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'Crazy' formations near Lake Creek are lava flows

This may be a challenge for your geology skills. What are the crazy, wild rock formations in the Lake Creek area we saw on our jaunt up to a small waterfall by Camp Latgawa? They seem similar to Table Rocks and some smaller rock formations heading up Dead Indian Memorial Road. — Diana G.

We definitely lack geology skills, Diana. Luckily, we know the right people.

Charles Lane, a professor of geology at Southern Oregon University, says the formations are actually volcanic lava flows of the Heppsie Formation of the Cascades. It's on the north side of the South Fork Little Butte stream as you're traveling up toward Camp Latgawa.

When you're driving up the road, the lower slope of this formation is called the Wasson Formation. The Heppsie Formation is just above it.

"(They) form a buttress guarding the south approach to Heppsie Mountain," Lane tells us via email, adding the typical approach to Heppsie Mountain is off Highway 140.

The rocks are older than the Table Rocks, he goes on to say — "Miocene in age," or the geologic period that ran from 23 million to 5 million years before the present day.

"Although being somewhat different in composition from the Table Rocks, (it) nevertheless forms a resistant ridge that creates a dramatic landscape in combination with the gentle slope of the Wasson Formation below," Lane says.

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