On September 19, 2021, as part of the 2021 Gila River Festival, I gave a field trip to interested citizen about the young (Quaternary) geology of the Upper Gila River Watershed. The field trip focused on stops along Highway 180 through the Mangas Valley and the Cliff/Gila Valley. We discussed the origins of the Gila Conglomerate, the volcanic history of the region, and the importance of the Gila River in shaping the landscapes we see today. Besides learning about the geologic history of the area, I took participants to Mule Creek to collect obsidian, and discussed the archeological importance of obsidian in tracking trade and understanding the lifestyle of indigenous peoples. On our last stop at the Iron Bridge, we discussed how river diversions impact sediment transport, flooding, and riparian ecology.
Below is a copy of the handout I prepared for the field trip.