— Death toll in Nepal has reached over 2200. In India, it is around 60. In countries other than Nepal, the figure is around 80.

— Nepal had another aftershock today – of 6.7 according to the USGS – the tremors of which were felt in Nepal, many parts of India and Pakistan. It was a strong aftershock with epicentre 17 Kms South of Kodari and just 10 Kms deep. A tremor of magnitude 5 was also felt after it.

— Yesterday and today, Nepal has continued to feel the aftershocks. The whole of the Kathmandu valley is badly devastated. Social media is inundated with ‘before and after’ photographs. Many heritage buildings are lost, completely decimated to the ground. The quake has brought down entire localities and villages.

— India was the first country that sent its crew for rescue and relief work. C-130J and C-17 choppers reached with relief material, experts, officials and National Disaster Response Force personnel yesterday. Mi-17 helicopters were thrust into the operation as well.

— Indian Prime Minister is holding an emergency meeting at 3:30 PM after the strong aftershock today.

— The death toll in Mount Everest area, on and around its base camp, is around 20 and is expected to go with quake-induced avalanches.

— Nepal is epicentre of destruction. Maximum reports are available from Kathmandu and Kathmandu valley while, with the passing time, reports from other of quake-affected districts of Nepal will also be made available. Right now, the power and water lines are down and not working for most of the affected areas. Communication lines including the internet are also badly hit.

— The death-toll is expected to be in tens of thousands. The US Geological Survey has designated the danger level associated with Saturday’s earthquake as red meaning it is expecting ‘high casualties and extensive damage and the disaster is likely widespread.

— Nepal’s population is around 28 million and a major part of it is badly affected. According to the United Nations, in all, some 6.6 million people in Nepal are badly affected by Saturday’s earthquake and need national and international response. People are staying outdoors. Houses remain empty with mass-scale damage to houses and buildings and continued aftershocks.

— Nepal is an impoverished country. Tourism is one of the major factors pushing up the economy. Earth’s highest point, Mount Everest, is in Nepal and this, along with the Himalayan range, is hot trekking spot for tourists across the globe, earning the much required tourism money.

— Due to the quake, around 300,000 foreign tourists are trapped in Nepal.

— India, while helping the country with rescue and relief work and working on the reconnaissance missions, is also evacuating its people stranded there.

— Given the massive nature of earthquake and the destruction in its aftermath, help from various countries is reaching in Nepal, especially from its neighbours, India, China and Pakistan. They are trying to help the landlocked nation as well as evacuating their people trapped there. They are there with food items, equipments to rescue the survivors and to find the dead bodies from under the rubble, medical teams to help people, officials to engage in rescue and relief work, experts in these circumstances, reconnaissance missions for Kathmandu valley and other quake affected areas of Nepal and so far.

— From India, for 72 hours, all calls to Nepal on the BSNL network will be local calls while the same will be free for 48 hours on Airtel network.

— Air India, IndiGo and SpiceJet have announced to carry free cargo to Nepal in the aftermath.

— A strong earthquake yesterday, around Noon, had hit Nepal badly, sending strong tremors in the neighbouring countries of India, China, Pakistan, Bhutan and Bangladesh. While North and Eastern India were strongly hit with Bihar facing the maximum damage in India, in Nepal, it caused massive destruction the scale of which was to realize in coming hours.

Related post:

©/IPR: Santosh Chaubey –



I was in the washroom when it happened. Around noon, the ground started shaking.

First, as a natural reaction (yes, it is also a type with some folks), I thought I was feeling dizziness and it was stirring my whole body, the ground beneath me and the walls surrounding.

But soon, within seconds, the feeling of dizziness gave way to the feeling that I was facing tremors of an earthquake.

And it was a strong earthquake, if it was indeed a quake. It lasted for around two minutes. It shook me and the world around me pretty well.

I was at the ground floor. There were three stories above me. And I was in two minds.

As I had slept very late, the whole ‘world beneath and around and with me’ business could have been due to some ‘psychological response’ due to my dizziness.

But then, it lasted for around two minutes and was like a strong earthquake (as I had felt in the past), the logic of my dizziness was hanging around the other logic as well.

