Question: What magnitude earthquake struck the national physical laboratory in India on September 2011?

full_context: Document 1: Houston: The Houston area has over 150 active faults (estimated to be 300 active faults) with an aggregate length of up to 310 miles (500 km), including the Long Point–Eureka Heights fault system which runs through the center of the city. There have been no significant historically recorded earthquakes in Houston, but researchers do not discount the possibility of such quakes having occurred in the deeper past, nor occurring in the future. Land in some areas southeast of Houston is sinking because water has been pumped out of the ground for many years. It may be associated with slip along the faults; however, the slippage is slow and not considered an earthquake, where stationary faults must slip suddenly enough to create seismic waves. These faults also tend to move at a smooth rate in what is termed "fault creep", which further reduces the risk of an earthquake.
Document 2: Seattle: Due to its location in the Pacific Ring of Fire, Seattle is in a major earthquake zone. On February 28, 2001, the magnitude 6.8 Nisqually earthquake did significant architectural damage, especially in the Pioneer Square area (built on reclaimed land, as are the Industrial District and part of the city center), but caused only one fatality. Other strong quakes occurred on January 26, 1700 (estimated at 9 magnitude), December 14, 1872 (7.3 or 7.4), April 13, 1949 (7.1), and April 29, 1965 (6.5). The 1965 quake caused three deaths in Seattle directly, and one more by heart failure. Although the Seattle Fault passes just south of the city center, neither it nor the Cascadia subduction zone has caused an earthquake since the city's founding. The Cascadia subduction zone poses the threat of an earthquake of magnitude 9.0 or greater, capable of seriously damaging the city and collapsing many buildings, especially in zones built on fill.
Document 3: April 2015 Nepal earthquake: Thousands of houses were destroyed across many districts of the country, with entire villages flattened, especially those near the epicenter.
Document 4: Delhi: Delhi Union territory and Megacity National Capital Territory of Delhi From top clockwise: Lotus temple, Humayun's Tomb, Connaught Place, Akshardham temple and India Gate Location of Delhi in India Coordinates: 28 ° 36 ′ 36 ''N 77 ° 13 ′ 48'' E ﻿ / ﻿ 28.61000 ° N 77.23000 ° E ﻿ / 28.61000; 77.23000 Coordinates: 28 ° 36 ′ 36 ''N 77 ° 13 ′ 48'' E ﻿ / ﻿ 28.61000 ° N 77.23000 ° E ﻿ / 28.61000; 77.23000 Country India Settled 6th century B.C. Incorporated 1857 Capital formation 1911 Formation of Union Territory 1956 Formation of NCT 1 February 1992 Capital New Delhi Districts 11 Government Body Government of Delhi Lt. Governor Anil Baijal, IAS Chief Minister Arvind Kejriwal (AAP) Deputy Chief Minister Manish Sisodia Chief Secretary Anshu Prakash, IAS Commissioner of Police Amulya Patnaik, IPS Area Union territory 1,484.0 km (573.0 sq mi) Water 18 km (6.9 sq mi) Area rank 31st Elevation 200 -- 250 m (650 -- 820 ft) Population (2011) Union territory 16,787,941 Density 11,312 / km (29,298 / sq mi) Urban 16,349,831 (2nd) Megacity 11,034,555 (2nd) Metro (2016) 26,454,000 (1st) Demonym (s) Delhiite Languages Official Hindi English Additional official Punjabi Urdu GDP Nominal (NCT) ₹6.86 lakh crore (US $100 billion) (2017 - 18) Nominal per capita ₹329,093 (US $4,800) (2017 - 18) Metro GDP / PPP $167 -- 370 billion Time zone IST (UTC + 5.30) Pincode (s) 1100XX Area code (s) + 91 11 ISO 3166 code IN - DL Website delhi.gov.in
Document 5: Delhi: Delhi Union territory and Megacity National Capital Territory of Delhi From top clockwise: Lotus temple, Humayun's Tomb, Connaught Place, Akshardham temple and India Gate Location of Delhi in India Coordinates: 28 ° 36 ′ 36 ''N 77 ° 13 ′ 48'' E ﻿ / ﻿ 28.61000 ° N 77.23000 ° E ﻿ / 28.61000; 77.23000 Coordinates: 28 ° 36 ′ 36 ''N 77 ° 13 ′ 48'' E ﻿ / ﻿ 28.61000 ° N 77.23000 ° E ﻿ / 28.61000; 77.23000 Country India Settled 6th century B.C. Incorporated 1857 Capital formation 1911 Formation of Union Territory 1956 Formation of NCT 1 February 1992 Capital New Delhi Districts 11 Government Body Government of Delhi Lt. Governor Anil Baijal, IAS Chief Minister Arvind Kejriwal (AAP) Chief Secretary Anshu Prakash, IAS Commissioner of Police Amulya Patnaik, IPS Area Union territory 1,484.0 km (573.0 sq mi) Water 18 km (6.9 sq mi) Area rank 31st Elevation 200 -- 250 m (650 -- 820 ft) Population (2011) Union territory 16,787,941 Density 11,312 / km (29,298 / sq mi) Urban 16,349,831 (2nd) Megacity 11,034,555 (2nd) Metro (2016) 26,454,000 (1st) Demonym (s) Delhiite Languages Official Hindi and English Additional official Punjabi and Urdu Time zone IST (UTC + 5.30) Pincode (s) 1100XX Area code (s) + 91 11 ISO 3166 code IN - DL Metro GDP (PPP) $167 to $370 billion Website delhi.gov.in
Document 6: National Physical Laboratory of India: The National Physical Laboratory of India, situated in New Delhi, is the measurement standards laboratory of India. It maintains standards of SI units in India and calibrates the national standards of weights and measures.
