Seismic history of the Maltese islands
The stresses caused by the movements of the oceanic crust builds up energy which is released through seismic activity. The Maltese Islands are completely composed of sedimentary rocks, and no evidence of igneous rock has been found. The Islands are however surrounded by a number of active or dormant volcanoes. To the north are Mt. Etna (Sicily); the volcanic islands of Stromboli and the Lipari Islands; Mt. Epomeo (Ischia, Bay of Naples); and Mt. Vesuvius, Mt. Albani and the Phlegraean Camps (Italian Mainland). To the northwest of the Maltese Islands lie the submarine Graham volcano and the young volcanic island of Pantelleria. To the southwest are the volcanic islands of Linosa and Lampione; while much further away to the east is the Santorin volcano.
Some recorded earthquates which have in the past affected the Maltese Islands were accompanied by volcanic eruptions. In January 1693, an earthquake felt in Sicily and Malta was accompanied by the eruption of Mt. Etna. A previously quiescent Mt. Etna let off huge volumes of smoke during the widespread earthquake of October 1856. On September 1911, a locally felt earthquake appeared to have an epicenter in the region of Graham volcano or Pantelleria. Another earthquake with possible volcanic eruption occurred in January 1923. This earthquake was accompanied by a rumbling noise coming from a northerly direction. Flashes of “lightning” were noticed on the sea. The cause was attributed to a disturbance between Malta and the Ionian Islands. Volcanic quakes are normally due to the sudden release of steam or other volcanic gases under pressure and accompany volcanic eruptions. Their origin may lie at considerable depths under the sea and are then termed crypto-volcanic. The above recorded quakes could possibly have been volcanic in origin. However the volcanoes in question are situated a fair distance from the Maltese Islands, and it is very unlikely that their effects would be felt locally. It is more probable that the earthquakes were tectonic in origin, and the volcanic eruptions were the result of the widespread earthquakes in the region.
It would therefore appear that earthquakes felt in the Maltese Islands owe their origin to Global Tectonics. Earthquakes in the immediate region of the Maltese archipelago are rare, and rarer still are earthquakes of sufficient magnitude to cause extensive damage. This is very surprising since the Mediterranean region is an active area due to the young age of the surrounding mountain ranges in one of the earth’s oldest synclinal depressions. Though earthquakes may be a rare occurence in the Maltese archipelago, the disturbances arising from them may occur more frequently than originally thought. One such disturbance is a change in sea-level. In the destructive earthquake of 1693, the sea at Xlendi (Gozo) is supposed to have receeded a whole mile and then rushed back again causing further damage. A sudden recession of water on the shoreline, followed by a giant wave indicates a “tsunani”, resulting from an earthquake with a magnitude of at least 6.5 on the Richter’s scale. A tsunani may occur without the obvious accompanment of a tremor, and may not be identified with a tectonic origin. Such an occurrance took place on the night of July 9, 1973. Fishermen and residents in the Salina Bay area (Malta) reported a marine disturbance, which old fishermen called “il-milghuba”, and which was alleged to have occurred a few years previously. At about 3 am, the sea level went down by couple of feet. A short while later, the sea rose a couple of feet above the normal level, before settling down to its original level. Some boats, especially those anchored in shallow water, were seen resting on the seabed. When the sea rose again, a “rumbling noise” was heard by several people in the area, and the resulting wave covered up normally dry land up to 400 feet inshore. Mt. Etna in Sicily was reported to be very active a few days before.
Tremors in the Maltese Islands are not solely due to tectonic factors. Localised tremors of variable magnitude may be caused by local geological events, such as cave-ins of subterranean hollows – such as the cave-in at Il-Maqluba (Qrendi Malta) on 23 November 1343 and at Bahrija (Malta) which killed a boy and several sheep in 1923; and landslips – such as that which occurred at Ghajn Tuffieha (Malta) in 1980.
Earthquakes that caused damage since 1500
There have been seven strong reported earthquakes in Malta, which have caused some damage, the last in 1923. The Maltese islands are perceived to have a low seismicity but there have been large magnitude earthquakes in the surrounding areas – especially in southern Greece and in Sicily.
10 December 1542
This earthquake is reported in Boschi et al. (2000) to have been felt in the Maltese islands with an EMS intensity of VII. This value is derived from a quotation in the contemporary Chronaca Siciliana del Secolo XVI that states that the earthquake was felt very strongly in Malta and a few one-floor dwellings (casupole) collapsed. It must be said that this was soon after the arrival of the Order and documents are still sparse. Boschi et al. (2000) give the intensity value of VII . Azzaro and Barbano (2000) attribute this event to the Scordia-Lentini graben fault (37.21N, 14.94E) with an equivalent surface wave magnitude of 6.4, a rupture length of 16km and a normal displacement.
The maximum intensity is given as X.
The EMS98 intensity scale, which goes from I to XII, describes, according to a detailed set of benchmarks, the strength with which an earthquake is perceived at a particular site, and is different from the magnitude scale, which calculates the size of the earthquake process itself.
