Abstract The volcanic rocks of the Lower Cretaceous Parana-Etendeka Igneous Province, in Brazil, are grouped in the Serra Geral Group. The province can be chemically divided into low-TiO 2 ,… Click to show full abstract
Abstract The volcanic rocks of the Lower Cretaceous Parana-Etendeka Igneous Province, in Brazil, are grouped in the Serra Geral Group. The province can be chemically divided into low-TiO 2 , and high-TiO 2 . In southern Brazil, the low-TiO 2 lava pile reaches a thickness of ~ 1 km and is formed of heterogeneous lava packages here divided into four lava formations. Torres Formation (TF) is characterized by chemically more primitive basaltic (> 5 wt% MgO) compound pahoehoe flow fields; these lavas stratigraphically overly aeolian sandstones of Botucatu Formation and represent the onset of the volcanic activity. Vale do Sol Formation (VSF) groups vertically stacked sheet-like rubbly pahoehoe basaltic andesites (SiO 2 > 51 wt%; MgO 2 lava sequence. Sedimentary interbeds are preserved throughout the whole lava pile and were deposited during quiescence periods of volcanic activity, and represent important stratigraphic markers (e.g. TF-VSF contact). The newly proposed stratigraphy provides promptly recognized stratigraphic units in a regional framework of fundamental importance for future correlations and provide vital information in the understanding of how the Parana-Etendeka Igneous Province evolved through time.
               
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