April 9, 1928 Earthquake: Peru

April 9, 1928, 17:34:15 UTC, 13 S, 69.5 W, magnitude 6.9, depth 30 km, intensity IX. (reference #1208)

April 9, 1928, 17:34:15 UTC, 13 S, 69.5 W, magnitude 6.9, depth 30 km. (reference #130)

April 9, 1928, 17:34:17.09 UTC, 13.595 S, 70.343 W, magnitude 6.71 Mw, depth 25 km. (reference #10476, v.11)

April 9, 1928, 12:30. There was a destructive earthquake in south-east Peru with a source under the eastern slopes of the Andes. Structures at Makusani, Ollachea, Aiapata and other places were destroyed and damaged. The strongest recurrent shock was on April 27 at 15:34. In some papers; it is apparently mistakenly indicated that in the region of Arequipa "considerable damage was done on the coast by the frequent tidal waves which followed this series of destructive shocks." Gutenberg, Richter (1954): April 9; 17h34m15s; 13 S., 69.5 W.; M=6.9. April 27; 20h34m58s; 13 S., 69.5 " W.; M=6.75. (reference #415)

On April 9, 1928, at 12:30 [local time], the Lima Observatory recorded a violent seismic movement coming from the SE. Later reports showed that a vast region of the province of Carabaya, department of Puno in the South Andes, had been shaken by an earthquake which caused serious destruction at Ayapata (3,600 m a.s.l.), capital of the district of that name. The village church, built of interlocking stones with a thatched roof and dating from the first days of the Colony, was half ruined; dwellings which were not destroyed were rendered uninhabitable. Likewise, the villages of Ituata and Macusani suffered serious damage. In the village of Ollachea, according to various witnesses, subterranean detonations were heard and then the shaking of the earth came. From snow-capped Allinocapae Peak enormous masses of ice broke loose with a crash.

According to the report of the authorities, the zone most affected comprised a rectangle 50 km from side to side, whose length was formed by part of the Esquilaya River to its debouchment into the Inambari, and whose width varied from 1 to 4 kilometers. Talus slides into the river formed a natural dam which later broke. Two were dead and eight missing as a result of the slides. The movement was felt intensely at Puno, Cuzco, Huancane, and the villages of Putina, and the hamlets of Vilquishco and Cuyocuyo. At La Paz, Bolivia, it was felt with intensity III on the MM scale. In "Seismicity of the Earth" this shock is assigned a focal time of 12:34:15.5 and a geographic location of 13 S, 69 W, magnitude 6.9, and focal depth of about thirty kilometers.

(above from reference #1111)