11 January 1693
On 9 January 1693 a 5.9 earthquake shook Eastern Sicily, affecting Syracuse, Catania and many other towns and villages in the surrounding area. The quake was also felt by the people in Malta, who nevertheless suffered no casualties nor damage to their properties. But worse was to come only two days later.
On 11 January 1693, another, bigger tremor began to shake the coastal area of Sicily bordering the Strait of Messina, which separates Sicily from the Southern tip of the Italian Peninsula. The 7.4 earthquake was greater than any previous tremors in the area, and caused greater destruction and loss of life than that caused by Mount Vesivius in 79 A.D.
The 11 January 1693 earthquake, which killed roughly between 60,000 and 93,000 people in Sicily, destroyed many historic cities and sites; 2/3 of Catania’s population died on that day, and the city lost incalculable historic buildings. Over 14,000 square kilometres were affected on mainland Sicily; even cities situated at a fair distance like Palermo, Noto and Agrigento also sustained heavy damages. Huge landslides were followed by a gigantic tsunami which struck the Sicilian coast. At the city of Augusta the large waves caused considerable damage to several galleys belonging to the Knights of Malta who were sailing in the area and which ended up being grounded on the shore.
In Malta, this was the most damaging earthquake that has affected the Maltese islands since 1500. It is extensively documented in the Archives, and is also described in a contemporary book by Shower (1693). The most important selections, relating to the earthquake damage, from the Archives of the Knights of Malta (AOM), the Cathedral Archives, records of the Universita’ and other archives of religious orders, are reproduced in Abela (1969) and Ellul (1993) and referenced in detail. Ellul (1993) includes parts of the reports by a specially instituted commission, which was instructed by the Order to carry out a detailed inspection and assessment of the earthquake damage in Valletta and the nearby harbour cities of Cospicua, Vittoriosa and Senglea.
The commission was accompanied by the chief engineer of the Order, Mederico Blondel and two Capo Mastri. Blondel also carried out an earthquake damage inspection of the island of Gozo and the city of Mdina. The earthquake was strongly felt throughout the whole of the islands.
There was general panic among the whole population and most inhabitants spent a number of nights outside their homes, in tents or underground shelters. No direct fatalities are officially recorded. The earthquake was preceded by a magnitude 5.9 foreshock on the 9 January which was felt in Malta but produced no damage.
In Valletta it is reported that there was not one house that did not need some repair. The facades of some major buildings were detached from the main structure, and needed immediate repair, as they were in imminent danger of collapse. Some churches suffered collapse of, or major damage to their domes and severe cracks in walls. A number of Valletta houses also suffered seriously cracked walls and some had to be demolished because they were in danger of collapse.
In Vittoriosa, Senglea and Cospicua, across the Grand Harbour, the damage was much less than in Valletta. The reports are mainly limited to severe damage in church domes and walls, some of which had to be demolished.
Serious damage was done to the old mediaeval city of Mdina, on the island of Malta. Here the Cathedral suffered partial collapse and many other buildings suffered serious damage. It should be noted that there are several remarks in the reports that show that many of the buildings in the city were very old and had been neglected for many years. In particular, the 13th century cathedral was already showing serious signs of disrepair before the earthquake, and plans had in fact already been drafted for its rebuilding before 1693. One part of the cathedral that had already been replaced, the choir, in fact escaped damage in the earthquake. Other buildings in Mdina that were damaged were the Banca Giuratale, many bastion walls and the bridge leading into the city, whose arches were cracked.
The church of St. Paul in Rabat, also suffered severe damage when its bell tower and the apse of the choir collapsed and other parts were damaged. Damage also occurred to the Dominican Friary.
In Gozo, Blondel notes that the damage to the fortified Cittadella, was most probably due to «long years of neglect», as was the damage to coastal towers. The Cathedral in Rabat lost its bell-tower, and other churches sustained damage to their domes and spires, and parts of cliff faces are reported to have been detached and fell to the sea.
On the basis that some buildings suffered damage of Grade 4 in the areas of highest effects, but reflecting a degree of uncertainty in the vulnerability of the buildings, this earthquake has been assigned a local maximum intensity of VII-VIII. This agrees with the intensity assigned by Boschi et al. (2000).
This event, of maximum intensity X-XI in Eastern Sicily, is assigned a moment magnitude and surface wave magnitude of 7.4 in CPTI04.
Azzaro and Barbano (2000) attribute this earthquake to normal faulting on the northern segment of the Malta Escarpment, with a rupture length of 41 km. Barbano and Rigano (2001) revise the CPTI04 estimate to 7.1 using EMS rather than MCS intensities. The event produced a tsunami along the eastern coast of Sicily, which was also reported in Gozo (de Soldanis, 1746). The tsunami has been modelled by Piatanesi and Tinti (1998), confirming the normal faulting nature of the source just offshore Augusta.
The 1693 earthquake consequences on Mdina
Malta felt the outer ripples of the 1693 earthquake which caused such extensive damage in Sicily. Thousands of people were killed in Syracuse and Catania. On 11 January the tremors were felt in all parts of Malta and Gozo. Panic and fear swept throughout the islands. Many people stayed outside their homes, and passed the night in the open: the people of Valletta stayed ‘nel piano della Floriana’ while the people of Senglea took refuge on the galleys and other ships. Others put up tents outside the walls. No deaths were caused by the actual earthquake but some people died later because of injuries incurred by falling masonry. On the other hand, a considerable number of Maltese who were in Sicily lost their life because of the earthquake. In the following months the Order set up a Commission of architects to report on the damages.
