RT info:eu-repo/semantics/article
T1 Extremely high diversity of sulfate minerals in caves of the Irazú Volcano (Costa Rica) related to crater lake and fumarolic activity
A1 Ulloa, Andrés
A1 Gázquez, Fernando
A1 Sanz Arranz, Aurelio
A1 Medina García, Jesús
A1 Rull Pérez, Fernando
A1 Calaforra, José María
A1 Alvarado, Guillermo E.
A1 Martínez, María
A1 Avard, Geoffroy
A1 De Moor, J. Maarten
A1 Waele, Jo de
AB The caves of the Irazú volcano (Costa Rica), became accessible after the partial collapseof the NW sector of the Irazú volcano in 1994, offering the opportunity to investigateactive minerogenetic processes in volcanic cave environments. We performed a detailedmineralogical and geochemical study of speleothems in the caves Cueva los Minerales andCueva Los Mucolitos, both located in the northwest foothills of the main crater. Mineralogicalanalyses included X-ray diffraction (XRD) and Raman spectroscopy, while geochemicalcharacterization used Energy Dispersive X-ray spectroscopy (EDX) coupled to ScanningElectron Microscopy (SEM). In addition, measurements of environmental parameters in thecaves, cave drip water and compilation of geochemical analyses of the Irazú volcanic lake(~150 m above the cave level) and fumarole analyses were conducted between 1991 and2014. We identified forty-eight different mineral phases, mostly rare hydrated sulfates of thealunite, halotrichite, copiapite, kieserite and rozenite groups, thirteen of which are describedhere as cave minerals for the first time. This includes the first occurrence in cave environmentsof aplowite, bieberite, boyleite, dietrichite, ferricopiapite, ferrinatrite, lausenite, lishizhenite,magnesiocopiapite, marinellite, pentahydrite, szomolnokite, and wupatkiite. The presenceof other new cave minerals such as tolbachite, mercallite, rhomboclase, cyanochroite, andretgersite, is likely but could not be confirmed by various mineralogical techniques. Upliftingof sulfurous gases, water seepage from the Irazú volcanic lake and hydrothermal interactionswith the volcanic host rock are responsible for such extreme mineralogical diversity. Thesefindings make the caves of the Irazú volcano a world-type- reference locality for investigationson the formation and assemblage of sulfate minerals and the biogeochemical cycle of sulfur,with potential implications for Astrobiology and Planetary science.
SN ISSN 0392-6672
YR 2018
FD 2018
LK http://uvadoc.uva.es/handle/10324/35209
UL http://uvadoc.uva.es/handle/10324/35209
LA eng
NO International Journal of Speleology, Mayo 2018, vol. 47, n. 2. p. 229-246.
DS UVaDOC
RD 28-nov-2024