I felt its epicentre was not at a place nearby otherwise the building would have come down like a stack of cards even before I would get a chance to contemplate over it. After all, Delhi is in Zone 4, ecologically the second most quake-prone zone. Yes, but it should be a strong one as it stirred my soul.

I was even ready to die in case the building came down, if indeed it was an earthquake. Any effort to rush out, from the ground-floor washroom of the four-stories building of IP Extension, was futile because it would not give me that much time.

The time that I indeed got – to contemplate over it – to think – that made my mind thought in two ways.

So, overall, as my visage said, I was in two minds. I was attributing it to my dizziness and at the same time, I was thinking about a strong earthquake.

I came out of the washroom following my daily routine – with thoughts on these lines.

I decided to ask my younger sister and the kids of my elder sister if they felt anything like an earthquake. They were busy here and there and flatly denied experiencing it at all, except what they were doing.

So, my dizziness had an upper hand.

But the next moment, when I glanced over the news channel running on television that I had switched on before going to the washroom, the whole dizziness logic was squeezed out of my soul.

The earthquake was confirmed, a strong earthquake. The news channel was running the news of an earthquake and its shocks.

And like it happens, in case of a strong earthquake, there was an excess of information with problems of credibility leading to a sort of chaos.

The magnitude ranged from 7 to 7.5 and soon the US Geological Survey confirmed it. Its epicentre was said to be in Nepal and soon, the USGS confirmed it, saying it to be 36 Kms East of Lamjung district that is just 77 Kms from Kathmandu.

Every news channel was on it. After Nepal, it was felt strongly in India, especially in North India, with Bihar and West Bengal facing the maximum damage. News channels were running the preliminary footage while scrambling for the same. Social media was beginning to act on it.

Meanwhile, there were frantic calls to and from everyone in the family about safety and whereabouts of each of us in the family.

The information that it was indeed a strong earthquake then opened a floodgate of horror before my eyes. If it was felt so strongly across many parts of the India, what would it do to Nepal, a small impoverished Himalayan nation that is dependent on tourism to a large extent with Mount Everest, the highest point on Earth, on its land?

©/IPR: Santosh Chaubey –


Twitter has a lot of them. Go and search for. Similar is the case for photographs. The social media is inundated with them.

YouTube has not many in terms of varying nature of visuals. All are Kathmandu centric and therefore visuals contain similar elements. Its destruction – the extent of damage is revealing itself every passing hour.

After Nepal, the country with the epicentre of the earthquake and therefore the subsequent damage, India is there, facing destruction in many parts, especially in Bihar and West Bengal.

YouTube has some videos by mainstream news carriers showing the scale of destruction in India. They have done so in addition to the situation in Nepal.

More reports are awaited and death-toll from Nepal will be many thousands.

Here are some of the YouTube links: – The Telegraph – Bangla TV –ANI – AP – NDTV – NDTV – BBC – CNN – ABP NEWS – AAJTAK – BBC – BBC – AAJTAK – HEADLINES TODAY


— According to the reports so far, around 800 have died in Nepal, around 35 in India, 6 in China and 2 in Bangladesh. More reports are awaited and figures are bound to go up.

— While writing this, the magnitude of the earthquake is found to be around 7.8 by the US Geological Survey. It began with 7.5, revised its estimates to 7.9 and then came down to 7.8. The origin’s depth was found to be 15 Kms.

— According to the local Nepali time, the earthquake shook the grounds at 11:56 AM (11:41 AM in India – according to India time that is 15 minutes behind Nepal). The second earthquake at 6:45 PM was 6.6 on the Richter-Scale. There were some 16 aftershocks reported so far.

— Epicentre of the quake is said to be 34 Kms East of Lamjung, a Nepali city that is predominantly agricultural in nature.

— From Kathmandu, the quake epicentre is just around 77 Kms away, in the North-West direction, according to the estimates of the US Geological Survey.

— The main event of the earthquake lasted for around 30 seconds to 2 minutes at different locations.

— Tremors were felt in many countries including India, Pakistan, Bangladesh and China. After Nepal, India is expected to be badly affected. North India and East India are reporting destruction with quake being felt as far as Mumbai and in parts of Andhra Pradesh.