Mdina before the 1693 earthquake
At Mdina, a large section of the town was severely shaken. The old mediaeval Cathedral suffered considerable damage but it was not totally destroyed. The decision to replace it had already been taken in 1682. The earthquake simply hastened its demolition. The new Cathedral was designed by the Maltese architect Lorenzo Gafà on a richly decorated baroque style. It took only five years to build: from 1697 to 1702. The cupola was ready in 1705. Gafà was also responsible for the Gozo Cathedral (1711) and for some other fine churches in the villages.
Since parts of the site of the previous Bishop’s palace had been needed for the new Cathedral, the Cathedral Chapter had to provide new quarters for the local Bishop. This work was carried out during the 1710s. The Maltese Diocese was in sore need of a building to house its seminary which had started functioning at Mdina in 1703. The then Bishop of Malta Fra Paul Alpheran de Bussan assisted by Grand Master Manoel de Vilhena, embarked on this enterprise. Its corner stone was blessed in 1733 and by 1742 it was ready to receive the first group of Seminarians.
The present Cathedral was built in Baroque style by the Maltese Architect Lorenzo Gafà (1639-1703) on a site previously occupied by the medieval Cathedral. In 1679, the Cathedral Chapter requested the said architect to add an apsed structure to their old Cathedral to house the choir stalls which from the late fifteenth century were inserted in the presbytery of this church. Few years after the completion of this work, the 1693 earthquake caused serious damages to the old Cathedral. However, Gafà latest addition to it withstood bravely this disaster. The Chapter commissioned him to plan a new Cathedral that was to incorporate within it the said choir area. Work on this project started in 1697 and reached its completion in 1705 when work on its cupola came to an end. This marvelous Baroque structure enhances till the present-day this silent city of Mdina.
Most probably, lack of space could have prevented him from providing an apsed-shaped structure at the end of its main aisle over the main door as well as to the two side-aisles of the transept. Such apses formed an important aspect of Maltese Baroque. It is most probable that he faced the same problem in drawing his plan for the Matrice church in Gozo’s Citadel. The interior of the new Cathedral incorporated in it other aspects that had already found their way earlier in local church architecture. Chief among these are the high-attic vaulting introduced in Malta by Franccesco Buonamici when he restructured the rib-vaulting of the Jesuit church in Valletta which, incidentally, introduced the Latin-cross plan pattern during the last decade of the sixteenth century. The Jesuit Architect Giuseppe Valeriano was the master-mind of this project. This plan was, afterwards, adopted in the building of all Maltese parish churches and reached its peak, during the seventeenth century, particularly with the Mdina Cathedral.
Some of the decorations that enhanced the mediaeval Cathedral have been also inserted in this Baroque structure. Chief among which are the present sacristy, built by Bishop Balthassar Cagliares sometime after 1623 as well as the main door that led to the old Cathedral dating back to 1530. This door was, eventually, inserted at the entrance of the said sacristy. Some of the works of art meant to decorate Gafà’s choir still enhance this area. Mattia Preti, apart from decorating its apse with a painting representing St Paul’s shipwreck, he was also commissioned to produce a series of seven paintings including the titular altar-piece figuring the Apostle’s Conversion, and another two portraying the martyrdoms of St Peter and St Paul while the remaining four presented other important episodes which connected St Paul to the Maltese Islands. These paintings were donated to the Cathedral by Canon Antonino Testaferrata when Gafà completed his choir additional sector to the old Cathedral. Other relevant decorative and devotional entities from this old Cathedral are the following, namely, the Baptismal Font placed near the main door of the present Cathedral, donated by Bishop Jaymus Valguarnera sometime about 1495; an early fourteenth century icon of the Blessed Virgin presently inserted on the altar of the Blessed Sacrament chapel on the side of the north transept and a wooden crucifix sculptured by the Franciscan Fra Inocenzo from Petralia Soprana in 1640 and donated to the Cathedral by Bishop Fra Giovanni Balaguer da Camarasa set on the altar of the chapel of relics on the side of the south transept. The original polyptych that once stood on the main altar of the old Cathedral, which is dateable to the early decades of the fifteenth century and has been attributed to the circle of Luis Borassa (1360-1426), is still extant and forms part of the Cathedral Museum’s picture gallery.
The present Cathedral was consecrated on the 8 October 1703, three years before work on the whole structure came to an end. It is highly probable that this ceremony had been carried out at that time in order to enable Lorenzo Gafà witness this important event which crowned his life-long dedication in church building in the Maltese Diocese. He, in fact, died on the 13 February of the following year.
Restoration works undertaken by Grand Master Vilhena
Thirty years after the earthquake Grand Master Manoel de Vilhena (1722-36) decided to undertake a comprehensive restoration of Mdina to clear the remaining damaged buildings and to give some life to the old city since it had been losing its population who preferred to go and live in the villages.
