Re: The Flood
real life wrote:
So when , for instance, you find sedimentary rock AND coral atop Mt Everest......
And here's how it got there:
http://news.bbc.co.uk/1/hi/sci/tech/3047313.stm
Everest rock map published
By Carolyn Fry
More than 1,000 people climbed Mount Everest during the past 50 years but none thought to record the rock types beneath their feet. Now, after six years exploring the region, an earth scientist from Oxford University has created the first ever geological map of the mountain.
The 1:100,000-scale map, which covers around 1,500 square kilometres and straddles the Nepal-Tibet border, shows that rocks at the very top of the world's highest peak were laid down in a shallow tropical sea some 400 million years ago.
"I have some samples here in my office where you can still see tiny fragments of coral and conodonts which were once swimming around in an ocean somewhere near the equator," explains Dr Mike Searle, Research Fellow at Oxford's Department of Earth Sciences.
These marine sediments lie atop sedimentary and igneous rocks which have been baked by high temperatures and pressures into crystalline metamorphic rocks.
Many rocks around the base of Everest are unique granites containing unusual minerals such as tourmaline, garnet and mica.
Conveyor belt system
The strange juxtaposition is caused by the ongoing collision between two vast slabs of continental crust.
The Indian plate is moving northwards and piling into the Asian plate, in the process pushing rocks deep down into the crust. This subduction is in turn forcing the rocks above upwards - including those around Everest.
Two shallow faults slice through the mountain and over millions of years, subducted rocks have been transported above the higher fault and jacked up to form the higher Himalayan peaks.
"It's really a giant conveyor belt system," explains Dr Searle.
"Rocks are progressively subducted to the north, transferred above the fault and then progressively extruded to the south. The top of Everest is literally the uppermost layer of this extruding channel."
Dr Searle visited Everest five times from the Nepalese side and once from Tibet to gather information for the map.
As well as identifying rocks in the field, he gathered 400 samples for chemical analysis and examined aerial photographs and satellite images to map inaccessible areas.
----------
P