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)

Another Deadly Earthquake Cluster Hits China

China quake damages more than 100,000 homes, 25 dead

Revised figures in brackets are from a more recent report by AP.

BEIJING, Aug 31 (Reuters) – An earthquake that hit southwest China’s Sichuan and Yunnan provinces has killed [32] people [another 467 people injured], damaged or destroyed more than 258,000 homes and affected at least 600,000 residents [about 152,000 were evacuated,] state media said on Sunday.

Li Fucui, 47, cries in front of the debris of her collapsed house, which buried her brother-in-law, in Huili County, Sichuan Province. (Image: Reuters). Image may be subject to copyright.

The epicenter of Saturday’s quake, which struck around 4:30 p.m. (0730 GMT), was about 20 miles (30 km) southeast of Panzhihua, near Sichuan’s border with Yunnan, according to the U.S. Geological Survey. The quake was about 6 miles (10 km) deep.

The USGS put the magnitude of the quake at 5.7, while China’s official Xinhua news agency said it measured 6.1.

A 5.6-magnitude aftershock hit the same area 24 hours later, the USGS said on Sunday. There were no immediate reports of further damage.

Xinhua said Saturday’s quake had injured more than 250 people, and three more were missing.

It added that 656 schools had also been damaged and that heavy rain and difficult terrain were hampering rescue efforts, with mobile telephone communications patchy.

State television showed pictures of houses with large cracks in their sides, broken tiles on the road and people receiving medical attention under tents.

The government was rushing disaster relief to the affected areas, including thousands of tents and blankets and tonnes of food and water, Xinhua said.

Parts of Sichuan province were devastated by an earthquake that killed about 70,000 people in May. The province, known for its pandas and fiery cuisine, has struggled to rebuild after the disaster, which left 10 million people homeless. (Reporting by Ben Blanchard; Editing by Alex Richardson)

China should prepare for another massive earthquake in the Sichuan and Yunnan border area this winter!

Latest From TAAL and other Philippines Volcanoes

As per FEWW Forecast, Taal Volcano has begun seismic unrest significantly increasing the probability of  explosive eruptions

Taal Volcano Advisory

From: Philippines Institute of Volcanology and Seismology

28 August 2008 –  4:00 P.M.

This is to notify the public and concerned authorities on the ongoing seismic unrest at Taal Volcano.

The Taal seismic network recorded ten (10) volcanic earthquakes from 5:30 A.M. to 3:00 P.M. today. Two (2) of these quakes that occurred at 12:33 and 12:46 P.M. were both felt at intensity II by residents at barangay Pira-piraso. These quakes were accompanied by rumbling sounds. The events were located northeast of the volcano island near Daang Kastila area with depths of approximately 0.6km (12:33 P.M.) and 0.8km (12:46 P.M.)

Taal Volcano Seen through Lake Taal (Photo: Jhun Taboga)

A cinder cone in an acidic lake on Taal Volcano (Credit: JG Moore of the US Geological Survey)

Surface thermal observations however, did not indicate significant change in the thermal and steam manifestations of the Main Crater Lake area.

The increase in seismicity at Taal Volcano reflects a low-level episode of unrest. Alert Level 1 remains in effect over Taal Volcano. At present, no imminent eruption is indicated although the public is advised to observe some precautions. In this regard, PHIVOLCS reminds the general public that the Main Crater area is off-limits because steam explosions may suddenly occur. Other hazards within the Main Crater may be the build up of toxic gases in case of more pronounced volcanic reactivation. The northern portion of the Main Crater rim, in the vicinity of Daang Kastila Trail, may also be hazardous, when reactivated with steam emission and increased thermal activity. Furthermore, the public is reminded that Taal Volcano Island is a high-risk area and permanent danger zone, hence, habitation is strictly not recommended.

Related Links:

• Philippines Taal Volcano Could Erupt Anytime!

Mayon Volcano Advisory

August 10, 2008 – 12:00 P.M.

At 9:12 A.M. today, Mayon Volcano manifested mild ash explosion that reached an approximate height of 200 m above the summit crater before drifting east-northeast. The ash-ejection was recorded as explosion-type earthquake which lasted for one minute by the seismic network deployed around the volcano.Immediately after the explosion, visual observation becomes hampered by the thick clouds. During the past weeks, seismic activity had slightly increased and crater glow had slightly intensified. Precise leveling surveys conducted at Mayon from May 10 – 22, 2008 compared to February 17 – March 2, 2008 survey also showed inflation of the volcanic edifice.

The above observations show that Mayon Volcano is undergoing an episode of increased activity probably related to magma movement and post eruptive behavior of the volcano. Although no major eruption is indicated, steam and ash explosions may occur in the following days.

In view of the above, PHIVOLCS reiterates that Mayon Volcano’s status remains at Alert Level 1. The public, however, is reminded that the 7-km Extended Danger Zone (EDZ) at the southeastern flank of the volcano and the 6-km radius Permanent Danger Zone (PDZ) at other areas remain off-limits due to the continuing threat from sudden small explosions and rockfalls from the upper slopes. Active river channels and those areas perennially identified as lahar-prone around the volcano should be avoided when there is heavy and prolonged rainfall. PHIVOLCS is keeping a tight watch over Mayon and shall immediately report any significant development to all concerned.

Related Links:

• Mayon Volcano Ejects Ash