Between 1723 and 1728 the fortifications were remodelled and repaired, some alterations were made to the street plan of the town and new public buildings were built on French baroque style. Nearly all these buildings were designed by the Parisian architect Francois de Mondion who introduced the French baroque building style to Malta. The old mediaeval square in front of the old Cathedral was enlarged to make more space for the new Cathedral, the Bishop’s Palace and the Banca Giuratale (or Municipal Palace). In 1727 Grandmaster Manoel Vilhena issued a decree for the repopulation of Mdina. An intense building activity followed which transformed Mdina from a neglected old town into a magnificent French-baroque style citadel. Building continued well into the 1730s. The last buildings to be completed were the storage magazines close to Greeks Gate (1739).
Unfortunately, all these projects failed to lure people to go to live in Mdina. Population figures for Mdina for the 18th and 19th century remained low.
20 February 1743
This earthquake coincides with a M 6.3 event in the Lower Ionian Sea, which also inflicted damage in the Italian peninsula, with a maximum intensity of IX on the Adriatic coast (Stucchi et al., 2007), and was felt as far away as north western Italy.
The local historian de Soldanis (1746) reports that «… at 5:30 pm a strong earthquake shook the Maltese islands. It lasted 7 min. It did great damage to both islands. In Gozo, St. George’s Church, St. James Church and the chapel of Our Lady at Qala were badly damaged.
In Malta, St. John’s at Valletta, Mdina Cathedral and numerous other churches were heavily damaged. The Chapel of The Holy Name of the Blessed Virgin – Tal-Virtu’ Rabat (Malta) suffered considerable damage. It had just then been rebuilt and had been blessed on the 26 December 1733. At Wardija in Qala, Gozo, the people reported that they saw the ground rise and fall with such force that the soil was left floating in the air, causing a mist like a fog for a long time. Many sections from hills in Gozo crumbled.»
In the dedication of his book, de Soldanis also mentions this event when he thanks the Bishop of the time, Mons Paolo Alpheran de Bussan, for his generosity in «donating objects made of silver and gold to pay for the repair needed because of the damage caused by the 1743 earthquake».
A document in the Cathedral Archives, Mdina (ACM, Misc., MS62) describes how the coppolino (small dome) of the cathedral collapsed into the church, the rear side of the choir was destroyed and the bell towers heavily damaged, and all the sides of the Cathedral suffered serious cracks, such that «no one dared enter the Cathedral, not even the bell ringer dared go near the bells» for fear of collapse. In the Minutes of the Cathedral Chapter (ACM, Min.Cap. vol. 7), a report by a team of 6 architects commissioned to inspect the damage caused to the Cathdral in Mdina details the damage done to the church, in particular the dome and choir, and recommend methods of repairing the damage.
In particular, Giacomo Bianco described four approximately 3 cm-wide cracks running down the length of the dome, the dislodging of most stones of the dome, and serious damage to the walls of the choir.
This event has been assigned an EMS-98 intensity of VII.
12 October 1856
This earthquake corresponds to the destructive earthquake that occurred in Southern Greece, near the island of Crete. It was one of the largest to occur in Greece, causing destruction and much loss of life in the epicentral area. Its magnitude is given as 8.2 in the NEIC catalogue, and 7.7 in Papazachos et al. (2000). Woo (1995) discusses the effects of this earthquake on the Maltese islands in some detail in the context of anomalously high intensity observed at large epicentral distances. He notes that the distance to Malta is around 1000 km, which would be expected to yield intensities of IV or V, however the damage done corresponds to a considerably higher intensity, which he attributes to the effect of long-period shaking. This was one of the strongest shocks felt on the islands and its effects are well documented in most of the local newspapers of the days following the earthquake, mainly Il Portafoglio Maltese, L’Ordine and The Malta Mail. It is clearly reported that the earthquake woke up inhabitants all over the islands, and caused them to rush out of their houses during the night. Inhabitants inside houses lost their balance. The tremor was accompanied by a loud rumbling, and overturned objects and moved furniture. The duration of the shaking was variably reported to have lasted between 22 s and 60 s. Almost all houses in Valletta, and many houses in other villages and in Gozo suffered serious cracks to their walls, and the damage was more noticeable on the upper floors. Many churches on both islands suffered damage to their domes and walls, or detached crosses and other fixtures.
The dome and sides of St. George’s church in Victoria, Gozo were left «wide open» with detached blocks of stone. Parts of the dome of the Cathedral in Mdina collapsed into the interior. The damage to this Cathedral was estimated at over £ 1000. The steeple of the Carmelite Church in Mdina was so damaged that it had to be rebuilt. The side of the Annunciation chapel on Tal-Gholja hill near Siggiewi collapsed. In Gozo, a signal tower collapsed, and even newly built houses suffered damage. There are also references to the collapse of a chapel on Filfla Island (a minor island off the southern coast of Malta), and that of a coastal tower at Mellieha (Ghajn Hadid Tower). The earthquake was also felt in Southeastern Sicily and caused damage to churches in Pozzallo, and some slight damage in Syracuse (Malta Mail, 18/10/1856).
