Structure and Evolution
An exceedingly important and interesting volcano, El Condor is one of the few major central Andean volcanoes to be located wholly within Argentina (Figure 40.1). The volcano is remarkable for the large volume of apparently similar andesitic lavas it has erupted in recent times. A number of structural components are present:
1) An older volcanic edifice, of which remants are still preserved on the north-eastern flanks of the present volcano. This appears to have been deeply degraded prior to the most recent episode of activity, and no obvious volcanic features are preserved.
2) On the south part of the present volcano, an arcuate scarp of the older structure forms the eastern boundary to what appears to be a large caldera about 2.5 km in diameter, now completely filled with a group ( the "southern' group") of young andesitic or basaltic andesitic lavas (S). These have spilled out over the southern margin, and also flowed westwards, some of them travelling over 10 km. One flow (L1) extends 8 km eastwards from a discrete vent on the east flank of the caldera. It seems likely that many of the other flows originated in vents within the caldera.
3) The central part of the structure (C) includes the highest point of the volcano, and a small number of ash cones and small craters (Figure 40.2). The largest crater (SC) is pristine in shape; about 250 m in diamter, and located at the southernmost part of the summit complex. A number of lava flows appear to have originated from this complex, flowing mostly to the west and southwest. A few flowed northeastwards over older terrain; they include a distinctive 5 km long pale toned flow (L2) which appears different from the other, darker flows erupted from El Condor, and may be more silicic.
4) The northernmost part of the structure is a cluster of lavas arising from a source slightly north of and lower than the central cluster (N). A small pristine crater is present, and many well developed lavas with prominent levées extend westwards for 5-6 km. Passage of these flows appears to have been obstructed to the north and east and constrained westwards by a topographic scarp formed within the older volcanic construct, which may have been a caldera rim or an avalanche scarp. No flows emerged on the northern or eastern flanks.
5) Satellite vents of various ages.
Many of the flows on Cerro Condor appear pristine; it is not possible to distinguish any one as being more or less recent than another. The summit crater is exceptionally well preserved in view of its high altitude and exposure to frost shattering and thus is probably extremely young.
de Silva, S. L., and Francis, P. W., 1991. Volcanoes of the Central Andes. Berlin: Springer-Verlag, 216 p.