— In Nepal, the death toll is expected to be in thousands. Earthquake destruction assessment takes time.

— Nepal is an impoverished country where power and communication lines are down in the quake aftermath.

— The death figure available so far is basically from Kathmandu and other some other cities. Many places are so remote, and with communication and power lines down, it will take time to assess the damage there.

— Kathmandu airport is shut and the flights to it are diverted to India. The whole city is a scene of destruction with many of its heritage sites lost in the earthquake.

— Nepal is in quake fault-line zone, and so are the quake-affected areas in all other countries in today’s earthquake. While Nepal is a tourism and agrarian economy, Kathmandu is cosmopolitan in nature and is densely inhabited. We have preliminary assessment of destruction from Kathmandu but the overall report will take time.

— It’s after 80 years that Nepal has faced such a massive earthquake. An earthquake of magnitude 8.2 had hit Nepal and Bihar in 1934 decimating Kathmandu, other parts of Nepal and parts of Bihar including Muzaffarpur and Munger.

— This time also, in India, Bihar is the worst affected Indian state, though it is expected to be unlike the last time. Many of its districts have reported quake damage, death toll and the assessment is on.

— Tourism is Nepal’s main source of income for a country of 27.8 million with Mount Everest and Himalayan trekking being the main sources. Also, many of Nepali temples including those in Kathmandu and Janakpur are holy places for Hinduism and Hindus flock to visit these temples.

— Indian Prime Minister Narendra Modi has spoken with Nepali President and Prime Minister. India is helping in rescue, relief and reconnaissance. One of the Indian aircrafts with a team of NDRF (National Disaster Response Force) personnel has landed there. Other Indian teams with more NDRF personnel and Indian experts are on their way.

— A quake triggered avalanche has caused widespread damage to the tourism related to the Himalaya and the Mount Everest. Some 8 Everest climbers have died so far, near the area of the base camp the reports say. More reports are awaited. And we have not forgotten the avalanche of April 2014 that had killed 16 Sherpas.

©/IPR: Santosh Chaubey –


Earthquake – M7.8 – 34km ESE of Lamjung, Nepal
28.147°N 84.708°E depth=15.0 km (9.3 mi)


USGS comes back to the earlier assessment. Nearby Cities:

  • 34km (21mi) ESE of Lamjung, Nepal
  • 58km (36mi) NNE of Bharatpur, Nepal
  • 73km (45mi) E of Pokhara, Nepal
  • 76km (47mi) NW of Kirtipur, Nepal
  • 77km (48mi) NW of Kathmandu, Nepal


  • 2015-04-25 06:11:26 (UTC)
  • 2015-04-25 11:56:26 – Nepal
  • 2015-04-25 11:41:26 (UTC+05:30) – India

(11:41 AM in India – according to India time that is 15 minutes behind Nepal)


M6.6 – 49km E of Lamjung, Nepal
28.193°N 84.865°E depth=14.6 km (9.1 mi)


  • 49km (30mi) E of Lamjung, Nepal
  • 69km (43mi) NW of Kirtipur, Nepal
  • 70km (43mi) NW of Kathmandu, Nepal
  • 70km (43mi) NE of Bharatpur, Nepal
  • 72km (45mi) NW of Patan, Nepal


  • 2015-04-25 06:45:21 (UTC)
  • 2015-04-25 – 12:30:21 – Nepal
  • 2015-04-25 12:15:21 (UTC+05:30) – India

Nepal Quake USGS

Source: US Geological Survey


M7.9 – 29km ESE of Lamjung, Nepal
Depth: 28.131°N 84.649°E depth=15.0 km (9.3 mi) ) (+/- 1.8 km)
Origin Time: 2015-04-25 06:11:26.160 UTC (11:56 AM Nepal time)


Intensity Map


Intensity Vs Distance Plot

The response to the US Geological Survey so far tells how wide the impact the earthquake is going to be.

