“Alhambra Rock juts up northeast of Monument Pass, an errant monument with a very unusual origin. It is one of several diatremes in the region. It formed about 30 million years ago when a gas-driven vortex of material blasted upward from below Earth’s crust. It contains pieces of Earth’s mantle and of the rocks it punched through. Possibly moving faster than the speed of sound, the material probably followed old Precambrian faults. The rock is kimberlite, the type of...
Read MoreWoah – what happened there?!?!…At the speed of sound??
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