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49-617: A partial visualization of an active fault trace that aligns with the present-day Sagaing Fault trace was recorded by Fritz Noetling, a geologist, in the book The Miocene of Burma published in 1900. In 1913, Thomas Henry Digges La Touche of the Geological Survey of India acknowledged the existence of a plate boundary feature along the Shan Plateau's western margin in Mandalay, including the one dividing metamorphic stratas of

98-600: A left stepover leads to the Ban Mauk segment 10 km (6.2 mi) west. Between the stepover is a series of northeast–southwest striking faults that cuts through a transpressional ridge. Many are shorter than 20 km (12 mi) long and some show normal-component in their slip; however their weak expression suggest small slip rates compared to the Sagaing Fault's main branches. The Ban Mauk segment runs from 23.8°N and continues for 150 km (93 mi). Due to

147-581: A maximum intensity of IX to X on the Rossi–Forel scale . The city of Pegu, Rangoon and several other towns were destroyed. In Pegu, fires erupted, and severe liquefaction caused further damage. Approximately 500 people died in Pegu while 58 were killed in Rangoon. More deaths were recorded in other villages. It triggered a small tsunami which inundated villages along the coast. This is the deadliest earthquake in

196-549: A northwest–southeast striking thrust fault. One of these segments produced a M w   7.6 earthquake in January 1931, though due to the lack of seismic data and isoseismal map its origin segment remains tentative. However, shaking was more intense along the Kamaing segment. Damaging earthquakes have been associated with the fault for centuries. The great 1839 Ava earthquake killed hundreds and damaged many cities, including

245-632: A reverse fault expressed on the feature's eastern side. This feature is due to a small transpressional component where the segment experiences crustal compression. A majority of the segment ruptured during a M w   7.3 earthquake in December 1930 which originated at its southern limit. The Naypyidaw segment consists of two parallel strands that branches out at 19.1°N for its entire 70 km (43 mi). Both strands cut through channels and alluvial fans. The western strand runs east of Naypyidaw. A damaging but moderate earthquake in close proximity to

294-408: A segment south of the 1946 rupture. In 1991, a small seismic gap between the two 1946 ruptures generated an M w   7.0 earthquake, partially re-rupturing a small section of the 1946 quakes, killing two. The 2012 Shwebo earthquake was the most recent major event on the Sagaing Fault. It had a moment magnitude of 6.8 and ruptured the fault north of Mandalay. A detailed and thorough evaluation of

343-482: A ~300 km (190 mi) rupture . Researchers at National Taiwan University combined lidar and macroseismic data from historic accounts to estimate its magnitude at ~M w   7.9 and rupture length to be 285–325 km (177–202 mi). The 1839 earthquake ruptured two segments; the Meiktila segment in the south and Sagaing segment in the north. They estimated 5.5 m (18 ft) of displacement on

392-436: Is Burma's largest and most active source of seismic threat, running through or close to major cities like Yangon, Nay Pyi Daw and Mandalay . Several large and damaging earthquakes have occurred on this fault in historical times. In 1946 the 180 km (110 mi) long Sagaing segment produced two major earthquakes but there are no records of its impact. Ten years later, in 1956 , a magnitude 7.1 earthquake struck close to

441-575: Is a mostly continental transform fault that runs through Burma and connects the Andaman spreading center to the collision zone in the north. It accommodates motion between the Burma and Sunda plates as they slide past each other at a rate of 18 to 49 mm/yr. The fault runs the entire length of the country for over 1,200 km and continues its trace into the Andaman Sea. The Sagaing Fault

490-605: Is a scientific agency of India. It was founded in 1851, as a Government of India organization under the Ministry of Mines , one of the oldest of such organisations in the world and the second oldest survey in India after the Survey of India (founded in 1767), for conducting geological surveys and studies of India , and also as the prime provider of basic earth science information to government, industry and general public, as well as