The effects of this earthquake on people, objects and buildings are documented well enough for a good intensity estimate to be made. Considering that many buildings appeared to have suffered damage of Grade 3, the earthquake has been assigned an intensity of VII.
27 August 1886
This event was felt throughout the Maltese islands, as well as throughout Sicily and Southern Italy, as reported in various telegrams sent to Malta from these localities and reproduced in local newspapers.
In Malta, newspapers report a general panic, with most of the population having been awakened, and rushing out into the streets.
L’Ordine (01/09/1886) reports that in Valletta the Court of Justice, some churches and many houses suffered damage, as well some buildings and the Cathedral in Mdina, but «come dicono, non sono danni molto gravi» (damages are not very serious).
On the other hand, the Malta Times (28/08/1886) reports that «the damage done to many buildings in the city is in some cases very serious», The Superior Court has «been rendered unsafe by the splitting of the keystone and roof. «The upper part of a coffee shop in Strada Reale also presents several apertures». A number of houses in Valletta, and the choir of St. John’s Cathedral, are also reported to have been damaged, although the nature of the damage is not specified. In Mdina, the Cathedral and some churches suffered damage. In particular, «the Military Sanitarium at Citta Vecchia has suffered most severely, one crack extending from end to end of the building, through a wall of about 25 feet in thickness» (Malta Times, 03/09/1886).
This event almost certainly corresponds to a magnitude 7.5 earthquake in the Aegean Sea on that day at 21:32 GMT (Papazachos et al., 2000), although there is slight conflict with the origin time. The Malta Times reports that «… just as St. John’s Cathedral had boomed out the hour of 11, a rumour was heard, the source or cause of which one had hardly time to consider, when we were brought to a knowledge of our terrible position, by a fearful rumbling noise, accompanied by a slight vibration of the Earth which increased in intensity until the heavens seemed to rend the twain, and the ground to sway from beneath our feet. 70 s of fearful suspense, held almost every inhabitant of the Island, in a state of utter bewilderment, which was further intensified by a recurring shock, of force and duration if anything, exceeding that of its predecessor.» The onset times reported in the various telegrams from Greece and Southern Italy also vary quite widely. The event has been assigned an intensity VI-VII.
30 September 1911
This event produced distinctly different intensities in the two islands of Malta and Gozo. The local newspapers report that most damage from this event occurred on the island of Gozo. The Italian language newspaper Malta (02/10/1911) gives a good account of damage to this island. Serious cracks appeared in the domes and steeples of several churches, especially in Victoria, Nadur and Gharb, as well as in the walls of several public buildings in Victoria.
Many houses in other villages also suffered «danni non indifferenti» (significant damage) Several rural constructions (single-room stone buildings) were «completely destroyed» and some crosses and statues collapsed. The Daily Malta Chronicle (02/10/1911) reports that «at Fort Chambray (Gozo) there is a great long crack running across the square. All the walls of the barrack rooms are cracked, and numerous holes appear in the ground, one of them three feet wide and of inconceivable depth», and that «the hospital, which was happily empty, the mortuary and linen house are completely wrecked, and although the walls are standing their condition renders the occupation of the buildings unsafe» (Grade 3 damage). Some landsliding was also reported.
In Gozo, everybody abandoned their houses. Some furniture was overturned and some pendulum clocks stopped (Malta, 02/10/1911). The tremors are reported to have been accompanied by a «loud rumbling».
In Malta, on the other hand, the damage was apparently limited to some cracks (Grade 1 damage), although the shaking was strongly felt and caused alarm.
The well-described damage corresponds to EMS-98 intensity VII on the island of Gozo, whereas on Malta, the intensity has been assigned as V.
Although no epicentral location exists for this event, some conclusions may be reached regarding its source parameters. The event was recorded on the seismograph in Catania and Riccò (1911) records an S-P time of 29 s. At Catania, the tremor was only slightly perceived.
The S-P time places the epicentre at around 200 km from Catania, and since the tremor does not appear to have been felt in more northern parts of Sicily, and was felt much more strongly in Gozo than in Malta, it is likely that the epicentre was in the Sicily Channel to the north west of Gozo, possibly on one of the faults bounding the Malta Graben. The shock was also felt at sea in this area. The captain of the Danish ship Calypso reports that at latitude 36.2N and longitude 14.1E (about 20 km north west of Gozo) at 09:23 local time, «a slight agitation of the sea and a tremor» was felt, «enough to influence the movement of the ship» (Malta, 02/10/1911).
18 September 1923
This event is well described in the local newspapers (Malta, Daily Malta Chronicle), and was also recorded on the Milne seismograph in Valletta. Unfortunately, the seismogram did not yield useful information since the shock appears to have thrown the mechanism out of alignment.
The majority of the population took to the street in panic in both islands, although the shock appears to have been felt most strongly around the harbour area in Malta (Daily Malta Chronicle, 19/09/1923).
Damage reported was mainly nonstructural, such as collapses of stone crosses on churches, cracks in church domes, the most serious being that of St. Paul’s church in Rabat, and cracks in the walls of many residential and commercial buildings. This damage may be considered as of Grade 2, and the local site intensity has been assigned as VI.