Document 7: New Delhi: New Delhi lies on several fault lines and thus experiences frequent earthquakes, most of them of mild intensity. There has, however, been a spike in the number of earthquakes in the last six years, most notable being a 5.4 magnitude earthquake in 2015 with its epicentre in Nepal, a 4.7-magnitude earthquake on 25 November 2007, a 4.2-magnitude earthquake on 7 September 2011, a 5.2-magnitude earthquake on 5 March 2012, and a swarm of twelve earthquakes, including four of magnitudes 2.5, 2.8, 3.1, and 3.3, on 12 November 2013.
Document 8: New Delhi: The city is home to numerous international organisations. The Asian and Pacific Centre for Transfer of Technology of the UNESCAP servicing the Asia-Pacific region is headquartered in New Delhi. New Delhi is home to most UN regional offices in India namely the UNDP, UNODC, UNESCO, UNICEF, WFP, UNV, UNCTAD, FAO, UNFPA, WHO, World Bank, ILO, IMF, UNIFEM, IFC and UNAIDS.
Document 9: Southern California: Many faults are able to produce a magnitude 6.7+ earthquake, such as the San Andreas Fault, which can produce a magnitude 8.0 event. Other faults include the San Jacinto Fault, the Puente Hills Fault, and the Elsinore Fault Zone. The USGS has released a California Earthquake forecast which models Earthquake occurrence in California.
Document 10: New Delhi: New Delhi is home to Indira Gandhi Memorial Museum, National Gallery of Modern Art, National Museum of Natural History, National Rail Museum, National Handicrafts and Handlooms Museum, National Philatelic Museum, Nehru Planetarium, Shankar's International Dolls Museum. and Supreme Court of India Museum.
Document 11: Istanbul: Istanbul is near the North Anatolian Fault, close to the boundary between the African and Eurasian Plates. This fault zone, which runs from northern Anatolia to the Sea of Marmara, has been responsible for several deadly earthquakes throughout the city's history. Among the most devastating of these seismic events was the 1509 earthquake, which caused a tsunami that broke over the walls of the city and killed more than 10,000 people. More recently, in 1999, an earthquake with its epicenter in nearby İzmit left 18,000 people dead, including 1,000 people in Istanbul's suburbs. The people of Istanbul remain concerned that an even more catastrophic seismic event may be in the city's near future, as thousands of structures recently built to accommodate Istanbul's rapidly increasing population may not have been constructed properly. Seismologists say the risk of a 7.6-magnitude or greater earthquake striking Istanbul by 2030 is more than 60 percent.
Document 12: New Delhi: The national capital of India, New Delhi is jointly administered by both the Central Government of India and the local Government of Delhi, it is also the capital of the National Capital Territory (NCT) of Delhi.
Document 13: New Delhi: With a total area of 42.7 km2 (16.5 sq mi), New Delhi forms a small part of the Delhi metropolitan area. Because the city is located on the Indo-Gangetic Plain, there is little difference in elevation across the city. New Delhi and surrounding areas were once a part of the Aravalli Range; all that is left of those mountains is the Delhi Ridge, which is also called the Lungs of Delhi. While New Delhi lies on the floodplains of the Yamuna River, it is essentially a landlocked city. East of the river is the urban area of Shahdara. New Delhi falls under the seismic zone-IV, making it vulnerable to earthquakes.
Document 14: National Institute of Science Communication and Information Resources: The National Institute of Science Communication and Information Resources (NISCAIR), located at New Delhi, India, is an information science institute in India founded in 2002. It operates under the umbrella of the Council of Scientific and Industrial Research (CSIR) that comprise 38 other labs and institutes in India.
Document 15: New Delhi: New Delhi (i/ˌnjuː ˈdɛli/) is a municipality and district in Delhi which serves as the capital and seat of government of India. In addition, it also serves as the seat of Government of Delhi.
ground_truth: 4.2-magnitude
sub_queries: where is the national physical laboratory located in india Answer: in New Delhi
What was the magnitude of the earthquake that affected in New Delhi on September 2011? Answer: 4.2-magnitude