539-452: Is designated a seismic gap due to the absence of major earthquake ruptures since at least 1897. At least 2 m (6 ft 7 in) of slip has accumulated along the fault corresponding to a magnitude 7.9 earthquake. Another seismic gap running 180 km (110 mi) lies in the Andaman Sea south of Yangon, potentially generating a magnitude 7.7 earthquake. Geological Survey of India The Geological Survey of India ( GSI )

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588-435: Is no magnitude assigned to this event. The book Southeast Asia Association of Seismology is the only published work mentioning this event. The largest earthquake in the sequence, an M w   7.6 quake, struck next to Indawgyi Lake , resulting in large landslides and ground failures . There were no casualties in this earthquake. Another violent earthquake of unknown magnitude occurred 146.5 km north of Pyu. It

637-535: The British Geological Survey , was appointed 'Surveyor of coal districts and superintendent of coal works, Bengal' on 3 December 1845 and arrived in India the following February. The phrase "Geological Survey of India" was first used on his Dec 1847 map of the Damoodah and Adji Great Coal Field , together with Horizontal and Vertical sections of the map. On 4 February 1848, he was appointed

686-404: The P wave . Fast-propagating ruptures can inflict trememdous damage. The Sagaing Fault's relatively straight geometry, the longest continuous observed worldwide, could sustain supershear ruptures. Due to the fault's proximity to populated areas, supershear earthquakes can have devastating effects. The length of fault running 260 km (160 mi) from 19.2°N to 21.5°N, on the Meiktila segment,

735-585: The "Geological Surveyor of the Geological Survey of India", but he fell off his elephant and, soon after, died with his assistant, F. B. Jones, of 'jungle fever' on 15 November 1848, after which John McClelland took over as the "Officiating Surveyor" until his retirement on 5 March 1851. Until 1852, Geological Survey primarily remained focused on exploration for coal, mainly for powering steam transport, oil reserves, and ore deposits, when Sir Thomas Oldham , father of Richard Dixon Oldham , broadened

784-706: The "Sagaing Fault". He also made the first description of the fault in Rift features at the Sagaing Tagaung Ridge at the Fifth Burma Research Congress. He determined the fault running nearly the entire length of Myanmar from south to north had a strike-slip mechanism, and linked it to historical earthquakes. A 1991 study of the fault determined a total displacement of 203 km (126 mi) and slip rate of 22 mm (0.87 in) per year by analyzing two metamorphic units and assuming

833-570: The 1929–1931 sequence. Two moderate foreshocks occurred on the night of December 3. The first lasted 5 seconds, generated some panic, and it was felt in Pyinmana and Rangoon. The other foreshock was described as being stronger than the first, but was not felt as widespread as the first. Violent shaking from an M w   7.3 earthquakedisrupted the early morning of December 4 in Pyu , Taungoo District . The December 4 event occurred further north of

882-561: The Bago segment ruptured during a M w   7.4 earthquake in May 1930 with offsets of at least 3 m (9.8 ft). The Pyu segment begins where the Bago segment terminated and continues 130 km (81 mi) to 19.1°N. It runs along the base of the Bago-Yoma range. There lies a terrace along the central part of the segment east of the fault trace which represents the hanging wall of

931-642: The Irrawaddy River from 21.9°N to 22.6°N, where it offsets alluvial fans of the post-Pliocene. It cuts through the Singu Plateau and splits into two segments running east and west of the river. Its western strand to the north is the Tawma segment. In 1946, a M w   7.7 earthquake was likely associated with the segment's northern two-thirds. This segment also ruptured during a smaller M w   6.8 earthquake in 2012. The remaining portion to

980-527: The Irrawaddy River's northern bank; continuing its north–northeasternly trace. A 3 km (1.9 mi) wide pull-apart basin at 24.25°N separates it from the Mawlu segment where it continues north–northwest for 90 km (56 mi). The combined length of both segments is estimated at 170 km (110 mi). Geodetic analysis of these segments revealed an annual strain accumulation of about 2 cm (0.79 in). A M w   7.3 foreshock occurred along

