More details to follow about the Pu'u O'o flow, but going through my pictures, I discovered that I had a single shot that included the entire flow from start to finish: the copter was flying east of the flow, so Pu'u O'o is where the massive steam plume is rising on the right, while the Kalapana ocean entry is visible on the far left. The series of cliffs and rises are the palis, or fault scarps generated by slippage of the volcanoes towards the sea along major fault systems. Smaller steam plumes are vents and windows over the lava tube system, and the occasional surface flow. Note especially the pattern of forest islands, called kipuka. They are important biological refugia where some native species are protected from invasive predator species.