I am broadly interested in the thermodynamic processes that lead to the generation of igneous and metamorphic rocks, particularly on those related with the evolution of magmas and their mineral phases, and how to quantify the evolution in terms of composition, pressure and temperature. I have developed and applied geothermobarometers (based on thermodynamic equilibrium of mineral phases) to determine the pressure and temperature evolution of ascending melts to understand magma recharge and mixing events, which are key processes in eruption triggering (e.g. Cortés et al in press; Cortés et al., 2006). As such, my research has contributed to the broader understanding of eruptive processes within a range of tectonic settings by providing information critical to deciphering the state and conditions of the magmas as they ascend through the crust (e.g. Cortés et al 2005; Cortés et al 2007). Recently, I have also incorporated kinetic aspects particularly the study of the crystal size distribution of mineral phases into my modelling (e.g. Cortés et al in press). The volcanic and tectonic environments within which I have worked include: high-potassium volcanic systems (Stromboli, Aeolian Islands); high alumina, calc-alkaline basaltic andesite persistently active systems in the Southern Andean Volcanic Zone (Villarrica and Llaima volcanoes); rhyolite volcanism associated with Caldera volcanism in the Central Andes (La Pacana Caldera, Northern Chile); and recently monogenetic volcanism in an intraplate setting (Lunar crater volcanic field, Nevada, USA). Although I employ principally theoretical and analytical approaches in my work, I also have a strong field-based background. Through my work for the Chilean Geological and Mining Survey Sernageomin, and subsequently during NSF-supported fieldwork in both, Chile and Nevada, I have gained experience mapping diverse volcanic terrains in remote environments (e.g. Cortés et al 2013; 2015; Valentine et al., 2017; and SERNAGEOMIN Maps: Cortés 2000; Cortés et al., 2007; De la Cruz and Cortés, 2012; Cortés 2012).
Some technical stuff here...

Publications (some for Downloading)

18. Valentine, G.A., Cortés, J.A., Rasoazanamparany, C., Widom, E., Smith, E.I., Johnsen, R., Briner, J., Harp, A.G., Turrin, B. 2017. Lunar Crater Volcanic Field (Reveille and Pancake Ranges, Basin and Range Province, Nevada, USA. Geosphere, 13(2), 1-48, doi: 10.1130/GES01428.1

17. Ruth, D.C.S., Cottrell, E., Cortés, J.A., Kelley, K.A., Calder, E.S. 2016. From Passive Degassing to Violent Strombolian Eruption: the Case of the 2008 Eruption of Llaima Volcano, Chile. Journal of Petrology, 57(9). 1833-1864. doi:10.1093/petrology/eqw063

16. Rasoazanamparany, C., Widom, E., Valentine, G.A., Smith, E.I., Cortés, J.A., Kuentz, D., Johnsen, R., 2015. Origin of Chemical and Isotopic Heterogeneity in a Mafic, Monogenetic Volcanic Field: A Case Study of the Lunar Crater Volcanic Field, Nevada. Chemical Geology, 397,76-93. doi:10.1016/j.chemgeo.2015.01.00

15. Cortés, J.A., Smith, E., Valentine, G.A., Johnsen, R., Rasoazanamparany, C., Widom, E., Sas, M., Ruth, D. 2013. Intrinsic conditions of magmas from the Lunar Crater Volcanic Field (Nevada). Implications for internal plumbing and magma ascent. American Mineralogist 100, 396-413. doi:10.2138/am-2015-4812 (Selected as Notable Paper for February-March 2015 by the chief-editor Keith Putirka).