The earthquake was reported to be slightly felt in Syracuse, Sicily, but is not listed in any of the catalogues. It can therefore be assumed that this is a «Sicily Channel» event, possibly on the Malta Escarpment, given that it was more strongly felt to the east of Malta. The Daily Malta Chronicle reports that «We are authoritatively informed that the disturbance must have occurred some 50 or 60 miles away from the Island.» The ISC bulletin lists it as 35.5N, 14.5E, about 35 km south of Malta, with no other information, however, for this period, location of earthquakes deriving from instrumental data is unreliable.
reference: Pauline Galea ‘ANNALS OF GEOPHYSICS’ , VOL. 50, N. 6, December 2007
Some tremors felt in Malta since 2000 that did not cause damage
21 March 1972
Though felt in 1972 but it is worth mentioning this tremor which many Maltese still remember and talk about.
At 11.06pm on 21 March 1972 an earthquake measuring 4.5 on the Richter scale occurred in the Sicilian Channel. Many slept through it, though many more ran terrified into the streets. Many people gathered in open spaces like Ta’ Qali, Spinola and the Granaries Floriana.
The earthquake produced intensity V on the EMS98 (European Macroseismic Scale). The EMS98 intensity scale, which goes from I to XII, describes, according to a detailed set of benchmarks, the strength with which an earthquake is perceived at a particular site, and is different from the magnitude scale, which calculates the size of the earthquake process itself.
3 February 2001
A tremor was felt in Malta on 3 February 2001, when a slight earthquake took place in the seabed about 12 kilometres off Birzebbuga.
22 January 2002
The aftershock of an earth tremor off Crete was felt in parts of Malta on 22 January 2002 at 6.00am.
A strong earthquake, measuring 6.2 on the Richter scale, jolted the islands of Crete and Rhodes, causing widespread panic but no injuries or damage. The epicentre was in the sea between the islands of Astypalea and Kos at a depth below the seabed.
People from areas like Msida, Qormi, Sliema and Fgura felt the tremor.
About 10 small earthquakes take place in the sea around Malta every year, practically none of which is felt on the islands. In the central Mediterranean areas, there are a considerable number of geological structures which could lead to some minor tremors. The chances of Malta ever experiencing a strong earthquake are low because the island is not located on what is known as a plate boundary, an area susceptible to earthquakes.
Malta experienced something similar to this slight tremor in 1997 when the island felt the aftershock of a massive earthquake which devastated parts of Greece.
8 August 2002
A tremor was felt on 8 August 2002 at 4.50pm following an earthquake on the seabed 20 kilometres north of the island.
The tremor measured 3 on the Richter scale and was felt at 4.58pm. The police said no structural damage was reported, although they too felt the earth shake.
The tremor was felt by a number of people living in Birkirkara, Lija, Valletta, St Julian’s and Mriehel, among others. Some thought it was a fireworks factory explosion. This tremor was the fourth registered in Malta in recent months, though it was the second “local” earthquake.
A moderate underwater earthquake near southern Greece was felt in different areas of Malta in May, registering 5.3 on the Richter scale. Another tremor, measuring 3.5, was registered on January 30, after a quake occurred on the seabed about 10 kilometres off the south-east coast of Malta in the direction of Marsaxlokk. A week earlier, the aftershock of an earth tremor off Crete was felt in parts of Malta.
7 July 2003
Malta was jolted by an earthquake on 7 July 2003 in the afteroon sending people scurrying out in panic into the streets and then jamming the mobile phone system as they contacted relatives and friends.
The earthquake took place at 5.08pm measuring nearly four on the Richter scale, with its epicentre 30 km to the north of the island.
No injuries or structural damage were reported but buildings were felt to rise and settle back in the two short but sharp shocks that were felt in split seconds. The magnitude was above average of the normal tremors, and the sharp trembling was felt all over the country because of the epicentre’s close proximity.
Many people initially thought the shaking was the result of a fireworks factory blast but there had been no loud explosion and it soon became clear that the jolt was caused by an earthquake. People in many areas rushed out into the streets to seek open spaces, fearing the worst. Many, especially the elderly, were overcome and could be seen crying.
The mobile phone system was jammed for around 20 minutes as people frantically called families and friends to ask whether they had felt the tremor.
One woman who was in the basement of a St Julian’s hotel said she heard a loud rumble and the building shake violently. A man from Gzira claimed that items lying on top of his television set crashed to the ground.
24 November 2006
An earthquake measuring 4.9 on the Richter scale was felt across Malta and Gozo on Friday 24 November at 5.45am. The earthquake occurred in the Central Mediterranean and it’s epicenter was located approximately 155 km North West of Gozo.
The Civil Protection Department and the Police received numerous calls from people who felt the tremor, however there have been no injuries or damage reported.
Another two earthquake tremors were felt earlier in 2006, one in January and the other in August
7 January 2008
An earthquake tremor was felt in various localities in Malta on Sunday at about 12.35pm. There were no reports of incidents and injuries. The tremor was reported in various localities in both the south and north of the island. The earthquake produced intensity IV on the EMS98.