Did You Feel It

Location MMI Responses Distance
Bharatpur, Chitwan Nepal IX 1 57
Bidur, Nuwakot Nepal II 1 58
Pokharā, Kaski Nepal VII 4 67
Kathmandu, Kathmandu Nepal IX 1 81
Lalitpur, Lalitpur Nepal VIII 2 84
Bansgaon, Uttar Pradesh India V 1 217
Chapra, Bihar India II 1 260
Khargupur, Uttar Pradesh India II 1 276
Patna, Bihar India VI 1 282
Phulwari, Bihar India IV 4 284
Fyzabad, Uttar Pradesh India V 1 290
Nanpara, Uttar Pradesh India III 1 311
Biratnagar, Morang Nepal VIII 1 319
Jarwal, Uttar Pradesh India IV 1 324
Banares, Uttar Pradesh India III 3 351
Banmankhi, Bihar India IV 1 354
Biswan, Uttar Pradesh India II 1 366
Gezing, Sikkim India III 1 369
Jais, Uttar Pradesh India II 1 373
Darjeeling, Bangla India II 1 376
Itaunja, Uttar Pradesh India IV 2 386
Lakhnau Cantonment, Uttar Pradesh India III 1 392
Lakhnau, Uttar Pradesh India IV 16 395
Kalimpong, Bangla India V 1 396
Rangpo, Sikkim India VI 1 397
Rae Bareli, Uttar Pradesh India II 1 399
Gangtok, Sikkim India IV 1 400
Dhangadhi, Kailali Nepal III 1 402
Jhūsi, Uttar Pradesh India V 1 403
Shilīguri, Bangla India VII 3 404
Colgong, Bihar India III 1 407
Allahābād, Uttar Pradesh India V 1 408
Allahābād Cantonment, Uttar Pradesh India III 1 410
Unao, Uttar Pradesh India IV 1 447
Kaliaganj, Bangla India IV 1 458
Cawnpore, Uttar Pradesh India IV 6 465
Sjahjahanpur, Uttar Pradesh India III 1 468
Kanpur, Uttar Pradesh India IV 7 468
English Bazar, Bangla India V 1 490
Thimphu, Thimphu Bhutan IV 7 503
Rura, Uttar Pradesh India IV 3 504
Kichha, Uttaranchal India II 1 511
Almora, Uttaranchal India III 2 513
Cooch Behar, Bangla India IV 1 516
Kanke, Jharkhand India II 1 525
Fatehganj Pashchimi, Uttar Pradesh India III 1 526
Ranchee, Jharkhand India V 2 533
Jiaganj Azimganj, Bangla India V 1 563
Khunti, Jharkhand India III 2 563
Orai, Uttar Pradesh India III 1 567
Rajshahi, Rājshāhī Bangladesh IV 2 573
Baharampur, Bangla India V 1 573
Durgapur, Bangla India IV 1 578
Bolpur, Bangla India IV 2 581
Amanpur, Uttar Pradesh India II 1 582
Moradabad, Uttar Pradesh India III 1 582
Naţor, Naţor Bangladesh IV 1 597
Navadwīp, Bangla India V 1 641
Memari, Bangla India II 1 648
Āgra, Uttar Pradesh India III 1 663
Āgra Cantonment, Uttar Pradesh India IV 1 663
Morar Cantonment, Madhya Pradesh India II 1 670
Gwalior, Madhya Pradesh India III 1 675
Tangail, Tangāyal Bangladesh II 1 680
Maimansingh, Maimansingh Bangladesh IV 1 684
Mīrat, Uttar Pradesh India III 1 686
Rūrkī, Uttaranchal India II 1 686
Dehra Dūn, Uttaranchal India II 1 686
Vrindaban, Uttar Pradesh India II 1 687
Pilkhuwa, Uttar Pradesh India V 1 689
Mīrat Cantonment, Uttar Pradesh India III 1 690
Naihati, Bangla India III 1 692
Bhadreswar, Bangla India III 1 694
Haringhata Dairyfarm, Bangla India III 1 696
Dadri, Uttar Pradesh India IV 3 697
Dankaur, Uttar Pradesh India V 2 697
Bali Chak, Bangla India III 1 702
Barakpur, Bangla India III 1 703
Frederiksnagar, Bangla India III 1 703
Habra, Bangla India III 1 709
