B.D. Mal Barna
The Times of India newspaper, on 18th of May 2016, published under heading U S scientists say major earthquake is likely in Jammu and Kashmir. The said Scientists have found that the Reasi fault near Jammu has been building up pressure for sometimes, suggesting that when it does release or slip, the resulting earthquake may be as large as of magnitude 8.0 or greater. Yann Gasvillot’s (A Doctorate student at Oregon State University), Conclusion is “that what we found was that Reasi fault is one of the main active faults in Kashmir but there is a lack of earthquakes in the more recent records. The fault has not slipped for a long time, which means the potential for a large earthquake is strong since there is no earthquake or movement along this Reasi thrust/fault for the last 4000 years”. This is too simplistic statement and is not the logical argument or reason for a major earthquakes. In case there is no release of pressure for 4000 years, then in other words, the fault might have become dormant or dead.
At the outset, I shall like to assure my Jammu and Kashmir people especially Jammu city people or people living along the Reasi-Katra thrust/fault that people should not worry unnecessarily over the hype of imminent devastating temblor due to Reasi-Katra Fault/Thrust or in other words Main Boundary Fault/Thrust displacement. Reasi-Katra Fault/Thrust is a segment of Main Boundary Fault/Thrust and I myself have been working on varied Engineering Geology Problems in different projects of national importance along this Tectonic Plane/Zone from the year 1977 to till date i.e. for the last 39 years. This 100m to 500m thick Reasi-Katra Fault/Thrust Zone or Main Boundary Fault/Thrust Zone is about 1500km in length extending from Pakistan to Nagaland and beyond. Besides working along the Reasi fault, between Reasi and Udhampur areas, I have examined the fault both sides of Ravi river and also in Arunachal Pradesh area. I have carried out detailed geological mapping of the Reasi fault between Reasi and Katra area and noticed many neotectonic activities along the Reasi fault which are indicative of periodic release of built-up stress in the recent times. Earlier my senior colleagues have also carried out geological mapping of the Reasi thrust with similar reports. My simple argument is that since many years we have been tunneling within this fault for rail line construction with accompanied blasting within the tunnels and adjoining areas then pressure so accumulated should have been released during blasting, causing devastation all around. No such thing happened.
I can only say that research scholars of OSUS College of Earth have created panic in the area with the help of local geology research scholars to get money from the Government to carry out their research work at many locations along the thrust/fault. Their conclusions are not based on hard ground geological data which is collected after hard labour on the site over years of field work.
As highlighted in the Daily Excelsior editorial also, till date there is no scientific technique available anywhere in the world to predict occurrence of earthquakes with reasonable degree of accuracy with regard to space, time and magnitude. It is thus suggested that one should not worry about the occurrence of earthquake when we don’t know the time, location and magnitude. We only need to be always prepared for such eventuality. Most of the area in J&K falls in Seismic Zone-IV of the Earthquake Zonation Map of India. So is Delhi which too enjoys this status of Zone-IV. Only some parts of Kashmir such as Baramulla have been demarcated in the highest Seismic Zone which is Zone-V.
After reading editorial of Daily Excelsior that the warning issued by the American experts has caused much concern to the Governor of the state and he has sent a communication to the Chief Minister for dealing fully with the threat of possible disaster caused by terrible earthquake as anticipated by American expert team. I may state that research scholars cannot be experts unless they work for many years at many difficult sites in the field involving intensive geological field work. Yann Gavillot, as reported, was doing his PhD work on Reasi fault. I do not doubt at Oregon State University, but research scholar cannot be expert while doing his research work. Our Indian students also go to America or in other countries for higher studies but they cannot become experts unless they work for many years at number of locations.
I wish to delve briefly on the background aspect of the Earthquake Hype. It appears that Yann Gavillot might have been misguided by some scholars of Geology Department of Jammu University with vested interests. To support this statement, I may inform that some days back i.e. before the printing of this news, there were some rumours within scholars that Chenab Bridge is being constructed over the thrust as such this bridge may fail.
Around about the year 2000, Jammu University professors published in Daily Excelsior that Baglihar Hydel Project is being constructed over Murree thrust and Dam will fail. Those professors were briefed about the project in one geology workshop held at Jammu about the design of the project. The same dam has been working smoothly till date.
After a couple of years, same team of professors wrote an article that a major earthquake will take place shortly and huge damage is anticipated in Jammu area. The undersigned also replied against this anticipated major earthquake through Daily Excelsior. Many years have passed but no earthquake has taken place. Subsequently, Jammu University Geology Department has installed a number of seismological stations at district level, funded by Department of Science & Technology (DST) and State Government.
The occurrence of earthquake in Himalayan region is attributed mainly to the tectonic features. Besides a number of local faults and reverse faults, four major thrust zones i.e. reverse faults viz. (1) Main Boundary Thrust, (2) Murree Thrust, (3)Punjal thrust, (4) Main Central Thrust traverse the J&K state and other states beyond J&K. From the available geological data and seismological evidences, it is seen that these faults have been found to be active in the past. According to the theory of plate tectonics, areas near the main boundary of Indian and Eurasian plates are subjected to deformation due to plate movements. Geophysical data in and around Himalayas have shown that Indian plate is moving in north-north-east direction at an average speed of 5 cm per year due to which tremendous amount of stress is accumulating in the region. The stress so accumulated is occasionally released through earthquakes and smaller magnitude tectonic activity in the region. The fact is further corroborated by the detailed seismological investigation carried out after installation of seismological observatories in Himachal Pradesh and J & K states for Beas and Salal Hydel Projects which reveal that there is well marked concentration of earthquakes in the grid 32° to 33° And 76° to 77° which is the region where great Kangra earthquake of 1905, the Chamba earthquake of 1945 and Bhaddu earthquake in 1980 occurred.
Bureau of Indian Standards [IS-1893 (part-I:2002)] based on various scientific inputs from a number of agencies, has grouped the country into four seismic zones viz. Zone –II, Zone-III, Zone-IV and Zone-V. Of these, Zone-V is the most seismically active region while Zone-II in the least. In the seismic Zoning Map of India, except some portion around Srinagar city which falls under zone-V, the entire Jammu, Kashmir and Ladakh region falls under Zone-IV. However, design engineers (CWC and others) prepare the designs of all dams, bridges and tunnels in J&K state area under the highest seismic Zone –V which act as great safety measure.
To prepare the design of Udhampur-Srinagar-Baramulla railway project, seismological data collected by Indian Meteorological Department (IMD) between the periods of 1505 to July 2002 was collated, the copy of which is available with the author. This data reveals that after Kangra earthquake in 1905, 99% earthquake readings are between 2 and 4 magnitude and only few readings are around 5 magnitudes on Richter scale.
To study the seismic activities along the Reasi thrust and other thrusts in the area, three seismological observatory stations at Jyotipuram, Ramban and Jammu, were installed by IMD. After July 2002 when there was no enhancement in the seismic readings, these three seismic observatories were closed. This scientific data collected over years further indicates that there is no increase in stress along Reasi fault and other thrusts in the area.
(The author is Retired Director of Engineering Geology Wing of Geological Survey of India)
feedbackexcelsior@gmail.com
Follow our WhatsApp channel