Seismic Stations
The instruments that hear the Earth. TerraPulse holds one slot per permanent
seismic-network station in the seismic_station Locationdex — where it is, who
registered it, when it operated, and which classes of instrument it has carried.
This is a registry layer, and it is careful about what that means: a station slot says an instrument is at a place. It asserts no reading. The measurements those instruments produced live in the event dexes, not here.
The dex
| Dex | Holds | Stations |
|---|---|---|
seismic_station | One permanent seismic-network station: network, code, position, elevation, operating span, instrument classes | 15,966 |
Operating spans run from 1901 to 2026. 7,210 of the stations are retired — a station that stopped recording is still a real place that recorded, and it keeps its slot.
What each station carries
Beyond identity and position, each slot records the instrument classes registered on the station across its whole history — seismometers on 11,551 of them, accelerometers on 6,466, and a long tail of co-located instruments: infrasound pressure sensors, magnetometers, gravimeters, strainmeters, tiltmeters, tide sensors, and weather sensors. 823 stations carry no seismic sensor at all, which the slot states rather than hides.
453 slots fold more than one network registration into a single station, because one physical station registered by two networks is one place. 58 carry a revised position from the operator.
The same place in two lists
Sixteen of these stations are the same installation as an observatory in the
magnetic_observatory dex — most of them run by the USGS Geomagnetism Program, which
appears in both the INTERMAGNET observatory registry and the FDSN station registry. Both
lists keep the site, each citing its own source. A dex is one network's roster of the
places it instruments, and a site that two networks instrument genuinely belongs to both.
Provenance
Every slot traces to the NSF SAGE Facility FDSN station service, operated by EarthScope Consortium, retrieved 2026-07-28. Individual network operators must be cited by network code; each slot carries its network DOI where the operator published one — 14,790 of them do.
Temporary deployments, synthetic-seismogram pseudo-stations, and relocatable consumer units are excluded by the dex's frozen scope, along with state-of-health channels. What remains is permanent instrumented places.