Powerful Quake, Strong Aftershocks Hit China’s W. Xizang

Earthquake UPDATE

USGS has reported an earthquake cluster striking Western Xizang area. The 6.7 Mainshock which struck about 225 km (140 miles) NE of Jumla, Nepal on August 25, 2008, was followed by at least five powerful aftershocks measuring magnitude 5 or higher.

A Note of Interest

The mainshock, which struck the area on August 25 at 09:21:59 PM (time at epicenter), was located at 30.893°N, 83.614°E. Those coordinates put the epicenter in the eastern section of Palung Co lake in  the western Xizang province, Tibet Autonomous Region (China).

An examination of the images of Palung Co reveals that the lake, especially its southern section formation, is a large caldera formed either by multiple caldera collapse events or by a large lateral sector collapse. See Google Earth [30° 49’N, 83° 34’E] for visual confirmation.

The discovery gives rise to a number of interesting questions including the date for last eruption in the-now-sunken calderas, and the probability of renewed volcanic eruptions occurring as a result of the powerful seismic activity in the area.

Images: USGS

Quake Magnitude: 6.7
Date & Time:

• Monday, August 25, 2008 at 13:21:59 UTC
• Monday, August 25, 2008 at 09:21:59 PM at epicenter

Location: 30.893°N, 83.614°E
Depth: 12 km (7.5 miles) set by location program
Region: WESTERN XIZANG
Distances:

• 225 km (140 miles) NE of Jumla, Nepal
• 295 km (185 miles) N of Pokhara, Nepal
• 370 km (230 miles) NNE of Nepalganj, Nepal
• 390 km (245 miles) NNW of KATHMANDU, Nepal

Location Uncertainty: horizontal +/- 7.9 km (4.9 miles); depth fixed by location program (Source of data: USGS)