I got a few notices about it then this one:
DELETED: Event NM hwb0418a
== EVENT DELETED NOTIFICATION ==
***This event has been deleted after review by a seismologist.***
Geographic coordinates: 38.450N, 87.890W
Magnitude: 5.2
Universal Time (UTC): 18 Apr 2008 09:36:59
Time near the Epicenter: 18 Apr 2008 03:36:59
Location with respect to nearby cities:
7 km (5 miles) NNE (13 degrees) of Bellmont, IL
9 km (6 miles) E (88 degrees) of Bone Gap, IL
11 km (7 miles) N (350 degrees) of Keensburg, IL
60 km (38 miles) NNW (331 degrees) of Evansville, IN
206 km (128 miles) E (95 degrees) of St. Louis, MO
...so either you guys are imagining things, or maybe it was something other than siesmic activity..??