What happens when disaster strikes
The recent devastating tragedies that shook New Zealand and Japan throw some lessons for us who stand in dire need of knowing what happens when tectonic plates show an abnormal movement
EARTHQUAKE BY DR. AFROZ AHMAD SHAH
Earthquakes have always haunted mankind. In the recent past, two devastating earthquakes created death and ruin. One in New Zealand and another in Japan. The earthquake in Japan of was of magnitude 9, which occurred near the east coast of Honshu. To understand why it happened and what caused it, we must understand the geological setup of the area. What we know from our previous geological information is that Japan is included in the Eurasian plate. The pacific plate on its eastern side is subucting under the Eurasian plate and this causes frequent earthquakes. The present one was also because of the regional tectonics. Here it is a result of faulting on or near the subduction zone where the Pacific plate moves approximately westwards with respect to the North American plate at a velocity of 83 mm/yr. What actually happened was that the Pacific plate thrusts underneath Japan at the Japan Trench, and dips to the west beneath Eurasia. The Japan Trench subduction zone, which is tectonically very active, has hosted 9 events of magnitude 7 or greater since 1973. The largest was the one with a magnitude 7.8 earthquake, occurred in December 1994 and caused 3 fatalities and almost 700 injuries. Two recent earthquakes occurred in New Zealand but the one that occurred on the February 21st created more panic. Geologically, it is broadly correlated with the regional plate boundary deformation, where the Pacific and Australian plates interact in the central South Island, and cause frequent earthquakes there, with some reaching a greater magnitude. It however is more complex tectonically and occurred on a plate boundary that changes deformation style. Though, this one was relatively smaller in magnitude (6.3) than the previous one (7.0), which occurred in September, but caused more damage. Possibly, because of the tremors from the previous event, which partly damaged buildings, which were easy for even weak tremors (of magnitude 6.3) to topple down and cause severe damage.
Both of the above mentioned recent examples of devastation occurred in developed countries and caused serious damage in terms of life and property. What if such a high magnitude earthquake were to hit the Kashmir valley? Obviously, we are fortunate for not having an oceanic plate boundary close by which can lead to a tsunami, which is invariably associated with an earthquake. However, Kashmir is tectonically active, which is suggested by a number of active faults in the valley. This activity is because the Indian plate is pushing towards the north, which continuously generates a lot of stress energy along the Himalayan arc and which, is generally released along the faults. A recent study by Susan and her group (2009), published in American Scientist, have written a brief account of Earthquake in the Kashmir Valley. It says, the historical record of earthquakes is not well documented there, and they have faced a lot of hurdles in collecting the reliable evidences. It is partly because of the changes in the location names of towns or villages etc. Their effort to gather past earthquake information is really inspiring and should be done on a larger scale in the near future. They have drawn conclusions based on the hazy historical facts, that one major earthquake is relatively well documented in Kashmir, which occurred in 1555 and possible killed around 600 people. From that date until now, there has not been any major earthquake on record, except one that devastated Muzafferabad, Kashmir, in 2005.
They also stressed that population has increased to about 5 million and the style of building structures has also changed from simple timber houses (less prone to destruction) to concrete buildings (highly prone to destruction, if not designed to resist earthquake shaking).
This study in Kashmir offers some of the facts on, which we must work in the near future. The scarcity of the past earthquake information is really important to understand, if we wish to develop an earthquake hazard map of this region. Without the knowledge of the past earthquakes, it is virtually impossible to warn people about the activity along old faults. Paleoseismology, a branch of earthquake geology offers comprehensive answers to shaky and hazy historical facts.
It is a robust scientific study, which can unearth the hidden information of past earthquakes and with highly accurate results. Remember, when an earthquake hits any place, it often places its imprints in the sediments or rocks, rivers, towns etc, these evidence can be translated scientifically through this kind of study. Further, the information and accurate account of new faults need to be mapped throughout the valley.