Kolaghat, Bangla India IV 1 710
Ghaziabad, Uttar Pradesh India IV 5 712
Chakpara, Bangla India V 1 714
Rangia, Assam India IV 2 715
Bankra, Bangla India IV 2 716
Ula, Bangla India IV 1 717
Dum Dum, Bangla India III 3 717
Haora, Bangla India II 1 718
Noida, Uttar Pradesh India IV 11 719
South Dum Dum, Bangla India IV 3 719
Barabazar, Bangla India IV 9 720
Palwal, Haryana India IV 2 720
Calcutta, Bangla India IV 10 720
Faridabad, Haryana India IV 2 721
Bidhannagar, Bangla India IV 6 723
Gharonda, Delhi India IV 5 724
Jabalpur Cantonment, Madhya Pradesh India V 1 725
Babarpur, Delhi India III 1 725
Gokalpur, Delhi India IV 2 725
Dhamrai, Dhāka Bangladesh V 2 727
Chakdaha, Bangla India IV 4 728
Tigri, Delhi India III 5 729
Deoli, Delhi India IV 3 729
Ni Dilli, Delhi India IV 19 730
Delhi, Delhi India IV 15 731
Bhalswa Jahangirpur, Delhi India IV 3 735
Gauhati, Assam India IV 1 736
Dilli Cantonment, Delhi India III 6 736
Rajpur, Bangla India V 3 737
Alīpur, Delhi India II 1 738
Ţungī, Gazipur Bangladesh IV 32 743
Nangloi Jat, Delhi India III 10 745
Dohar, Dhāka Bangladesh IV 1 746
Dispur, Assam India IV 1 746
Gurgaon, Haryana India IV 23 750
Roshan Pura, Delhi India V 3 752
Sonīpat, Haryana India III 1 753
Dacca, Dhāka Bangladesh IV 26 756
Taoru, Haryana India II 1 756
Khulna, Khulnā Bangladesh III 1 766
Narayanganj, Nārāyanganj Bangladesh IV 1 770
Balasore, Orissa India IV 1 771
Shillong, Meghalaya India IV 2 771
Chatak, Sūnāmganj Bangladesh IV 1 778
Silhaţ, Silhaţ Bangladesh IV 2 803
Dera Bassi, Punjab India III 1 805
Angul, Orissa India III 1 807
Raha Gaon, Assam India III 1 808
Agartala, Tripura India IV 1 815
Raipur, Chhattisgarh India II 1 822
Ranirbazar NP, Tripura India III 1 824
Bahror, Rajasthan India IV 1 825
Kharar, Punjab India II 1 828
Kataka, Orissa India III 1 857
Bhubaneswar, Orissa India III 4 879
HisÄ?r, Haryana India IV 2 880
Jaipur, Rajasthan India IV 12 884
Itanagar, Arunachal Pradesh India V 1 891
Bhopal, Madhya Pradesh India IV 1 907
Puri, Orissa India III 2 929
Lachhmangarh, Rajasthan India III 1 947
Jorhat, Assam India III 1 956
Chattagam, Chāţţagām Bangladesh IV 1 966
Ganjam, Orissa India II 1 970
Barbari, Assam India II 1 1010
Visakhapatnam, Andhra Pradesh India III 2 1160
YÄ?rÄ?da, Andhra Pradesh India II 1 1169
Kahuta, Punjab Pakistan II 1 1236
Cocanada, Andhra Pradesh India II 1 1261
Rajahmundry, Andhra Pradesh India III 2 1265
Tadepalligudem, Andhra Pradesh India II 1 1293
Chandkheda, Gujarat India III 1 1329
Kadi, Gujarat India II 1 1331
Ahmadabad, Gujarat India III 8 1337
Ghatlodiya, Gujarat India III 1 1339
Memnagar, Gujarat India II 2 1341
Ranip, Gujarat India II 1 1341
Sarkhej, Gujarat India IV 1 1347
Sūrat, Gujarat India III 3 1422
Pune, Maharashtra India II 1 1533
Tannah, Maharashtra India IV 1 1548
Navi Mumbai, Maharashtra India III 1 1548
Madras, Tamil Nadu India II 1 1726
Bommanahalli, Karnataka India III 1 1827
Bangalore, Karnataka India IV 1 1834

