1947 Satipo earthquake

Earthquakes in Peru are mainly concentrated at the subduction zone where the Nazca Plate subducts beneath the South American Plate at the Peru–Chile Trench off its west coast. Another zone of seismicity is recorded within the South American Plate in the Andes region. In the high Andes, shallow earthquakes are the result of normal-faulting such as the 1946 Ancash earthquake which ruptured a shallow-dipping fault oriented parallel to the range. The western margin of the Cordillera Blanca in central Peru exhibits normal-faulting and coincides with extensional tectonics acting perpendicular to the range. ==Earthquake==

The mainshock occurred on 1 November at 14:58:57 UTC (09:58:57 local time) with an epicenter about south–southwest of Huancayo, in Junín province. It was a shallow intraplate earthquake that occurred within the South American Plate, having a focal depth of , and was the largest of its kind ever recorded in the sub-Andean region. The aftershocks that followed had epicenters distributed east of the mainshock. An analysis of data from seismic stations in Weston, Pasadena and Saint-Maur indicated that the mainshock was caused by vertical movement on a north-oriented fault plane that dipped 30°. The inferred dip angle was shallower than that of faults surveyed in the region. Within the epicenter region, two other earthquakes larger than magnitude 6.0 were recorded. In 1976, a 6.6 strike-slip earthquake occurred south of the 1947 earthquake epicenter at depth, and a 6.5–6.8 shock in 1982 occurred north of the 1947 earthquake with a left-lateral–reverse mechanism. ==Impact==

The earthquake was felt across a area encompassing nearly all of Peru. It was also felt across a large portion of Brazil from Tabatinga to the headwaters of the Acre River. A maximum Modified Mercalli intensity of VIII–IX (Severe–Violent) was assigned to a area. In the latter city, those attending church scrambled outdoors. According to the United States Geological Survey, 233 people were killed. However, deaths were only recorded in several towns such as Satipo, Andamarca, Acobamba, La Merced, Víctor, Comas, Perené and other towns, and the toll was not finalized. In the town of Satipo alone, at least 40 people died and many were missing, The earthquake destroyed or seriously damaged 63 percent of all adobe constructed homes in La Merced. An unknown number of people may have drowned when the Satipo River flooded while thousands were homeless. In the aftermath some injured victims were airlifted to Lima. The Minister of Agriculture, Pedro Venturo Zapata, visited the affected area and led in the recovery efforts. The Red Cross also flew in supplies to assist those affected by the earthquake and floods. ==See also==