Cracks in the Earth

Black Swan

Generally it was thought that the Earth's crust was elastic, and tended to rebound after earthquakes. Research in Atacama Chile now suggests that earthquakes of magnitude 7 or more may permanently fracture the Earth's crust. This permanent, non-elastic upper-plate deformation may be cause for the rethinking of how the Earth changes over geologic time.

I always knew the Earth was cracked (please excuse my metaphor).

Your thoughts?

gumbo1

Not really read the article! How could people think that millions of years of violent shaking wouldn't do damage to the crust?? I mean, yeah tectonic plates may slip and slide under/over each other but on the surface there would have to be severe damage being done!! All the layers between crust and molten rock absorb most of the damage but it will/has eventually do serious damage!! How was the grand canyon created? Was it 2 plates moving apart, silently without any shaking? I don't believe so!

im invisible

no, no... i dont believe so

Black Swan

gumbo1 wrote: »

How was the grand canyon created? Was it 2 plates moving apart, silently without any shaking? I don't believe so!

Current thinking regarding the formation of the Grand Canyon suggests that it was a relatively flat plain about 70 million years ago, later to experience tectonic uplift forming the Colorado Plateau, with multiple topographical ranges and valleys resulting from compressional deformation, folds, and plate rifts, followed by lake formation and extensive headwater erosion over millions of years; i.e., the beginnings of the Grand Canyon were essentially attributable to plate tectonics, followed by other changes over geologic time (e.g., erosion, etc.). Certainly such earth movements would have been accompanied by earthquakes of varying magnitudes, some of which may have been quite severe, but current geophysics models suggested a greater degree of elasticity than discovered recently in Chile cracks, hence such models may have to be revised.

gumbo1

Ok, but think bout this! We're all led to believe that the continents were close together something millions of years ago and that the spread out to where they are now, granted there still moving by mm every decade, do you think that it was a peaceful transgression??
I don't!! Volcanoes, earthquakes and natural erosion have all led to the current look of the earth. This can only lead to permanent cracks in the crust, if there wasn't so much tarmac and concrete around LA and parts of China we would see a lot more permanent cracks in the earth. The majority of major earthquakes recently have happened off-shore therefore not making the cracks visible.
Sorry if I've gone on a bit but this is something that I have kind of researched, not too much but a fair amount and drawn my own conclusions on.