Ring of Fire

The problem

One file, the whole world, and three surprises

USGS publishes the past seven days of earthquakes as a single GeoJSON file, and a browser can read it directly. The hard part is what is inside it: events that are not earthquakes, magnitudes measured on different scales, and a large share of events that are first drafts and can still change or disappear.

Watch it work

Episode 5 — Ring of Fire (5:47)

Two public feeds end to end: where the earthquake and volcano data live, the three details that cost the most time, and the map they turn into.

What it covers

Two feeds, three details, one map

• The feeds: one request to the USGS all_week GeoJSON summary returns the whole world — about 1.5 MB on the day the episode was recorded — with open headers and a cache of about a minute. The USGS Volcano API lists the US volcanoes at an elevated alert level; on the recording day there were four. Ring of Fire refreshes both every five minutes.
• Detail one, not every event is an earthquake: the same file carries quarry blasts and explosions — 27 and 13 in the week shown. Ring of Fire keeps the earthquakes and says how many it left out.
• Detail two, magnitude is not one scale: the feed mixes local, duration, body-wave and moment magnitudes. Ring of Fire shows the number the network published and never averages across scales. It also keeps the magnitudes below zero and the depths above the reference level, because both are real readings.
• Detail three, many events are first drafts: of about 2,100 events, 637 were automatic solutions that can be revised or deleted. Ring of Fire re-reads the whole file rather than patching what it already has.
• How it becomes a map: every quake is a circle sized by magnitude and colored by depth over the plate boundaries, the newest carry a halo, magnitude and time-window filters restyle the map at once, the list ranks events by the feed’s own significance value, and a 3D view draws each quake at its depth below the surface.

What it does not do

• No history beyond a week — Ring of Fire shows the USGS past-seven-days feed, not the earthquake catalog.
• No blasts or explosions on the map — they are counted, not drawn.
• Not an earthquake warning or alert service — it shows public USGS readings that can be revised. For safety decisions, follow your local emergency management agency.

Where the data comes from

Every source in the episode

• USGS earthquake GeoJSON summary feeds — earthquake.usgs.gov/earthquakes/feed/v1.0/geojson.php
• USGS ComCat event terms (event type, magnitude type, review status) — earthquake.usgs.gov/data/comcat/data-eventterms.php
• USGS Volcano API — volcanoes.usgs.gov/vsc/api/volcanoApi/
• Plate boundaries: Bird (2003) PB2002, via Hugo Ahlenius / Nordpil (ODC-By 1.0) — github.com/fraxen/tectonicplates
• Global Volcanism Program, Smithsonian Institution — volcano.si.edu/
• USGS: acknowledging or crediting USGS — usgs.gov/information-policies-and-instructions/acknowledging-or-crediting-usgs
• Source sheet with every endpoint — allthingsspatial.io/pages/sources.html

USGS earthquake and volcano data are in the public domain, as works of the United States government, and USGS asks to be credited. The plate boundaries are published under an open attribution license, and the volcano list is credited to the Smithsonian’s Global Volcanism Program. All three credits sit in the Ring of Fire footer and its About dialog.