Using magma as a power source? Not as simple as it seems.

If you remember back a few years ago, I mentioned that my officemate, Dr. Naomi Marks, and her graduate advisors at UC Davis at the time, Dr. Peter Schiffman and Robert Zierenberg, along with other colleagues, drilled into an active magma chamber in Iceland. Now, rather than hitting basaltic lava like you might expect in Iceland, they hit a small pocket of rhyolite that was still molten (and wreaked havoc on their drill rig). The results of that serendipitous event were published in Geology showing that this rhyolite might be the product of melting of hydrothermally-altered basalts under Iceland (rather than being directly from a mantle source). Why would the basalts need to be hydrothermally altered? That comes down to needing to lower the melting point of basalt, so that new, mantle-derived basalts can impart their thermal energy of the old basalts and melt them - and hydrothermally altered the ...