBO TV series, you might be interested in reading up about the geological history of the Westeros continent, as pieced together by Stanford University researchers.

Game of Thrones is a fantasy universe that explores social issues on a world where noble houses are engaged in a civil war for control over the Iron Throne of the Seven Kingdoms.

The Stanford researchers are a part of a project called Generation Anthropocene. They study the impact of human activities on the Earth's ecosystem and discuss what it means to be living in the current geologic age, the Anthropocene, which started 250 years ago.

Using official Game of Thrones maps, town names and character observations, together with geological principles learned from Earth, the researchers have reimagined 500 million years of evolution on the Game of Thrones planet, including ice ages, volcanos and continents rising from the oceans (see full geological map below).

House Lannister's wealth

For example, the researchers traced the wealth of House Lannister, who are currently in control of the Iron Throne, by looking at the geology described on the maps and comparing it to how the California Gold Country (where the Gold Rush took place from 1848-1855) was formed.

Between 80-100 million years ago, the Mountains of the Moon rose up in Westeros as the oceanic crust separating northern and southern Westeros subducted beneath the southern part of Westeros.

Since gold is formed on the ocean floor near mid-ocean vents, the heat and pressure of the oceanic crust subducting dissolved the gold, which solidified within quartz veins in rocks that were then mined by the Lannisters and is the source of their extensive wealth.

The researchers have also calculated that the Game of Thrones planet's radius is 4,297 miles, slightly larger than the Earth's radius of 3,959 miles, due to the fact that the distance between the Wall (which separates the Seven Kingdoms from the free folk) and the deserts of Dorne is 3,000 miles.

Khaleesi in the southern hemisphere

Westeros is believed to be located in the northern hemisphere, stretching out over an area from 30° to 66.5° latitude, as the area is cold enough to maintain the Wall of ice (probably near the arctic circle in our world) and prevent the White Walkers from attacking.

Game of Thrones
Daenerys Targaryen (Emilia Clarke) with her dragon Drogon. HBO/Sky Atlantic

Meanwhile following the current season, Game of Thrones Season 4, the Khaleesi, Daenerys Targaryen is currently near Meereen, the largest of the three great Slaver Cities. Daenarys is clearly in the southern hemisphere in a desert area similar to the Saharan Desert near Luxor in Egypt.

George RR Martin's depictions of the Slaver Cities are similar to Egypt, while the free cities outside the Wall bear a remarkable resemblance to the ancient city states of Italy and Spain, particularly the city of Braavos, which is described as a city made up of hundreds of tiny islands connected by stone bridges in a lagoon (Venice).

A Geologic Map for Game of Thrones
A Geologic Map for Game of Thrones Stanford University