Because it is in a quarry, this set of profiles is very unique -- it
goes on for perhaps 50 meters and gets better and better as you walk.
The most immediately striking part is that a basalt flow covered a
soil, and baked the underlying soil to a bright red color. A new soil,
of perhaps 30-40cm thickness has formed on top of the basalt flow. At
the very bottom is another soil forming on top of a whitish rock layer
(tuff).
Underneath the basalt flow, we can still see many of the features of
the underlying soil. The most remarkable is the preserved structure of
the root cavities of the extinct palm which once dominated the
landscape here. In the photo that shows extra detail, you can see the
root traces as black lines. We think the black color is a manganese
mineral that forms around roots as they consume oxygen from the soil.
We sampled an area that has even more buried soils than you can see
here. We hope to be able to identify the plants that grew in each soil
and to find out if the plants changed over time.
Finally, remember you can look at larger versions of the photos by
clicking on them.
