Beelzebub’s Tales About His Second Descent on to the Planet Earth—p185 notes

third great catastrophe

For long periods after this third catastrophe, this country Tikliamish was simply called ‘bare desert’ …

Maralpleicie … ‘Goblandia’ … “This locality also was afterwards covered by Kashmanoon and now the former principal part of this also once flourishing country is called simply ‘The Gobi Desert.’

Both Tikliamish and Maralpleicie were covered by ‘sands.’  The third group settled in ‘Pearl-land,’ which was not covered by ‘sands.’