Early Macroseismic Intensity Observations, Isoseismal Maps, and Instrumental Recordings of Earthquakes in Mexico (1888–1934): A Review

Abstract The macroseismic intensity observations and isoseismal maps by the Observatorio Meteorológico Central de México and the instrumental recordings of earthquakes by the Observatorio Astronómico Nacional, now mostly in oblivion, are a rich data source documenting late nineteenth–early twentieth-century earthquakes in Mexico and Guatemala. During 1877–1912, the meteorological observatory collected macroseismic data through the staff of its weather stations. Between July 1888 and November 1909, the observations were published in the seismology section of the Boletín del Observatorio Meteorológico-Magnético Central de México together with isoseismal maps for major earthquakes in southern Mexico and Guatemala such as the 18 April 1902 Guatemala, 23 September 1902 Chiapas, and 13 January 1903 offshore Chiapas earthquakes, and several earthquakes in Guerrero between 1902 and 1908. The Observatorio Astronómico Nacional recorded earthquakes on two Bosch–Omori seismometers (horizontal components) and a Schmidt trifilar gravimeter (vertical component). The readings (time, various phases, period, and amplitude) and the estimated distance of the focus appeared 1905–1908 in the annual catalogs of the International Seismological Association and were published from 1909 on in Mexican earthquake station bulletins. As a part of this review, facsimiles of the seismology sections in the Boletín del Observatorio Meteorológico-Magnético Central de México (1888–1909), including its isoseismal maps, as well as descriptive catalogs of Mexican earthquakes before 1888; annual catalogs (1889–1912); contemporary seismicity maps (1858–1927); and earthquake questionnaires (1863–1904) have been deposited in the Open Science Framework (OSF) storage, whereas the early Mexican station bulletins (1909–1934) have been contributed to the Electronic Archive of Printed Station/Network Bulletins recently created by the International Seismological Centre. They will be of value in modern studies of historical earthquakes and to historians of earthquake science.