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Delhi Skyscrapers Vulnerable To Earthquakes

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Bangalore: Tall buildings in Delhi will come crashing down if a strong earthquake occurs in the northwest region of the Himalayas, warns a research seismologist who had predicted the Sumatran quake that caused the deadly tsunami in 2004.

Buildings taller than 17 metres in the nation’s capital are vulnerable even though the city is more than 300 km away from the Uttarakhand-Himachal region where scientists expect the next high magnitude earthquake, Pune-based Arun Bapat told IANS.

Bapat, formerly head of the earthquake engineering department at the Central Water and Power Research Station, says his warning is based on a careful analysis of damage caused by the 7.9 magnitude Gujarat earthquake that occurred Jan 26, 2001, with its epicentre near Bhuj. 

”Maximum destruction from an earthquake is normally confined to an area of 20 to 30 km radius from the epicentre,” Bapat told IANS.

”However, in the case of the Bhuj quake, extensive damage was caused in Ahmedabad, which is about 320 km from Bhuj.” While tall buildings in Ahmedabad collapsed, the damage was minimal to buildings that had only two or three floors, he says.

The “distance effect” – where the damage is felt far away from the epicentre — is characteristic of “Rayleigh waves” produced during an earthquake, explains Bapat. 

He said there are about 100 tall buildings in the Delhi municipal area and an equal number in the nearby areas of Noida, Gurgaon, Faridabad and Ghaziabad, all of which need strengthening to protect against Rayleigh waves.

Unlike the “P” and “S” waves that travel through the body of the earth and cause damage close to the epicentre, the Rayleigh waves roll along the surface of the earth just like waves on the ocean and cause damage at a distance — typically between 150 to 550 km from the epicentre, he says. 

The damage due to Rayleigh waves occur at a distance because the “amplitude” or strength of these waves is higher far away from the epicentre than closer to it, says Bapat.

A situation similar to what happened in Ahmedabad during the Bhuj earthquake will be repeated in Delhi if an earthquake of magnitude 7.5 or more occurs in Himachal or Uttarakhand, he says.

”Rayleigh waves from such an earthquake would definitely cause heavy damage to tall structures in Delhi and the entire National Capital Region (NCR),” he told IANS. 

According to Bapat, despite the Bhuj earthquake – that wreaked havoc in distant Ahmedabad — the Bureau of Indian Standards (BIS) has not revised the seismic code for tall structures to take into account the likely effect of Rayleigh waves.

The BIS code only provides guidelines for design and construction of buildings to protect them from the adverse effects of “S” waves but not Rayleigh waves, he said.

According to Bapat, during the 8.1 magnitude Mexican earthquake on Sep 19, 1985, Mexico City suffered extensive damage although the epicentre of this earthquake was located at a distance of about 530 km on the Pacific coast.

Again the 8.0 magnitude earthquake witnessed by Pakistan Oct 8, 2005, destroyed the tall buildings in Islamabad although the epicentre of this quake was about 150 km from the Pakistani capital.

These examples from the recent past in addition to the experience of Delhi’s Qutab Minar during the powerful earthquake in the Himalayas Sep 1, 1803 — when two upper floors of the 72-metre tall structure were dislodged — are enough to give an idea of the “distance effect” on tall structures, Bapat said.

Mexico revised its seismic code after the 1985 earthquake damage and many countries including the United States, China and Japan have taken steps to protect the tall structures from possible damage due to Rayleigh waves, Bapat said.

”But the BIS is yet to initiate any action about revision of the seismic code in India,” he said. “If no action is taken immediately, it is quite possible that the scenarios at Mexico City and Ahmedabad may be repeated in the NCR of Delhi.”

Not only Delhi but all cities located at a vulnerable distance from potential epicentres of large magnitude earthquakes should make suitable provisions in the seismic codes, he said.

Other vulnerable cities which could see damage to tall structures from large magnitude earthquakes in northeast India are Kolkata as well as Dhaka and Chittagong in Bangladesh, says Bapat.

”Lahore and Islamabad in Pakistan could suffer from large magnitude earthquakes in the Himalayas and Hindukush while Mumbai and Karachi could possibly suffer damage due to a tsunami produced by an earthquake in the Makran coast.”

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SOUTH ASIA

Pakistani Anti-graft body wants travel ban on Nawaz Sharif, kin

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Pakistan’s anti-corruption watchdog has asked authorities to place ousted premier Nawaz Sharif, his daughter and son-in-law on the Exit Control List to prevent them from leaving the country.

