Halema‘uma‘u lava lake beginning to perch

Over the past week, the lava lake in Halema‘uma‘u has developed a subtle levee around its perimeter that allows the lake to be slightly perched above its base, like a mesa. The levees grow from repeated small overflows, and the rafting and piling of pieces of surface crust that fuse together into a barrier that impounds the fluid lake. This is called a "perched" lava lake, and this geometry has been common for lava lakes at Kīlauea's summit and rift zones. For example, see this photo of a perched lava pond within Pu‘u ‘Ō‘ō crater in 2011. USGS photo by M. Patrick on Jan. 1, 2021.