The tremor originated from what seems to be an undersea earthquake that hit Greece for about seven seconds and that was registered at 6.9 on the Richter scale. The strong earthquake shook most of Greece and was felt as far away as Egypt and Italy.
The University of Malta’s Seismic Research Unit recorded a 1.5 magnitude earthquake tremor on 16 January at 6.04am, this time much closer to Malta – about 10 km north of Valletta.
14 February 2008
A strong earthquake that rattled southern Greece was felt in various parts of Malta at 11.10am on 14 February 2008. Two earth tremors rattled parts of Malta, the first at 11.09am and the second at 11.38am.
The earthquake’s epicentre was located in southern Greece with a magnitude of 6.7 on the Richter scale and a depth of 30km. It was located some 656 kilometres away from Malta at 37.0 North, 21.7 East. The Seismic Monitoring Unit of the Physics department at the University of Malta reported that the tremor hit the island at 11.10 a.m. It said that a second small tremor was recorded at 11.38 a.m. The department also recorded the strong aftershock.
The earthquake was also felt in the Egyptian capital, Cairo.
The Athens Geodynamic Institute said that the earthquake was off the southern tip of the Peloponnese and measured 6.5 on the Richter scale.
8 July 2008
An earthquake with a magnitude of 3.4 was recorded just 30km west of Gozo on Tuesday 8 July 2008 at 8.13am, the Seismic Monitoring and Research Unit of the University of Malta reported.
On Saturday 5 July 2008 the unit also recorded a smaller earthquake with a magnitude of 1.8 with an epicentre 20km to the south-east of Malta.
7 August 2009
A tremor measuring 3.4 on the Richter scale has been felt in several areas of the country on Friday 7 August 2009. The tremor recorded at 11.06am was located under the seabed 43 kilometres east of Malta.
The tremor was felt by some people in Valletta and elsewhere, but many others did not feel a thing.
In July 2009 the University of Malta’s Seismic Research Unit registered four earthquakes in Malta that ranged between 2.2 and 3.6 on the scale. On Tuesday 3 August 2009, the unit picked up a tremor in Sicily that measured 3.8 on the Richter scale.
12 November 2010
An earthquake having a magnitude of 3.8 occurred about 90 km south of Malta at 4.43am on Friday 12 November 2010.
Another small tremor occurred two days earlier at the same place at 8.22am. Friday’s tremor was the larger of the two.
1 April 2011
An earthquake about 1,000 kilometres away from Malta was felt in several towns around the island just before 3.30pm on 1 April 2011.
The underwater quake occurred 127 kilometres off the north eastern coast of Iraklion, Crete, and clocked 6.1 on the Richter scale. It has been observed that there is more of a chance of Malta feeling earthquakes coming from Greece and that region.
In Malta, the tremor was felt in Valletta, Ta’ Xbiex, Msida, Blata l-Bajda, Sliema and Xemxija.
24 April 2011
On Easter Sunday 24 April 2011windows rattled, doors shook open and furniture vibrated in several homes around the island when a series of earthquakes occurred 37 km east of Malta.
Described as a quake of “average” magnitude, the first tremor, measuring 3.5 on the Richter scale, was mainly felt in the south of the island at about 12.11am. Other quakes followed with a larger one, of 4.1 magnitude, felt soon after Easter lunch just after 3 p.m. This was slightly more powerful than average but still could not be considered to be a big earthquake.
Many of those who felt the first quake described it as an explosion in the distance. One man said he initially suspected it was a fireworks factory that had blown up.
“I felt it faintly in Ta’ Xbiex,” a timesofmalta.com reader wrote, adding: “The bedroom door shook for a second like a blast had occurred far away.” A Żejtun resident said: “I felt something similar to the effects of having a truck starting its engine behind my front door”. A young woman from Qormi woke up to the sound of vibrations and her mother, who was in another room, said it was as though there was something in her wardrobe. An Msida woman said she saw water ripples form in her tea cup just after midnight. A woman, who was in Sannat, felt her bed shake and looked under it thinking there was her dog there but the pet was nowhere around. At about 3.03pm, a Marsa man was sitting at his computer when the table started moving during the tremor that lasted a few seconds. At the same time, a woman in Xewxika heard a loud, creaking sound and her home started shaking.
There were no reports of damage and the Civil Protection Department received no calls for assistance.
Some 500 reports were received by the Seismic Monitoring and Research Unit in the Physics Department at the University of Malta through its online questionnaire following the tremors. The unit recorded 16 shocks within an area 34 kilometers east of Malta between April 24-27. The magnitudes ranged from 2.5 to 4.1 recorded on April 24 at 3.02pm.
It appears the public felt four of the recorded shocks: at 12.11am, 11.21am and 3.02pm on April 24, and 6.10am on April 26.
At 12.10am on April 24, Easter Sunday, people from several towns including Qormi, Msida, Floriana, Marsa, Siġġiewi, Valletta, Marsascala and Żabbar experienced a tremor that “rattled windows” and “shook doors”, and shook some people awake. It was part of what is described as an “earthquake swarm” spread across those four days.
11 May 2011
A slight tremor was felt in several localities in the south of Malta on 11 May 2011 in the afternoon.