1029-568: The May and December 1930 earthquakes occurred during this active period, they were separate events, unrelated to the activity in the northern part. The December 1930 earthquake, however, was triggered due to stress transfer from the previous event in May. A lesser-known earthquake on July 18, 1930, in the Ayeyarwady Region killed about 50 people. According to the National Centers for Environmental Information database, there

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1078-619: The Naga Hills, beyond 26.7°N. Right-lateral displacements are also well-expressed in drainage channels on the eastern flank of the Naga Hills at its northern termination. The fault continues north and joins a thrust fault system associated with the Assam Valley. the Mogang segment, the most active of the three, though less seismically active than the Kamaing segment, runs in a broad arc from 24.8°N. It ends at 26.8°N where it transforms into

1127-624: The Pegu Range in August 1929. There are insufficient reports of damage caused by this earthquake, although it was said that buildings were swaying and objects were displaced at Yamethin , roughly 133.6 km north of the quake epicenter. The magnitude of this earthquake was no greater than 7.0. On the night of May 5, a large shock registering M w   7.5 struck north of the city of Pegu resulting in widespread deaths and destruction. There were no foreshocks that preceded. The earthquake had

1176-674: The Sagaing Hills from the Central Tertiary Basin. While analysing historical earthquakes in Myanmar, Harbans Lal Chhibber (1934) discovered a linear trace when joining their epicenters which he inferred to be along the same fault. In 1970, Aung Khin and others confirmed the fault's existence using geophysical techniques and a Bouguer gravity investigation from Taungoo to Thabeikkyin . That same year, Win Swe nomenclated it

1225-558: The Sagaing segment while slip on the Meiktila segment was around 3.8 m (12 ft). The felt area based on the Modified Mercalli intensity was larger than the 1912 Maymyo earthquake (M w   7.7) and similar in area to the 2002 Denali earthquake (M w   7.9). The maximum assigned Modified Mercalli intensity was XI ( Extreme ). The mainshock was preceded by a large foreshock in 1838, which also damaged

1274-439: The accumulation of stress towards the south, where the future 1931 quake would take place. Similarly, the 1946 earthquake rupture segments were directly south of the 1931 rupture. The first mainshock in the 1946 doublet sequence then triggered the second mainshock due to the sudden increase in stress levels on the fault. Ten years later, an M w   7.1 earthquake near Mandalay killed at least 40 people. That earthquake broke

1323-424: The ambit of the scope of functioning of the Geological Survey of India by advancing the argument with the government that it was not possible to find coal without first mapping the geology of India. Thus, the Geological Survey commenced to map the rock types, geological structures and relative ages of different rock types . The age of rock strata was estimated from the presence of index fossils , which consumed much of

1372-433: The basis for its overall lack of seismic activity, the Meiktila segment is believed to have ruptured during the earthquake. This segment runs from Nay Pyi Taw to Mandalay, a length of about 260 km (160 mi). Remote sensing and field observation revealed a maximum displacement of 5–7 m (16–23 ft) along the trace of the 1839 rupture just outside Mandalay. This would place the magnitude at 7.4–8.0+ and generate

1421-651: The basis of the Report of a High-level Committee chaired by Mr S.Vijay Kumar Additional Secretary in the Ministry of Mines of the Government of India. 1839 Ava earthquake The 1839 Ava earthquake , also known as the Amarapura earthquake or Inwa earthquake , was a disastrous seismic event that struck present-day central Myanmar on March 23. This earthquake with an estimated moment magnitude as high as 8.3,

1470-570: The capital. Great damage was reported in Inwa , so severe that the formal capital was moved to nearby Amarapura . In Mingun , a stupa sustained serious damage as a result of shaking. British officials in Myanmar recorded catastrophic damage and liquefaction in Mandalay and the surrounding area. Many pagodas collapsed during the event. Chasms and fissures more than 10 ft (3.0 m) wide were seen in Amarapura and nearly every brick building

