According to the USGS site, this is the location of Korea's nuclear test that occured Monday, October 9, 2006 at 01:35:27 (UTC). It is about 2 miles NE of the P'unggye-yok Test Site (marked by another goodle earth user). Earthquake details (from USGS) :
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/ustqab.php
Earthquake Details
Magnitude 4.2 (Light)
Date-Time Monday, October 9, 2006 at 01:35:27 (UTC)
= Coordinated Universal Time
Monday, October 9, 2006 at 10:35:27 AM
= local time at epicenter Time of Earthquake in other Time Zones
Location 41.311°N, 129.114°E
Depth 0 km (~0 mile) set by location program
Region NORTH KOREA
Distances 70 km (45 miles) N of Kimchaek, North Korea
90 km (55 miles) SW of Chongjin, North Korea
180 km (110 miles) S of Yanji, Jilin, China
385 km (240 miles) NE of PYONGYANG, North Korea
Location Uncertainty horizontal /- 14.9 km (9.3 miles); depth fixed by location program
Parameters Nst= 9, Nph= 9, Dmin=369.4 km, Rmss=1.13 sec, Gp= 97°,
M-type=body magnitude (Mb), Version=6
Source USGS NEIC (WDCS-D)