14. Tadini, A., Bonali, F.L., Corazzato, C., Cortés, J.A., Tibaldi, A., Valentine, G.A., 2014. Spatial distribution and structural analysis of vents in the Lunar Crater Volcanic Field (Nevada, USA). Bulletin of Volcanology, 76,877. doi: 10.1007/s00445-014-0877-8

13. Johnson, P., Valentine, G.A., Cortés, J.A., Tadini, A. 2014. Basaltic tephra from monogenetic Marcath Volcano, Central Nevada. Journal of Volcanology and Geothermal Research, 281, 27-33. doi:10.1016/j.jvolgeores.2014.05.007

12. Pouget, S., Bursik, M., Cortés, J.A., Hayward, C.L. 2014. Use of principal component analysis for identification of Rockland and Trego Hot Springs tephras in the Hat Creek Graben, norheastern California, USA. Quaternary Research, 81, 125-137. doi:10.1016/j.yqres.2013.10.012

11. Valentine, G.A., Cortés, J.A., 2013. Time and space variations in magmatic and phreatomagmatic eruptive processes at Easy Chair (Lunar Crater Volcanic Field, Nevada, USA. Bulletin of Volcanology, 75, 752. doi:10.1007/s00445-013-0752-z

10. Cortés, J.A., Palma, J.L. 2013. Geological Applications of Self-Organizing Maps to Multidimensional Compositional Data. Pioneer Journal of Advances in Applied Mathematics. 7(2): 7:49.



9. Chiasera, B., Cortés, J.A., 2011. Predictive Regions for Geochemical Compositional Data of Volcanic Systems. Journal of Volcanology and Geothermal Research, 207(3-4):83-92, doi:10.1016/j.jvolgeores.2011.07.009



8. Cortés, J.A., 2009. On the Harker Variation Diagrams; a Comment on “The Statistical Analysis of Compositional Data. Where Are We and Where Should We Be Heading” by Aitchison and Egozcue (2005). Mathematical Geosciences, 41(7):817-828, doi: 10.1007/s11004–009– 9222–8



7. Self, S., De Silva, S., Cortés, J.A., 2008. Enigmatic Clastogenic Rhyolitic Volcanism: The Corral de Coquena Spatter Ring, North Chile, Journal of Volcanology and Geothermal Research, 177:812-821, doi:10.1016/j.jvolgeores.2008.01.047.

6. Cortés, J.A., Palma, J.L., Wilson, M., 2007. Deciphering Magma Mixing: the Application of Cluster Analysis to the Mineral Chemistry of Crystal Populations. Journal of Volcanology and Geothermal Research, 165:163-188, doi: 10.1016/j.jvolgeores.2007.05.018.




5. Cortés, J.A., Wilson, M., Condliffe, E., Francalanci, L. 2006. The Occurrence of Forsterite and Highly Oxidising Conditions in Basaltic Lavas from Stromboli Volcano. Italy. Journal of Petrology, 47(7):1345-1373, doi:10.1093/petrology/eg1012.



4. Calder, E., Cortés, J.A., Palma, J.L., Luckett, R., 2005. Probabilistic Analysis of Rockfall Frequencies during an Andesite Lava Dome Eruption: The Soufri`ere Hills Volcano, Montserrat. Geophysical Research Letters, 32:L16309, doi: 10.1029/2005GL023594.

3. Cortés, J.A., Wilson, M., Condliffe, E., Francalanci, L. 2005. The Evolution of the Magmatic System of Stromboli Volcano during the Vancori Period (26–13.8 ky). Journal of Volcanology and Geothermal Research, 147(1-2): 1–38.



2. Arriagada, C., Roperch, P., Mpodozis, C., Dupont-Nivet, Q., Cobbold, P., Chauvim, C., Cortés, J.A., 2003. Paleogene Clockwise Rotations in the Fore-Arc of Central Andes, Antofagasta Region, Northern Chile. Journal of Geophysical Research-Solid Earth. 108 (B1):2032 JAN 21 2003.

1. Aguirre, L., Cortés, J.A., Morata, D., Hervé, F., 1997. Low Grade Metamorphism of Mesozoic and Cenozoic Sequences of Patagonia (43◦–46◦), Chile. Revista Geológica de Chile. Vol. 24, N◦2, 187-201.