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Recent earth tremors in Sri Lanka

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– a critical review in relation with such activity in Tamil Nadu and the orogenesis of Himalayas based on a new theory of cratons and mobile belts in the Indian peninsular

By DULIP JAYAWARDENA

Former Director Geological Survey Department and retired Economic Affairs Officer, United Nations ESCAP

There were recent reports of earth tremors in the Buttala and Wellawaya areas in Sri Lanka and statements made by local earth scientists failed to give any scientific explanations as regards such activity.

An attempt is made to explain such activity in relation to seismicity in Sri Lanka compared to Tamil Nadu as well as the orogenesis of the Himalayas in relation to a new theory of cratons and fold belts in India and its extrapolation to Sri Lanka.

There was a news item in the local media that if a major earthquake occurs in the Himalayan region there will be tremors felt in Colombo as well as in Jaffna.

Historical seismicity in the Himalayan region has been analysed and its slip potential in the 21 Century recorded (Rodger Bilham roger.bilham@clorado.edu ).

The seismicity of Sri Lanka and Tamil Nadu are compared to understand mountain building in the two regions as Sri Lanka resemble crystalline metamorphic rocks of South India.

It is recommended that the theory cratons and mobile belts that has been postulated in India focusing on the Tamil Nadu region be extended to Sri Lanka to explain present earth tremors in Buttala and Wellawaya areas.

COMPARISON OF ALTITUDES AND SEISMIC RECORDS BETWEEN SRI LANKA AND TAMIL NADU

The highest mountains in Sri Lanka are Pidurutalagala (2524 metres msl), Kirigalpotha (2396 metres msl), and Samalakanda – Adam’s Peak (2243 metres msl)

As compared to Sri Lanka the heights of 77 mountains range from 2695 meters msl to 522 metres msl from the Indian Peninsular.

Tamil Nadu, which is a part of Peninsular India, compared to the highest peneplain of Sri Lanka (Wadia 1945), has three mountains namely Anamuda (2395 metres msl ) , Meesapullimala (2640 metres msl) and Kolabetta (2629 metres msl) -Wikipedia.

Accordingly, it is evident that the highest mountains in Sri Lanka can be closely related to those of Tamil Nadu subject to the same orogenesis or mountain building.

SEISMIC HAZARD ANALYSES FOR STATE OF TAMIL NADU SOUTH INDIA

A study by G. P. Ganapathy Assistant Professor, Centre for Disaster Mitigation and Management VIT University Vellore 632 014 Tamil Nadu India seismigans@yahoo.com and Rajaratnam S. Professor, Centre for Disaster Mitigation and Management, Anna University Chennai 600 025 Tamil Nadu, India ( drrajarathnam@yahoo.com ) have extensively analyzed seismic potential sources of Tamil Nadu State and are summarised in Table 2 of their paper titled, “Seismic Hazard Analyses for Tamil Nadu State: A Deterministic Approach “and published in the Jour. Engr. Geol. Vol.XXXV1 NO1.4

Tamil Nadu State covers 130 ,058 sq. km approximately twice the size of Sri Lanka which encompasses only 65 000 sq. km. Figure 1 gives a large number of lineaments which are seismic prone and it is interesting to note that such lineaments especially in the South Block may extend to Sri Lanka and Figure 2 indicate identified seismic potential sources in this block.

SEISMIC POTENTIAL SOURCES OF TAMIL NADU

Table 1 of the above research paper analyses seven sources seismic potential sources with lengths varying from 315 km to 42 km with cumulative number of earthquakes ranging from 5 to 1 with magnitudes varying from 6.0 to 5.0 (M) observed from historical /instrumental earthquakes and peak ground acceleration (PGA) in g determined using m varying from 0.212 to 0.078 . It is noted that PGA is high in earthquakes with magnitude 6.0 and low in magnitude 3. Further PGA in Chennai, Coimbatore, Salem, Madurai and Tiruchirappalli cities varies from 0.107g, 0.133g, 0.012g ,0.77g and 0.113 g respectively. It is noted that the southeastern part of the State shows high values because of a high earthquake data for the years 1800 to 2004 It also explains that the southern part of the State which may extend to Sri Lanka shows comparatively low seismic hazards.

