Portal de Periódicos da CAPES

Late Cretaceous high-potassium volcanism in eastern Srednogorie, Bulgaria

1978; Geological Society of America; Volume: 89; Issue: 3 Linguagem: Inglês

10.1130/0016-7606(1978)89 2.0.co;2

1943-2674

M. Boccaletti, P. Manetti, Angelο Peccerillo, G. Stanisheva-Vassileva,

Geology and Paleoclimatology Research

Research Article| March 01, 1978 Late Cretaceous high-potassium volcanism in eastern Srednogorie, Bulgaria M. BOCCALETTI; M. BOCCALETTI 1Istituto di Geologia e Paleontologia dell'Università, Via Lamarmora, 4 Firenze, Italy Search for other works by this author on: GSW Google Scholar P. MANETTI; P. MANETTI 2Istituto di Mineralogia, Petrografia e Geochimica dell'Università, Via Lamarmora, 4 Firenze, Italy Search for other works by this author on: GSW Google Scholar A. PECCERILLO; A. PECCERILLO 2Istituto di Mineralogia, Petrografia e Geochimica dell'Università, Via Lamarmora, 4 Firenze, Italy Search for other works by this author on: GSW Google Scholar G. STANISHEVA-VASSILEVA G. STANISHEVA-VASSILEVA 3Geological Institute of Bulgarian Academy of Sciences, Sofia, Bulgaria Search for other works by this author on: GSW Google Scholar GSA Bulletin (1978) 89 (3): 439–447. https://doi.org/10.1130/0016-7606(1978)89 2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation M. BOCCALETTI, P. MANETTI, A. PECCERILLO, G. STANISHEVA-VASSILEVA; Late Cretaceous high-potassium volcanism in eastern Srednogorie, Bulgaria. GSA Bulletin 1978;; 89 (3): 439–447. doi: https://doi.org/10.1130/0016-7606(1978)89 2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract The Srednogorie zone of Bulgaria was the site of extensive Late Cretaceous calc-alkalic and shoshonitic magmatism. The calc-alkalic volcanism developed mainly in the central and western parts, whereas shoshonitic volcanism was the predominant magmatic feature of the eastern part. Leucitic basanites, limburgites, and picrites occur in minor amounts in eastern Srednogorie. The shoshonitic volcanic rocks are intermediate to silicic in composition and are characterized by high K2O, K2O/Na2O around unity, high Rb, Sr, and Ba, and low TiO2 contents. They are associated with calc-alkalic rocks less strongly enriched in K and incompatible elements. Petrographically, the calc-alkalic rocks are characterized by the presence of hydrous mineral phenocrysts that are not present in the shoshonitic rocks. Shoshonitic and calc-alkalic rocks have some common chemical characteristics such as low TiO2, lack of absolute iron enrichment, and large overlap in many trace-element abundances. These are considered evidence for a genetic relationship between their primary magmas, which may have undergone different degrees of enrichment in incompatible elements.The eastward increase of K-rich volcanic rocks relative to calc-alkalic rocks in the Srednogorie zone is believed to be related to distension tectonics connected with the opening of the Black Sea. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.