IMHE expert team, headed by Researcher Cuipeng went to the meizoseismal areas (Luyang Town, Longmen Town, Baosheng Town) by walking and carried out disaster data cataloging, field measurements, and evaluated the impact to disaster relief work on April 22, 2013.
Experts found that the collapse was the main secondary disaster of Lushan earthquake. The collapse was mainly developed in steep slope and cliffs of Mesozoic sand and mudstone interbed and Tertiary conglomerate. The collapse was controlled by the layers and joint surfaces, and fell down while the earthquake took place.
Experts in quake zone. (picture by IMHE)
The regional tectonic background is a controlling factor of secondary geo-hazard in Lushan earthquake. The secondary geo-hazard mainly distributed in belt near the canyon and epicenter. Although the scale of most collapse disasters are small, but they occurred frequently near the canyon, which greatly hindered relief work. Many roads were cut off. The road from Longmen Town to Baosheng Town was opened till the evening of April 22.
The collapse and rock falls happen frequently during aftershock and bring about great damage to peoples′ life and property. IMHE experts remind people in those regions to take precautions against rock falls and collapse, and avoid casualty and alleviate economy losses.