Landform in quake zone shows changes

Landform in quake zone shows changes - scientists

(Xinhua)
Updated: 2008-09-04 06:34

BEIJING -- The landform in the areas hit by the 8.0-magnitude May 12 earthquake in southwest China notably changed, but outlying regions were little affected, the State Bureau of Surveying and Mapping (SBSM) said here on Wednesday.

The SBSM finished a two-month survey of landform changes in the quake area jointly with the China Earthquake Administration (CEA) in mid-July.

The monitoring point of the Earth's surface in the epicenter levelly moved 238 cm. The surface sank by a maximum 70 cm and heaved up by 30 cm, said Li Weisen, the SBSM vice director, at a press conference.

The plate, west of the fault zone along the Longmen Mountain where the epicenter was located, moved southeast by 20 to 70 cm while the plate east of it moved northwest by 20 to 238 cm and sank by 30 to 70 cm, he said.

The movements of neighboring plates were small. The plate in south Shaanxi Province, neighboring Sichuan Province, moved northwest by 4 cm and the southern part of Gansu Province moved northeast by 5 cm.

As the powerful earthquake was caused by a crash between the Indian Ocean Plate and Euro-Asia Plate, the authority also surveyed the area around Mt. Qomolangma (Everest), Li said, adding that it moved southwest by 2 to 3 cm.

About 100 experts were sent to survey the 180 global positioning system monitoring points in the quake areas and neighboring regions.

"As the landform was changed by the quake, the Earth coordinates of the region also changed. The survey identified new coordinates and they will be useful in rebuilding," said Yin Chaomin, CEA deputy director.