Since its foundation in 1904, l'Observatori de l'Ebre (OE) has operated, virtually uninterruptedly, different seismographs, being the oldest seismic station in Catalonia. Throughout the years more than 20 seismographs have been in operation. From the first Grablovitz, which was installed in 1904, to the last Wielandt-Strecksein STS-2 with a 24-Bit Quanterra Q680-LV digitizer, a large number of records have been accumulated, mostly on paper (the first in smoked paper, then photo paper, ink and thermal paper) and the most modern ones in digital format.

It took a great effort for the conservation and dissemination of this valuable and voluminous heritage, more than 100,000 seismograms, which the OE could not address by itself. It is with this intention, among others, that in June 2016 a collaboration agreement was signed between the OE and the Institut Cartogràfic i Geològic de Catalunya (ICGC), which is the dependent entity of the Department of Territory and Sustainability with competences on seismology and cartography, through which the scanning of the OE seismograms was started. This agreement has been renewed in 2017 and 2018 and has allowed the digitization of some series of seismograms, as well as the modernization of the OE seismic station.

The digitized seismograms can be visualized by selecting the name of the instrument in the following table, which in turn shows the different instrumentation that has been operating over the years in the OE. The links will lead you to ICGC pages, where the different seismograms are housed and where the conditions of use and the appointment of the sources are reported.

Instrument  Years Type

Period

(s)

Components

Mass

(kg)

Recording 

rvelocity

(mm/minute)

Amplificaction
Grablovitz 1904-1918 M 13 NE-SW/NW-SE 12 5 8
Vicentini Vertical 1904-1936 M 13 Z 50 15 150
Microsismògraf Vicentini 1904-1916 M 0.85 N-S 100 15 90
1904-1928 M 2.3 E-W 100 15 90
Mainka Ebre 1914-1941 M 14.8 N-S 1501 12 200
Mainka Ebre 1914-1938 M 7.8 E-W 157 12 110
Pèndol verical Ebre 1914-1915 M (2.5) NE-SW/NW-SE 316 12  
Pèndol verical Ebre 1915-1941 M 2.6 N-S 316 12  125
Mainka Ebre 1942-1966 M 15.4 N-S 1500 12 275
Mainka Ebre 1942-1966 M 10.8 E-W 1500 12 150
Pèndol verical 1943-1961 M 2.5 N-S 635 12 230
Pèndol zenital 1961-1966 M   Z 635 12  
Geotech 4681A 1966-1974 E 15 Z 15 60 50000
Geotech6102A 1966-1974 E 15 N-S 15 60 50000
Geotech6102A 1966-1974 E 15 E-W 15 60 50000
Sprengnether S-5000V  1969-1974   E 1.0 11.2  15  1500
Sprengnether S-5000H  1968-2000 E 1.0 N-S 10.7 15 1500
Sprengnether S-5000H 1968-2000 E 1.0 E-W 10.7 15 1500
Sprengnether S-5000V  1974-2000 E 1.0 Z 11.2 15 1500
SS-1 Ranger EROQ 1987-2003 E 1.0 Z 1.45 60  
SS-1 Ranger EROQ 1991-2003 E 1.0 N-S 1.45 60  
SS-1 Ranger EROQ 1991-2003 E 1.0 E-W 1.45 60  

 

Table adapted form  Batlló & Ugalde, 2000 (Els sismografs de l'Observatori de l'Ebre. Actes de les V Trobades d'Història de la Ciència i de la Tècnica, Barcelona, Spain, 161-165). Type: M mechanical, E electromagnetic.