In geology, a supercontinent is when all or most of the
Earth’s continental blocks form a single landmass. But earth scientists may use
a different definition; ‘a clustering of nearly all continents’, which leaves
room for interpretation.
The land masses have conjoined and separated several
times. The most recent mass that joined them all is called Pangaea. This
conjoining began about 335 million years ago, and began to break up about 175
million years ago.
Pangaea looked more or less like a crescent or the letter
‘c’. The Eurasian continent sat at the top, with the area now forming southeast
asia stretching south and east. To the southwest lay North America, and along
the NA ‘east coast’ lay the west coast of the big hump of Africa, which was
pushed clockwise a bit off its southern tip. The bump of Brazil of South
America lay snuggled against North America and Africa. India and Antarctica
rested along the southeast of Africa, from the ‘Red Sea’ area south. Australia
nestled against India and Antarctica.
I used the words ‘lay’, ‘snuggled’ and ‘nestled’, but the
drawing I looked at indicated all sorts of irregular-shaped bits and pieces
scattered between all these known continents. I didn’t see anything that
resembled the Arabian Peninsula, so I can’t say where that particular piece was
hiding at the time of Pangaea.
Pangaea stretched from the south pole to within spitting
distance of the north pole. It was a solid body of land that would not have
allowed any ocean currents to go around the globe horizontally.
Pangaea began to break up about 175 million years ago.
Once India broke away from its neighbors, it raced toward Eurasia at 6 inches a
year. Is it any surprise that when they slammed together, they formed mountains
like the Himalayas? India (as well as Australia) is still moving northeast at
2-3 inches per year. In a few million years, Australia could scoop up bits and
pieces of Indonesia and then head for the northern Pacific. Will it?
I don’t know. Isn’t there a trench somewhere along
Indonesia? Seems like a deep ditch would slow Australia down or something.
Something else for me to look up and think about.
By the way, this is the first of probably several blogs
on super-continents. How long they take me and how often other subjects
insinuate themselves into the lineup of blogs remains to be seen. Thems the
chances you take when you decide to read my blog.
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