PBS Nova - Sinkholes: Buried Alive (2015)
HDTV | 1280 x 720 | .MP4/AVC @ 3754 Kbps | 53 min 11 s | 1.46 GB
Audio: English AAC 161 Kbps, 2 channels | Subs: English
Genre: Documentary, Science
In a leafy suburb near Tampa, Florida, on February 28, 2013, a giant hole opened up under the bedroom floor of Jeffrey Bush, swallowing him as he slept. His body was never found. Bush was a victim of a sinkhole—a worldwide hazard that lurks wherever limestone and other water-soluble rocks underpin the soil. When carbon dioxide from the air dissolves in rainwater, it forms a weak acid that attacks soft rocks, riddling them with holes like Swiss cheese. Sinkholes can occur gradually when the surface subsides into bowl shaped depressions or suddenly when the ground gives way.