A
Brief Study of Euramerica
Sometimes it’s called Euramerica,
sometimes it’s known as Laurussia (not to be confused with Laurasia). It’s
called a minor supercontinent because it consisted of several (3) cratons,
which are pieces of crust that include land.
About 410 million years ago, the
Laurentian (most of North America), the Baltica (Baltic states) and Avalonia
cratons all slammed together to form Euramerica. Avalonia was the smallest of
the 3; a microcontinent that was long and skinny and sat along the southern
border. Euramerica appears to have sat pretty squarely on the equator and was
mostly covered with tropical rainforests.
Around 300 million years ago, the
climate changed rather abruptly. Many of the lycopsids - such as clubmosses -
were replaced by ferns. There was a great loss of diversity in amphibians while
the reptiles diversified.
Later, Euramerica became part of the
major supercontinent Pangaea. When Pangaea broke into two continents - Gondwana
and Laurasia - Euramerica was a part of Laurasia.
Eventually, Laurasia split into the
continents of North America and Eurasia. The Laurentian craton became a big
portion of North America. Baltica became part of Eurasia. Avalonia ceased to be
a long skinny microcontinent as bits of it became some of the east coast of
North America, and bits became parts of Ireland, England and other areas of
southern Europe.
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