# SISMOMex The Servicio Sismológico Nacional (SSN, National Seismological Service of Mexico) was officially founded in 1910, 6 years after the first recorded paper seismogram in Mexico. The network grew up to 12 stations by the end of the 1920s. The network was augmented and instrumentation updated beginning in the late 1960s. Paper seismograms exist for some stations until 2015 with one station at the Institute of Geophysics of Universidad Nacional Autónoma de México (UNAM) still recording on paper. The SISMOMex project is hosted by Joint Earth Science Library (Biblioteca Conjunta de Ciencias de la Tierra [BCCT]), UNAM. The project represents more than 110 yrs of seismological information from Mexico. Its objective is the preservation, search, recovery, systematization, reuse, and dissemination of data and information from the seismograms generated by the SSN and published material about earthquakes and seismology in Mexico. The project aims to digitize the historical seismograms that contain the most important earthquakes nationally and worldwide, as well as the 15,000 oldest seismograms in the collection. [SSSN website](http://www.sismoteca.unam.mx/) ## Stations Stations installed prior to 1922. **Location** | **Code** | **Latitude** | **Longitude** | **Timespan** | **Components** :--- | :---: | :---: | :---: | :---: | :---: Tacubaya | TAC | 19.405 | -99.194 | 1910 | 3 Mazatlán | MAZ | 23.188 | -106.406 | 1910 | 3 Oaxaca | OAX | 17.021 | -96.763 | 1911 | 3 Mérida | MER | 20.948 | -89.616 | 1912 | 3 Zacatecas | ZACM | 22.776 | -102.549 | 1912 | 3 Guadalajara | GUM | 20.679 | -103.341 | 1920 | 3 Colima | COLM | 18.196 | -103.704 | 1920 | 3 Puebla | PUE | 19.042 | -98.197 | 1920 | 3 Veracruz | VCM | 19.201 | -96.138 | 1920 | 3 Manzanillo | MNZ | 19.054 | -104.331 | 1920 | 3 Chihuahua | CHH | 28.637 | -106.078 | 1922 | 3 Other stations not listed here are available online. ## Instrumentation Early instruments: * Wiechert * Bosch-Omori * Milne Late 1960s: * Electromagnetic vertical short-period See also Suter (2025). ## Recording Medium paper ## Data Availability 310,000 paper seismograms are stored with Biblioteca Conjunta de Ciencias de la Tierra, UNAM. The catalog of records with the link to images of seismograms generated in Mexico from the 1900s to date can be accessed online. [[search database](http://132.248.182.16:8991/F/-/?func=find-b-0&local_base=ati01)] BROKEN LINK 2025-08-12 **no. available** | **format** | **dpi** | **color** | :---: | :---: | :---: | :---: 18,000 | jpg| 300 dpi | grayscale Seismograms not found in the database can also be requested by email: SSNdata@sismologico.unam.mx See the SSN [website](http://www.sismoteca.unam.mx/) to download data and for more information on data availability. The project has also developed TIITBA a new portable open-source multi-platform graphical user interface (GUI) coded on Python3, specifically developed for the vectorization, analysis and correction of legacy smoked paper seismograms. The software also includes modules to produce output files for SEISAN analysis. (*add reference*) ## Contact ## Acknowledgements Programa de Apoyo Financiero para el Desarrollo y Fortalecimiento de los Proyectos Unitarios de Toda la Universidad Nacional Autónoma de México (UNAM) en Línea (PAPROTUL), Project TUL_1380. ## References Max Suter; Early Macroseismic Intensity Observations, Isoseismal Maps, and Instrumental Recordings of Earthquakes in Mexico (1888–1934): A Review. Seismological Research Letters 2025; doi: https://doi.org/10.1785/0220250157 Xyoli Pérez‐Campos, Saul Armendáriz‐Sánchez, Víctor H. Espíndola, Minerva Castro‐Escamilla, Jesus Perez, Luis Manuel Casiano, Ivan Rodriguez Rasilla, Caridad Cárdenas Monroy, Arturo Cárdenas (2020). Preservation and Reuse of Historical Seismic Data in Mexico: SISMOMex and the Online “National Seismogram Library”. Seismological Research Letters; 91 (3): 1482–1487. doi: https://doi.org/10.1785/0220190340 Sismoteca Nacional en Linea, Universidad Nacional Autonama de Mexico, http://www.sismoteca.unam.mx/base/. *Last accessed 4 January 2022.*