Tourmalinites from hydrothermal systems related to Permian rift magmatism of the Hercynian Saalian phase in Tuscany (Italy)

Water-Rock Interaction (WRI-6) 2026 Book chapter

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Authors: Giuseppe Cavarretta, Mariano Puxeddu, Marcello Franceschelli, Enrico Pandeli, Aldo Valori
DOI: 10.1201/9781003763505-35
Cited by: 2

Abstract

Tourmalinites are often present as pebbles within the basal metaconglomerate of the Middle Triassic Verrucano sequence of Tuscany. Two types were distinguished: 1) quartz-wacke (tourmalinized matrix up to 20-60%); 2) acidic volcanites in which tourmaline fills vugs, fractures and replaces pumices and phenocrysts. Type 1) has schorl: dravite ratio of 44:56 to 48:52 , uvite:dravite ratio of 9:91 to 27:73. Type 2 shows schorl:dravite ratio of 44:56 to 60:40 and uvite-dravite ratio of 12:88 to 37:63. Only alkali-defect substitution Na x +Mgy=Aly+□ x is widespread. Type 2 was produced by late magmatic fluids in volcanites. Type 1 origin.

Fields of Study & Subjects

Geological and Geochemical Analysis earthquake and tectonic studies Geological and Geophysical Studies Worldwide

Publication details

Journal / source
Water-Rock Interaction (WRI-6)
Publisher
CRC Press
Volume
1
Pages
141–144
Publication date
20 February 2026
Language
EN
Document type
Book chapter