USGS Earthquake Monitor & Catalog Search

Unofficial. Not affiliated with or endorsed by the U.S. Geological Survey (USGS) or the U.S. Department of the Interior. Data comes from the official USGS Earthquake Catalog API (ANSS Comprehensive Catalog, ComCat). USGS-authored data is in the U.S. Public Domain (USGS copyrights and credits). Credit: U.S. Geological Survey.

Search earthquakes worldwide by magnitude, time, region (circle or bounding box), depth, USGS PAGER alert level and review status. Put it on a schedule with Only new or changed since last run to get just new events, plus events USGS has since revised.

What you get

One row per event (eventId), newest first: magnitude and type, place, time (UTC), latitude, longitude, depth, event type, review status (automatic / reviewed), PAGER alert level, tsunami flag, significance, felt-report count, CDI/MMI intensity, network, all catalog ids, station/gap/rms quality values, USGS event page and detail links. Rows also carry updateType (new / changed in monitor mode, otherwise null) and changeHash. compact output keeps the key fields, including updateType and changeHash.

Input

Field	Notes
minMagnitude / maxMagnitude	e.g. 4.5. Empty = any magnitude (many tiny events)
startTime / endTime	UTC, YYYY-MM-DD or ISO date-time. If both are empty, the last 7 days are used
latitude + longitude + maxRadiusKm	circle search
min/max latitude and longitude	bounding-box search (not together with a circle)
minDepthKm / maxDepthKm	depth filter
alertLevel	PAGER green, yellow, orange or red
reviewStatus	any, automatic or reviewed
earthquakesOnly	default true (excludes quarry blasts, explosions, etc.)
maxItems	rows per run, default 25, max 5000
onlyNewSinceLastRun, lookbackDays	monitor mode, see below
outputFormat	full or compact

Example: M4.5+ within 300 km of Los Angeles, only new or revised:

{ "minMagnitude": 4.5, "latitude": 34.05, "longitude": -118.25, "maxRadiusKm": 300, "onlyNewSinceLastRun": true }

Only new or changed since last run

The first run with a set of filters is a baseline: normal results, then a watermark is saved in a named key-value store in your Apify account (usgs-earthquake-monitor-state). Later runs with the same filters ask USGS only for events updated since the previous complete run, within lookbackDays (default 7) of the newest event delivered, and return:

• new: events not delivered before;
• changed: delivered events whose magnitude (to 0.1), magnitude type, review status, PAGER alert, tsunami flag, event type, location (to 0.01°) or depth (to 1 km) was revised.

Updates that touch only other fields (for example felt-report counts) are not re-sent. Revisions to events older than the lookback window are not re-sent. Changed rows are charged like any other row. If a run is cut short (maxItems or your cost limit), the rest arrive on the next run. If a baseline run is cut short, older matching events are not delivered later; run once without monitor mode to get them.

Run summary

The OUTPUT record has count, chargedCount, the USGS request URL, returnedByApi, truncated (true only when more matching rows exist beyond maxItems or the cost limit, including on a cut-short monitor baseline, where olderMatchesSkipped is also true), monitor details (newCount and changedCount, counted from pushed rows, plus skippedUnchanged, the watermark and the cursor) and request stats.

Limits and notes

• One USGS request per run in normal use. The Actor waits at least 250 ms between requests (retries included) and makes at most 20 per run. USGS returns at most 20,000 events per query; narrow the time or magnitude range for larger pulls.
• USGS automatic solutions are preliminary and are often revised; reviewed events can still change.
• This is not an early-warning or emergency tool. Do not use it for life-safety decisions; use official USGS/NOAA warnings.
• Deleted events are not reported: USGS omits deleted events from these queries, so an event that USGS later deletes simply stops appearing (no "deleted" row is sent).
• USGS sometimes re-associates an event under a new preferred id. In monitor mode that event shows up as a new row with the new eventId; its allIds list includes the older id(s), so you can match it to the earlier row.
• The catalog includes events contributed by ANSS regional networks and other contributors through USGS ComCat.

Support

Questions or problems: digitalpromohub.support@gmail.com