TY  - Data
T1  - ISC-GEM Global Instrumental Earthquake Catalogue (1904-2021)
A1  - International Seismological Centre
A1  - Global Earthquake Model Foundation
DO  - 10.12072/ncdc.earthquake.db7466.2026
PY  - 2026
DA  - 2026-06-24
PB  - National Cryosphere Desert Data Center
AB  - ISC-GEM is a global catalog of instrumentally-recorded earthquakes led by the International Seismological Center (ISC). Using a consistent ak135 velocity model and relocation algorithm, it recalibrated approximately 74,100 global large earthquakes (Mw≥5.0) between 1904 and 2021-including epicenter locations, source depths and scales of various magnitudes, allowing seismic parameters recorded by different instruments to be compared with each other during different periods. Data format CSV (main catalog + supplementary catalog), KMZ (Google Earth).It should be noted that the lower limit of magnitude changes significantly with time: only ≥7.5 events were included from 1904 to 1917, ≥6.25 events were included from 1918 to 1959, and ≥5.0 were gradually covered after 1960; changes in detection capabilities need to be corrected when making time series statistics. The earthquakes in the supplementary catalog (highly uncertain location or magnitude) are not suitable for fine analysis. The main catalog should be used first. The source depth accuracy of shallow earthquakes is limited and should not be directly used for structural interface interpretation.Core variables:(1) Earthquake occurrence time: UTC time, accuracy varies according to station coverage;(2) Epicenter coordinates: longitude and latitude, repositioned via ak135 model;(3) Focal depth: km, the accuracy of shallow earthquakes is limited by the geometric distribution of stations;(4) Moment magnitude: the main magnitude scale of the Mw catalog, waveform inversion or empirical relationship conversion;(5) Body wave magnitude: the main magnitude scale of mb early events, measured by short-period instruments;(6) Surface wave magnitude: Ms long-period surface wave measurement, V12 has been greatly completed by data from China Network;(7) Focal mechanism solution: strike/dip/slip angle, some large events are available.
DB  - NCDC
UR  - http://www.ncdc.ac.cn/portal/metadata/51bf08f4-b33b-4f44-8ec5-4477609c67e6
ER  -