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Nepal earthquake of 1883 :
This earthquake had occurred on 26 August 1883.
The epicenter of this event lies close to Khatmandu. The maximum intensity is
IX on MM scale?. The trend of the iso-seismal are following the main central
thrust zone. in Himalayas. Estimates of moment magnitude based reported intensities
indicate that the earthquake was 7.5= orM=7.9. This event affected around
1 million sq.km region of northern India, Nepal and Tibet and caused heavy landslides, rockfalls and distruction of 4600 dwellings.
It took around 500 human lives( source:Atlas of seismotectonis of India, 2000, GSI pub.). |
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Coimbatore earthquake of 1900 :
Historically important earthquake in South India is Combatore earthquake of 8 February 1900.
Basu(1964) had srudied this earthquake in detail. He had observed damages due to this earthquake
in an area of about 96,000sq.miles (i.e., 248639sq.kms). He drew the isoseismals and found maximum
intensity as VII on MM scale and its focal depth is 70km. From isoseismal observed to be two centres,
one at Coimbatore and another near Salem. Basu had pointed out that the orientaion or trend of the
isoseimsl lines may indicate the fault plane direction. He further, concluded that a fault striking north-
northwest on the western coast is responsible for the earthquake. He found difficult to give any explanation
for the existence of two areas bound by isoseismal VI. He suggested that the secon zone could be either
due to a secondary focus or due to the existence of particular weak strata. |
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Kangra earthquake of 1905 :
The Kangra earthquake occurred in Himalchal Pradesh on 14 April 1905 and having a magnitude M8.6.
The maximum intensity of X on MM scale was covered an area of about 2000 Sq.miles (i.e., 5180sq.km)
and total affected area is about1,900.000 Sq.miles( 4920977 sq.km)
Middlemiss studied this earthquake in detail. Lives lost about 20,000 in Kangra earthquake of 1905.
He computed the focal depth of earthquake is 21-40 miles( 33.8-64km)
He concluded that the elongated epicentral tract is enclosed within three higher isoseismals. It was observed by him
that the isoseismal lines were closer towards west-north-west indicating a rapid attenuation in that direction rather
than wide spread lines in east-south-east direction. Kaila and Sarkar also have studied this earthquake to identidify
its nature of attenuations different directions such as West, Southwest (same gradients) and South,(same gradient)Southeast. They found the
same results as mentioned by Middlemiss earlier.
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Calcatta (now Kolkatta) Earthquakes of 1906 : The Middlemiss (1907)
had studies this calcutta earthquake of 19 September 1906.He had observed the maximum shake
land area of about 50,000 sq.miles(1,29,499sq.kms) ofBengal region.The maximum Intensity reported
at the epicenter was found to VI on MM scale as shown in the side figure. the epicentral area was
elongated north-south and coincided roughly withe course of Bhagirathi river down to its junction with
Hoogly river. About this earthquake was also studied by Kaila and Sarkar (1978) and identified more
rapidity in intensities in ver short distances. |
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Baluchistan earthquake of 1909 :
Heran (1912) had studied on 21 October 1909 Baluchistan earthquake in Kachhi plain, a bay of alluvium
enclosed on three sides by great flexure of ranges between Bagti and Kirthar hills.
The elongated isoseismals reached an Intensity value of IX on MM (Rossi-Forel =X) scale which is
shown in the side figure.
Kaila and Sarkar (1978) also studied about this earthquake
in their research work. 76 aftershocks noticed from the 21 to the 31October and again
14 shocks in November 1to 14, 1909. As shown in the map, isoseismals are an alongated oval,
in area about 450 sq.miles ( 1165 sq.km) with its longer axis running in N.W.-S.E direction it embraces
the two villages of Bag and Shahpur, the railway station of Bellpat and several small villages.