Source: US Geological Survey


M7.9 – 29km ESE of Lamjung, Nepal
Depth: 28.131°N 84.649°E depth=15.0 km (9.3 mi)


Expected Economic Loss

Estimated Fatalities

Population per ~1 sq. km. from LandScan

Estimated Population Exposure


  • Overall, the population in this region resides in structures that are highly vulnerable to earthquake shaking, though some resistant structures exist. The predominant vulnerable building types are unreinforced brick masonry and rubble/field stone masonry construction.


  • Recent earthquakes in this area have caused secondary hazards such as landslides and liquefaction that might have contributed to losses.


MMI — City — Pop.
VII — Bharatpur — 107k
VII — Lamjung — <1k
VII — Khudi — <1k
VI — Kathmandu — 1,442k
VI — Ramnagar — 43k
VI — Hitura — 85k
VI — Pokhara — 200k
VI — Gorakhpur–  674k
V — Muzaffarpur — 333k
V — Patna — 1,600k
IV — Dhankuta — 22k
From GeoNames Database of Cities with 1,000 or more residents (k = x1,000)

MMI — Shaking — Pop.
I — Not Felt –*
II-III — Weak –*
IV — Light — 9,194k*
V — Moderate–  98,089k*
VI — Strong — 44,441k
VII — Very Strong —  1,801k
VIII — Severe — 14k
IX — Violent — 0k
X — Extreme —  0k
*Estimated exposure only includes population within map area (k = x1,000)

Source: US Geological Survey


M7.9 – 29km ESE of Lamjung, Nepal
Depth: 28.131°N 84.649°E depth=15.0 km (9.3 mi)

Data source: US

Nepal Quake USGS

USGS revises estimates to distance of nearby cities as well:

  • 29km (18mi) ESE of Lamjung, Nepal
  • 53km (33mi) NNE of Bharatpur, Nepal
  • 68km (42mi) ESE of Pokhara, Nepal
  • 79km (49mi) NW of Kirtipur, Nepal
  • 81km (50mi) NW of Kathmandu, Nepal


  • 2015-04-25 06:11:26 (UTC)
  • 2015-04-25 11:56:26 – Nepal
  • 2015-04-25 11:41:26 (UTC+05:30) – India



Source: US Geological Survey


Summary of today’s earthquake and second quake in Nepal according to the Indian Meteorological Department

Local time (Nepal time)
11:56 AM – 7.5
12:30 PM – 6.6

(11:41 AM in India – the main quake – according to India time that is 15 minutes behind Nepal)

The USGS maintains it at 7.5. Same is the assessment by the IMD. Though some reports talk of the revised estimates of 7.9 at the Richter Scale.

Indian Prime Minister has spoken about it and tweeted about it. Pictures of destruction are now pouring in.

According to the reports, the quake-affected areas are basically human habitations – including Kathmandu (the pictures of the place are now available).

We can assess the extent of damage in Nepal as it has left a trail even in India affecting Metro Rail services in Kolkata where cracks have appeared in the tunnel.

The shocks and aftershocks were felt in many parts of North and North-eastern India including Delhi.

According to the US Geological Survey, the districts around the epicentre are – Lamjung (at 35km), Bharatpur (60Km), Pokhara (75Km), Kirtipur (76Km) and Kathmandu (at 77Km).

Any earthquake above 6 in an area of human habitation brings an unending series of destruction which dawns upon us as the time passes – some hours after the shocks.

Narendra Modi has called in a meeting at 3 PM to assess the extent of destruction in India and has spoken with his Nepali counterpart who is on a foreign tour at the moment.

While Nepal is at the centre and staring at a widespread damage, India, too, is trying to assess the trail of destruction after an earthquake that was felt even in Pakistan.

©/IPR: Santosh Chaubey –


M7.5 – 35km E of Lamjung, Nepal

Link to the interative map –


Nepal Quake USGS

Data Source – US128.165°N 84.725°E depth=11.9 km (7.4 mi)


  • 2015-04-25 06:11:26 (UTC)
  • 2015-04-25 11:56:26 – Nepal
  • 2015-04-25 (UTC+05:30) 11:41:26 – India

(According to India time that is 15 minutes behind Nepal.)


