Were the Annis Buttes and the Menan Buttes formed at the same time? Are they made of the same kind of lava rock as Craters of the Moon?

Question Answered by Charles Horsburgh retired Geologist Were the Annis Buttes formed at the same time as the Menan Buttes? They were, and are probably the oldest of what are generally known as the Menan Buttes. The Menan Buttes contains at least six volcanoes, including the Annis Buttes, the North and South Buttes, a non-descript…