Heran further identified the geological in relation to the earthquake, Assuming that the epicentrum
is straight line, the trace of a fault running medially along the area of maximum disturbance
in this case is, parallel to the axes of folding. |
Baluchistan Earthquakes of 1931. The recently issued
part of the Memoirs of the Geological Survey of India (67, 1-82; 1934) contains an interesting study
by Mr. W. D. West on the destructive Baluchistan Earthquakes of August 25 and 27, 1931. The district
is one that is frequently visited by earthquakes, the most important predecessors being those of December
20, 1892, and October 31, 1909. Of the. two recent earthquakes, the earlier and less intense, known as
the Sharigh earthquake, occurred at about 3.5 a.m.,
I.S.T. (August 24, 9.35 p.m., G.M.T.). The epicentre was close to Sharigh and its focus was clearly shallow,
for, though the intensity was 8 (Rossi.Forel scale) in the epicentral area, it faded away rapidly, so that
the total area disturbed was only about 31,000 sq. miles. The second, or Mach, earthquake occurred
on August 27 at about 8.571/2 p.m., I.S.T. The epicentral tract was a long, narrow, curved band, follow-
ing closely t,be strike of the rocks for about 100 miles in a general southerly direccion from Mach. Within
this band, the shock reached the intensity X, and caused much destruction to buildings. The disturbed
area covered a large part pf Baluchistan and Sind and contained about 370,000 sq. miles, or about the
same as that of the Califonian earthquake of 1906. The epicentres of both earthquakes were closely
related to the re-entrant angle in the eastem boundary of the Baluchistan Hills, that of the Sharigh earth-
quake being on the northern side, and that of the Mach earthquake running parallel to the south-
westem side, of this angle.
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Srimangal earthquake of 1918 :
Srimangal earthquake rocked on 8 July 1918 in Bangladesh( now) and
having the magnitude of M7.6 on Rictcher scale. Staurt(1920) has given the iso-seismal map
prepared based on field investigations. The maximum epicentral intensity is X on MM scale. It had
covered Balisera valley and part of Doloi valley. The iso- seismal were found to be
regular having an apex towards north -west. The depth of focus estimated by
Staurt is about 8-9 miles(12-15 km). The shock was felt an area of 800,000 sq.miles (2,071,990sq.km).
Many tea estates were ruined. No caulalties reported. According to Kaila and Sarkar (1978), the
intensities attenuated rapidly within the short distance from the epicenter which indicates that the region
has marshy land of unconsolidated material and highly crushed crustal material. |
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Northwest Himalayan earthquake of 1929 :
Mukherjee (1950) had studied abiut this earthquake which had occuured on 1 Feabraury 1929 in
northwest Himalayan region. Its maximum intensity is IX on MM scale and magnitude is M7.1
with the focal depth of this event is about 200-250. This shock felt over an area from Delhi to
Uzbek- Turkistan,Tashkent and Hindhukush regions. This region is frequently visited number
significant earthquakes also. |
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Dhubri earthquake of 1930 :
After a period of relative quiescence lasting almost 12 years, a large portion of NE-India rocked the
Dhubri earthquake of 3 July 1930, affected by a renewal seismic activity, Centering near the
north-western end of Garo hills and adjoing valley of the Brahmaputra river,
this earthquake was felt a wide area from Calcutta-Sikkim, Manipur-Patna.
attended with disastrous results in northern Bengal and in western Assam,
and was felt It was studied in detai by Gee (1934).The magnitude of this earthquake was M7.1.
He is the first person to circulate questionaire to the observers in affected areas.
The maximum intensity observed was of the order of IX on MM scale.
The affected area of this disastrous earthquake was about 322,000 sq.miles (833976 sq.km).
The intensity of the shock was not felt in Tibet because of rapid decrease in intensity across Himalyas.
According to Kaila and Sarkar (1978), the attenuation (gradients) of these isoseismal are rapid
comparable with Assam earthquake of 1950. |
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Bihar-Nepal Earthquakes of 1934 :
The most catastrphic earthquake that shook the the northern Inadin belt before
pre- independence of India. This earthquake was studied by the officers of GSI(1939)
in detail. They identified some of the important factors as follows: The Bihar-Nepal
earthquake occurred on 15 January 1934, having a magnitude M8.4 and the maximum
Itensity of X on MM scale. Banerji (1935) had identified inequality of propagation of surface
vibrations in different directions. He also pointed out that the mountain folds and fault planes
which bound them should obstruct the normal propagation of surface waves.