Intensity MAP - USGS


• 35km (22mi) E of Lamjung, Nepal
• 60km (37mi) NNE of Bharatpur, Nepal
• 75km (47mi) E of Pokhara, Nepal
• 76km (47mi) NW of Kirtipur, Nepal
• 77km (48mi) NW of Kathmandu, Nepal


Seismotectonics of the Himalaya and Vicinity

Seismicity in the Himalaya dominantly results from the continental collision of the India and Eurasia plates, which are converging at a relative rate of 40-50 mm/yr. Northward underthrusting of India beneath Eurasia generates numerous earthquakes and consequently makes this area one of the most seismically hazardous regions on Earth. The surface expression of the plate boundary is marked by the foothills of the north-south trending Sulaiman Range in the west, the Indo-Burmese Arc in the east and the east-west trending Himalaya Front in the north of India.

The India-Eurasia plate boundary is a diffuse boundary, which in the region near the north of India, lies within the limits of the Indus-Tsangpo (also called the Yarlung-Zangbo) Suture to the north and the Main Frontal Thrust to the south. The Indus-Tsangpo Suture Zone is located roughly 200 km north of the Himalaya Front and is defined by an exposed ophiolite chain along its southern margin. The narrow (<200km) Himalaya Front includes numerous east-west trending, parallel structures. This region has the highest rates of seismicity and largest earthquakes in the Himalaya region, caused mainly by movement on thrust faults. Examples of significant earthquakes, in this densely populated region, caused by reverse slip movement include the 1934 M8.1 Bihar, the 1905 M7.5 Kangra and the 2005 M7.6 Kashmir earthquakes. The latter two resulted in the highest death tolls for Himalaya earthquakes seen to date, together killing over 100,000 people and leaving millions homeless. The largest instrumentally recorded Himalaya earthquake occurred on 15th August 1950 in Assam, eastern India. This M8.6 right-lateral, strike-slip, earthquake was widely felt over a broad area of central Asia, causing extensive damage to villages in the epicentral region. The Tibetan Plateau is situated north of the Himalaya, stretching approximately 1000km north-south and 2500km east-west, and is geologically and tectonically complex with several sutures which are hundreds of kilometer-long and generally trend east-west. The Tibetan Plateau is cut by a number of large (>1000km) east-west trending, left-lateral, strike-slip faults, including the long Kunlun, Haiyuan, and the Altyn Tagh. Right-lateral, strike-slip faults (comparable in size to the left-lateral faults), in this region include the Karakorum, Red River, and Sagaing. Secondary north-south trending normal faults also cut the Tibetan Plateau. Thrust faults are found towards the north and south of the Tibetan Plateau. Collectively, these faults accommodate crustal shortening associated with the ongoing collision of the India and Eurasia plates, with thrust faults accommodating north south compression, and normal and strike-slip accommodating east-west extension.

Along the western margin of the Tibetan Plateau, in the vicinity of south-eastern Afghanistan and western Pakistan, the India plate translates obliquely relative to the Eurasia plate, resulting in a complex fold-and-thrust belt known as the Sulaiman Range. Faulting in this region includes strike-slip, reverse-slip and oblique-slip motion and often results in shallow, destructive earthquakes. The active, left-lateral, strike-slip Chaman fault is the fastest moving fault in the region. In 1505, a segment of the Chaman fault near Kabul, Afghanistan, ruptured causing widespread destruction. In the same region the more recent 30 May 1935, M7.6 Quetta earthquake, which occurred in the Sulaiman Range in Pakistan, killed between 30,000 and 60,000 people.

On the north-western side of the Tibetan Plateau, beneath the Pamir-Hindu Kush Mountains of northern Afghanistan, earthquakes occur at depths as great as 200 km as a result of remnant lithospheric subduction. The curved arc of deep earthquakes found in the Hindu Kush Pamir region indicates the presence of a lithospheric body at depth, thought to be remnants of a subducting slab. Cross-sections through the Hindu Kush region suggest a near vertical northerly-dipping subducting slab, whereas cross-sections through the nearby Pamir region to the east indicate a much shallower dipping, southerly subducting slab. Some models suggest the presence of two subduction zones; with the Indian plate being subducted beneath the Hindu Kush region and the Eurasian plate being subducted beneath the Pamir region. However, other models suggest that just one of the two plates is being subducted and that the slab has become contorted and overturned in places.

