Re: Mount Etna Erupts
Laura said:
casper said:
Watch (possibility') Etna explosion live from Italy,link:
http://www.skylinewebcams.com/it/webcam/italia/sicilia/catania/vulcano-etna-sud.html
Very cool!
I wonder if there is any history of earthquakes at a distance preceding or following eruptions of Etna or Vesuvius? Like in Europe anywhere?
I came across a short study (PDF) and listed extracts below but don't know, if it's any help in what you were looking for in information?
[PDF]Volcanic activity before and after large tectonic earthquakes ...
www.eri.u-tokyo.ac.jp/people/.../EggertWalter2009Triggering.pd...
(PDF)
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&ved=0ahUKEwjVke2jr-TMAhWKcT4KHQEIA5IQFgg1MAM&url=http%3A%2F%2Fwww.eri.u-tokyo.ac.jp%2Fpeople%2Fichihara%2Fvp2010plan%2FEggertWalter2009Triggering.pdf&usg=AFQjCNH9Db5m_N24jt8-ZFWU8vM1ZGSp-w
a b s t r a c t
Keywords:
Volcano eruption
Earthquake
Correlation
Stress triggering
The study of volcanic triggering and interaction with the tectonic surroundings has received special attention in recent years, using both direct field observations and historical descriptions of eruptions and earthquake activity.
Repeated reports of clustered eruptions and earthquakes may imply that interaction is important in some subregions. However, the subregions likely to suffer such clusters have not been systematically identified, and the processes responsible for the observed interaction remain unclear.
We first review previous works about the clustered occurrence of eruptions and earthquakes, and describe selected events. We further elaborate available databases and confirm a statistically significant relationship between volcanic eruptions and earthquakes on the global scale.Moreover, our study implies that closed volcanic systems in particular tend to be activated in association with a tectonic earthquake trigger. We then perform a statistical study at the subregional level, showing that certain subregions are especially predisposed to concurrent eruption–earthquake sequences,whereas such clustering is statistically less significant in other subregions.
Based on this study, we argue that individual and selected observations may bias the perceptible weight of coupling. The activity at volcanoes located in the predisposed subregions (e.g., Japan, Indonesia, Melanesia), however, often unexpectedly changes in association with either an imminent or a past earthquake.
***
A well-known sequence occurred in South America wherein the volcanoes Cordón Caulle and Puyehue erupted in Chile just one day after
the large 1960 Valdivia earthquake (Barrientos, 1994; Lara et al., 2004).
Other prominent examples of volcanoes that have been active in association with major tectonic earthquakes are Mount Vesuvius and Mount Etna in Italy (Sharp et al.,1981;Nercessian et al. 1991 Marzocchi et al., 1993; Nostro et al., 1998; Gresta et al., 2005), the Santa Maria volcano in Guatemala (Rockstroh, 1903;Williams and Self, 1983;White and Harlow, 1993), the New Hebrides (Blot, 1976), various volcanoes in Japan (Koyama, 2002), Alaska (Sanchez and McNutt, 2004) and Kamchatka (Walter, 2007), Mount St. Helens in the USA (Lipman and Mullineaux, 1981), volcanoes in Iceland (Gudmundsson and Andrew, 2007), and Kilauea and Mauna Loa in Hawaii (Swanson et al., 1976; Lipman et al., 1985; Walter and Amelung, 2006).
***
1.5.1. Local scale
On the local scale, it was found that, e.g.,
volcanic activity at Mount Vesuvius, Italy, repeatedly correlated with tectonic earthquakes on Apennine faults in the past 1000 years with a 95% correlation confidence level (Marzocchi et al., 1993; Nostro et al., 1998). Similarly, the rate of earthquakes increases before a new sequence of flank and/or summit activity initiated at Mount Etna and can therefore be seen as a precursor to volcanic activity (Marzocchi et al., 1993); further details on the correlation of Etna eruptions with earthquakes are elaborated by a number of other authors (Sharp et al.,1981; Patane et al.,1994;DeRubeis et al., 1999; Gresta et al., 2005). For the Hawaiian volcanoes, local scale interactions are also suggested to occur (Furumoto, 1957), confirmed by later workers (Decker et al., 1995; Walter and Amelung, 2006). It was found that the probability of concurrence is very high if voluminous eruptions and earthquakes of MN6 are involved (Walter and Amelung, 2006). Numerous other case studies describe volcano-earthquake interactions on the local scale (see table 1), yet the databases are often not large enough to distinguish between coincidence and causality.
***
1.2. Mechanisms responsible for earthquake–eruption sequences
A number of different mechanisms have been proposed to explain the concurrence of eruptions and earthquakes, focusing on triggering processes related to permanent (static) and transient (dynamic) stress and strain changes (Hill et al., 2002; Manga and Brodsky, 2006).