It was recorded by the seismic monitoring and research unit of the University of Malta, which recorded it at a magnitude of 2.5 south east of Malta in location 35.73N; 14.63E. Another tremor was reported in the same location two days before.
People reported feeling the tremor in Zabbar, Marsaxlokk and Fgura at about 5.15pm.
A set of tremors in the same area off Malta was recorded on April 25-26 with the most powerful reaching a magnitude of 3.5.
18 December 2011
An earth tremor measuring 4.6 on the Richter scale was felt in several parts of Malta on Sunday 18 December 2011.
The tremor took place west of Malta half way between Malta and Tunisia at about 3.30pm.
29 March 2012
A 4.3 magnitude earthquake was registered at 01:17am on 29 March 2012 in Messina Sicily, but its shock waves were registered also in Malta.
The tremor was registered at 124 km N of Catania, 128 km SW of Cosenza, and 305 km N of Valletta. The USGS established the quake at a depth of 238.9 km . There were no significant injuries or damage reported.
3 July 2012
An earthquake in the Central Mediterranean between Libya and Malta was felt in some areas of Malta just after 7.00am on 3 July 2012 with a magnitude of 4.7. It struck south east of Malta in an area 194km from Tripoli.
It was felt in Guardamangia and Msida with a person saying he saw his computer monitor shake.
14 May 2013
An earthquake right in between Malta and Sicily on 14 May 2013 in the afternoon has gone unnoticed by the populations of both islands
The tremor was recorded at 3.51pm and registered 3.3 on the Richter scale. The epicentre was at a depth of 10.4 kilometres to the south east of Sicily or north east of Malta.
The tremor was not felt on either island and no damages were reported
24 August 2013
Tremor as registered at Wied Dalam, Malta, Seismic Centre
A magnitude four tremor struck at Golfo di Noto – Capo Passero, some 99 km away from Malta, on Saturday 24 August 2013 at 7.18 p.m.
The Wied Dalam seismograph registered a strong shock as the earthquake was at a very shallow depth of 10 km. It was a single event and no aftershocks were recorded. No damage was recorded in Sicily, where the tremor was felt.
No one felt the tremor in Malta and Gozo.
26 August 2013
A second earth tremor in as many days was reported on Monday 26 Agust 2013 early morning, close to Gozo.
The tremor struck some 30 km NW of Gozo. The 3.7 magnitude tremor was 10 km deep and struck at 5.45 a.m.
Its magnitude was some three times less in strength than the 4.0 mag. of the 24 August earthquake at Golfo di Noto / Capo Passero in Sicily which was also at the same depth.
Slight tremors were felt at Zebbug Gozo.
12 October 2013
An earthquake with a magnitude of more than six degrees struck near the island of Crete in southern Greece, with reports of damage to houses and shops.
According to the US Geological Survey the quake had a 6.4 magnitude, while the Athens Observatory gave it a magnitude of 6.2.
The epicentre was about 60 kilometres off the city of Hania in western Crete, the state-run Athens News Agency said.
The earthquake struck at 4.11pm on Saturday 12 October 2013 and its epicentre was in the sea, 275 kilometres south of Athens, the Athens Observatory announced, describing the quake as ‘strong’.
‘The quake took place in an area known for its seismic activity.
It was strongly felt in Crete but also in the rest of Greece,’ geology professor Efthymios Lekkas told Skai radio. It was also felt in Malta.
‘It was very impressive because the shaking lasted some 40-50 seconds,’ a woman who identified herself only as Vassia, told a reporter on the island.
According to Skai radio station, houses and shops in Hania were damaged while one person was lightly injured while attempting to jump out a window.
Local media further reported that fallen rocks had blocked a road close to Hania.
15 December 2013
An earthquake with a magnitude of 4.1 struck near sourhern Sicily 104 km NE of Valletta, Malta (36.72N;15.07E) at 3.57am on 15 December 2013 at a depth of 10 km.
It was felt in some localities in Malta but no damage was reported.
4 April 2014
A tremor was felt in various parts of Malta on Friday 4 April 2014 at about 10.10pm. The tremor was felt all over the island, from Gozo to Marsascala. It was also felt in the province of Ragusa.
The cause appeared to be a 5.7 magnitude earthquake 89 kilometres south of Athens. It lasted 10 seconds.
The tremor was registered on the seismic monitoring graph of the University of Malta. The University said the earthquake was 110 km below the earth’s surface in the sea just offshore Southern Greece. The deep earthquake posed no risk of generating a tsunami.
From reports on the SMRU (Seismic Monitoring and Research Unit) online questionnaire, the tremor was felt mostly at localities in the eastern and central parts of Malta. These mostly reported a “trembling” and some rattling of doors and windows but no damage was reported. Many posted comments on the social media to say they felt the earth tremble for a few seconds.
5 April 2014
Another earth tremor was felt in various parts of Malta on Saturday 5 April 2014 at 12.24. It is believed to have been caused by a 4.8 magnitude earthquake some 56km deep near Crotonese in Southern Italy. No damage was caused in Italy or Malta.
The tremor was recorded by the Seismic Monitoring and Research Unit of the University of Malta.