Contrasting triggering mechanisms of the 2001 and 2002–2003 eruptions of Mount Etna (Italy)

Neri, Marco; Acocella, Valerio; Behncke, B.; Maiolino, Vincenza; Ursino, Andrea; Velardita, Rosanna

doi:10.1016/j.jvolgeores.2004.11.025

Cited by 109 publications

(108 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(4) Eruptionrelated seismicity, such as tremor amplitude and explosion quakes showed a marked drop about 30 min before the 1425 GMT event (S. Falsaperla, personal communication 2007). All these facts contrast markedly with what is known from multiple observations of flank eruptive fissures opening on Etna (Calvari et al 1994b;Bertagnini et al 1990;Calvari and INGV staff 2001;Acocella and Neri 2003;Neri et al 2004Neri et al , 2005Andronico et al 2005).…”

Section: Major Pyroclastic Density Currents Generated By Hydromagmatimentioning

confidence: 57%

Pyroclastic density currents resulting from the interaction of basaltic magma with hydrothermally altered rock: an example from the 2006 summit eruptions of Mount Etna, Italy

et al. 2008

View full text Add to dashboard Cite

After 16 months of quiescence, Mount Etna began to erupt again in mid-July 2006. The activity was concentrated at and around the Southeast Crater (SEC), one of the four craters on the summit of Etna, and eruptive activity continued intermittently for 5 months. During this period, numerous vents displayed a wide range of eruptive styles at different times. Virtually all explosive activities took place at vents at the summit of the SEC and on its flanks. Eruptive episodes, which lasted from 1 day to 2 weeks, became shorter and more violent with time. Volcanic activity at these vents was often accompanied by dramatic mass-wasting processes such as collapse of parts of the cone, highly unusual flowage processes involving both old rocks and fresh magmatic material, and magmawater interaction. The most dramatic events took place on 16 November, when numerous rockfalls and pyroclastic density currents (PDCs) were generated during the opening of a large fracture on the SE flank of the SEC cone. The largest PDCs were clearly triggered explosively, and there is evidence that much of the energy was generated during the interaction of intruding magma with wet rocks on the cone's flanks. The most mobile PDCs traveled up to 1 km from their source. This previously unknown process on Etna may not be unique on this volcano and is likely to have taken place on other volcanoes. It represents a newly recognized hazard to those who visit and work in the vicinity of the summit of Etna.

show abstract

Section: Major Pyroclastic Density Currents Generated By Hydromagmatimentioning

confidence: 57%

Pyroclastic density currents resulting from the interaction of basaltic magma with hydrothermally altered rock: an example from the 2006 summit eruptions of Mount Etna, Italy

et al. 2008

View full text Add to dashboard Cite

show abstract

“…During these episodes, large areas of the eastern and southeastern flank of Etna showed displacements of tens of centimeters to meters. Based on detailed observations of the flank slip events, which began in coincidence with the 2002-2003 flank eruption Neri et al 2004Neri et al , 2005aRust et al 2005;Walter et al 2005), we suspect that many of Etna's flank eruptions may be more or less directly triggered or facilitated by flank displacement, as suggested by . However, there are some indications that this interplay between structural instability and flank eruptions has not always been the same as it is now.…”

Section: Structural Role Of the Southeast Cratermentioning

confidence: 87%

The exceptional activity and growth of the Southeast Crater, Mount Etna (Italy), between 1996 and 2001

et al. 2006

Self Cite

View full text Add to dashboard Cite

Between 1971 and, the Southeast Crater was the most productive of the four summit craters of Mount Etna, with activity that can be compared, on a global scale, to the opening phases of the Pu'u 'Ō'ō-Kūpaianaha eruption of Kīlauea volcano, Hawai'i. The period of highest eruptive rate was between 1996 and 2001, when near-continuous activity occurred in five phases. These were characterized by a wide range of eruptive styles and intensities from quiet, non-explosive lava emission to brief, violent lava-fountaining episodes. Much of the cone growth occurred during these fountaining episodes, totaling 105 events. Many showed complex dynamics such as different eruptive styles at multiple vents, and resulted in the growth of minor edifices on the flanks of the Southeast Crater cone. Small pyroclastic flows were produced during some of the eruptive episodes, when oblique tephra jets showered the steep flanks of the cone with hot bombs and scoriae. Fluctuations in the eruptive style and eruption rates were controlled by a complex interplay between changes in the conduit geometry (including the growth of a shallow magma reservoir under the Southeast Crater), magma supply rates, and flank instability. During this period, volume calculations were made with the aid of GIS and image analysis of video footage obtained by a monitoring telecamera. Between 1996 and 2001, the bulk volume of the cone increased by~36×10 6 m 3 , giving a total (1971-2001) volume of~72×10 6 m 3 . At the same time, the cone gained~105 m in height, reaching an elevation of about 3,300 m. The total DRE volume of the 1996-2001 products was~90×10 6 m 3 . This mostly comprised lava flows (72×10 6 m 3 ) erupted at the summit and onto the flanks of the cone. These values indicate that the productivity of the Southeast Crater increased fourfold during 1996-2001 with respect to the previous 25 years, coinciding with a general increase in the eruptive output rates and eruption intensity at Etna. This phase of intense summit activity has been followed, since the summer of 2001, by a period of increased structural instability of the volcano, marked by a series of important flank eruptions.