1519-498: The city of Mandalay, re-rupturing the 1839 rupture zone for about 60 km (37 mi). Meanwhile, the 260 km (160 mi) long Meiktila segment has not experienced any major earthquake since 1839 and is considered a seismic gap . The Meiktila and Sagaing segment of the fault ruptured during this earthquake for a length of 400 km (250 mi), corresponding to a magnitude 8.1–8.3 earthquake, although little research has been conducted to provide further constrains. On

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1568-492: The diameter of the Earth's core. On 8 April 2017 GSI began pilot project, with the first ever aerial survey of mineral stocks by GSI, to map the mineral stocks up to a depth of 20 km using specially-equipped aircraft. The GSI was restructured into 5 Missions, respectively relating to "Baseline Surveys";"Mineral resource Assessments";"Geoinformatics";"Multi-disciplinary Geosciences"; and "Training and Capacity Building", on

1617-410: The epicenter of the May earthquake, about 6.4 to 9.7 km west southwest of Pyu. Damage was severe, with a railroad being shifted off and twisted, while many buildings in the city collapsed. About 30 people were killed. The maximum intensity was assigned X on the Rossi–Forel scale . This event is not an aftershock of the May quake because it ruptured a different segment of the Sagaing Fault. Although

1666-452: The event suggested the rupture was estimated at 45-km-long. The centroid moment tensor solution suggested the earthquake ruptured a north–south trending and sub-vertical fault that steeply dipped to the east. The Sagaing Fault was dubbed an "earthquake fault superhighway" for to its potential to promote supershear earthquakes . Such events occur when an earthquake's rupture velocity exceeds its S wave velocity and potentially reaching that of

1715-562: The fault is about 100 km, although several authors have proposed between 360 km to 400 km. The southern section comprises, from south to north, the Bago, Pyu, Naypyidaw, Meiktila and Sagaing segments. The 170 km (110 mi) Bago segment runs from Myanmar's coast, southeast of Yangon, to 18°N, where the fault experiences a sharp bend. The southern termination and offshore section remains uncertain, however, several tens of kilometers offshore, it connects to normal faults striking east–west. Approximately 100 km (62 mi) of

1764-551: The fault offsets a stream by 2.4 km (1.5 mi); the largest observable offset along the segment. Although no major historical earthquake has been clearly associated with the segment, a possible contender is the 1839 Ava earthquake which destroyed the city of Inwa and caused severe damage to areas east and south of the Irrawaddy River . The geomorphologic features of the Sagaing segment led to its discovery in 1970. This segment runs relatively linear; it runs west of

1813-481: The fault runs uninterrupted by large stepovers for most of its length, the northern 400 km (250 mi) branches outwards in a "horsetail" fashion into individual segments 100 km (62 mi) in width. The total slip rate across the Indian–Sunda plate boundary is about 35 mm/yr, of which 18 mm/yr is accommodated by the Sagaing Fault, according to GPS data. The measured maximum displacement along

1862-570: The fault's origins in the end Oligocene or early Miocene. The Sagaing Fault begins offshore in the Andaman Sea at a divergent boundary before passing through the central Myanmar basin . The fault has a relatively low topographical relief for most of its length compared to the Shan Scarp Fault to the west . Its total length from the Eastern Himalayan Syntaxis to the Andaman Sea is 1,400 km (870 mi). While

1911-1110: The geologists' efforts in finding these index fossils, as the method of Radiometric dating for estimating the age of rock strata was not developed at that time. In 1869 Frederick Richard Mallet was first to visit Ramgarh crater . Later studies include by those of Arthur Lennox Coulson In 19th century GSI undertook several surveys including Great Trigonometrical Survey , 1869 Kailash - Mansarovar expedition, 1871-1872 Shigache – Lhasa expedition, 1873-1874 Yarkand – Kashgar expedition, second expedition of this area by Sir Thomas Douglas Forsyth , 1878-1882 Darjeeling – Lhasa – Mongolia expedition, etc. The native surveyors were called pandit , some notable ones include cousins Nain Singh Rawat and Krishna Singh Rawat . In 19th and early 20th century GSI made important contributions to Seismology by its studies and detailed reports on numerous Indian earthquakes. Richard Dixon Oldham , like his father also worked for GSI, first correctly identified p- and s-waves , and hypothesised and calculated

