In September 1990, a group of scientists put a drill head to the ground in southern Germany, where two landmasses once merged to form the supercontinent Pangaea 300 million years ago. Their goal? To drill the deepest hole ever made into the earth, a "telescope" into its core.The main borehole reached a depth of 9101 meters into the en.wikipedia.org/wiki/Continental_crust . The deep-drilling experiment yielded huge surprises about the structure of the earth, including maps of rock temperature, new information about seismic pressure, and beautiful models that show layers of rock wrapped around each other like ribbons,-illustrating how the crust is far from a neat layer cake.accessible hole in the world. But what did these insane engineering projects reveal outside of the realm of the scientific. How did it smell, for example, and what did it sound like down there?Dutch artist www.geeven.nl/answered the latter question this year through an extended collaboration with geoscientists from the www.gfz-potsdam.de/startseite/ , which controls the KTB borehole now that drilling has stopped.With the help of the scientists (and an acoustic engineer from www.arup.com/ ), Geeven set out to discover what the borehole sounds like at its furthest depths. With the help of the scientists (and an acoustic engineer from www.arup.com/ ), Geeven set out to discover what the borehole sounds like at its furthest depths. The recording she brought back—accompanied by photos of the crew and a seismic reading—is an intense, almost warm audio landscape of echoes and crunches. It's the closest we can get to hearing the sounds of the earth's core.*Kola Superdeep Borehole @ 29,858 feet is not accessible*