Found: Prehistoric Indian Ocean mini-continent
FRANCE: Scientists said Sunday they had found traces of a
micro-continent hidden underneath the Indian Ocean island of Mauritius.
The slab, dubbed Mauritia, was probably formed around 61-83 million
years ago after Madagascar split from India, but eventually broke up and
became smothered by thick lava deposits, they said. In a study published
in the journal Nature Geoscience, scientists analysed beach sand on
Mauritius that contained ancient zircons between 660 million and about
two billion years old.
The minute chips of mineral were a remarkable find, as they were
buried in sand formed only recently in geological terms -- from
nine-million-year-old volcanic rock.
“The zircon points to the existence of fragments of an ancient
micro-continent beneath the island (Mauritius), pieces of which were
brought to the surface by recent volcanic activity,” said a Nature
statement.
The Indian Ocean floor may be littered with hidden land fragments
that broke off as the once super-continent Pangea split up and formed
the continents we know today, the paper suggests.
Pangea began to rift about 200 million years ago, yielding Gondwana
in the south and Laurasia in the north.
Gondwana in turn split into Madagascar, Australia, Antarctica and
India between 80 and 130 million years ago.
The new study suggests that Mauritia became detached when Madagascar
and India split up. The Seychelles, it adds, could be like Mauritia --
another continental fragment that, however, is visible.
AFP
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