Chapter 1 Introduction
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Downloaded from http://mem.lyellcollection.org/ by guest on September 26, 2021 Chapter 1 Introduction The Aeolian volcanic province is one of the main geological fea- merging volcanological, petrological and structural data into an tures in the Mediterranean area. It consists of seven main islands accurate temporal framework to facilitate a better understanding (Alicudi, Filicudi, Salina, Lipari, Vulcano, Panarea and Stromboli) of petrological, structural and volcanological problems; and forming a volcanic arc, and several seamounts (Eolo, Enarete, placing more cogent constraints on natural hazards from volcanism Sisifo, Lametini, Alcione and Palinuro). The Aeolian arc is a and related phenomena. most active volcanic structure, comprising a number of active Geological monographs and maps for the Aeolian archipelago (Stromboli and Vulcano) or dormant (Panarea and Lipari) volcanic were first presented by Cortese & Sabatini (1892) and Bergeat islands together with extinct volcanoes. (1899). In the first half of the 20th century these were followed Well known from prehistorical times, the Aeolian Islands by a wealth of contributions to particular problems of the stratigra- (Aeoliae Insulae from Aeolus, the Greek god of wind) have phy, petrology and volcanic activity and dynamics of the Aeolian attracted the interest and fantasy of ancient and modern naturalists, volcanoes. Detailed mapping at 1:10 000 started under the stimu- historians, travellers and artists. Tucidides, Aristotle, Pliny the lating leadership of Alfred Rittmann of the International Institute Elder, Strabo, Livy and Seneca gave early reports on volcanic of Volcanology (Catania) in the early to mid-1960s. H. Pichler, activity in the Ancient World, followed by many medieval to J. Keller, L. Villari, G.R. Romano and M. Rosi contributed signifi- modern scientists such as De´odat de Dolomieu, Lord Hamilton cantly to geological mapping and establishing first-order features and Giuseppe Mercalli. Papers by these authors represent mile- of the stratigraphy, petrology and volcanology of the Aeolian stones in the history of science, and the Aeolian archipelago can Islands. This work was compiled in the volume named ‘The be rightfully considered as the cradle of the scientific discipline Aeolian Islands: an active volcanic arc in the Mediterranean of Volcanology as shown by the definitions of the ‘strombolian’ Sea’ (Villari, 1980) and represented the last attempt to provide a and ‘vulcanian’ styles of eruptive activity. The Aeolian arc has coordinated, homogeneous geological framework for the whole attracted the attention of a great number of modern volcanologists, Aeolian Islands magmatic arc. Since the 1960s knowledge of tec- petrologists and structural geologists because of its complex suc- tonics (e.g. plate tectonics) and volcanology has increased steeply, cession of volcanic events, very variable structural setting and together with improved methods of chemical analysis that have wide range of magmatic compositions. All these characteristics allowed production of a great amount of major and trace element are closely related to each other, which stresses the need for inte- and isotopic data (both radiogenic and stable isotopes). Following grated multidisciplinary studies to understand the characteristics of the mapping of the 1960–70s, application of these advances facili- Aeolian volcanism. tated a wealth of petrological, volcanological and geophysical The Aeolian archipelago exhibits strong structural, volcanologi- studies by Italian and international research teams, greatly expand- cal and petrological variations. Active volcanoes are basically ing our knowledge of the structure of the Aeolian volcanoes, their restricted to the central (Vulcano and Lipari) and eastern (Strom- magmatic origins, evolutions and modes of eruption, and the geo- boli and Panarea) sectors of the Aeolian archipelago, where an dynamic setting of the arc. However, a complete set of geological extensional stress regime and a deep-focus earthquakes are maps of the whole Aeolian archipelago, compiled using modern detected as an effect of the north-westwards subduction of the criteria of stratigraphic nomenclature and considering the single Ionian lithospheric slab beneath the southern Tyrrhenian Sea. By islands in the framework of the activity of the entire archipelago, contrast, no historical eruptions are recorded in the western was still lacking. Publications providing a synthesis of data at a Aeolian archipelago (Alicudi, Filicudi and Salina) where only regional scale have been few. Only a few data have been available shallow seismicity is detected in a compressional tectonic on the submarine portions of the Aeolian volcanoes (except for regime. A