June 4, 2010
A Plumbing Problem
image by Henrik Bondo
This is a leaky area of the Moon with little ponds of lava filling crater bottoms and other low spaces. Some of the lavas are within the outer, nearly invisible rims of the Humorum Basin and rose up basin-made fractures. And Crüger - near top left - probably contains mare material because it marks a totally covered basin. But the reasons are uncertain for the existence of other small ponds near Billy (top center) and the unnamed deposit above bottom left. Magma formed in the lunar mantle, typically 45 km or so below the crust today, and to reach the surface there must have been crustal cracks that allowed it to rise buoyantly. The only known way to made deep fractures is crater and basin formation, but I don't see ones large enough at those leaky sites. While thinking about that enjoy the browns of different lavas and the wispy blue hues of fresh crater rays and powders.
28 Jan 2010. Here is Henrik's entire lovely mosaic of the western limb.
Rükl plate 51 and neighbors