This single continent broke apart over the course of millions of years. Eventually its constituent parts settled into a formulation that was known as "Classic Earth". (TV: The End of the World) This "version" of the planet had seven continents: Antarctica, South America, North America, Europe, Asia, Africa and Australia.
In a parallel universe, the Conclave was a super cabinet designed to ensure world peace which was composed of the leaders of Earth's five continents. The leader of the Republic of Great Britain represented Europe, the President of the American Confederation represented the Americas while White Russia, the Asian Co-Prosperity Sphere and India each had their own representatives. (PROSE: The Face of the Enemy)
By the year 200,100, the Earth had either a different continental arrangement, or different names for the "Classic Earth" formation. During the Battle of the Game Station, Dalek ships bombed and devastated these continents, which had names like Europa, Pacifica, the New American Alliance and Australasia. (TV: The Parting of the Ways)
Major planets Edit
Aside from Earth, there were some planets with which the Doctor or his companions had repeated contact. Thus detailed points about their continental arrangement was known.
On Skaro, the Thals and the Kaleds, later Daleks, lived on the same continent. (TV: The Daleks, Genesis of the Daleks) Another account held that the Thals lived on the continent of Davius, and the humanoid Daleks lived on Dalazar. (COMIC: Genesis of Evil)
On Trion, the main continent, home to the Trion, was divided into several regions, among them Ohwrotco, Noved, Dnalvelc, Norring, and Tronna. An impossibly vast chasm called the Giant's Drop was a popular tourist attraction. Another continent, Slotisland, was reserved for Trion's other native species, the Slots. Slotisland was home to the Slotsruins, traces of the vanished civilisation of the Laima, but the Slots kept the Slotsruins behind a force field to keep it secure from outsiders. Slotisland's secluded location, in the middle of an ocean that covered most of Trion's eastern hemisphere, was undoubtedly helpful in this regard. (PROSE: Turlough and the Earthlink Dilemma)
Minor planets Edit
Information about the continental formation of planets somewhat peripheral to the Doctor and his companions was occasionally gleaned.
On Whynot, the continents constantly changed on God's whim, including drowning a city (slowly and with due forewarning to the locals) because he heard about Atlantis. The two round continents of Lefteye and Righteye in the northern hemisphere, combined with the Grinning Archipelago on the equator, made the shape of a face from some angles. (PROSE: The Also People)