# usgs-earthquakes — licence and redistribution status

STATUS: this file documents a licence, not a measurement. Nothing in this
benchmark has been measured yet (see the top-level README.md).

## Source

U.S. Geological Survey (USGS) Earthquake Catalog (ComCat), served by the FDSN
`ws-event` CSV service:

> https://earthquake.usgs.gov/fdsnws/event/1/query?format=csv&starttime=2026-09-01&endtime=2026-09-08&minmagnitude=2.5&orderby=time-asc

Pinned to a fixed historical window so the snapshot is reproducible; the
committed `usgs-earthquakes.csv` (sha256 in `../PROVENANCE`) is the canonical
copy the gold-derivation script reads.

## Licence — public domain, quoted verbatim

From the USGS "Acknowledging or Crediting USGS" page, fetched live from this
sandbox on 2026-09-29 (UTC, sandbox clock):

> "Most U.S. Geological Survey (USGS) information resides in the Public Domain
> and may be used without restriction. When using information from USGS
> information products, publications, or websites, we ask that proper credit be
> given."

Page: https://www.usgs.gov/information-policies-and-instructions/acknowledging-or-crediting-usgs

Credit given here as requested: **U.S. Geological Survey**.

## Caveats, stated plainly

- ComCat aggregates events contributed by regional seismic networks (the `net`
  and `locationSource` columns name them). The USGS statement above covers USGS
  information as hosted; this snapshot's events are contributed by public
  networks (`us`, `ak`, `pr`, `tx`, `hv`, `nc`, `ci`, `uu`, ...). No
  contributor-specific restriction was found on the service pages.
- 17 U.S.C. § 105 bars copyright for works of the U.S. Government.
- Redistributed here as a benchmark fixture, unmodified, with credit.
