Another picture of a volcanic or lava bomb. This was from the same bomb field I wrote about the other day. The place is a geologist and volcanologist's dream, there are so many different types of rocks on the ground including a type of rock I can identify without looking it up - pumice. That's the bubbly type of rock you can see in a few places on the ground.
Like the bomb, pumice tends to be formed in violent volcanic eruptions. It's "frothy" molten lava that has a high gas and water content and when ejected in an eruption cools rapidly trapping the gases inside and forming "bubbles". The rock can be so light that it can actually float on water!
The ridge just to the east of Hale Pohaku is a bit of a mystery to me. Although I've known it was there for years I never bothered to walk up to it and have a look until now, but it has black sand, lava bombs, pumice and rocks that look as though they experienced some violence in the past. I'll try to find out if there's more known about it because it's certainly attracted my attention for now - speaking as a scientist of course!
One mystery is where the violent eruption took place. There's no obvious crater nearby but then again volcanic bombs and pumice can be hurled miles from the eruption site, so that brings a lot of possibilities into play. Just up slope, though, there's no obvious candidate.
Hey, me and my shadow! (to the bottom right).