SEISMIC RECORDS AND POTENTIAL OF SRI LANKA

It is reported that Sri Lanka had no seismic records up to 1800. However from the period 1615 to 1800 earthquakes were reported close to Sri Lanka in the northern Indian Ocean and Coimbatore- Nilgiri Hills. (Seneviratne H.N et al ( DOI :http://doi.org/10.4038/engineer.v53i2.7412)

Newspaper reports are available in the National Archives, Sri Lanka in 1882 ,1924, 1938 and 1944(Ceylon Observer) on earthquakes that had occurred during these years. However no deaths have been reported although there was damage to property (Gunasekera K.W (2000) Sunday Observer ,p34)

Seismic records from 1909 to 1992 were from a seismograph installed in 1909. However, no data are available since 1992 as it was not fully functional.

It is reported that from the year 1823 to 2010 earth tremors and earthquakes in Sri Lanka varied from 5.9 to 3.7 on the Richter Scale and most of such tremors were recorded in the Comorin Ridge Failed Mannar Rift Zone (Seneviratne et.al).

Sri Lanka has been identified as a Mid Plate Platelet lying between Antarctica -India -Africa and Madagascar ( Curry 1984 adopted by Crawford (1974 )and Katz (1978).

In 1823 there was an earthquake of 5.8 Magnitude at Mandawela , in close proximity of Colombo with coordinates 7deg. Lat. and 80 deg. Long. There were no deaths but damage to property were recorded. There was also an earthquake of 5.9 Magnitude at Lat. N 6.5 and Long 79 E close to Kurunegala.

It is interesting to note that Sri Lanka within a latitude of 7.8731 deg. North and 80.7718 East had 18 earthquakes or tremors between the period 1823 to 2010 a period of 187 years. However, the number of tremors of insignificant nature during this period was 670.

SEISMIC RECORDS IN SRI LANKA AFTER 1992

The Geological Survey and Mines Bureau (GSMB) commissioned three seismometers, one at Pallekelle in year 2000 (PALK) connected to the Global Seismic Network (GSN)and the others in 2010 Mahakandarawa (MALK) connected to GEOFON) Network and Hakmana (HALK)connected to GEOFON (Geo-Network operated by Germany).

It is of importance that a network of seismometers be established in Colombo and the Western Province and a network of seismometers covering the entire Island to establish relationship between earthquakes and development activity accelerated recently in Sri Lanka. (Senaviratne H.N. et. al. 2020)

It has also been revealed that an earthquake of magnitude 6.9 (475-year return period) along the Mannar Rift Zone identified earlier in this report.

SRI LANKA HAS THE LOWEST GRAVITY RECORDED IN THE WORLD

The European Space Agency (ESA) carried out a four-and-a-half-year Gravity Field and Steady – State Ocean Circulation Explorer (GOCE) mission to learn what constitutes the surface beneath the Earth and discovered that the lowest negative gravity was south of Sri Lanka.

A geoid is the equipotential surface that coincides over the oceans with the same sea level. It is noted that the earth becomes flattened around the equator and the distance from equatorial areas to the center of the Earth is more than from the poles to the center. (Roar media Sachith Mendis (https://roar.media/english/life/reports/sri-lanka-least-earth-place-world )

It is also revealed that launching of space satellites will be much cheaper due the low gravity and due to no land surface directly south of Sri Lanka.

EARTHQUAKE OF 1615 IN SRI LANKA

An earthquake of magnitude 8 or 9 on the Richter scale was reported on 14 April 1615 evening offshore that caused extensive damage in western part of the Island. The worst hit area was Colombo and 2 per cent of Colombo Fort was destroyed. It has been reported that nearly 200 houses were destroyed with nearly 2000 casualties. Accordingly, moderate sized earthquakes cannot be ruled out in Sri Lanka. (Muhandiram P. M. S. S. B. <https: loes18.wildapricot.org/article _earthquakes-text= According to this document2 % of Colombo Fort got destroyed.

GRAVITY MAP OF SRI LANKA

A Gravity Map of Sri Lanka was compiled and produced in 1975 by the Geological Survey Department (present GSMB) on the scale of 1: 1. 000,000 by T. Hatherton, D. B. Pattiarachchi and V. V. C. Ranasinghe with an appendix by R.B. Evans.

A total of 1,170 points were established covering the whole Island in respect to 19 base stations and about 87 per cent of observations where in areas less than 150 meters msl.

The horizontal distance and heights of the 1971 gravity observations were from 1 -inch topographic maps covering Sri Lanka.

