Mr. Collins will be speaking about reconstructing human origins.
During my first attempt to climb Mt. Hood 1964, I heard a cracking sound and watched a pickup load of rocks fall from Steel Cliff within 50 feet of our climbing team. This experience created an interest in Oregon’s volcanism, and I decided at that moment that I would visit all of the major volcanic areas in Oregon. Little did I know that this single event would lead me on a lifelong pursuit of knowledge about geology and a growing interest in the origins of the lava rocks that make up most of the Oregon landscape.
I also had another eye opening experience at Multnomah Falls (in the Columbia River Gorge) that added to my geological interests. I noticed standing on the bridge looking at the falls that the rock behind the falls was layered. There were layers of dark smooth rock (which I later discovered was low silica basalt) that were 20 to 50 feet thick, piled one on top of the other. They were layered in a way that, even to the non-scientific eye, showed they were at one time molten and I wondered if each layer had flowed into its position.
As I traveled on I-84 to the Tetons for many years, I also learned that there were other major eruptions in both North Central Oregon around the John Day Valley and in South East Oregon near the Nevada border.
One day I drove from Bend Oregon to John Day to look at both the Clarno volcanics north of the John Day Valley and the Picture Gorge basalt flows in the Southern end of the valley. I found that the area had evidence of many dikes (cracks in the crust) near Monument Oregon that led to huge basalt flows just like Eastern Oregon. I remember on the way back wondering if Picture Gorge was somehow related to other flows in Northeastern Oregon.
Eventually I ventured from Bend down through the Alvord Desert and over the Steens Mountains to French Glen. It was a very long day but it was an eye-opening trip for me. I saw layer upon layer of basalts which was evidence of a huge eruption in the past. Again.
In August, 2005, I decided to explore Southeastern Oregon, specifically to explore the Owyhee area and the McDermitt Caldera on the border of Oregon and Nevada. I found that there had been a huge explosion near the tiny town of McDermitt on the Oregon Nevada border which left a caldera 22miles wide by 28 miles long.
I finally sketched a map that showed the dates of all of the eruptions. This was an epiphany because I could see that all of these eruptions happened within 1 million years.
This presentation shows how all of these eruptions were connected or influenced by the same common source of magma. The primary cause was the hotspot that had risen under Oregon and is now the Yellowstone hotspot in Wyoming.