Geological evolution of Etna volcano

Abstract

New stratigraphic and structural data obtained during recent geological surveys have allowed us to subdivide the almost continuous evolution of Etnean volcanism into four main phases. The oldest phase (Basal Tholeiitic) corresponds to a long period of dispersed fissuretype volcanism with tholeiitic affinity, from about 580 up to 260 ka. This phase represents the northward extension of the Plio-Pleistocene Hyblean volcanism to the Etnean region. The second phase (Timpe) started about 220 ka when eruptive activity was mainly concentrated on the Ionian coast along the NNW-SSE oriented Timpe fault system. In this area the occur rence of fissure-type eruptions formed a small shield volcano and the passage between tholeiitic to alkaline volcanics occurred. The third phase (Valle del Bove Centers) is marked by a main westward shift of the feeding system in the Valle del Bove (VdB) area forming some nested volcanic centers. The earliest volcanic edifices recognized are Tarderia and Rocche. Afterward the volcanism was mainly concentrated on the southwestern side of the VdB with the formation of Trifoglietto volcano. Local shifting of the feeder caused the for mation of three different volcanic centers: Giannicola, Salifizio and Cuvigghiuni. Finally, in the fourth phase (Stratovolcano) the definitive stabilization of the plumbing system led to the construction of the main stratovolcano, Ellittico, which forms the bulk of the present edifice. Four caldera-forming Plinian eruptions, occurring at about 15 ka, marked the end of Ellittico activity. During the Holocene, persistent basaltic volcanic activity formed the Mongibello volcano, whose products cover at least 85% of the Mount Etna area.

Climate forcing of volcano lateral collapse: evidence from Mount Etna, Sicily

“…While effusive activity from the youngest, major eruptive centres (Ellittico 80-15 ka and Mongibello 15 ka to present day; Branca et al 2004) has extensively remodelled and resurfaced the topography of much of the volcano, the outer flanks of the Valle del Bove preserve prominent, deeply incised valleys (figures 2 and 3) reminiscent of the parasol drainage pattern distinctive of volcanoes in tropical environments with high rainfall and surface runoff. The valleys are the downslope remnants (figure 3a) of a more vertically extensive channel system that originally drained elevated topography in that part of the volcano now occupied by the Valle del Bove, but which is now truncated by its enclosing cliff wall.…”

“…It has grown and developed over a period of 580 ka (Branca et al 2004) on the east coast of Sicily, upon a seaward-dipping substrate of sediments and basement rocks. Etna is a polygenetic volcano constructed from several centres of activity that show a broad age progression (oldest to youngest) from east to west (figure 1).…”

“…The earliest central-vent activity was concentrated in the vicinity of the Valle del Bove, leading to the formation of the Calanna centre, and later the Trifoglietto and associated centres further to the west. At around 80 ka BP (Gillot et al 1994;Branca et al 2004), activity switched to the northwest, (Tarquini et al 2007) showing the location of the Valle del Bove (VdB) relative to the current summit of the volcano. Also indicated are ancient centres of activity: Ellittico (E), Trifoglietto and associated centres (Tr) and Calanna (C).…”

UAV Thermal Infrared Remote Sensing of an Italian Mud Volcano

“…The geology of the area includes: 1) volcanic products erupted from Mt. Etna (Mongibello cycle, dated 35 ka to Present, [23] that outcrop in the northern and north-eastern parts of the area; 2) terraced alluvial deposits (mostly conglomerates and clays) dated to 125 to 40 ka [23]; 3) small outcrops of alkali lavas belonging to the Timpe phase [24] that are present in the central and north-western parts of the area, and are best represented by the volcanic neck of Paternò [25], whose age was calculated at 168 ka by [26] or at 210 ka by Condomines [27]; 4) sub-alkalic lavas dated to 580 to 250 ka [23]; 5) Early-Middle Pleistocene foredeep deposits (1200 -600 ka) mostly made of marly clays [23] that fill the Catania basin and outcrop in the eastern part of the area; 6) units of the Apenninic-Maghrebian collision belt, mostly composed of quartz-arenites and clays [28,23]. For the purposes of this study, the best site for the test was that of the Salinelle of Paternò Stadium, located at the NW boundary of the city of Paternò very close to the local football stadium.…”

Generation of Added Values Products Supporting Risk Analysis

“…Volcanism in the area has been continuing episodically for more than 230 million years, first in the Monti Iblei, in the southeast portion of Sicily, on the foreland of the African plate promontory, and, during the past half million years, in the Etnean area. The geological history of Etna is subdivided into four main periods (Branca et al, 2004). a. Basal Tholeiites…”