In general, the intensity of the shock was found attenuate rapidly distance from the
epicenter lying on the eastern edge of the region covered by isoseismal X and its
maximum serious damages cuased by this event is 36,000 Sq.miles ( 93239 sq.km).
The high intensity region of the Nepal valley was attributed to the presence of
unconsolidated alluvium. Damage was great along river banks and low lying water-logged
areas bordereing the rivers. It was less on thick clay beds. Damage was also intense on
unstable hill slopes. The elliptical shape of the isoseismals was supposed to be due to
elongated nature of the focus and is situated 35 km away from the boundary fault. Kaila and Sarkar
(1978) had also highlighted about the trends of the isoseismal for the Bihar-Nepal earthquake in
their study as the isoseismal of IX to VI were found to be in close proximity to one another to the
aother to the north-west, east and southeast of the area affected by the earthquakeNorth of the Ganges the
pronounced indentations and close similarityof the curves IX and VI. The gradient of
this earthquake from the isseismal lines almost similar to Assam 1897.The shock was
felt an area of about(1900,000 sq.miles)) 4920977 Sq.km. Depth of focus reported by Roy (1939) from
seismometric study as 14.8 km. But Richter estimated as 20-30km. depth.
Banerji (1935) reported the focal depth 20km. |
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Quetta earthquake of 1935 :
W.D. west (1935) studied in detail on 31 May 1935 and its focal depth is 5 miles (8 km).
Davision (1936) had observed a line of fissuring in the ground was traced with occasional interruptions,
from the south side of Chiltan to neighbourhood of Kalat. Fissuring did not affect the solid rock
raher than alluvium As in many great earthquake, the shock
came with but slight warning from fore-shock in the central area, moderate intensity felt at
Kalat on April 25 and 4 other at Bostan(near Quetta). Number of aftershocks also occurred.
The epicentral area of about 1080sq.miles( 2797sq.km) The maximum intensity in Rossi-Forel
is X (XI on MM scale) covered an area of 105,000sq.miles (271949 sq.km). The intensity of the
shock attenuated rapidly from the epicentral region. |
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Hindhukush earthquake of 1937 :
Coulson(1938) had studied this earthquake of 14 November 1937 in detail by considering news paper reports as well
as meterological observation on damages. The shape of isoseismal lines are indicate that the
epicentral region was not very much large and that it is possible that the maximum
itensity of the shock above the focus did not exceed X on MM scale.
At some places like Gilgit an aeroplane sound. The magnitude of this earthquake was
about M7.2 and focal depthof about 200-240km. and it is also by number of Foreshock and
aftershocks were observed by him. |
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Satpura earthquake of 1938 :
Mukherjee (1942) had studied on Satpura earthquake 14 March, 1938 on the limb of mega
geo-fracture zone in central indian Normada- son valley graben region. A moderate strenght
of this earthquake felt over central India , Delhihi in the north and Begaum in the south,
on the east and west , the limits of the felt area do not have extended much beyond Seoni
and Bhavanagar, respectively.an unusually large area of about400,000 sq. miles(1035995 sq.km)
The maximum intensity at epicenter reached to VIII on MM scale and its focal depth is 40km.
The magnitude of the shock was M5.5 on richter scale.Due to this earthquake 100years old
Chopda hot spring was disappeared.The iso-seismals are oriented in north-south direction
roughly elliptical in shape.The decrease of intensity away from the earthquake epicenter
is not a rapid as it should be in shallow earthquake. |
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Great Pamir earthquake of 1939 :
Coulson (1940) had studied about this great pamir earthquake. He drew the iso-seismal based
on the field investigation in the north- west Himalayan regions. The maximum intensity is VIII on MM scale.
