(1987) to classify the lake as meromictic, although in a second paper they changed its classification to oligomictic
(Gocke et al., 1990).
In both cases it is a highly angular unsorted oligomictic
chlorite phyllite breccia containing fractured and partly broken clasts and likely tectonic in origin (Fig 3b).
It usually includes a basal oligomictic
siliceous conglomerate (Table1), and its uppermost part contains marine intercalations of Spathian age (Belivanova, 2000).
After a quiescence period, caldera resurgence occurred during the Second Eruptive Epoch (SEE) with the formation of several vents inside it, most of them located at Olitas headstream; lava domes, block and ash flow deposits, pyroclastic surges and ignimbrites interbedded with lacustrine siltstones and torrential oligomictic
conglomerates remained restricted to the caldera depression, while ash fall tuffs mantled inflow and outflow zones (Figure 2)(Cepeda & Pardo-Villaveces 2004; Pardo-Villaveces et al., 2005).
These basement-derived, oligomictic
, and well-rounded or framework-supported conglomerate units have promise of being traced and/or correlated from section to section (Fig.
Rio Cuarto, appeared to be oligomictic
(tending toward meromictic).
In northwestern Napadogan area, the tuff is underlain by oligomictic
conglomerate whose quartzite clasts were derived from the Miramichi Group.