In the extra-Andean sector of the Mendoza province, retro-arc volcanism was active from the Pliocene through to historic times. On the basis of its photogeological and geomorphological characteristics, the La Barda volcano is included in the Chapúa Group of Pliocene-lower Pleistocene aged volcanics.
La Barda is a pyroclastic monogenetic volcano composed mainly of interlayered lava spatter and cinder fall beds, a smaller proportion of pyroclastic surge beds and unwelded pyroclastic fall deposits with significant post-eruptive hydrothermal alteration. A 15 m thick clastogenic lava flow is interlaced in the sequence, indicating a Hawaiian-style lava-fountain eruption. The lava flow is affected by several sets of joints that intersect in some areas causing a columnar jointing-like structure.
Crustal xenoliths are described here, although ultramafic inclusions from the mantle have only been reported in two places nearby. The host basalt of these nodules has a massive, porphyritic texture with phenocryst assemblages of olivine-clinopyroxene and olivine-plagioclase.
The preserved volcano has a circular shape (500 m wide) with a depressed inner area in which there are radial dykes, agglomerates, and pyroclastic fall deposits. The lava flow dips radially toward the center by 23 to 65 degrees. The advanced erosion reveals the lava flows in 5 petal-like sections.
Here we describe and discuss the potential evolution of this "flower-shaped" volcanic erosion remnant

1. IAVCEI Commission on Monogenetic Volcanism