Karl Karlstrom sitting on cross bedded outcrops of the Tapeats Sandstone that was deposited at sea level 500 million years ago and is now exposed deep in Grand Canyon.

(l. to r.): Researchers James Hagadorn (Denver Museum of Natural History, Karl Karlstrom and Laura Crossey (University of New Mexico) at Phantom Ranch

l. to r.) Researchers James Hagadorn (Denver Museum of Natural History, Karl Karlstrom and Laura Crossey (University of New Mexico) at Phantom Ranch

UNM Professor Karl Karlstrom looks at the basal sheet sands of the Tapeats Sandstone that pinch out to the left as they were draped across 500 million year old islands in the Cambrian sea.

James Hagadorn stands below Great Unconformity in Sixtmile Canyon. The discovery was that the tilted Sixtymile Formation beds below the flat lying Tapeats Sandstone are less than 508 million years old, not Precambrian as previously thought.

The Grand Canyon is one of the supreme geologic laboratories on Earth and, after about 140 years of geologic investigation, one might think that its secrets have been mostly resolved. This is especially true of the flat-lying layered rocks that are so...

Advocates say humanizing people on the streets helps address other concerns for the health and well-being of people who are experiencing instability in their housing. This week on New Mexico in Focus, correspondent Antonia Gonzales leads a conversation...