One key thing that we learned from all the major destructive Earthquakes around the world is that the “structures” kill people not the earthquakes. The devastation of buildings and structures is the major cause of casualties in the world e.g. the recent Haiti earthquake (2010) and Muzafarabad earthquake, Pakistan (2005). Therefore, earthquake resistant structures are required to minimize the effects of such catastrophes. It is highly recommended by earthquake scientists that constructions in tectonically active regions should be undertaken in due consultation with structural engineers, so that they can guide people to make earthquake resistant structures. This however, is not currently practiced in most of the world and requires a major and significant role of geological scientists to make this possible. But, because of increasing populations, it becomes extremely hard to keep a balance and rely on the engineering advice for construction of various buildings. This is because of the lack of proper engineering advice and a complete lack of exposure to the geological education to the public at large. Even today, a lot of people in most of the countries still believe that natural calamities are a kind of punishment in the form of destruction from God for evil practices performed in their societies!, Kashmir region is not an exception. Therefore, they do not care to obtain any kind of advice to build houses etc. One really wonders, when some disease or war kills thousands of people, everyone runs for cure and research facilities all-over the world then rigorously engage to offer assistance and cure, was this not a punishment from God! Why do people have a different outlook when it comes to natural disasters? Obviously, the answer is ignorance, therefore, a lot needs to be done to make people realise the importance of Earth science education and the causes of natural hazards. Geologists have to work harder to pass this message across the masses, apart from engaging in pure research.
To conclude, the future for geosciences to understand the earth systems and mainly the natural disasters is challenging and it is possibly, more difficult in Kashmir valley, keeping in view its political complexity. Though the ride will be bumpy, steep and often full of hurdles and will therefore, require a strong and motivated workforce, mainly from the Valley. A push to include a basic earth science education is highly required in the academic curriculum of our younger generation, so that the complex interaction of the Earth with its surroundings can be understood at an early age. An earthquake research facility, well equipped with Paleoseismological instruments, should be the priority of the government and measures in this regard should be taken without any further delay. It is required and will be extremely useful to understand the fault behaviour, which will greatly improve the earthquake forecasting in Kashmir valley. As we know, scientists are yet to develop a robust scientific tool, which can forecast earthquakes or tsunamis. However, preventive education regarding such events is available. Simply put, prevention is better than cure. There is still a long way to go before we can achieve a comprehensive cure for such maladies; we must work hard to offer better prevention techniques and use a collaborative approach to achieve the same.
(Feedback at firstname.lastname@example.org)
Lastupdate on : Thu, 14 Apr 2011 21:30:00 Makkah time
Lastupdate on : Thu, 14 Apr 2011 18:30:00 GMT
Lastupdate on : Fri, 15 Apr 2011 00:00:00 IST
- MORE FROM OP-ED
DUST, NO VENTILATION LEADS TO RESPIRATORY, SKIN PROBLEMS
ARSHAD M BHAT
Srinagar, Apr 14: Patients admitted in Valley’s only children healthcare institute, G B Panth hospital have developed respiratory and skin problems due to the dust emanating from the ongoing renovation More
- Srinagar City
Residents adopt novel way to protest
‘FIRST IMPRESSION OF UEED TOWARDS MANKIND—GORGE FOR DEATH’
GK NEWS NETWORK Srinagar, Apr 14: Irked by inaction of the authorities to repair a low-lying manhole which has led to many accidents to motorists, the residents of tourist hub of Dalgate have adopted a More
Jammu, Apr 14: The IGP Kashmir, S M Sahai, Thursday declared the north Kashmir Indoor sports festival open. The ceremony was held at Indoor Sports Stadium Baramulla. DIG Baramulla, DIG CRPF, CO 46 More
Bandipora: District Development Commissioner Bandipora, Manzoor Ahmed Lone today distributed cheques worth Rs 45 lakh among the registered fishermen here. The funds were distributed under central More
Of Rs 32200 cr allocation, Rs 10,000 cr utilized
Srinagar, Apr 14: Even as the revised cost of Prime Minister’s Reconstruction Program for Jammu and Kashmir has escalated to around Rs 32,000 crore, the spending has been just 30 per cent for the past More
Sanya (China), Apr 14: China today recorded its recognition of India's "status" in global affairs and said it "supports" its "aspiration" to play a greater role in the world body, a nuanced expression More