Szczegóły publikacji
Opis bibliograficzny
Origin of andradite in the quaternary volcanic Andahua Group, Central Volcanic Zone, Peruvian Andes / Andrzej Gałaś, Jarosław MAJKA, Adam WŁODEK // Mineralogy and Petrology ; ISSN 0930-0708. — 2021 — vol. 115 iss. 3, s. 257–269. — Bibliogr. s. 268–269, Abstr. — Publikacja dostępna online od: 2021-03-13. — J. Majka – dod. afiliacja: Department of Earth Sciences, Uppsala University, Sweden
Autorzy (3)
- Gałaś Andrzej
- AGHMajka Jarosław
- AGHWłodek Adam
Słowa kluczowe
Dane bibliometryczne
| ID BaDAP | 134348 |
|---|---|
| Data dodania do BaDAP | 2021-05-27 |
| Tekst źródłowy | URL |
| DOI | 10.1007/s00710-021-00744-0 |
| Rok publikacji | 2021 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Creative Commons | |
| Czasopismo/seria | Mineralogy and Petrology |
Abstract
Euhedral andradite crystals were found in trachyandesitic (latitic) lavas of the volcanic Andahua Group (AG) in the Central Andes. The AG comprises around 150 volcanic centers, most of wich are monogenetic. The studied andradite is complexly zoned (enriched in Ca and Al in its core and mantle, and in Fe in this compositionally homogenous rim). The core-mantle regions contain inclusions of anhydrite, halite, S- and Cl-bearing silicate glass, quartz, anorthite, wollastonite magnetite and clinopyroxene. The chemical compositions of the garnet and its inclusions suggest their contact metamorphic to pyrometamorphic origin. The observed zoning pattern and changes in the type and abundance of inclusions are indicative of an abrupt change in temperature and subsequent devolatilization of sulfates and halides during the garnet growth. This process is interpreted to have taken place entirely within a captured xenolith of evaporite-bearing wall rock in the host trachyandesitic magma. The devolitilization of sediments, especially sulfur-bearing phases, may have resulted in occasional but voluminous emissions of gases and may be regarded as a potential hazard associated with the AG volcanism.