Monday, January 29, 2018

Deadly debris flows in the SW U.S. fueled by drought, wildfire, and rain

On January 24, the LA Times reported that residents in the Montecito, California, area received conflicting information regarding evacuation zones prior to the worst post-fire floods and debris flows (often called mudflows) in recent California history. This is troubling news, as 21 people perished in these flows with two still missing, 65 homes were destroyed and another 462 were damaged.

To read the entire post, visit our Arizona Geology blog home - 

Image courtesy of ABC-15.

Friday, January 26, 2018

Got a geology story to tell

Got a geology story to tell? ESRI's StoryMaps might be just the platform you are looking for.
You'll find the entire blog text and pointers to a new USGS StoryMap on North America's mid-continental rift episode at

Wednesday, January 24, 2018

The Case for Navigable Rivers

Our newest post (22 Jan. 2018) presents Jon Fuller's 135-page contributed report on navigable rivers. This illustrated report includes case studies for three Arizona rivers: Gila, Salt and Verde Rivers.
Case for Navigable Rivers

Friday, January 05, 2018

Geology & uranium potential of Proterozoic rocks of the Central Arizona Arch and the Tonto Basin, Arizona

We are releasing a second suite of Phil Anderson’s geologic mapping and research of Proterozoic rocks, which includes geologic mapping and geochemical sampling of the Central Arizona Arch that covers roughly 3,000 square miles in central Arizona. 
Study area & example of sampling.

See our full blog post with links to the newly released maps at