Seismic Data from the Center for Earthquake Research and Information

New Madrid Catalog

This is a catalog of instrumental locations for earthquakes in the New Madrid Seismic Zone and surrounding regions, 1974 to present. Because the network has evolved over the years, there is no guarantee of consistency in detection threshold, magnitude determination or region covered. The data in this catalog come from numerous sources:

1974-1992: TEIC earthquake bulletin and St Louis Regional Catalog
1993-1994: Saint Louis University and Central Mississippi Valley Earthquake Bulletins
1995-present: earthquakes reported by SLU and/or CERI
2003-present: addition of CERI East TN earthquakes and contributions from the SEUSSN

Output from the catalog search should have the following format:



NET  DATE       O.T. (UTC)     LAT       LONG        DEP    MAG  NPH GAP  DMIN     RMS     SEO     SEH     SEZ    Q COMMENTS

ET   2004/03/13 17:07:57.5300  36.48034  -84.03350   8.8600 2.7   16 132  38.0000  0.1135  0.1000  3.2000  5.1000 C 1.51 km south of Westbourne,TN
SE   2004/03/14 13:39:54.2000  34.36100  -85.51600   9.7000 2.0   15 105 100.0000  0.2000  0.0000  0.5000  1.8000 C
NM   2004/03/14 22:34:36.5400  36.50217  -89.54600   7.2400 1.8   43  58   4.0000  0.0497  0.1000  0.7000  1.6000 B 4.72 km west of Bessie,TN (L,N)


DATE:       Date of earthquake (YYYY/MM/DD)
O.T.:       Origin Time of earthquake (UTC) 
LAT:        Latitude
LON:        Longitude
DEP:        Depth (km)
MAG:        Magnitude
NPH:        Number of phases used
GAP:        Aziumthal gap in station coverage
DMIN:       distance to nearest station (km)
RMS:        average rms error of arrivals (sec)
SEO:        standard error of origin time
SEH:        standard horizontal error (km)
SEZ:        standard vertical error (km)
Q:          Solution Quality
COMMENTS:   Additional comments, including felt information or
            independent magnitude determinations.  Events from
            1995 on include event quality (A=good, D=poor) and
            only report origin times to the nearest second even
            though accuracy may be known to a few tens of milliseconds.
            Epicentral accuracy varies throughout the catalog but
            in no case is better than a few tenths of a kilometer
            (0.01 degrees latitude is about 1.11 km or 0.69 miles).

Magnitudes are Md unless otherwise indicated in the comment field.  
When available, Mw is preferred over Md (approximately low- to mid-magnitude 3).

Note that information does not exist for all field for all events.  If
information is unavailable, then 0 is used.  In some cases depth is fixed
and hence sez is 0.