| MadSci Network: Earth Sciences |
The Vishnu Schist and Zoroaster Granite are named after their type localities, Vishnu Temple and Zoroaster Temple in the Grand Canyon. When a geological formation or unit is named, the convention is to name it after the geographic location where it best observed or 'most typical'. That place is called the unit's 'type locale' or 'type section'. The reason for doing this is that anyone who wants to see a good example of any formation will know where to go to find it.
As for how Vishnu and Zoroaster Temples got their names, they were named by the explorer John Wesley Powell. Powell was a one-armed Civil War veteran who led the first successful expedition though the Grand Canyon in 1869. The story of this expedition is an epic adventure well worth reading. Disney even made a movie about it. The huge and majestic buttes in the Canyon reminded Powell of great ruined temples. He was familiar with Hindu writings, so he gave them names intended to inspire a sense of majesty, awe and mystery.
---- Sean Sherlock
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