Larry Richter, SBR resident, discussing the geologic history of Saguaro National Park
Linda Harvey
Colliding continents, volcanic eruptions of immense proportions, ocean, lakes, and dinosaurs are all part of the story of Saguaro National Park during the last 1.5 billion years. This was the opening to Larry Richter’s recent presentation to the SaddleBrooke Ranch (SBR) National Parks Club.
With the addition of animated videos, Larry provided a comprehensive history of the many phases and land changes that contributed to what is seen at and around Saguaro National Park (NP). The videos he shared were entertaining and made the evolution of a volcano come alive and be understandable.
Volcanoes played a major role in the formation of rocks in the park. Igneous rocks of granite and basalt are commonly found in the park. Granite forms from magma beneath the Earth’s surface, and basalt forms from lava on the Earth’s surface. Volcanic Tuff, a unique type of rock, is forme
d from the consolidation of volcanic ash.
Another important geological event that had a major effect on the park was the slow movement of large plates of the earth’s crust which seemingly crashed into each other but took millions of years to happen.
The park even has dinosaur footprints from at least 159 million years ago that have been revealed along Kinney Road. Later, about 100 million years ago a lake formed and a plant eating duck-billed dinosaur wandered into the area.
The National Parks Club thanks Larry Richter for an educational and entertaining meeting. His presentation was the last in our summer series of community sharing.
There will be a park presentation on Tuesday, Nov. 4, from 4 to 5:30 p.m. in La Mesa Room. For more information send an email to linda_harvey@hotmail.com.