Nepal quake revives appeal to lift ban on US geoscientist

The April 25, 2015 Nepal earthquake has revived an appeal by Indian scientists to lift the ban on US geophysicist Roger Bilham, whose work has largely contributed to the current knowledge of earthquakes in the Himalayan region and who is credited to have catalysed modern geosciences research in India.

Bilham, a geology professor at the University of Colorado, is banned from entering India on grounds of doing science in India while on a tourist visa. On 18 May 2012, Bilham was refused entry at New Delhi airport and put on a return flight to the US¹. Shailesh Nayak, secretary to the Indian Ministry of earth sciences, had said Bilham "engaged in science activity while on a tourist visa” thus necessitating the ban.

However, each time the ground below Nepal trembled last April, India’s geophysicists who have worked with or known Bilham, could not help recall his contribution to the region’s geosciences.

"Bilham has contributed most conceptual elements to our current understanding of the way Himalayan earthquakes are generated," said Vinod Gaur, co-author of several papers with Bilham and former director of the National Geophysical Research Institute (NGRI) in Hyderabad. "Bilham first quantified the deformation in the Himalaya predicated by plate tectonics by analysing the triangulation data of 1913 compared with that of 1980," Gaur told Nature India .

"Later in 1991, he measured 21 sites from one end of Nepal to the other, and discovered for the first time that southern Tibet advances over India at 18 mm/year with a precision of 2 mm. This figure has remained unchallenged till now."

In May 2014, Bilham's request for a conference/business visa to deliver an invited talk at a UK-India workshop on Himalayan earthquakes in Jammu & Kashmir was turned down again. "It cost me $250 to apply for the visa but it was denied," Bilham told Nature India . When contacted, Nayak said he would "look into it". Officials at India’s Ministry of External Affairs did not reply to Nature India 's email seeking to understand the reasons for denial of visa to the US scientist.

Bilham's conceptual model invoking the existence of a ‘locking line’ at the base of the great Himalaya drew attention to the obvious inference that the locked zone in Kashmir Himalaya would likely produce a mega earthquake of magnitude more than 8. "This cautionary note should have elicited a constructive response from scientists and disaster mitigation agencies in India," Gaur said. Instead, the government was advised by a group of scientists to ban his entry, he points out.

C. P. Rajendran, Bilham’s co-author in several papers and one of the scientists who had predicted a major earthquake in the Himalaya in the near future, says, "I have had fierce scientific debates with Bilham throughout my career and some of these disagreements on scientific questions are part of published material. That said, I greatly respect him for his contributions to Indian earthquake science.”

Rajendran, who considers Bilham a pioneer in establishing programmes in GPS-based crustal deformation studies in India and in training a clutch of young Indian geophysicists, says Bilham had only been engaged in activities related to science and research and had not in any anti-national activity. “The ban against him should be revoked in the interest of science and global cooperation. Scientific disagreements should be resolved through debates and shooting the messenger is not the answer,” Rajendran, who feels that the reason behind banning Bilham is not just a visa category issue, says.

Bilham himself believes his deportation three years ago and visa denial last year are a reaction to his publications^2,3 that brought to light seismic risk in Kashmir and at Jaitapur on India's west coast, the proposed site of the country's biggest nuclear plant. Bilham says he has since confirmed from the US State Department that he is on India's blacklist.

"As a result of this denial, it is my understanding that I shall never be allowed back into India," he said. "This is disappointing but it is not the government's fault," he said. "It was caused by just a few people in India." Bilham who declined to name these people said he felt no need to follow this up.

Vineet K. Gahalaut, principal scientist at NGRI, agrees. "If Bilham thinks that an M9 earthquake can occur in Kashmir, and Jaitapur is not safe, we can have a healthy debate on this and can thrash it out. But blocking somebody is not a good idea at all. For the sake of good science, he should be allowed to work in India.”

Geologist Om Bhargava, who has worked extensively in the Himalaya and is currently an honorary scientist at the Indian National Science Academy, feels that science always allows for free discussions and it is not wise to banish a scientist who might hold a divergent view.

The ban on Bilham has also rekindled discussions in the scientific community about the bureaucratic bottlenecks that come in the way of granting visas to foreign scientists. “It is time for the Ministry of Earth Sciences to do something to minimise such bureaucratic procedures,” says Ramesh Singh, formerly at the Indian Institute of Technology in Kanpur and now a professor of earth sciences at Chapman University in California. "The banishment of pioneers like Bilham is sure to affect progress of Indian science.”