Methane detection, Wieliczka Salt Mine. Mine engineer inserting a methane detector into cracks in a large salt crystal deposit at the Wieliczka Salt M

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Methane detection, Wieliczka Salt Mine. Mine engineer inserting a methane detector into cracks in a large salt crystal deposit at the Wieliczka Salt Mine. Methane gas can be lethal if allowed to build to dangerous levels underground. The salt mine at Wieliczka, Poland, is one of the oldest in the world. It was started in the 13th century and is still in use in the 21st century. By the 19th century, vast underground caverns had been excavated to depths of several hundred metres, including statues sculpted out of the salt deposits. In 1978, the mine became a UNESCO World Heritage Site.

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Size: 5197px × 3425px
Photo credit: © PATRICK LANDMANN/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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