Posted on 07/09/2013 2:11:45 PM PDT by null and void
Colored polygons represent different geological units that have been mapped (and inferred) by geologists over many years. These geological units formed before the continents broke apart, so we can use their position to put the "jigsaw pieces" back together again. Many other reconstructions do not use the geological boundaries to match the continental "jigsaw pieces" back together - so they don't align properly. Courtesy of University of Royal Holloway London
A new study published in the journal Gondwana Research, has revealed the past position of the Australian, Antarctic and Indian tectonic plates, demonstrating how they formed the supercontinent Gondwana 165 million years ago.
Researchers from Royal Holloway University, The Australian National University and Geoscience Australia, have helped clear up previous uncertainties on how the plates evolved and where they should be positioned when drawing up a picture of the past.
Dr Lloyd White from the Department of Earth Sciences at Royal Holloway University said: "The Earth's tectonic plates move around through time. As these movements occur over many millions of years, it has previously been difficult to produce accurate maps of where the continents were in the past.
"We used a computer program to move geological maps of Australia, India and Antarctica back through time and built a 'jigsaw puzzle' of the supercontinent Gondwana. During the process, we found that many existing studies had positioned the plates in the wrong place because the geological units did not align on each plate."
The researchers adopted an old technique used by people who discovered the theories of continental drift and plate tectonics, but which had largely been ignored by many modern scientists.
"It was a simple technique, matching the geological boundaries on each plate. The geological units formed before the continents broke apart, so we used their position to put this ancient jigsaw puzzle back together again," Dr White added.
"It is important that we know where the plates existed many millions of years ago, and how they broke apart, as the regions where plates break are often where we find major oil and gas deposits, such as those that are found along Australia's southern margin."
If you've ever watched documentaries like "One Million Years B.C." you would see that when the earthquakes occurred, the dinosaurs always fell into the resultant cracks. Science.
Anything is possible, once upon a time and all, strata belie strata.. no recorded history has clue what came before , or what will come.
It’s a good thing Columbus didn’t live back then. Such a long trip to discover where you’ve been.
Best dang movie documentary EVAH!
Neal Adams is a lot more entertaining than those “serious” scientists who believe one land mass broke up, with the pieces swimming around like sperms looking for an egg.
LOL, Of course!
Well, right after "Quest for Fire."
How could you forget the Discovery-level "you are there" drama:
I try to limit myself to hard science films.
>>I try to limit myself to hard science films.<<
Wait... what? Huh?
Ringo ISN’T a paleontologist?
While continental connections can be inferred by shape, what really solves the puzzle is geology. That is, if the shapes are roughly the same, do the mineral deposits where the two shapes meet, match?
For example, if there is a vein of quartz that dead ends on one side, is there a vein of quartz that dead ends on the other side? A two dimensional match of shape is one thing, but a three dimensional match is pretty conclusive.
The shallow seas in an area where there's a new continental rift are perfect places for the plankton that forms oil deposits to build up in sediments. The oil deposits aren't directly caused by the rifting process.
And there were supercontinents preceding Pangea, including Rodinia; before Rodinia things are a bit hazy and there's some debate over exactly what was going on.
..................Well, right after “Quest for Fire.”..............
Hho ah toho an hmm sisee eg who-tat-wah!
(Great flick!)
I meant to say “caused by the earth”,not “caused by the rift”. Your explanation is plausible.
There was a thread yesterday about some people trapped in a tree by some tigers - made me think of the scene with the saber-tooth cats. Sadly, I couldn't find a decent picture to post.
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