When earth shakes in J&K

Jammu and Kashmir is a blessed geography. It is known world-wide for its lofty mountains, dense forests, lakes and roaring streams. However, the Himalayan region with unique topography is prone to natural disasters especially earthquakes.           

J&K falls under the high seismic Zones IV and V making it vulnerable to earthquakes. Even a small jolt sends shivers down the spine of people of the mountainous region.

   

On March 21 this year, an earthquake measuring 6.5 on the Richter scale jolted J & K and forced people to rush out of their houses for safety.

The quake brought back horrible memories of the powerful 7.6 magnitude earthquake that rattled J&K on October 8, 2005, claiming 1350 lives and causing massive destruction to structures. 

A study conducted by Roger Bilham, a seismologist and professor of Geology at the University of Colorado at Boulder, United States, has warned that a major quake with magnitude 9 was likely to cause landslides and subsequent major destruction in J&K. But he has not given any timeframe.

There has been an increase in high tectonic activities coupled with soil erosion in quake vulnerable areas in J&K especially Pir Panchal and Chenab Valley.  
           

Experts, who have studied Geomorphology of earthquake vulnerable areas, are worried over drastic changes. Plates have added up huge underground pressure which needs vent to cause tremors.

Kashmir valley embodies a typical geomorphological and active tectonic setup with landforms produced or modified by active tectonic processes with distinct surface expressions. Numerous active faults have been identified in Kashmir with the help of remote sensing techniques validated by morphometric and geomorphological investigations.           

Doda has emerged as one of the most eco-fragile areas in J&K due to its unique geo-climatic conditions. It is prone to earthquakes and witnesses frequent low intensity quakes.

The vulnerability of geologically young unstable and fragile rocks in Doda have increased manifold due to various unscientific developmental activities.

A few months ago, big cracks in several houses in the mountainous Nai Basti area of Thathri in Doda district created panic among the residents. Seepage of rain water and haphazard construction of developmental projects has exacerbated the situation coupled with high tectonic activity. 

Experts state that the situation is aggravating from the Mohimangat-Shopian axis across Pir Panjal and Sumcham Padder, Padam Zanskar besides the main axis of Doda-Kulgam periphery. Uri, Bijhoma and Aharbal are on the earthquake fault lines. Chenab Valley housing huge dams on Chenab including Dul Hasti in Kishtwar, Baglihar in Ramban, is vulnerable to quakes. 

As per Bilham, a magnitude nine earthquake is likely to trigger landslides that would dam the Jhelum river, which drains from the Kashmir valley into Pakistan. This could put the Kashmir valley under water within three months. Bilham’s Global Positioning System (GPS) data readings reveal the gradual movement of rocks in the Zanskar Mountains north of the Kashmir Valley are high.

This means that the zone is likely to rupture when a quake eventually happens; could be nearly 200-kilometres wide. The zone would encompass the Kashmir Valley including the city of Srinagar, home to 1.5 million people.

Bilham states that if slippage occurs over a length of 300 kilometres, as is possible, a mega-quake of magnitude nine is the likely result. ‘Given building codes and population in the region that “could mean a death toll of 300,000 people,” Bilham warns.

Geological instabilities in Japan, situated on converging tectonic plates, caused over 1,000 tremors on an average each year. On March 11, 2011, a magnitude 9.1 earthquake struck off the northeast coast of Honshu on the Japan Trench.

Subsequent tsunami that was created by the powerful jolt hit the coast within 30 minutes— overflowing seawalls and disabling three nuclear reactors.

The devastating  2011 Tohoku Earthquake and Tsunami, often referred to as the Great East Japan earthquake and tsunami, resulted in over 18,000 dead, including several thousand victims who were never recovered besides rendering 450,000 homeless. 

Learning hard lessons, Japan after extensive research devised new design and regulations to construct quake proof buildings. The high-rise buildings in major cities of Japan are designed in a way that these sway rather than shake during earthquakes.

Japan uses seismic isolation techniques in constructions comprising mechanism of bearings and sliders under building minimising responses to ground motion during earthquakes.

It also uses a Base isolation technique devised on the anti-seismic design strategy that reduces the effect of earthquake ground motion by uncoupling superstructure from the foundation.

Engineers in Japan design beams, pillars, and walls in such a way that to absorb intense ground shaking.

If an earthquake above a certain magnitude strikes, the bullet train will stop and nuclear and other plants will automatically go into temporary shutdown in Japan to prevent loss of lives.

Japan uses disaster prevention administrative radio systems to communicate evacuation information soon after earthquakes strikes. Japan is recognised as one of the most earthquake-prepared nations for its effective disaster prevention and mitigation measures.  J&K needs to follow the Japan model.  

As a good beginning, the J & K government has decided to strictly implement the Standard Operating Procedure (SOP) issued by the Centre stressing on mandatory disaster management plans, risk assessment and eco-fragility studies in development projects.

These SOPs are especially for construction of highways, roads and tunnels within 100 km of the International Border (IB) or the Line of Control (LoC). However, the need of the hour is to implement the SOP in the whole J&K to prevent natural disasters.  
 

We witnessed a devastating earthquake of 7.8 magnitude that rocked Turkey and Syria on February 6, leaving around 11,000 dead while hundreds of buildings collapsed. We need to learn lessons from such disasters. Though earthquakes cannot be predicted, measures can be taken to minimise damage.

Development of buildings and projects on unconsolidated materials, moraines, and narrow valleys in tectonically active zones must be discouraged. There is a need to ensure scientific execution of developmental projects and buildings in areas vulnerable to earthquakes in J&K.           

We need to understand that the extent of damage to buildings depends not only on the magnitude of the earthquake but also on the type of construction practice followed. It has been observed that most of the houses constructed on centuries-old Dhajji-Diwari system especially in Kashmir have survived earthquakes.

These houses, constructed with wood, bricks and mud mortar, are considered quake-resistant due to its flexibility. The foundation of these traditional houses is constructed with stones.

Then masonry walls are constructed with bricks bonded with mud mortar and wooden bands connect the structure with the floor. Wooden beams in ceilings tie the structure together.

A house constructed in Dhajji-Diwari design sways together during a quake giving its flexible design, unlike concrete constructions. There is a need to reintroduce the Dhajji-Diwari system with modern touch as J&K falls in a high seismic zone.           

J&K Government should undertake micro-seismic zoning and risk assessment to minimise damage in case of high magnitude quakes.

There is a need to organise awareness programmes and mock-drills in every village and locality in J&K to make people aware about earthquakes and importantly disaster response measures.

Engineers and architects need to be roped in to devise safe building constructions designs and codes. We need to remember that earthquakes cannot be predicted or avoided.

We can only take measures to minimise damage by being prepared psychologically with a comprehensive disaster response system for facing earthquakes scientifically.

The author is Executive Editor, Greater Kashmir

DISCLAIMER: The views and opinions expressed in this article are the personal opinions of the author.

The facts, analysis, assumptions and perspective appearing in the article do not reflect the views of GK.

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