Solidified Flow
I do hope that some of you today take the time to explore some of this fascinating natural history of the rocks of Tasmania. I must admit the crash course I have taken to prepare these notes is still making my brain ache. Just when you think you have a handle of what is going on, Nature throws a "curve ball".
Preliminaries and then the bombshell. I've chosen this photo last because (as my title suggests) it fits the story at both a macro and micro level. In this rock itself we can see where molten lava has solidified. But the flow of this molten rock is very obvious. It is well worn now, because it is very old. On the broader scale, this rock was once part of a process that saw a complete realignment and reshaping of all the continents.
After all, continents are large rock bases that were sitting on a molten interior of the planet. Forces unimaginable allowed these large continents to break up and drift apart, being reshaped for at least 1.5 billion years. So the form our world map takes today is a temporary one - of course we are talking huge stretches of time. We can't even imagine what one million years is like. Try 4 billion years since the earth first began to be formed from the debris left over from the creation of our solar system. The earth is a dynamic system, always in flux. It's why it amuses me when people talk about a changing climate. Well, hello, the climate has always been changing and has changed far more dramatically in the past than it is now. Far more!
So here's the bombshell. Geologists in Tasmania have discovered that our island was once linked to the North American continent and only later came to be attached to mainland Australia. Tasmania moved with Antarctica (and Antarctica kept moving to the southern polar region - we know this because petrified forests have been discovered in Antarctica as it was once a balmy climate that was habitat for dinosaurs).
Here's a short TV discussion of these findings: www.youtube.com/watch?v=_f_Hcyfv5rU
So the geological origins of Tasmania are far more complex than we could ever imagine. No wonder I was confused trying to identify some of these rocks.
Here is a useful information sheet: dpipwe.tas.gov.au/Documents/FormationTas.pdf
www.themercury.com.au/lifestyle/university-of-tasmania-re...
Solidified Flow
I do hope that some of you today take the time to explore some of this fascinating natural history of the rocks of Tasmania. I must admit the crash course I have taken to prepare these notes is still making my brain ache. Just when you think you have a handle of what is going on, Nature throws a "curve ball".
Preliminaries and then the bombshell. I've chosen this photo last because (as my title suggests) it fits the story at both a macro and micro level. In this rock itself we can see where molten lava has solidified. But the flow of this molten rock is very obvious. It is well worn now, because it is very old. On the broader scale, this rock was once part of a process that saw a complete realignment and reshaping of all the continents.
After all, continents are large rock bases that were sitting on a molten interior of the planet. Forces unimaginable allowed these large continents to break up and drift apart, being reshaped for at least 1.5 billion years. So the form our world map takes today is a temporary one - of course we are talking huge stretches of time. We can't even imagine what one million years is like. Try 4 billion years since the earth first began to be formed from the debris left over from the creation of our solar system. The earth is a dynamic system, always in flux. It's why it amuses me when people talk about a changing climate. Well, hello, the climate has always been changing and has changed far more dramatically in the past than it is now. Far more!
So here's the bombshell. Geologists in Tasmania have discovered that our island was once linked to the North American continent and only later came to be attached to mainland Australia. Tasmania moved with Antarctica (and Antarctica kept moving to the southern polar region - we know this because petrified forests have been discovered in Antarctica as it was once a balmy climate that was habitat for dinosaurs).
Here's a short TV discussion of these findings: www.youtube.com/watch?v=_f_Hcyfv5rU
So the geological origins of Tasmania are far more complex than we could ever imagine. No wonder I was confused trying to identify some of these rocks.
Here is a useful information sheet: dpipwe.tas.gov.au/Documents/FormationTas.pdf
www.themercury.com.au/lifestyle/university-of-tasmania-re...