Most of these gravity stations were tied up with the trigonometrical survey stations of the Survey Department. When these stations were opened it was revealed that there was movement due to upliftment.

A contour map of complete Bouguer (gravity anomaly corrected to the height of its measurement) anomalies with the locations of gravity observations was produced.

The gravity map has revealed a negative gravity low on the Highland -Vijayan boundary in the east of Sri Lanka.

(To be concluded)



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Misinterpreting President Dissanayake on National Reconciliation

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President Dissanayake

President Anura Kumara Dissanayake has been investing his political capital in going to the public to explain some of the most politically sensitive and controversial issues. At a time when easier political choices are available, the president is choosing the harder path of confronting ethnic suspicion and communal fears. There are three issues in particular on which the president’s words have generated strong reactions. These are first with regard to Buddhist pilgrims going to the north of the country with nationalist motivations. Second is the controversy relating to the expansion of the Tissa Raja Maha Viharaya, a recently constructed Buddhist temple in Kankesanturai which has become a flashpoint between local Tamil residents and Sinhala nationalist groups. Third is the decision not to give the war victory a central place in the Independence Day celebrations.

Even in the opposition, when his party held only three seats in parliament, Anura Kumara Dissanayake took his role as a public educator seriously. He used to deliver lengthy, well researched and easily digestible speeches in parliament. He continues this practice as president. It can be seen that his statements are primarily meant to elevate the thinking of the people and not to win votes the easy way. The easy way to win votes whether in Sri Lanka or elsewhere in the world is to rouse nationalist and racist sentiments and ride that wave. Sri Lanka’s post independence political history shows that narrow ethnic mobilisation has often produced short term electoral gains but long term national damage.

Sections of the opposition and segments of the general public have been critical of the president for taking these positions. They have claimed that the president is taking these positions in order to obtain more Tamil votes or to appease minority communities. The same may be said in reverse of those others who take contrary positions that they seek the Sinhala votes. These political actors who thrive on nationalist mobilisation have attempted to portray the president’s statements as an abandonment of the majority community. The president’s actions need to be understood within the larger framework of national reconciliation and long term national stability.

Reconciler’s Duty

When the president referred to Buddhist pilgrims from the south going to the north, he was not speaking about pilgrims visiting long established Buddhist heritage sites such as Nagadeepa or Kandarodai. His remarks were directed at a specific and highly contentious development, the recently built Buddhist temple in Kankesanturai and those built elsewhere in the recent past in the north and east. The temple in Kankesanturai did not emerge from the religious needs of a local Buddhist community as there is none in that area. It has been constructed on land that was formerly owned and used by Tamil civilians and which came under military occupation as a high security zone. What has made the issue of the temple particularly controversial is that it was established with the support of the security forces.

The controversy has deepened because the temple authorities have sought to expand the site from approximately one acre to nearly fourteen acres on the basis that there was a historic Buddhist temple in that area up to the colonial period. However, the Tamil residents of the area fear that expansion would further displace surrounding residents and consolidate a permanent Buddhist religious presence in the present period in an area where the local population is overwhelmingly Hindu. For many Tamils in Kankesanturai, the issue is not Buddhism as a religion but the use of religion as a vehicle for territorial assertion and demographic changes in a region that bore the brunt of the war. Likewise, there are other parts of the north and east where other temples or places of worship have been established by the military personnel in their camps during their war-time occupation and questions arise regarding the future when these camps are finally closed.

There are those who have actively organised large scale pilgrimages from the south to make the Tissa temple another important religious site. These pilgrimages are framed publicly as acts of devotion but are widely perceived locally as demonstrations of dominance. Each such visit heightens tension, provokes protest by Tamil residents, and risks confrontation. For communities that experienced mass displacement, military occupation and land loss, the symbolism of a state backed religious structure on contested land with the backing of the security forces is impossible to separate from memories of war and destruction. A president committed to reconciliation cannot remain silent in the face of such provocations, however uncomfortable it may be to challenge sections of the majority community.

High-minded leadership

The controversy regarding the president’s Independence Day speech has also generated strong debate. In that speech the president did not refer to the military victory over the LTTE and also did not use the term “war heroes” to describe soldiers. For many Sinhala nationalist groups, the absence of these references was seen as an attempt to diminish the sacrifices of the armed forces. The reality is that Independence Day means very different things to different communities. In the north and east the same day is marked by protest events and mourning and as a “Black Day”, symbolising the consolidation of a state they continue to experience as excluding them and not empathizing with the full extent of their losses.