show abstract

“…After about 15 months of quiescence, a new flank eruption began, late on 26 October 2002, on both the southern and northeastern flanks of the volcano ( Barberi et al 2004;Andronico et al 2005;Neri et al 2005). During the first weeks of the eruption the entire northeastern flank was displaced by several tens of centimeters along the NE Rift and the Pernicana Fault System ( Fig.…”

Section: Structural Framework and Recent Volcanic Activity Of Mt Etnamentioning

confidence: 99%

Evidence of multiple strain fields beneath the eastern flank of Mt. Etna volcano (Sicily, Italy) deduced from seismic and geodetic data during 2003–2004

et al. 2011

Self Cite

View full text Add to dashboard Cite

We carried out a study of the seismicity and ground deformation occurring on Mt. Etna volcano after the end of the 2002-2003 eruption and before the onset of the 2004-2005 eruption. Data were recorded by the permanent local seismic network run by Istituto Nazionale di Geofisica e Vulcanologia -Sezione di Catania and by geodetic surveys carried out in July 2003 and July 2004 on the GPS network.Most earthquakes were grouped in two main clusters located in the northeastern and southeastern sectors of the volcano. The areal distribution of seismic energy associated with the recorded earthquakes allowed us to highlight the main seismogenic areas of Mt. Etna. In order to better understand the kinematic processes of the volcano, 3D seismic locations were used to compute fault plane solutions, and a selected dataset was inverted to determine stress and strain tensors. The focal mechanisms in the northeastern sector show clear left-lateral kinematics along an E-W fault plane, consistent with events occurring along the Pernicana Fault system. The fault plane solutions in the southeastern sector show mainly right-lateral kinematics along a NNE and ENE fault plane and left lateralkinematics along NW fault planes that together suggest roughly E-W oriented compression. Surface ground deformation affecting Mt. Etna measured by GPS surveys highlighted a marked inflation during the same period and exceptionally strong seawards motion of its eastern flank.The 2D geodetic strain tensor distribution was calculated and the results show mainly ENE-WSW extension coupled with WNW-ESE contraction, indicating right-lateral shear along a NW-SE oriented fault plane. The different deformation of the eastern sector of the volcano, as measured by seismicity and ground deformation, must be interpreted by considering the different depths of the two signals. Seismic activity in the southeastern sector of volcano is located between 3 and 8 km b.s.l. and can be associated with a very strong additional E-W compression induced by a pressurizing source just westwards and at the same depth, located by inverting GPS data. Ground deformation, in contrast, is mainly affected by the shallower dynamics of the fast moving eastern flank which produces a shallower opposing E-W extension. The entire dataset shows that two different processes affect the eastern flank at the same time but at different depths; the boundary is clearly located at a depth of 3 km b.s.l. and could represent the décollement surface for the mobile flank.

show abstract

Contrasting triggering mechanisms of the 2001 and 2002–2003 eruptions of Mount Etna (Italy)

Cited by 109 publications

References 30 publications

Pyroclastic density currents resulting from the interaction of basaltic magma with hydrothermally altered rock: an example from the 2006 summit eruptions of Mount Etna, Italy

Pyroclastic density currents resulting from the interaction of basaltic magma with hydrothermally altered rock: an example from the 2006 summit eruptions of Mount Etna, Italy

The exceptional activity and growth of the Southeast Crater, Mount Etna (Italy), between 1996 and 2001

Evidence of multiple strain fields beneath the eastern flank of Mt. Etna volcano (Sicily, Italy) deduced from seismic and geodetic data during 2003–2004

Contact Info

Product

Resources

About