1960-543: The in Daw segment three minutes before the M w   7.7 earthquake in 1946. The fault branches into three segments where the Mawlu segment terminates: the Shaduzup, Kamaing, and Mogang segments. The Shaduzup segment, the westernmost of the three, is not believe to exceed 120 km (75 mi). The lack of clear geomorphic features suggest less activity occurs on this segment. The Kamaing segment continues further north into

2009-400: The largest in the country. Not much about this event is known due to sparse records. Looking back at the historical records of earthquakes, the years 1906 and 1908 saw two major events in the northernmost end of the Sagaing Fault. The 1906 Putao earthquake on August 31 had an estimated moment magnitude of 7.0, and the 1908 earthquake measured M w   7.5. The 1908 earthquake resulted in

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2058-410: The official participant in steel, coal, metals, cement, power industries and international geoscientific forums. Formed in 1851 by East India Company , the organization's roots can be traced to 1836 when the "Coal Committee", followed by more such committees, was formed to study and explore the availability of coal in the eastern parts of India . David Hiram Williams , one of the first surveyors for

2107-525: The rarity of clear geomorphic offsets associated with this segment, its slip rate is inferred to be low. The segment marks the boundary between the Neogene volcanics of the west and Miocene sedimentary strata of the east. At 25°N, the fault trace disappears, buried by clastic deposits of the Taungthonton Volcano to the east. At 23.7°N, the in Daw segment branches away from the Tawma segment at

2156-416: The segment in August 1929 damaged railroads and bridges 40 km (25 mi) south of Naypyidaw. The International Seismological Centre assigned the earthquake M w   6.5. The Meiktila segment runs 220 km (140 mi) through a wide valley from Naypyidaw to Mandalay. This segment does not produce any dip-slip movement, evident from the absence of elevation differences across the fault. At 20°N,

2205-429: The south likely ruptured during the destructive M w   7.1 earthquake in 1956. The Sagaing Fault begins to fan outwards in a "horsetail" fashion into four separate fault zones from 23.5°N. The Tawma segment runs along an east-facing scarp and streams display dextral offsets. The western strand of the Sagaing segment extends north and is represented by the Tawma segment. The trace is no longer visible at 24°N where

2254-463: The then imperial capital Inwa . That earthquake is thought to have a moment magnitude of 8.0 or greater. The large magnitude would imply a rupture length of at least 300 km along the fault. In the early 20th century, from 1929 to 1931, more than half the length of the Sagaing Fault was involved in significant earthquakes. The first earthquake—which was followed-up by subsequent larger events—struck southwest of Nay Pyi Daw, and east of Thayetmyo in

2303-781: The west coast of the Coco Islands, off the Rahkine coast, and into Bangladesh , is a highly oblique convergent boundary known as the Sunda megathrust . This large fault marks the boundary between the Indian and Burma plates. The megathrust emerges from the seafloor in Bangladesh, where it runs parallel and east of the Chin Hills . This boundary continues to north of Burma where it ends at the eastern Himalayas . The Sagaing Fault

2352-711: Was felt in Mandalay and Thanatpin . Six brick buildings sustained damage. On August 19, another tremor caused cracks to appear in buildings in Mandalay and lightly affected Kalaw . The city was rocked another time, resulting in the collapse of the Shwe Sandaw Pagoda in Taungoo. Several short tremors woke people up in Taungoo, Pyuntaza and Nangyun . Two powerful earthquakes north of Mandalay measuring M w   7.3 and 7.7 occurred on September 12, 1946. The doublet earthquake sequence would remain as one of

2401-629: Was one of the largest in the country, since 1762 . It was assigned a maximum of XI ( Extreme ) on the Modified Mercalli intensity scale , and was felt in Rangoon and Bhamo . Damage was enormous in Ava, resulting in the death of hundreds. Myanmar is wedged between four tectonic plates; the Indian , Eurasian , Sunda , and Burma plates , that interact due to active geological processes . Along

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