By way of contrast, the president’s objective was to ensure that Independence Day could be observed as a day that belonged to all communities in the country. It is not correct to assume that the president takes these positions in order to appease minorities or secure electoral advantage. The president is only one year into his term and does not need to take politically risky positions for short term electoral gains. Indeed, the positions he has taken involve confronting powerful nationalist political forces that can mobilise significant opposition. He risks losing majority support for his statements. This itself indicates that the motivation is not electoral calculation.

President Dissanayake has recognized that Sri Lanka’s long term political stability and economic recovery depend on building trust among communities that once peacefully coexisted and then lived through decades of war. Political leadership is ultimately tested by the willingness to say what is necessary rather than what is politically expedient. The president’s recent interventions demonstrate rare national leadership and constitute an attempt to shift public discourse away from ethnic triumphalism and toward a more inclusive conception of nationhood. Reconciliation cannot take root if national ceremonies reinforce the perception of victory for one community and defeat for another especially in an internal conflict.

BY Jehan Perera

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Recovery of LTTE weapons

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Sri Lanka Navy in action

I have read a newspaper report that the Special Task Force of Sri Lanka Police, with help of Military Intelligence, recovered three buried yet well-preserved 84mm Carl Gustaf recoilless rocket launchers used by the LTTE, in the Kudumbimalai area, Batticaloa.

These deadly weapons were used by the LTTE SEA TIGER WING to attack the Sri Lanka Navy ships and craft in 1990s. The first incident was in February 1997, off Iranativu island, in the Gulf of Mannar.

Admiral Cecil Tissera took over as Commander of the Navy on 27 January, 1997, from Admiral Mohan Samarasekara.

The fight against the LTTE was intensified from 1996 and the SLN was using her Vanguard of the Navy, Fast Attack Craft Squadron, to destroy the LTTE’s littoral fighting capabilities. Frequent confrontations against the LTTE Sea Tiger boats were reported off Mullaitivu, Point Pedro and Velvetiturai areas, where SLN units became victorious in most of these sea battles, except in a few incidents where the SLN lost Fast Attack Craft.

Carl Gustaf recoilless rocket launchers

The intelligence reports confirmed that the LTTE Sea Tigers was using new recoilless rocket launchers against aluminium-hull FACs, and they were deadly at close quarter sea battles, but the exact type of this weapon was not disclosed.

The following incident, which occurred in February 1997, helped confirm the weapon was Carl Gustaf 84 mm Recoilless gun!

DATE: 09TH FEBRUARY, 1997, morning 0600 hrs.

LOCATION: OFF IRANATHIVE.

FACs: P 460 ISRAEL BUILT, COMMANDED BY CDR MANOJ JAYESOORIYA

P 452 CDL BUILT, COMMANDED BY LCDR PM WICKRAMASINGHE (ON TEMPORARY COMMAND. PROPER OIC LCDR N HEENATIGALA)

OPERATED FROM KKS.

CONFRONTED WITH LTTE ATTACK CRAFT POWERED WITH FOUR 250 HP OUT BOARD MOTORS.

TARGET WAS DESTROYED AND ONE LTTE MEMBER WAS CAPTURED.

LEADING MARINE ENGINEERING MECHANIC OF THE FAC CAME UP TO THE BRIDGE CARRYING A PROJECTILE WHICH WAS FIRED BY THE LTTE BOAT, DURING CONFRONTATION, WHICH PENETRATED THROUGH THE FAC’s HULL, AND ENTERED THE OICs CABIN (BETWEEN THE TWO BUNKS) AND HIT THE AUXILIARY ENGINE ROOM DOOR AND HAD FALLEN DOWN WITHOUT EXPLODING. THE ENGINE ROOM DOOR WAS HEAVILY DAMAGED LOOSING THE WATER TIGHT INTEGRITY OF THE FAC.

