Now, Brown Bluff. Some gorgeous geology which unfortunately nearly all the expedition team were ignorant of. If they just learned some basics, they could add some really interesting info to the passengers. I mean, who doesn't like a volcano erupting underneath a glacier?? The geology lecturer on the cruise knows it of course, but not the zodiac drivers/exped staff.
So, a volcano started erupting underneath a thick glacier. Glacier melted from the bottom up, eventually breaking through to the surface. A crater formed in the ice, filled with water. Volcano continued to erupt under the water, forming glass and '
pillow lava' (have a read). After a while, either the lake fell a bit or the volcano rose above it, and then it rained down ash, tuff and volcanic bombs which deposited as sediments above the pillow lavas.
Here is the outcrop. Scree slope on the right; pillow lavas are black. Sub-aerial tuff and ash beds in brown. Uneven
Uneven surface between lavas and tuff/ash.
The round things are the 'pillows', cut through. The yellow between them is cough spalled off the lava as it hits the cold water. The ash layers begin above the lava.
You can see the volcanic bombs in certain layers of the ash beds above. I mean, just
phwoar!
OK, maybe that's enough of rocks ...
for now. I guess we haven't seen enough penguins
?
Penguin cam!!
Penguin highway (with a nice volcanic breccia in the R foreground)
Yes, ta-ta, Adélie penguins.
