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Parana-Etendeka Continental Basaltic Province represents one of the major volcanic events on Earth’s history. It's characterized by a fissural volcanism that occurred in the Early Cretaceous before the Gondwana rift and opening of South Atlantic Ocean. About 90% of the volcanism is found in South America, covering 1,200,000 km² over the Parana Basin (Parana Continental Basaltic Province). The other 10% are in Etendeka (Etendeka Continental Basaltic Province), and Angola, Africa ([[:file:Parana-Etendeka_1.jpg|Figure 1]]).

Parana-Etendeka Continental Basaltic Province represents one of the major volcanic events on Earth’s history. It's characterized by a fissural volcanism that occurred in the Early Cretaceous before the Gondwana rift and opening of South Atlantic Ocean. About 90% of the volcanism is found in South America, covering 1,200,000 km² over the Parana Basin (Parana Continental Basaltic Province). The other 10% are in Etendeka (Etendeka Continental Basaltic Province), and Angola, Africa ([[:file:Parana-Etendeka_1.jpg|Figure 1]]).

[[file:Parana-Etendeka_1.jpg|thumb|Figure 1. Location of the Parana-Etendeka CBP (modified from Jerram.<ref name=Jerram_2002>Jerram, D.A., 2002. Volcanology and Facies architecture of flood basalts. Geological Society of America, Special paper. In: Menzies, M.A., Klemperer, S.L., Ebinger, C.J., Baker, J. (Eds.), Magmatic Rifted Margins: Geological Society of America Special Paper, vol. 362, pp. 119e132.</ref>]]

[[file:Parana-Etendeka_1.jpg|thumb|300px|center|Figure 1. Location of the Parana-Etendeka CBP (modified from Jerram.<ref name=Jerram_2002>Jerram, D.A., 2002. Volcanology and Facies architecture of flood basalts. Geological Society of America, Special paper. In: Menzies, M.A., Klemperer, S.L., Ebinger, C.J., Baker, J. (Eds.), Magmatic Rifted Margins: Geological Society of America Special Paper, vol. 362, pp. 119e132.</ref>]]

The Parana Continental Basaltic Province covers an area of 917.000 km² and has a volume of 450,000 km³.<ref name=Frank_2009>Frank, H.T., Gomes, M.E.B., Formoso, M.L.L., 2009. Review of the areal extent and the volume of the Serra Geral Formation, Parana Basin, South America. Pesquisa em Geociências 36, 49e57.</ref> It is composed mostly (90% of volume) by basaltic and andesitic basalts rocks with a tholeiitic affinity. Acidic rocks occur locally in the upper volcanic pile. Chemically the basalts were divided in two groups based in the TiO2 contents: The first group occurs dominantly in southern areas and has TiO2 lower than 2 wt.%, the second group has high TiO2 (>2%) and is dominant in the northern portion of the Parana Basin.<ref name=Bellieni_1984>Bellieni, G., Comin-Chiaramonti, P., Marques, L.S., Melfi, A.J., Picirillo, E.M., Nardy, A.J.R., Roisenberg, A., 1984. High- and Low Ti flood basalts from the Paran_a plateau (Brazil): petrogenetic and geochemical aspects bearing on their mantle origin. Neues Jahrb. für Mineral. Abh. 150, 272e306.</ref><ref name=Mantovani_1985>Mantovani, M.S.M., Marques, L.S., De Sousa, M.A., Civetta, L., Atalla, L., Innocenti, F., 1985. Trace element and strontium isotope constraints on the origin and evolution of Paran_a continental flood basalts of Santa Catarina State, southern Brazil. J. Petrol. 26, 187e209.</ref> These two groups of basaltic rocks were sub-divided in six magma types<ref name=Peate_1992>Peate, D.W., Hawkeswort, C.J., Mantovani, M.S.M., 1992. Chemical stratigraphy of the Paran_a lavas (South America): classification of magma types and their spatial distribution. Bull. Volcanol. 55, 119e139.</ref>:  Gramado, Esmeralda and Urubici (Ti/Y<300) in the south, and Pitanga, Paranapanema and Ribeira (Ti/Y>300) in the northern magmas.  

The Parana Continental Basaltic Province covers an area of 917.000 km² and has a volume of 450,000 km³.<ref name=Frank_2009>Frank, H.T., Gomes, M.E.B., Formoso, M.L.L., 2009. Review of the areal extent and the volume of the Serra Geral Formation, Parana Basin, South America. Pesquisa em Geociências 36, 49e57.</ref> It is composed mostly (90% of volume) by basaltic and andesitic basalts rocks with a tholeiitic affinity. Acidic rocks occur locally in the upper volcanic pile. Chemically the basalts were divided in two groups based in the TiO2 contents: The first group occurs dominantly in southern areas and has TiO2 lower than 2 wt.%, the second group has high TiO2 (>2%) and is dominant in the northern portion of the Parana Basin.<ref name=Bellieni_1984>Bellieni, G., Comin-Chiaramonti, P., Marques, L.S., Melfi, A.J., Picirillo, E.M., Nardy, A.J.R., Roisenberg, A., 1984. High- and Low Ti flood basalts from the Paran_a plateau (Brazil): petrogenetic and geochemical aspects bearing on their mantle origin. Neues Jahrb. für Mineral. Abh. 150, 272e306.</ref><ref name=Mantovani_1985>Mantovani, M.S.M., Marques, L.S., De Sousa, M.A., Civetta, L., Atalla, L., Innocenti, F., 1985. Trace element and strontium isotope constraints on the origin and evolution of Paran_a continental flood basalts of Santa Catarina State, southern Brazil. J. Petrol. 26, 187e209.</ref> These two groups of basaltic rocks were sub-divided in six magma types<ref name=Peate_1992>Peate, D.W., Hawkeswort, C.J., Mantovani, M.S.M., 1992. Chemical stratigraphy of the Paran_a lavas (South America): classification of magma types and their spatial distribution. Bull. Volcanol. 55, 119e139.</ref>:  Gramado, Esmeralda and Urubici (Ti/Y<300) in the south, and Pitanga, Paranapanema and Ribeira (Ti/Y>300) in the northern magmas.  