The shock felt over an area from Lahore to Kabul in Northwest direction and Srinagar in north and further
north as shown in the side figure. Mukherjee (1950) also studied this earthquake and drew the iso-seismal
which are different from the coulson's. The foacal depth may be about 200 km. Kaila and Sarkar (1978) have
compared the intensity attenuation from the observed iso-seismals found that the this earthquake had a
similar grdients with those of Hindikush and NW Himalayan earthqukes. |
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Chamba earthquake of 1945 :
The Chamba eartquake had occurred on 22 June 1945. It had caused considerable
damage to proprty. The maximum intensity is about IX on MM scale. The iso-seismal elongated in north-south direction. |
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Assam Earthquakes of 1950 :
The earthquake of 15 August 1950, is one the catastrophic events occurred after free India.
This earthquake was studied by several authors and is available in a Central Board of Geophysics as " Compilation of papers on Assam earthquake ".
This was felt over 1,130,000 sq.miles ( i.e. 29,266687 sq.km) (Tandon, 1953). The magnitude of the shock was 8.7. Poddar (1953) reported a
maximum focal depth of 30miles (48.28km). Ray (1953) said that the maximum Intensity is about XIIMM Scale.
The iso-seismal have been observed to be highly distorted because loose soil of Brahmaputra river belt area and hard sediments.
as shown in the side figure. Poddar ( 1950) has given the Isoseismal map based on GSI field damages. These isoseismalines are also indicating the orientation of the fault concealed in the map in the direction Southwest -Northeast direction as causative fault. |
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Anjar Earthquakes of 1956 :
In the Kutch region an earthquake of magnitude 7.0 had occurred on July 21, 1956 near Anjar town.The maximu intensity was IX at few places.
The Northeast - Southwest elliptical direction iso-seismals were drawn by Tandon (1959) after field observations of different damages.
The depth focus is 13-18 km.Tandon had observed that the damage to the easter portion is Anjar town was more severe than to the
western part. He attributed this to the fact that the eastern part of the town was built on soft ground whereas the western part was on hard trap rocks.
Kaila and Sarkar have also illustrated the this region had background historically heavy damges due to 1819 earthquake and Indus delta
in Samji town was rased to by 30,000 houses due to an earhquake of May 1668. |
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Delhi Earthquakes of 1960 :
Mukti Nath et al (1979) studied the Delhi earthquake of 27 August 1960.The maximum intensity of about VII on MM scale having magnitude of M6.0.
The elliptical isoseismal lines of the Delhi earthquake is indicating the north-east southwest feature paralell to the juction of Alwars and alluvium.
As the iso-seismals are more closely spaced on the western part than the eastern part.
The eastern part of the Delhi might be having weak zones The focal depth is about 40km based relaion of Gutenberg and Richter(1956) and ISC
had reported as 58km. as dedetailed by Kaila and Sarkar(1978). |
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Calcatta ( now Kolkatta) Earthquakes of 1964 : Jingran et al, (1969)
have studied an earthquake that shook the mouth of the Ganges inthe year 15 April 1964 having
a magnitude of M5.5 (ISC) The shock was felt an area of about 67,000sq.km and maximum Intensity
was VII. Worst affected areas were mainlt those flanking the Hugly river course. Kaila and Sarkar
(1978) mentioned this area was affected by two more significant earthquakes of 11 October 1737
and 29 September 1906. |
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Broach earthquake of 1970 :
The Broach earthquake of 23 March 1970 having the magnitude M6.0 (IMD) and USCGS) 5.8 Choudhury et al ((1970) reported the focal depth of 15-20km wheras USCGS determined as 3km for the same earthquake.
The isoseismal map drawn is showing maximum intensityof VII on MM scale.
The isoseismals were elongated appximately in the east-west direction.
Gupta et al (1972) had reported the Broach city is divided into two parts based the damages observed by them.
The more damges suffered in the elevated part than the low lying areas. According to Kaila and Sarkar (1997) had identified that the intensities attenuated rapidly for this region of Broach comparable with Calcatta earthquake of 1964. |
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Desamangalam Earthquakes :
This Earthquake was occured in 1956 in Anjar. |
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Dindigal earthquake :
This Earthquake was occured in 1956 in Anjar. |
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Bhadrachalam earthquake of 1969 :
Bhadrachalam earthquake of 13 April 1969 had occurred on Godavari Graben in
Peninsular India. The mangnitude of this event is M5.7(USCGS).
