September 22, 2006, Newsletter Issue #172: Australian Geology
Tip of the Week
Geology Australia was once part of the enormous landmass Gondwanaland, which earlier formed part of the supercontinent Pangaea. Much of its geological history is remarkably ancient; the oldest known rock formations date from 3 billion to 4.3 billion years age.The great plateau of western Australia is underlain by a vast, stable shield of Precambrian metamorphic and igneous rocks, ranging in age from 570 million to 3 billion years old. These form the core of the ancestral continent, which, with Antarctica, had split off from Gondwanaland during the Jurassic Period, less than 200 million years ago, and had begun drifting eastward (see Plate Tectonics). Australia began to assume its modern configuration by the Eocene Epoch, some 50 million years ago, when Antarctica broke away and drifted southward.The thick sedimentary rocks of the Great Dividing Range were deposited in a great north-south trending geosyncline during an interval that spanned most of the Paleozoic Era (570 million to 225 million years ago). Compressive forces buckled these rocks at least twice during the era, forming mountain ranges and chains of volcanoes.
About LifeTips
Now one of the top on-line publishers in the world, LifeTips offers tips to millions of monthly visitors. Our mission mission is to make your life smarter, better, faster and wiser. Expert writers earn dough for what they know. And exclusive sponsors in each niche topic help us make-it-all happen.
| Guru Spotlight |
| Heidi Splete |