The National Accountability Bureau (NAB) sent a formal request to the ministry of interior. The interior ministry officials confirmed that the NAB wrote that names of Sharif, his daughter Maryam Nawaz and son-in-law Capt (retd) Muhammad Safdar should be put on the Exit Control List (ECL), which listed individuals not allowed to leave Pakistan.

The NAB argued that as the trial of the three nears its conclusion, it is feared that they would leave the country.

Earlier, a similar request to place name of finance minister Ishaq Dar on ECL was not accepted, allowing him to go to London and never return.

Sharif, 68, and his family this week filed an application with the accountability court seeking a fortnight’s exemption from personal appearance from February 19 onwards to let them go to London to see Sharif’s ailing wife. Three cases were filed against Sharif and his family last year, including Avenfield properties, Azizia & Hill Metal Establishment, and Flagship Investments.

Maryam and Safdar are accused only in Avenfield properties case. The NAB had filed two supplementary references against Sharif, his sons Hasan and Hussain regarding Al-Azizia Steel Mills & Hill Metal Establishment and Flagship Investment cases.

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Pakistan “breaches obligations’ on nuclear arms reduction, UN court told

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The Hague: Pakistan is violating its “obligations” to the international community by failing to reduce its nuclear arsenal, the Marshall Islands told the UN’s highest court on Tuesday.

The small Pacific Island nation is this week launching three unusual cases against India, Pakistan and Britain before the International Court of Justice.

Majuro wants to put a new spotlight on the global nuclear threat, its lawyers said yesterday, by using its own experience with massive US-led nuclear tests in the 1940s and 1950s.

“Pakistan is in breach of its obligations owed to the international community as a whole,” when it comes to reducing its nuclear stockpile, said Nicholas Grief, one of the island nation’s lawyers.

Islamabad and its nuclear-armed neighbour India “continue to engage in a quantitative build-up and a qualitative improvement” of their atomic stockpiles, added Tony deBrum, a Marshallese government minister.

DeBrum warned that even a “limited nuclear war” involving the two countries would “threaten the existence” of his island nation people.

Pakistan and India have fought three wars since independence from Britain in 1947, two of them over the disputed Himalayan territory of Kashmir.

In 1998, the rival neighbours both demonstrated nuclear weapons capability.

The ICJ’s judges are holding hearings for the next week and a half to decide whether it is competent to hear the lawsuits brought against India and Pakistan — neither of which have signed the 1968 nuclear Non-Proliferation Treaty (NPT).

A third hearing against Britain — which has signed the NPT — scheduled to start on Wednesday will be devoted to “preliminary objections” raised by London.

The Marshalls initially sought to bring a case against nine countries it said possessed nuclear arms: Britain, China, France, India, Israel, North Korea, Pakistan, Russia and the United States.
Israel has never admitted to having nuclear weapons.

But the Hague-based ICJ, set up in 1945 to rule in disputes between states, has only admitted three cases against Britain, India and Pakistan, because they have accepted the ICJ’s compulsory jurisdiction.

Pakistan’s lawyers did not attend Tuesday’s hearings.

It did however file a counter-claim against Majuro’s allegations saying “the court has no jurisdiction to deal with the application” and insisting that the case is “not admissible”, said ICJ President Ronny Abraham.

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Bangladesh to drop Islam as official religion following attacks on Hindus

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Bangladesh to drop Islam as official religion following attacks on Hindus

New Delhi: Bangladesh is likely to drop Islam as its official religion following a series of attacks on people from other faiths in the country. The country’s Supreme Court is hearing a plea challenging the status of the official religion of the country to Islam.

Bangladesh, which was declared a secular country after its formation in 1971, was declared an Islamic country following a constitutional amendment in 1988.

According to a report in the Daily Mail, the plea has challenged the declaration of Islam as the national religion of the country.

The move is being supported by leaders from the minority communities like Hindus, Christians and Muslim minority Shiites.

Bangladesh has 90 per cent of Muslims, 8 per cent Hindus and remaining constitutes Christians and Muslim minority Shiites.

In last month, a Hindu priest was hacked to death following an attack on a temple in Panchgarh district. Two others were seriously injured in the attack. There have been several lethal attacks on writers and bloggers.

According to a report in the Independent, Islamist groups Jumatul Mujahedeen Bangladesh and Ansarullah Bangla Team are believed to have carried out at least seven attacks on foreign and minority people in Bangladesh in the past year.

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