The Tertiary dike magmatism in the Southern Alps: geochronological data and geodynamic significance

详细信息    查看全文

• 作者：Maria Aldina Bergomi ; Stefano Zanchetta…
• 关键词：Tertiary Periadriatic magmatism ; Southern Alps ; Dikes ; U–Pb zircon dating
• 刊名：International Journal of Earth Sciences
• 出版年：2015
• 出版时间：March 2015
• 年：2015
• 卷：104
• 期：2
• 页码：449-473
• 全文大小：8,149 KB
• 参考文献：1. Alagna KE, Peccerillo A, Martin S (2010) Tertiary to present evolution of Orogenic magmatism in Italy. J Virt Expl 36: paper 18. In: Beltrando M, Peccerillo A, Mattei M, Conticelli S, Doglioni C (eds) The geology of Italy: tectonics and life along plate margins, 2010
  2. Altherr R, Lugovic B, Meyer HP, Majer V (1995) Early Miocene post-collisional calcalkaline magmatism along the easternmost segment of the Periadriatic fault system (Slovenia and Croatia). Mineral Petrol 54:225-47
  3. Anderson DL (1994) The sublithospheric mantle as the source of continental flood basalts. Earth Planet Sci Lett 123:269-80
  4. Arculus RJ, Powell R (1986) Source component mixing in the regions of arc magma generation. J Geophys Res Solid Earth 91:5913-926
  5. Bargossi GM, Bove G, Cucato M, Gregnanin A, Morelli C, Moretti A, Poli S, Zanchetta S, Zanchi A (2010) Note illustrative della Carta Geologica d’Italia alla scala 1: 50.000—foglio 013 MERANO, ISPRA, pp 314
  6. Barth S, Oberli F, Meier M (1989) U–Th–Pb systematics of morphologically characterized zircon and allanite: a high-resolution study of the Alpine Rensen pluton (northen Italy). Earth Planet Sci Lett 95:235-54
  7. Bartoli O, Meli S, Sassi R, Magaraci D (2013) Amphiboles and clinopyroxenes from Euganean (NE Italy) cumulus enclaves: evidence of subduction-related melts below Adria microplate. Rend Lincei Sci Fis 24:151-61
  8. Beccaluva L, Gatto GD, Gregnanin A, Piccirillo EM, Scolari A (1979) Geochemistry and petrology of dyke magmatism in the Alto Adige (Eastern Alps) and its geodynamic implications. N Jahr Geol Palaontol 6:321-39
  9. Beccaluva L, Bigioggero B, Chiesa S, Colombo A, Fanti G, Gatto GO, Gregnanin A, Montrasio A, Piccirillo EM, Tunesi A (1983) Post collisional orogenic dyke magmatism in the Alps. Mem Soc Geol It 26:341-59
  10. Bell K, Castorina F, Lavecchia G, Rosatelli G, Stoppa F (2004) Is there a mantle plume below Italy? EOS Trans Am Geophys Union 85:541-47
  11. Beltrando M, Lister GS, Rosenbaum G, Richards S, Forster MA (2010) Recognizing episodic lithospheric thinning along a convergent plate margin: the example of the Early Oligocene Alps. Earth Sci Rev 103:81-8
  12. Benedicto A, Labaume P, Séguret M, Séranne M (1996) Low-angle crustal ramp and basin geometry in the Gulf of Lion passive margin: Oligocene–Aquitanian Vistrenque graben, southeast France. Tectonics 15:1192-212
  13. Berger A, Rosenberg C, Schmid SM (1996) Ascent, emplacement and exhumation of the Bergell Pluton within the Southern Steep Belt of the Central Alps. Schweiz Miner Petrogr Mitt 76:357-82
  14. Berger A, Burri T, Alt-Epping P, Engi M (2008) Tectonically controlled fluid flow and water-assisted melting in the middle crust: an example from the Central Alps. Lithos 102:598-15
  15. Berger A, Thomsen BT, Ovtcharova M, Kapferer N, Mercolli I (2012) Dating the emplacement and evolution of the orogenic magmatism in the internal Western Alps: 1. The Miagliano Pluton. Swiss J Geosci 105:49-5
  16. Bergomi MA (2004) Integrated study of “Gneiss Chiari-in the framework of the Orobic basement of Southern Alps (field relationships, mineral chemistry, geochemistry and geochronology). Eur J Min PLINIUS It Sup 30:54-9
  17. Bernoulli D, Jenkyns HC (2009) Ancient oceans and continental margins of the Alpine-Mediterranean Tethys: deciphering clues from Mesozoic pelagic sediments and ophiolites. Sedimentology 56:149-90
  18. Bigioggero B, Colombo A, Lanza R, Sacchi R (1981) Dati Geochimici e Paleomagnetici preliminari su filoni nel Sudalpino della zona del Biellese. Rend Soc Geol It 4:271-74
  19. Bigioggero B, Colombo A, Del Moro A, Gregnanin A, Macera P, Tunesi A (1994) The Oligocene Vallo del Cervo Pluton: an example of shoshonitic magmatism in the Western Italian Alps. Mem Sci Geol Padova 46:409-21
  20. Bill M, O’Dogherty L, Guex J, Baumgartner PO, Masson H (2001) Radiolarite ages in Alpine-Mediterranean ophiolites: constraints on the oceanic spreading and the Tethys–Atlantic connection. Geol Soc Am Bull 113:129-43
  21. Borsi S, Del Moro A, Sassi FP, Zirpoli G (1979) On the age of the Vedrette di Ries (Rieserferner) massif and its geodynamic significance. Geol Rund 68:41-0
  22. Boyet M, Lapierre H, Tardy M, Bosch D, Maury R (2001) Nature des sources des composants andesitiques des Gres du Champsaur et des Gres de Taveyannaz; implications dans l’evolution des Alpes occidentales au Paleogene. Bull Soc Géol Fr 172:487-01
  23. Brack P (1981) Structures in the southwestern border of the Adamello Intrusion (Alpi Bresciane, Italy). Schweiz Miner Petrogr 61:37-0
  24. Brack P (1984) Geologie der Intrusiva und Rahmengesteine des Sudwest-Adamello (Nord-talien). Mitt Geol Inst ETH Univ Zurich 7612, pp 253
  25. Brügel A, Dunkl I, Frisch W, Kuhlemann J, Balogh K (2000) The record of Periadriatic volcanism in the Eastern Alpine Molasse zone and its paleogeographic implications. Terra Nova 12:42
• 刊物类别：Earth and Environmental Science
• 刊物主题：Earth sciences
  Geology
  Geophysics and Geodesy
  