first-order lithospheric fault system, the so-called Stromboli) until now. Tindari–Letojanni Fault, divides the western and eastern sectors Here we present new geological maps of the Aeolian Islands at a of the Aeolian arc. This structural divide is mirrored by along-arc scale of 1:10 000. These maps and related explanatory notes are variations of magma compositions becoming increasingly the focus of this Memoir and are the result of a decade of geologi- enriched in silica toward the central islands and more rich in pot- cal and structural fieldwork together with studies of aerial and sat- assium and radiogenic Sr from west to east. ellite images and numerous analytical data on the petrology and The Aeolian arc is therefore a key location where the relation- geochemistry (and even palaeomagnetic features) of the Aeolian ships between volcanism, geodynamics and magmatism can be rocks. Geological mapping has, to a considerable part, been pro- investigated. Problems that have been focused on during the last duced by the research team of the University of Bologna. It is pri- decades are many and include: (1) the nature and timing of volca- marily based upon the concept of unconformity-bounded units nic phenomena (such as eruptions, caldera and lateral collapses) (supersynthems, synthems, subsynthems) combined with informal and landslides; (2) the origin and evolution of magmas and their lithosomes and the classical lithostratigraphic units. This is a mul- relationships to geodynamics and volcanology; and (3) the tidisciplinary approach aimed at merging different features of a hazard from subaerial and submarine eruptions and collapses in volcanic setting such as the lithology and composition of volcanic the archipelago and surrounding areas. Implications for volcanic rocks, the geometry of rock bodies and their genetic features and hazard are primarily related to the currently active volcanoes of the unconformities which subdivide volcanic successions. Stromboli and Vulcano, but also include the hydrothermal field Special emphasis is placed on widespread marine deposits and of Panarea and the island of Lipari since recognition of its tephra layers that provide a general and synthetic framework of medieval-age Monte Pilato–Rocche Rosse eruption. Most, if not regional correlations into which the individual volcanic succes- all, of these problems can be better tackled if the stratigraphy sions are arranged. Accordingly, we provide a new perspective and mapping of each volcanic centre is known in detail. Such an on the geological history of the Aeolian Islands as the result of approach offers the possibility of: reconstructing the volcanic the interplay among volcanic activity of local and external pro- history of the single islands and of the entire archipelago; venance, volcano-tectonic processes, sea-level fluctuations and From:Lucchi, F., Peccerillo, A., Keller, J., Tranne,C.A.&Rossi, P. L. (eds) 2013. The Aeolian Islands Volcanoes. Geological Society, London, Memoirs, 37, 1–2. http://dx.doi.org/10.1144/M37.1 # The Geological Society of London 2013. Publishing disclaimer: www.geolsoc.org.uk/pub_ethics Downloaded from http://mem.lyellcollection.org/ by guest on September 26, 2021 2 INTRODUCTION regional fault systems, with a special look at the primary interlayered with and cutting through the volcanic successions. role played by volcano-tectonic and tectonic structures in control- Chapters 7 to 13 by Federico Lucchi, Francesca Forni, Gianfi- ling the localization of eruptive vents and eruptive processes lippo De Astis, Lorella Francalanci and co-workers deal with through time. Bathy-morphological maps of the submerged por- the stratigraphy, structural evolution, volcanology and petrology tions of the Aeolian Islands are also included in this Memoir, of the different islands of the Aeolian Archipelago. Each paper and provide important insights on the main volcanological and reports on the newly determined stratigraphy and mapping, and structural features that control the evolution of the Aeolian the history of eruptive activity and volcano-tectonic events of volcanoes. the Aeolian Islands. Information on rock compositions and the pro- The early maps and monographs could only use a limited cesses of magma origin and evolution is also provided for each number of radiometric age determinations from the mid-1960s, island, together with models of the volcanic plumbing systems which was the ‘dawn’ of radiometric dating. Now this Memoir and their evolution through time. These models are far from integrates, evaluates and discusses a considerable number of radio- being conclusive, but represent working hypotheses whose main metric age data (mostly 14C, K–Ar, Ar/Ar, fission track) and aim is that of stressing the importance of integrated structural, stra- archeomagnetic