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National Seismic Hazard Model (NSHM) Earthquake Catalogs

With each release of the NSHM, a variety of earthquake catalogs are compiled and subsequently processed to remove duplicate, dependent (foreshocks and aftershocks), and anthropogenic events. Gridded seismicity source models in hazard calculations are derived from final, filtered catalogs. The tables below outline the processing steps applied to each catalog available in this repository.

2014 NSHM Catalogs

Details of the earthquake catalogs used in constructing the 2014 NSHM, by file. For 2014, anthropogenic events are classified as mining-related and/or explosions (M&E), or potentially fluid induced (PFI). Declustered catalogs (dependent events removed) only include M ≥ 2.5 events.

Name	Region	Duplicate	Dependent	Anthro. M&E	Anthro. PFI
2014_emm.c2	CEUS	❌	✅	❌	✅
2014_emm.c3	CEUS	❌	❌	❌	✅
2014_emm.c4	CEUS	❌	❌	❌	❌
2014_wmm.c2	WUS	❌	✅	❌	✅
2014_wmm.c3	WUS	❌	❌	❌	✅
2014_wmm.c4	WUS	❌	❌	❌	❌

✅ = events included
❌ = events deleted
WUS = Western US
CEUS = Central & Eastern US

2008 NSHM Catalogs

Details of the earthquake catalogs used in constructing the 2008 NSHM, by file.

Name	Region	Duplicates	Aftershocks	Anthropogenic	Notes
emb.c_nd	CEUS	❌	✅	✅	1
emb.cc	CEUS	❌	❌	❌	2
wmm.c_nd	WUS	❌	✅	✅	1
wmm.cc	WUS	❌	❌	❌	3

✅ = events included
❌ = events deleted
WUS = Western US
CEUS = Central & Eastern US

1 = Explosion and mining related events included
2 = mbLg ≥ 3
3 = Mw ≥ 4