Our plans changed as we realized that our trip to Payson would include 4 hours of driving. We opted to do it another time. Instead, we headed for Flagstaff where three National Monuments lie: Wupatki, Sunset Crater Volcano and Walnut Canyon. We made it to two of these.
The geology of Arizona has been puzzling me for a while now. When rockhounding with my friend Jamie in Wickenburg, south of here, we met a rock shop owner who mentioned that there had been volcanoes all around, hence contributing to the wonderfully colorful jaspers and agates all over AZ.
When we were in Oregon, I understood how the volcanic activity in Oregon created its colorful hard jaspers and agates, and its obsidian there, due to Oregon’s location on the Ring of Fire. The Ring of Fire refers to the volcanic area all around the Pacific (tectonic) Plate, which basically is underneath the entire Pacific Ocean, its edges at the US west coast and east coast of Eurasia (including Japan). Tectonic plates are constantly moving and floating, and when there is a large movement, an earthquake occurs such as the recent one that caused the tsunami that hit Japan. Plate tectonic action causes cracks in the Earth’s crust that allows molten lava to escape, thereby creating volcanoes.
What puzzled me was that Arizona is way too far inland to be part of the Ring of Fire. So, when visiting Arizona’s Sunset Crater Volcano National Monument yesterday, I had the opportunity to ask a knowledgeable Ranger. What I learned was that northern Arizona is actually on a small (comparatively) floating plate that moves in a back and forth rotation. For the past six million years, volcanic activity has created over 600 hills and mountains in the Flagstaff area, called the San Francisco Volcanic Field. In fact, Humphrey’s Peak, the highest point in Arizona, now currently snow-capped, was once a volcano. The Ranger told us that as we drive along I-40, every hill and mountain we see was either a volcano or created by lava flow.
Sunset Crater Volcano is the most recent, approximately 1000 years old, and spewed lava for 20 years, which is average for volcanoes. The layer of ash still can be seen all around, making it look like there was a recent forest fire. Gigantic fields of black lava, frozen in time can be seen along the drive through the park. The sunset name comes from the reddish colored cinder cone surrounding the crater at the top.
The process of breaking lava down into soil is transpiring now by fungus called lichen. The ash that was thrown into the air while the volcano was active brought rain and the ash that landed on the ground added nutrients to the soil. Ancient Puebloans settled here to farm this soil, with abundant rainfall, creating the village sites we now know as Wupatki and Walnut Canyon. By 1180 AD thousands farmed the area, by 1250, when the volcano had quieted, the Ancient Puebloans had moved on. Their descendants live today and the Hopi, the Zuni and the Navajo.
Walnut Canyon was a thrill to see. It is a huge mile deep grey/tan rocked canyon dotted with yucca, pines and cactus, with Walnut Creek running through the bottom. The inhabitants there farmed on the rimtop and made dwellings on the cliffs using clay blocks and covering them with a gold colored clay and used wooden beams, unique to these people. They came here because of the fertile soil created by Sunset Crater’s volcanic ash. There is a walking trail that takes about an hour and goes past some of the dwellings down to the bottom, and another walking trail that goes along the rim of the canyon. We walked along the rim and saw ancient dwellings along both sides of the canyon. Imagining how it once was, it must have been amazing to live there.
The meteor crater, where we are staying happened about 50,000 years ago, and Sunset Volcano erupted about 1000 years ago. Wish I had my camera to share, hopefully it will be back home soon…