The core can be inferred from density measurements and the refraction of P & S waves, I did an OU course about 30 years ago that took me into that in some detail but it was still just skimming the surface of the subject I think. I believe there is a lot of agreement that the reason the core is still as hot as it is today is the result of a natural nuclear fission reactor in the core, a lot of those radionuclides did sink down there early on
Do you mean induced P and S waves or thoses from seismic events? The hydrocarbon industry has long used seismic as a way of mapping the subsurface, however a hole in the ground tends to provide clarity to the seismic picture. Seismic alone is not quite enough, but a good starting point. Its a shame we cannot (yet) drill down into the core and take a glimpse.
Seismic events, and I guess some of the results from nuclear tests. I don't think we will ever have a materials technology that would withstand the pressure and temperature involved some places we just can't physically explore.
I read somewhere, that sometime in the future, that scientist may tap into the earths core for energy. A bit like geothermal, but on a massive scale. Scary.
Our planet is a huge source of energy. In fact 99.9% of the planet is at a temperature greater than 100 degrees Centigrade. Geothermal Engineering intends to tap into this heat and, in so doing, aims to produce significant quantities of renewable electricity and heat. However: http://www.chroniclelive.co.uk/news/north-east-news/giant-2km-borehole-project-fails-8189518 But: http://www.geoexpro.com/articles/2010/06/mining-heat
There are wells in the North Sea where the bottomhole temperature at 20000 feet (3.87 miles) is 200 degrees Centigrade. And although they are drillable, it becomes more problematic at those temperatures. But only a mere 4 miles into the crust. And in Cornwall, again, we are looking at 200 degrees C, 3 miles down. http://www.cleantechinvestor.com/portal/geothermal/9068-hot-dry-rocks.html
That's been around in sci-fi for quite a while, a much more interesting and scary idea is what does a civilisation do when it runs out of living space, answer :- dismantle the solar system apart from the star and build a dyson sphere (if you are really clever) or on a smaller scale a ring world of a radius that puts you in the goldilocks zone, they reckon there is enough stuff in a solar system to build one The real-estate that would be available on a ringworld would be stupendous, a ringworld is a ring of one astronomical unit radius around the sun a ring 184 million miles in diameter
Scale again, I guess the energy gradient at that depth is sufficient to maintain the output, i.e. new energy (heat) from the surroundings and deeper down comes along quick enough to replace what we extract, if so then great I'm all for it!
When I was in Sweden we were in ambient temperatures of -35 centigrade, however the liquid returns back from the wellbore 3 or 4 miles down kept the rig crew warm. These guys had previously drilled some of the pilot geothermal wells in Cambourne.
Cant really say much on here but we might well be involved in a geothermal prospect closer to your own back yard, Oss.