Shallow crustal earthquakes also occur in this region near the Main Pamir Thrust and other active Quaternary faults. The Main Pamir Thrust, north of the Pamir Mountains, is an active shortening structure. The northern portion of the Main Pamir Thrust produces many shallow earthquakes, whereas its western and eastern borders display a combination of thrust and strike-slip mechanisms. On the 18 February 1911, the M7.4 Sarez earthquake ruptured in the Central Pamir Mountains, killing numerous people and triggering a landside, which blocked the Murghab River.

Further north, the Tian Shan is a seismically active intra-continental mountain belt, which extends 2500 km in an ENE-WNW orientation north of the Tarim Basin. This belt is defined by numerous east-west trending thrust faults, creating a compressional basin and range landscape. It is generally thought that regional stresses associated with the collision of the India and Eurasia plates are responsible for faulting in the region. The region has had three major earthquakes (>M7.6) at the start of the 20th Century, including the 1902 Atushi earthquake, which killed an estimated 5,000 people. The range is cut through in the west by the 700-km-long, northwest-southeast striking, Talas-Ferghana active right-lateral, strike-slip fault system. Though the system has produced no major earthquakes in the last 250 years, paleo-seismic studies indicate that it has the potential to produce M7.0+ earthquakes and it is thought to represent a significant hazard.

The northern portion of the Tibetan Plateau itself is largely dominated by the motion on three large left-lateral, strike-slip fault systems; the Altyn Tagh, Kunlun and Haiyuan. The Altyn Tagh fault is the longest of these strike slip faults and it is thought to accommodate a significant portion of plate convergence. However, this system has not experienced significant historical earthquakes, though paleoseismic studies show evidence of prehistoric M7.0-8.0 events. Thrust faults link with the Altyn Tagh at its eastern and western termini. The Kunlun Fault, south of the Altyn Tagh, is seismically active, producing large earthquakes such as the 8th November 1997, M7.6 Manyi earthquake and the 14th November 2001, M7.8 Kokoxili earthquake. The Haiyuan Fault, in the far north-east, generated the 16 December 1920, M7.8 earthquake that killed approximately 200,000 people and the 22 May 1927 M7.6 earthquake that killed 40,912.

The Longmen Shan thrust belt, along the eastern margin of the Tibetan Plateau, is an important structural feature and forms a transitional zone between the complexly deformed Songpan-Garze Fold Belt and the relatively undeformed Sichuan Basin. On 12 May 2008, the thrust belt produced the reverse slip, M7.9 Wenchuan earthquake, killing over 87,000 people and causing billions of US dollars in damages and landslides which dammed several rivers and lakes.

Southeast of the Tibetan Plateau are the right-lateral, strike-slip Red River and the left-lateral, strike-slip Xiangshuihe-Xiaojiang fault systems. The Red River Fault experienced large scale, left-lateral ductile shear during the Tertiary period before changing to its present day right-lateral slip rate of approximately 5 mm/yr. This fault has produced several earthquakes >M6.0 including the 4 January 1970, M7.5 earthquake in Tonghai which killed over 10,000 people. Since the start of the 20th century, the Xiangshuihe-Xiaojiang Fault system has generated several M7.0+ earthquakes including the M7.5 Luhuo earthquake which ruptured on the 22 April 1973. Some studies suggest that due to the high slip rate on this fault, future large earthquakes are highly possible along the 65km stretch between Daofu and Qianning and the 135km stretch that runs through Kangding.

Shallow earthquakes within the Indo-Burmese Arc, predominantly occur on a combination of strike-slip and reverse faults, including the Sagaing, Kabaw and Dauki faults. Between 1930 and 1956, six M7.0+ earthquakes occurred near the right-lateral Sagaing Fault, resulting in severe damage in Myanmar including the generation of landslides, liquefaction and the loss of 610 lives. Deep earthquakes (200km) have also been known to occur in this region, these are thought to be due to the subduction of the eastwards dipping, India plate, though whether subduction is currently active is debated. Within the pre-instrumental period, the large Shillong earthquake occurred on the 12 June 1897, causing widespread destruction.

Source: US Geological Survey