• 出版者：Springer Berlin / Heidelberg
• ISSN：1437-3262

文摘

The relationships between tectonics and magmatic activity in the Alps are still debated. Despite an active subduction since the Late Cretaceous, no arc-related magmatism is recorded prior of the Middle Eocene. The emplacement of plutons along the Insubric Fault in a short time span (~34-8?Ma) has been generally interpreted in terms of the slab break-off model. The Tertiary magmatism, however, is also characterized by the occurrence of widespread calcalkaline dikes not necessarily intruded along the Insubric Fault. The geochemical features of dikes vary along the Alps belt and are interpreted in terms of mantle source heterogeneity and degree of crustal contamination. U–Pb zircon dating of studied dikes indicates intrusion ages in the 42- to 34-Ma time interval. These data provide evidence for a pre-Oligocene magmatic activity that was not solely limited to the Adamello batholith. Moreover, it appears that dikes rejuvenate from SE to NW, in an opposite direction with respect to the Alpine subduction polarity. Thus, a more complex geodynamic scenario than the slab break-off model must be envisaged. The absence of arc magmatism prior to the Middle Eocene can be explained by the low-angle subduction of the Tethyan slab that confined the mantle partial melting zone away from the orogenic wedge. The onset of the Apennines subduction at 55-0?Ma caused the Alpine slab to retreat. The partial melting zone progressively migrated beneath the orogenic wedge and finally reached the axial belt in the Late Eocene, when the Alpine collision was completed. Only at this stage, slab break-off occurred and promoted the intrusion of the Periadriatic plutons.