Petrology and geochemistry of the Frailes ignimbrite
The massive columnar-jointed flow of the main Frailes ignimbrite is dissected by the Pillkumayu river near Potosi, Bolivia
Main flow of the Frailes ignimbrite
Silicified elutriation columns resist erosion relative to the surrounding tuff of the main Frailes ignimbrite
Magmatic cordierite in a corundum-normative sample from the Condor Nasa ignimbrite flow.