See my post here:

Thread: Strange Sounds,Strange Rumblings, Sonic Booms, The Hum, Groaning, Earthquake Connection, Electromagnetic Voices, Post Your Recordings Here (Page 7)

This has a perfectly logical scientific explanation. Earth is shifting due to isostasy. Polar ice is melting causing the earth's crust to react in turn (continents subside, coastlines & small islands rise, sea floor shifts.

Permian period saw these changes too and we had a very hot, dry world. Gases began escaping and caused a massive extinction. We may be heading in that direction again. it's a perfectly natural, inevitable cycle. Special thanks to the industrial revolution for speeding up the process.