This earthquake felt an area of about 907,000sq.km.
Mukherji (1971) who determined the magnitude as M6.5 and the depth
of focus is 40km. The drawn by him are showing elliptical in nature.
Their maximum intensity VII+ on MM scale and its major axis tren is
almost in the east-west direction.
The causative fault may also be in that direction approximately.
This earthquake shook the ground upto four extreme places like
Nellore in the east, Poona in the west, Puri in the north and
salem-Coimbatore in the south.
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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Kinnaur earthquake of 1975 :
Singh et al (1977) have studied the most recent destructive earthquake of India of 19 Jaunuary
1975 which is known as Kinnaur earthquake. Most damage occurred at an altitude more than
3000 meters above sea level Land slide, rock falling and snow avalache occurred during this earthquake.
The magnitude estimated is M6.8 and its maximum intensity is IX on MM scale. The iso-seismals are
oriented north-south direction, whis is paralell to a fault Kaurik-Chango fault. Gosava et al (1977)
reported a focal depth of 30 km for this shock. The shock was felt over an area of of about 550sq.km radius.
Further, they stated that the isoseismals are elliptical in nature coinsiding with fold axis of the Himalayan belt
just like Kangra earthquake of 1905. Kaila and Sarkar (1978) have pointed out that the intensity attenuation
is rapid in short distance from the epicenter of this earthquake. Thus, the intensity gradients of both Kangra
and Kinnaur earhquakes in the west direction is same. From this, we infer that the intensity attenuation depends
upon the local geological conditions and their amplification due to mltiple seismic wave reflections within the
different strats of sediments in folded belts Himalayas.
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Koyna earthquake of 1967 :
The occurrence Koyna earthquake in Indian penisular shield have opened up a new vista of knowledge in seismological
studies in India by long jump in development of earth sciences in India. The Koyna earthquake had occuurred on
10 december 1967. Chatterji et al (1969) have given the iso-seismal map prepared from the field
investigations carried out by GSI, Central Water and Power Research Center(CWPRS) has given an
iso-seismal map. The maximum intensity is IX It was felt over an area of 697,600 sq.miles(Mukerjee,1971).
Its magnitude is M6.2. and focal depth 10km. The north-northwest orientation of elliptical shaped iso-seismals are along direction of
shears or multi-fractured zone of Koyna valley. Kaila and Sarkar (1978) have determined the intensity attenuation gradient very
much rapid within very very short distance of 25km radius for this Even today along this line about one lakh earthquakes have been occuring since
from the date of this earthquake. It is even misterious to scientists to know processes in detail. Hence,
we can treat this as practical seismic zone study area to know about the nature of earthquakes occurrence in such a limited seismic zone as lab. |
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Koyna earthquake of 1973 :
Gosavi et al (1977) studied another earthquake at Koyna which accurred on 17 October 1973,
It was having a magnitude of M5.2 and maximum itensity VI. It was felt an area of 150 sq.km
radius and had a focal depth of 10km. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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This Earthquake was occured in 1956 in Anjar. |
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Shimoga earthquake of 1975 :
Shimoga earthquake of 12 May 1975 is interesting as there are no historic events this region
except mining rock bursts. The shock had magnitude M5.0 and maximum intensity V, as reported
by Gosavi et al (1977). The iso-seismals were found to be crescent shaped with the concave side
facing north-northest. Focal depth and felt radius reported by them were 35 km and 140 km respectively.
Kaila and Sarkar(1978) also discussed in their studies on seismic zones for the Indian regions.
The shock was felt upto Mangalore in the south and upto Panjim in the north. |
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Utterakasi earthquake of 1991 :
This Earthquake was occured in 1956 in Anjar. |
| Killari earthquake of 1993 :
This Earthquake was occured in 1956 in Anjar. |
