2016 President's Field Trip: Lava Flows and Accreted Terranes
Landslide that happened last November at Arcadia Beach on the northern Oregon Coast.
Field trip leader, GSOC President Bo Nonn, posing next to some pillow basalts at Arcadia Beach.
An abandoned section of very bad pavement (due to continuing landslide) on Hwy 101 north of Newport.
Elephant Rock at Seal Rock State Park just north of Waldport, Oregon. This represents Columbia River Basalt overlying older Yaquina Formation sediments.
GSOC group watches the rising waves at Cape Perpetua, then decides to go back to the cars as a large wave washes over the platform of basalt.
Our last stop on Day one is at the Darlingtonia Wayside, where we enjoyed seeing these carnivorous pitcher plants. Time to go get our dinners too.
On Sunset Bay, SW of Coos Bay, we viewed cliffs made up of Coaledo Formation. The layers are tilted sharply upward in the cliffs, & overlain w/Whiskey Run terrace of sandstone, 80' above sea level.
In the foreground is the root system of a tree inundated the tsunami generated by Oregon's last subduction quake around 1700.
At Shore Acres, just to the south, we hiked up to the top of the terrace, where sandstone was sculpted into beautiful formations.
Later, on the beach south of the Bandon jetty, we were examining rock outcrops and picking up nice pebbles, when we noticed someone had left this lovely sculpture.
Our last stop of the day was at Cape Blanco, where we hiked down to the beach to look at more cool rocks. In the blue shirt, second from right, is our leader for the day, Frank Hladky.
Our leader on Day 3 was Roger Brandt. He interpreted streamside boulders and cobbles for us. Here are layers of "sheeted dikes" from deep ocean crust. They form vertically, but have been tilted 90°.
Our first stop on Day Three was the middle fork of the Smith River in Northern California
Up into the steep hills to find a beautiful outcrop of green serpentenite. Past President Sheila Alfsen helped to organize and lead parts of this trip.
It was a close call but we managed to escape Oregon's only carnivorous plant, Darlingtonia.
Most of the group, after touring the Oregon Caves. Sheila stayed at the lodge to give us a program afterwards.
Inside the cave, we photographed these signatures, beginning "Prof Thom. Condon," and listing his students. The signatures are about 125 years old, encased in a thin layer of calcite.
It was really fun to explore the caves with our group.
Some of the group left after the cave tour to return to Portland. A hardy bunch continued south to Mount Ashland, where we had this view south of Mount Shasta.
An inclusion of pegmatite in the local granite outcrop.
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