THE PROJECTILE WAS LATER HANDED OVER TO THE NAVAL WEAPONS EXPERTS WHEN THE FACs RETURNED TO KKS. INVESTIGATIONS REVEALED THE WEAPON USED BY THE ENEMY WAS 84 mm CARL GUSTAF SHOULDER-FIRED RECOILLESS GUN AND THIS PROJECTILE WAS AN ILLUMINATER BOMB OF ONE MILLION CANDLE POWER. BUT THE ATTACKERS HAS FAILED TO REMOVE THE SAFETY PIN, THEREFORE THE BOMB WAS NOT ACTIVATED.

Sea Tigers

Carl Gustaf 84 mm recoilless gun was named after Carl Gustaf Stads Gevärsfaktori, which, initially, produced it. Sweden later developed the 84mm shoulder-fired recoilless gun by the Royal Swedish Army Materiel Administration during the second half of 1940s as a crew served man- portable infantry support gun for close range multi-role anti-armour, anti-personnel, battle field illumination, smoke screening and marking fire.

It is confirmed in Wikipedia that Carl Gustaf Recoilless shoulder-fired guns were used by the only non-state actor in the world – the LTTE – during the final Eelam War.

It is extremely important to check the batch numbers of the recently recovered three launchers to find out where they were produced and other details like how they ended up in Batticaloa, Sri Lanka?

By Admiral Ravindra C. Wijegunaratne
WV, RWP and Bar, RSP, VSV, USP, NI (M) (Pakistan), ndc, psn, Bsc (Hons) (War Studies) (Karachi) MPhil (Madras)
Former Navy Commander and Former Chief of Defence Staff
Former Chairman, Trincomalee Petroleum Terminals Ltd
Former Managing Director Ceylon Petroleum Corporation
Former High Commissioner to Pakistan

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Yellow Beatz … a style similar to K-pop!

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Yes, get ready to vibe with Yellow Beatz, Sri Lanka’s awesome girl group, keen to take Sri Lankan music to the world with a style similar to K-pop!

With high-energy beats and infectious hooks, these talented ladies are here to shake up the music scene.

Think bold moves, catchy hooks, and, of course, spicy versions of old Sinhala hits, and Yellow Beatz is the package you won’t want to miss!

According to a spokesman for the group, Yellow Beatz became a reality during the Covid period … when everyone was stuck at home, in lockdown.

“First we interviewed girls, online, and selected a team that blended well, as four voices, and then started rehearsals. One of the cover songs we recorded, during those early rehearsals, unexpectedly went viral on Facebook. From that moment onward, we continued doing cover songs, and we received a huge response. Through that, we were able to bring back some beautiful Sri Lankan musical creations that were being forgotten, and introduce them to the new generation.”

The team members, I am told, have strong musical skills and with proper training their goal is to become a vocal group recognised around the world.

Believe me, their goal, they say, is not only to take Sri Lanka’s name forward, in the music scene, but to bring home a Grammy Award, as well.

“We truly believe we can achieve this with the love and support of everyone in Sri Lanka.”

The year 2026 is very special for Yellow Beatz as they have received an exceptional opportunity to represent Sri Lanka at the World Championships of Performing Arts in the USA.

Under the guidance of Chris Raththara, the Director for Sri Lanka, and with the blessings of all Sri Lankans, the girls have a great hope that they can win this milestone.

“We believe this will be a moment of great value for us as Yellow Beatz, and also for all Sri Lankans, and it will be an important inspiration for the future of our country.”

Along with all the preparation for the event in the USA, they went on to say they also need to manage their performances, original song recordings, and everything related.

The year 2026 is very special for Yellow Beatz

“We have strong confidence in ourselves and in our sincere intentions, because we are a team that studies music deeply, researches within the field, and works to take the uniqueness of Sri Lankan identity to the world.”

At present, they gather at the Voices Lab Academy, twice a week, for new creations and concert rehearsals.

This project was created by Buddhika Dayarathne who is currently working as a Pop Vocal lecturer at SLTC Campus. Voice Lab Academy is also his own private music academy and Yellow Beatz was formed through that platform.

Buddhika is keen to take Sri Lankan music to the world with a style similar to K-Pop and Yellow Beatz began as a result of that vision. With that same aim, we all work together as one team.

“Although it was a little challenging for the four of us girls to work together at first, we have united for our goal and continue to work very flexibly and with dedication. Our parents and families also give their continuous blessings and support for this project,” Rameesha, Dinushi, Newansa and Risuri said.

Last year, Yellow Beatz released their first original song, ‘Ihirila’ , and with everything happening this year, they are also preparing for their first album.

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