Friday, February 15, 2008

Volcano Fieldwork Part 1

February 13-16th:
First few visits were to the Cerro Colorado region (Comarca highlands) and later Volcan Baru (to Boquete unfortunately during the same time as the jazz festival; no time to listen to music!).

We weren´t sure exactly which peak was Cerro Colorado, but we sure found the copper mine area easily. The view here is roughly south looking out from the terraced area where mining might continue in the future. We found some interesting deposits that we didn´t quite expect here; there were layers of pumice that must have come down from a volcano located higher up in the mountains. Where? Not sure yet, but for us, the pumice is far more interesting than measely copper veins!

After the quick visits in Chiriqui, we visited La Yeguada volcano in Veraguas. Before reaching the dome complexes, we stopped at a river crossing.

Here I am pointing at a kettle-like feature in the surface of a highly-jointed (entablatured jointing) ignimbrite.

We debated if this was a very glassy andesitic lava flow, but there are flow bands and compacted pumices (fiamme) within the unit. This is an interesting outcrop to study but also intreguing for the artistic eye.

The visit to La Yeguada provided a glimpse of what Karinne had been working with - heaping dacitic domes in an ill-defined crater with a poorly constrained age. This is a difficult field area...

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