What keeps the geoblogosphere awake at night?

The Accretionary Wedge #6 is up at the Lounge of The Lab Lemming. Chuck challenged us to write about “things which makes us go hmmm”, and the answers range from head-scratching over particular outcrops to musing on a planetary and even galactic-scale, with a couple of interesting sociological detours in between. There’s also the final word on the vexed topic of the Anthropocene: “ages are properly measured in numbers, not names”. Of course, the numbers sometimes change..!
It’s an interesting mix; I wonder if the differences in people’s answers reveal something about their attitudes to reseach? Top-down versus bottom-up approaches perhaps? Go and read, and see what you think.