What name did scientists give to the huge ancient land mass that once contained all the smaller continents?

Answer

Pangea. This is part of the plate tectonic theory.

Answer

When all the continents are connected, it's called a supercontinent. There have been multiple supercontinents in Earth's history.

Alfred Wegener theorised that there was originally a super continent he named Urkontinent which existed before the continents were seperated and moved into their current locations. He come up with this theory in 1912. In 1928 the term Urkontinent was changed to the name we know today Pangaea or Pangea.

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