Acidic rocks are characterized by high crystallization temperatures. In the Paraná Basin, temperatures obtained by the coexisting pyroxenes method are 1,030 ± 38ºC:<ref name=Bellieni_1984 />. Chemically the acidic rocks are also divided in two groups<ref name=Bellieni_1984 /><ref name=Peate_1997>Peate, D.W., 1997. The Parana-Etendeka province. In: Mahoney, J.J., Coffin, M. (Eds.), Large Igneous Provinces: Continental, Oceanic, and Planetary Volcanism: Geophysical Monograph Series, vol. 100. American Geophysical Union, pp. 217e245.</ref>

Acidic rocks are characterized by high crystallization temperatures. In the Paraná Basin, temperatures obtained by the coexisting pyroxenes method are 1,030 ± 38ºC:<ref name=Bellieni_1984 />. Chemically the acidic rocks are also divided in two groups<ref name=Bellieni_1984 /><ref name=Peate_1997>Peate, D.W., 1997. The Parana-Etendeka province. In: Mahoney, J.J., Coffin, M. (Eds.), Large Igneous Provinces: Continental, Oceanic, and Planetary Volcanism: Geophysical Monograph Series, vol. 100. American Geophysical Union, pp. 217e245.</ref>

# Palmas type, dacitic and rhyolitic rocks with low TiO2 and low contents of incompatible elements, dominant in the south of Parana Basin and is sub-divided in 5 sub-groups based on chemical characteristics:<ref name=Peate_1992 /><ref name=Nardy_2008>Nardy A.J.R., Machado F.B., Oliveira M.A.F. 2008. As rochas vulcânicas mesozoicas ácidas da Bacia do Paraná: litoestratigrafia e considerações geoquímicas-estratigráficas. Revista Brasileira de Geociências, 38(1):178-195.</ref> Caxias do Sul, Santa Maria, Anita Garibaldi, Clevelandia and Jacui.  

# Palmas type, dacitic and rhyolitic rocks with low TiO2 and low contents of incompatible elements, dominant in the south of Parana Basin and is sub-divided in 5 sub-groups based on chemical characteristics:<ref name=Peate_1992 /><ref name=Nardy_2008>Nardy A.J.R., Machado F.B., Oliveira M.A.F. 2008. As rochas vulcânicas mesozoicas ácidas da Bacia do Paraná: litoestratigrafia e considerações geoquímicas-estratigráficas. Revista Brasileira de Geociências, 38(1):178-195.</ref> Caxias do Sul, Santa Maria, Anita Garibaldi, Clevelandia and Jacui.  

# Chapeco Type, porphyritic trachytes with high-TiO2, Ba, P, Zr and Sr. Present in the north and middle portions of the basin and is sub-divided in 3 sub-groups: Ourinhos, Guarapuava<ref name=Peate_1997 /> and Tamanara.<ref name=Nardy_2008 />

# Chapeco Type, porphyritic trachytes with high-TiO2, Ba, P, Zr and Sr. Present in the north and middle portions of the basin and is sub-divided in 3 sub-groups: Ourinhos, Guarapuava<ref name=Peate_1997 /> and Tamanara.<ref name=Nardy_2008 />

The age of magmatism in the Serra Geral Formation is Early Cretaceous. The volcanic rocks are slightly older in the south portion ranging from 131,4 ± 1,6 to 132,9 Ma, becoming younger in middle (129,9 ± 0,1 Ma ) and north (131,9 ± 0,9 Ma ).<ref name=Renne_1992>Renne, P. R., Ernesto, M., Pacca, I.G., Coe, R.S., Glen, J.M., Prevot, M. & Perrin M. 1992. The age of the Paraná Flood Volcanism, rifting of Gondwanaland, and the Jurassic-Cretaceous boundary. Science, 258: 975- 979</ref> The duration of the main phase of the volcanism was <1.2 My<ref name=Renne_1992>Renne, P.R., Glen, J.M., Milner, S.C., Duncan, A.R., 1996. Age of Etendeka flood volcanism and associated intrusions in southwestern Africa. Geology 24, 659e662.</ref> (Continental Basaltic Provinces are known to display a variety of lava flow morphologies).  

The age of magmatism in the Serra Geral Formation is Early Cretaceous. The volcanic rocks are slightly older in the south portion ranging from 131,4 ± 1,6 to 132,9 Ma, becoming younger in middle (129,9 ± 0,1 Ma ) and north (131,9 ± 0,9 Ma ).<ref name=Renne_1992>Renne, P. R., Ernesto, M., Pacca, I.G., Coe, R.S., Glen, J.M., Prevot, M. & Perrin M. 1992. The age of the Paraná Flood Volcanism, rifting of Gondwanaland, and the Jurassic-Cretaceous boundary. Science, 258: 975- 979</ref> The duration of the main phase of the volcanism was <1.2 My<ref name=Renne_1992>Renne, P.R., Glen, J.M., Milner, S.C., Duncan, A.R., 1996. Age of Etendeka flood volcanism and associated intrusions in southwestern Africa. Geology 24, 659e662.</ref> (Continental Basaltic Provinces are known to display a variety of lava flow morphologies).