March 6, 1987 Earthquake: Napo Province, Quito, Tulcan, Ecuador

Name: March 6, 1987 Earthquake: Napo Province, Quito, Tulcan, Ecuador
Start: 1987-03-06
Location: Napo Province, Quito, Tulcan, Ecuador

March 6, 1987 · M7.2 · 5,000 deaths · $1.5 billion

A magnitude 7.2 earthquake struck Napo Province, Quito, Tulcan, Ecuador on March 6, 1987 at 04:10:44 UTC, 10 km below the surface. It killed 5,000 people.

Map

Where it struck, with the other significant earthquakes within 200 km. Circles are sized and colored by magnitude; select one for its page.

The earthquake

Date: March 6, 1987
Time: 04:10:44 UTC
Place: Napo Province, Quito, Tulcan, Ecuador
Magnitude: 7.2 (Mw)
Magnitude scales: Mw 7.2 · Ms 6.9 · mb 6.5
Focal depth: 10 km (6 mi)
Tsunami: None recorded
Epicenter: 0.083° N, 77.785° W
Country: Ecuador
Region: South America
USGS record: The USGS’s page for this earthquake

Mw: moment magnitude, based on the slip on the fault and the area that slipped. Ms: surface-wave magnitude. mb: body-wave (P-wave) magnitude. NCEI’s headline magnitude is the best of these for the earthquake.

The toll

Deaths: 5,000
Damage: $1.5 billion

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

From Wikipedia

The 1987 Ecuador earthquakes occurred over a six-hour period on March 6, 1987. The sequence of shocks measured 6.7, 7.1, and 6.0 on the moment magnitude scale. The main shock had a maximum Mercalli intensity of IX (Violent). The earthquakes were centered in Napo Province in northeast Ecuador; the epicenters were on the eastern slopes of the Andes, about 75 km ENE of Quito and 25 km north of Reventador Volcano. The earthquakes caused about 1,000 deaths. Four thousand people were missing and damage was estimated at US$1 billion.

Text from Wikipedia, “1987 Ecuador earthquakes”, licensed CC BY-SA 4.0. Quoted as written; the full article has the rest.

What happened

The USGS’s account of the effects of this earthquake.

Approximately 1,000 people killed, 4,000 missing, 20,000 homeles, extensive damage, landslides and ground cracks in Napo Province and in the Quito-Tulcan area, Ecuador. About 27 km. of the oil pipeline in Ecuador, between Lago Agrio and Balao, were destroyed or badly damaged. Landslides occurred in the Pasto-Mocoa area, Colombia. Felt (IV) at Iquitos, Peru. Felt strongly in many parts of Ecuador and southwestern Colombia. Also felt in central Colombia and northern Peru. FAULT PLANE SOLUTION: P-Waves NP1:Strike=353 Dip=72 Slip=90 NP2:Strike=173 Dip=18 Slip=90 Principal Axes: (T) Plg=63 Azm=263 (P) Plg=27 Azm=83 Comment: The focal mechanism is poorly controlled and corresponds to reverse faulting. The preferred fault plane is not determined. RADIATED ENERGY No. of sta: 4 Focal mech. F Energy 6.5+1.3*10**14 Nm MOMENT TENSOR SOLUTION Dep 49 No. of sta: 10 Moment Tensor; Scale 10**19 Nm Mrr=1.78 Mtt=1.57 Mff=-3.35 Mrt=-1.14 Mrf=1.64 Mtf=0.39 Principal axes: (T) Val=2.98 Plg=52 Azm=196 (N) Val=0.94 Plg=32 Azm=341 (P) Val=-3.92 Plg=17 Azm=82 Best Double Couple:Mo=3.5*10**19 NP1:Strike=211 Dip=40 Slip=147 NP2:Strike=327 Dip=70 Slip=55 CENTROID, MOMENT TENSOR (HRV) Data Used: GDSN, IDA L.P.B.: 15S, 39C M.W.: 13S, 32C Centroid Location: Origin Time 04:10:55.4 0.1 Lat 0.06S 0.01 Lon 77.84W 0.01 Dep 15.0 BDY Half-duration 14.0 Moment Tensor; Scale 10**19 Nm Mrr=5.03 0.04 Mtt=-0.12 0.04 Mff=-4.91 0.06 Mrt=0.26 0.11 Mrf=3.85 0.12 Mtf=-0.97 0.04 Principal Axes: (T) Val=6.35 Plg=71 Azm=268 (N) Val=0.04 Plg=3 Azm=8 (P) Val=-6.39 Plg=19 Azm=100 Best Double Couple:Mo=6.4*10**19 NP1:Strike=195 Dip=27 Slip=98 NP2:Strike=7 Dip=64 Slip=86

From the USGS event page for usp000330w. U.S. Geological Survey text and figures are in the public domain.

