Himalayan Earthquakes
The Chamoli district of Uttar Pradesh
witnessed an earthquake of magnitude 6.8 on Richter Scale in the early hours of 29th March, 1999 at 00 hours 35 minutes (IST), Causing extensive damage to property and loss of 103 lives. The effects of the earthquake were seen in six districts of Uttar Pradesh viz; Chamoli, Rudraprayag, Tehri Garhwal, Bageshwar, Uttarkashi and Pauri Garhwal. The impact of the earthquake was comparatively more severe in the districts of Chamoli and Rudraprayag.
Parameters
Date: 29.03.1999
Origin Time: 00hrs: 35 min: 13.4sec (IST)
Epicenter: 30.41 N 79.42 E
Focal Depth: 21Km
Magnitude: 6.8
An earthquake of magnitude 6.6 shook the districts of Uttarkashi, Tehri, and Chamoli in the state of Uttar Pradesh n October 20, 1991 at 2:52 hours. The death toll was estimated to be around 768 persons, with about 5,066 injured. The area has one of the lowest population density in the state, and hence the rather low number of deaths and injuries. The maximum intensity of IX on the MM scale was assigned to an area of about 20 square km. This earthquake provided excellent ground motion records (acceleration versus time history) in the area. Maximum
peak ground acceleration of about 0.31g was recorded at Uttarkashi. Ground motion records showed that in the Himalayan region, the motion has significantly higher amount of high-frequency contents. During the earthquake, collapse of houses with R.C. roof slab supported on weak random-rubble stone masonry clearly demonstrated the disastrous results of often neglected walls and columns vis-à-vis slabs and beams. Several 4-storey buildings in Uttarkashi (not designed or detailed by engineers) with R.C. frame and stone infills sustained the earthquake rather well! This was due to the presence of significant number of infills from foundation to the top of the building which acted as shear walls. From such examples, one could easily and incorrectly get carried away to conclude that all R.C. buildings in general are good for earthquakes. To sober one down, top two storeys of the 3-storey State Bank of India R.C. frame building collapsed . clearly illustrating the disaster that R.C. buildings can cause if not done right. An important bridge on the strategically important Uttarkashi-Harsil route collapsed; causing disruption of traffic for several days.
This magnitude 6.6 earthquake shook northern Bihar and Nepal on August 21, 1988 at 04:39 hours.
About 1004 persons died (282 in India and 722 in Nepal) and more than 16,000 injured; casualties were significantly reduced since in the summer time most people sleep outdoors. Significant damage was caused in three distinct regions: the area near the epicenter, and the areas around Munger (India) and Bhaktapur (near Kathmandu in Nepal); this damage pattern due to peculiar geology of the area is exactly similar to that of the 1934 Bihar-Nepal earthquake.
This 8.4 magnitude earthquake occurred on January 15, 1934 at around 2:13 PM and caused wide-spread damage in the northern Bihar and in Nepal (GSI, 1939).
The number of deaths was relatively low: about 7,253 in India and 3,400 in Nepal since most people are outdoors in the winter afternoon. Serious damage was caused in an area of about 300 km mean radius. The earthquake caused a maximum intensity of X in 125 km long and 30 km wide area. Besides, two distant areas both located about 160 km from the main damage area suffered intensity of X; these were Kathmandu valley in the north and Munger in the south; this happened due to peculiar geology of that region (e.g., Richter, 1958). Most buildings tilted and slumped bodily into the ground in an area of about 300 km long and of irregular width (sometimes exceeding 65 km); this area was termed as the "slump belt". The area of slump belt underwent extensive liquefaction. At places, six feet high embankments became level with the surrounding area. On the other hand, the depth of lakes, ponds, borrow areas, and other depressions became lower. The area of slump belt was associated with fissuring and emission of sand and water caused by liquefaction and formation of sand boils. One of the fissure was 15' deep, 30' wide, 900' long.
Kangra (Himachal Pradesh), India, Mw 7.8
Date : 4th April 1905
Epicentre: 3.9 kilometers south of Pathyar (Himachal Pradesh), India
Latitude: 32.10o N (2)
Longitude: 76.40o E (2)
Origin Time:00:49:48 UTC / 06:19:48 IST (2)
Magnitude: Mw 7.8 (2), Ms 7.8 (1)
Moment:7.86*10*20 Nm (2)
The earthquake that struck the Dharamshala-Kangra area in Himachal Pradesh on April 4th, 1905 is among the deadliest earthquakes in the history of India. According to the then provincial government of Punjab, 19,727 people were killed (7, 8). Many of the fatalities were from Dharamshala, Kangra and neighbouring towns and villages.