Permanent changes at volcanoes are caused by static dislocation of the crust during an earthquake, which is the best studied and most
commonly suggested mechanism. For instance, compressive permanent deformation at a volcano may lead to the so-called “toothpaste”
or “flask” process, and affect the shallow magmatic system or even deeper reservoirs by squeezing magma out of a chamber, leading to a magma migration and finally to a volcano activity change. Rikitake and Sato (1989) used such a process to explain eruptions at the Izu– Oshima volcano and major inter-plate earthquakes occurring at the Sagami trough west of Japan. The toothpaste model, however, has
been debated because a) the volumes of magma mobilization in a simple elastic medium may not be sufficient to lead to eruptions
and b) compression and extension have both had detectable effects. The latter was demonstrated by volcanoes that began erupting after
earthquake-induced compression (e.g., Mount Pinatubo (Bautista et al., 1996),
Mount Vesuvius (Nostro et al., 1998)), while there are also plenty of examples that suggest that volcanoes became active due to earthquake-induced decompression (e.g., Cerro Negro in Nicaragua (La Femina et al., 2004)). On a larger scale, subduction megathrust earthquakes that usually induce volumetric decompression along the volcanic arc are followed by an increase in volcanic activity (Walter and Amelung, 2007). Intriguingly, permanent deformation may promote volcanic activity even if the thrust earthquake is aseismic (silent) (McNutt and Marzocchi, 2004). Historical records suggest that, in the case of earthquake-induced decompression, open system volcanoes are less affected by remote earthquakes than volcanoes that are closed and have had a long period of quiescence (Walter, 2007; Walter and Amelung, 2007). Material heterogeneities may also contribute to these mechanisms, as shown for Iceland, where soft volcanic zones are subject to large deformation during loading of a seismic zone, whereas stiff zones concentrate stress (Gudmundsson and Brenner, 2003).
A brief history of epidemic and pestilential diseases; with the principal phenomena of the physical world, which precede and accompany them, and observations deduced from the facts stated. : In two volumes.
A brief history of epidemic and pestilential diseases; with the principal phenomena of the physical world
http://quod.lib.umich.edu/e/evans/N27531.0001.001/1:21?rgn=div1;view=fulltext
SECTION XII. Of the Influenza, or Epidemic Catarrh.
AS the catarrh appears to be the disease which is most close|ly connected with pestilence, and the least dependent on local causes or the sensible qualities of the air, I have collected all the well-defined instances of this epidemic which have occurred to my researches, and arranged them in chronological order; pla|cing against the year the most remarkable physical occurrences, and mentioning those which fell within the years next preceding and following:
Page 32
A. D. CATARRH EPIDEMIC IN
1174, the year before an eruption of Etna, and followed by great mortality. [Chasm in the accounts of this disease.]
1510, the same year with an eruption in Iceland, and following great earthquakes. Humid air—a comet appeared the next year. [Chasm.]
1551, the year after an eruption of Etna, and a comet. Season wet.
1557, the year after an eruption of Etna. Season mostly wet; but in some countries dry; a comet the same year. [Chas.]
1580, the year after an eruption of Etna. Cool dry north wind —A comet.
1587, the same year with an eruption in Iceland—and after a comet.
1591, after earthquakes in 1590, and a comet.
1597, the year after earthquakes and a hard winter; rainy sea|son, and a comet the same year.
1602, the year after earthquakes, volcano and severe winter. Cold and wet season.
1610, the year after an eruption of Etna, a comet and severe winter. Season very hot and dry. [Chasm.]
1647, First catarrh mentioned in American annals. The same year with violent earthquakes in South-America. A comet.
1650, In Europe the same year, with an eruption of Etna and earthquakes.
1655, in America, same year with violent earthquakes in South-America, and eruption of Vesuvius.
1658, in Europe, after a severe winter; summer cool.
1675, in Europe, while Etna was in a state of explosion; mild winter.
1679, 80, in Europe, during or just after the eruption of Etna; wet season and a comet.
1688, in Europe, same year with an eruption of Vesuvius, after a severe winter and earthquakes; this began in a hot sum|mer.
1693, in Europe, same year with an eruption in Iceland, and great earthquakes; cool season.
1697, 8, in America, after a great earthquake in Peru; a co|met the same year, and severe winter.
1699, in Europe, in spring; great earthquakes the same year, and a comet.
1708, 9, in Europe, in a severe winter, after a comet and volcano.
1712, in Europe, the same year with an eruption of Vesuvius and a comet; wet season.
1717, in Europe, the year of a comet, eruption of Vesuvius, and a severe winter.
1729, 30, in Europe, the same year with an eruption in Iceland and Vesuvius; dry summer; a comet.
1733, universal, after a comet, a severe winter and great earth|quakes.
1737, in Europe and America; an eruption of Vesuvius, great earthquakes and a comet.
1743, in Europe, violent earthquakes.
1744, a comet; earthquakes.
1747, in America and Europe, with a comet and eruption of Etna.
1755, in Europe, with violent earthquakes and eruptions of vol|canoes, and severe winter.
1757, in America, soon after a comet, and followed by an earthquake.
1758, in Europe, followed by earthquakes the next year.
1761, in America; an earthquake during its prevalence.
1762, in Europe, before an eruption of Etna; a comet the same year.
1767, in Europe; an eruption of Vesuvius the same year, and of Etna and Heckla in the preceding year, with a comet and earthquakes.
1772, in America, after an eruption of Vesuvius and Heckla, and a severe winter.
1775, in Europe, preceded by earthquakes, small eruption of Lipari the same year, and in New-Spain.
1781, in America, the year after an eruption of Etna, and a most rigorous winter.
1782, in Europe and Asia, the year before the great eruption of Heckla.
1788, in Europe, soon after eruptions of Vesuvius and Etna, and earthquakes.
1789, in America, with an eruption of Vesuvius, just after a great earthquake at Iceland and in Europe; warm summer; mild winter followed.
1790, in America, after a mild winter.
1795, in England, after an eruption of Vesuvius and a severe winter.
1797, in Europe, after earthquakes; a comet the same year.
The accounts of the seasons are mostly from English writers, and refer to England, with some exceptions. In regard to heat and cold, the seasons are generally uniform in most countries, on the same continent; but not in regard to drouth and moisture.
Of these forty-four instances of influenza, it may be observed, from the preceding history.