Magnitude estimates

The magnitudes the USGS catalog lists for this earthquake, by scale and by who computed them. NCEI’s own scales are in the table above.

Mag.	Scale	Computed by	Notes
7.2	Mw, moment	USGS National Earthquake Information Center	Preferred · Reviewed
7.14	Mw, moment	ISC-GEM global catalog	Final · ±0.1
7.1	Mwc, centroid moment	Global CMT project	Preliminary

What the record says

NCEI’s account, from the sources it cites.

1987, March, 6, 04:10:41.9 UTC. Approximately 1,000 people were killed, 4,000 missing, 20,000 homeless, extensive damage, landslides and ground cracks in Napo Province and in the Quito-Tulcan area, Ecuador. About 27 km of the oil pipeline in Ecuador, between Lago Agria and Balao, were destroyed or badly damaged. Landslides occurred in the Pasto-Mocoa area, Colombia. Felt (IV) at Iquitos, Peru. Felt strongly in many parts of Ecuador and southwestern Colombia. Also felt in central Colombia and northern Peru. (reference #1053)

1987, March 5. Carchi, Imbabura, Pastaza, Ecuador. 5000 dead, 150000 affected, $1500 million damage. (reference #1250)

1987, March 6, 04:10:44.44 UTC. 0.083 N, 77.785 W, 16.4 km depth, 7.2 Mw HRV, 7 Mw GS, 6.8 Ms ISC, 6.9 Ms NEIC, 6.7 Ms PAS, 7 Ms BRK, 6.4 mb ISC, 6.5 mb NEIC.

(reference #9910)

1987, March 6, 04:10:43.16 UTC, 0.002 S, 77.815 W, 10 km depth, 7.14 Mw. (reference #10476)

Sources NCEI cites

The publications NCEI lists for this record. The numbers match the “reference #” notes in its account above.

#1053 National Earthquake Information Center (NEIC) (1971 to 2013). Preliminary Determination of Epicenters (PDE), a weekly and monthly publication, National Earthquake Information Center, U.S. Geological Survey, Golden, Colorado, 1971 to 2013.
#1054 McClelland, Lindsay, et al, editors (1980-1989). SEAN Bulletin, a monthly publication of the Scientific Event Alert Network of the Smithsonian Institution, Washington, D.C.
#1231 Berz, G. (1988). List of Major Natural Disasters, 1960-1987. Natural Hazards, vol. 1, no. 1, p. 97-99.
#1232 International Seismological Centre (1964-1990). Regional Catalogue of Earthquakes, 1964-1990, Edinburgh, Scotland.
#1250 Centre for Research on the Epidemiology of Disasters (CRED) and the U.S. Office of Foreign Disaster Assistance (OFDA) (2001). EM-DAT: The OFDA/CRED International Disaster Database, Universite Catholique de Louvain, Brussels, Belgium, link
#9910 Engdahl, E.R., R. van der Hilst, R. Buland (2012). Centennial Earthquake Catalog. Retrieved August 11, 2011 from link
#10476 International Seismological Centre (2013). Final Scientific Report of the ISC-GEM Instrumental Earthquake Catalogue, ISC-GEM Global Instrumental earthquake Catalogue (1900-2021). Versions 1-12 downloaded beginning 18 March 2013. DOI: 10.31905/D808B825

Other significant earthquakes nearby

Within 200 km, the deadliest first.

Significant earthquakes of 1987 The 1900s Every quake the USGS located in 1987 Recent earthquakes near here This day in weather history

Sources

Significant earthquakes from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-10-01. NCEI earthquake 5130. The written accounts and the magnitude estimates are from the USGS earthquake catalog, event usp000330w, matched to this record by time, place and magnitude.