Revised information on the previous earthquake that was reported as a 6.0 at 1331, upgraded to 6.2 according to USGS; however, Kyodo reports it as 6.4.
http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc00023fx.php
Earthquake Details
This event has been reviewed by a seismologist.
Magnitude
6.2
Date-Time
Tuesday, March 15, 2011 at 13:31:46 UTC
Tuesday, March 15, 2011 at 10:31:46 PM at epicenter
Time of Earthquake in other Time Zones
Location
35.300°N, 138.700°E
Depth
10 km (6.2 miles) set by location program
Region
EASTERN HONSHU, JAPAN
Distances
36 km (22 miles) S of Kofu, Honshu, Japan
37 km (22 miles) NW of Numazu, Honshu, Japan
42 km (26 miles) NNE of Shizuoka, Honshu, Japan
116 km (72 miles) WSW of TOKYO, Japan
Location Uncertainty
horizontal +/- 12.1 km (7.5 miles); depth fixed by location program
Parameters
NST=358, Nph=379, Dmin=135.8 km, Rmss=0.79 sec, Gp= 40°,
M-type=centroid moment magnitude (Mw), Version=D
Source
USGS NEIC (WDCS-D)
Event ID
usc00023fx
M6.4 quake jolts Shizuoka, vicinity
http://english.kyodonews.jp/news/2011/03/78331.html