GEM Global Active Faults Database
Quick answer: The GEM Global Active Faults Database provides 13,696 active fault traces with slip rate and type data for seismic hazard assessment, hosted here as a 5.6 MB web-ready GeoJSON with a live map and slip-type summary.
About this dataset
13,696 active fault traces from the GEM Foundation with slip type and slip rate — hosted as a 5.6 MB GeoJSON with an instant map and summary.
The GEM Global Active Faults Database is a comprehensive compilation of active tectonic fault traces worldwide: 13,696 LineString features with fault name, slip type (normal, reverse, dextral, subduction thrust, spreading ridge), slip rate, dip, and seismogenic depth range. This page hosts a web-ready extract (same traces, trimmed attributes, coordinates rounded to ~11 m) so the map and summary load directly; upstream slip-rate tuples such as "(1.55,0.8,2.22)" are parsed into numeric `slipRate` / `slipRateMin` / `slipRateMax` fields, and the full harmonised release stays on GitHub.
How to download
- 1 Inspect the hosted preview above — the summary groups every trace by slip type.
- 2 Download the hosted GeoJSON when you need fault traces for web mapping.
- 3 For the complete attribute set (rake, references, catalogue IDs) grab the harmonised release from GitHub.
- 4 Overlay faults with the USGS 30-day earthquake layer for a live seismic picture.
FAQ
What fault attributes are included?
This hosted copy keeps fault name, slip type, net slip rate, dip direction, average dip, and the seismogenic depth window. The GitHub release adds rake, catalog identifiers, and literature references.
Is it better than USGS data?
GEM provides global coverage; USGS offers more detail for the US specifically.
Why do the traces differ slightly from the GitHub file?
Coordinates are rounded to four decimals (~11 m) and unused attributes are dropped so the file fits the site's 10 MB hosting rule. Geometry is not simplified — every one of the 13,696 traces is present.
Does the share-alike licence affect my project?
GEM releases the data under an attribution share-alike licence. Attribute the GEM Foundation, and if you redistribute a modified database, publish it under the same terms.