You can get a much better fit together of the present continents to create the last supercontinent Pangea on a planet Earth, with the globe at 80% its present size.
H G Owen, Head of the Department of Palaeontology of the British Museum, in his book Atlas of Continental Displacement, 200 Million Years to the Present has recreated Pangaea using plate tectonics, seafloor spreading (new material from mid ocean ridges) and moving the continents on a smaller planet, 80% the size of the modern globe.
The continental rocks slip together to form a near perfect Pangaea, without the large gaps (gores) that appear if Pangea is formed using the same size planet Earth as we have today.
The only area that does not close completely is the Tethys Ocean but it is now an enclosed sea.
Slow expansion hypothesis
Hugh Owen refers to his work and ideas as slow expansion hypothesis. His work certainly has to be taken seriously even if you do not agree with any of it before, during or after investigating his ideas. What is more amazing is that the maps he has created were made without the help of computer software back in the 1980’s!
Owen was Head of the Department of Palaeontology of the British Museum and his Atlas of Continental Displacement book (link to book review or the free intro PDF version) was published by the Cambridge University Press.
In 1976, I presented a spherical geometric analysis of the bulk of the ocean-floor spreading evidence made available up to 1974. During this task, it was found that the continents would only fit together to form Pangaea, according to geological evidence, when the Earth’s diameter was 80% of its modern mean value. Below that figure, Pangaea could not be reformed without intracontinental dislocations.
Pangaea existed as a complete supercontinent until the middle Jurassic when it commenced to break up. The subsequent ocean-floor spreading patterns in the passive-margined oceans, in which the full history of continental splitting and subsequent displacement of continents apart is preserved, was found to support a near-linear increase in diameter up to the present day, consistent with the nearly straight limb of an exponential curve of increasing diameter.
Despite its firm base in field data, this ‘slow expansion hypothesis’ is widely discounted by many geologists and geophysicists at present, although perhaps fewer than in 1976.
H G Owen’s Preface to his Atlas of Continental Displacement book
Owen’s and others Expanding Earth theories are based on a smaller globe and the continents fitting together better or completely covering the surface.
What happened, how it happened, why it happened etc are normally very different for each Growing Earth theory.
Below are images showing Pangea in various reconstructions and breakups of this previous supercontinent.