This earthquake was centred 3.9 kms south of Pathyar (Himachal Pradesh), India,
Or 12.7 kms E of Kangra (Himachal Pradesh), India,
Or 14.9 kilometres NNW of Dharamshala (Himachal Pradesh), India,
Or 57.2kilometres SSE of Chamba (Himachal Pradesh), India,
Or 73.6 kilometres E of Pathankot (Punjab), India,
Or 156 kilometres NNW of Chandigarh, India,
Or 203 kilometres ENE of Lahore (Punjab), Pakistan,
Or 392 kilometres NNW of New Delhi (N.C.T.), India
The shock hit at 6:19 am I.S.T. on April 4th, 1905 and is thought to have lasted at least 2 minutes. The worst damage was at Kangra (4). All the buildings were destroyed including the Golden Temple, the Municipal Dispensary, the Thana and the Treasury buildings. Only the golden cupola of the Golden Temple remained resting on the debris of the destroyed structure below. The Devi Temple and the Mission Church which lay side by side were both demolished, their wreckage mingling with each other. The intense ground shaking can be gauged from the fact that two ladies, a Mrs. Decauble and a Ms. Lorbeer who were sitting on a verandah of the Mission House, and killed as they were unable to escape. At the Sessions House ridge, branches were broken off Pepal and Banyan trees, and fissures ran across the earth. Kangra Fort was also ruined. Many landslides precipitated off the hill slopes in and around Kangra.
After Kangra, the hardest hit (4) were the towns of Dharamshala and Palampur. At Dharamshala, the motion was so strong that people were thrown to the ground as they
tried to run outdoors. The European Barracks that were occupied by the 7th Gurkha Rifles from Kohima at the time, was completely wrecked. 272 soldiers were killed here and 363 were injured. Many buildings in the vicinity such as the Armoury were badly damaged. Some buildings however, namely the Magazine, the Treasury and the Sadr Kanungo's office and record room were untouched. A tombstone at the cemetery was found to have been twisted around by the earthquake. Many buildings were also destroyed on Dharamshala Civil Hill. McLeodganj Bazaar and Kotwali Bazaar were levelled to the ground. At the Jail house site, there were numerous fissures and at one location, there was a slump of 10 feet along an old fracture. The number of casualties was very high. Much of the deaths can be attributed to the severe shaking and the timing of the quake, when most people were indoors. Another major factor was that most of the government officials were killed and there was no one to help in or to supervise rescue and relief. It it believed that voices could be heard for many days from beneath the rubble crying out for help.
About 100 persons were feared dead at Palampur. Many buildings in the town, like the court house, church, school and sessions house were destroyed with a few sections of wall left standing. Some building however, escaped and like the Post Office were still in use after the quake. In the mountainous regions surrounding Kangra and Dharamshala, there were several major landslides, rockfalls and avalanches. Some rockfalls were so massive, such as the one at Barwar, that they created new lakes. At some other locations rockfalls resulted in several horrific deaths, when entire houses were crushed by a single fallen slab of rock. This was the case at a village near Mandi, where an entire family was killed when a massive rock fell onto their home.
Away
from the hills, and in the plains of the Punjab (4) in northern India (and now also northern Pakistan), there was slight to considerable damage. Sand vents and earthquake fountains were reported from near Bijnor, Khanki, Haridwar and Roorkee. Buildings were seriously damaged and some even partially collapsed at many major cities in the region, such as Amritsar, Lahore, Jullunder, Sialkot, Jammu, Rawalpindi and Amballa. The Lahore Town hall was damaged and so was the Lahore Railway station and Mayo hospital. Several British administrators and missionaries were killed or injured. At Shimla (6), Lady Curzon, wife of the Viceroy Lord Curzon, had a close escape from death when a chimney crashed into the room in which she was sleeping. Strong tremors, strong enough to cause light damage were also experienced at New Delhi, Gurjanwala, Poonch and Rohtak to name a few. Light to moderate tremors rumbled across the sub-continent, and were felt as far as Ahmedabad, Surat, Quetta, Jalalabad (Afghanistan), Lucknow and at many locations in present day Bangladesh. Water oscillations (4) were reported from many locations in the Bengal and Myanmar. Initially it was believed that there had been some ground level changes (5) in the region between Dehra Dun and Mussourie, however, it is now known that there were probably serious errors in the readings taken at the time (1). Recent studies indicate that this earthquake had Ms magnitude of 7.8 (1), unlike previously inflated values as high as 8.6 (3). The moment magnitude has also been reassessed and has been found to be 7.8 (2, 9). It has also been pointed out (1) that the low intensity area between two locations of high intensity, i.e. Kangra area and the Dehradun area, was as a result of an improper survey in the area, as it was sparsely populated and had few structures that might have been affected.
There were hundreds of aftershocks (4) some of which were considerably strong and were even felt in the plains of northern India. The largest earthquake within a year of the main event on April 4th, 1905 was the magnitude (2) 6.4 Bashahr quake, which caused damage in the Kulu area and was felt as far as Jaipur. This was undoubtedly a serious earthquake in its own right, but was referred to as the Bashahr "aftershock".
