Modern tech helps prevent geological risks in China's Three Gorges region

WUHAN, Aug. 31 (Xinhua) -- Integrated modern technology is helping geologists "tame" the treacherous rock formations of the mountainous Three Gorges Reservoir region, bolstering efforts to prevent and mitigate geological disasters.

Thanks to years of efforts in field investigation and technological exploration, the Wuhan Center of China Geological Survey has established interrelated means to fend off geological disasters in this region, according to Li Ming, a senior engineer at the center.

These technological means include a multi-dimensional rock monitoring system, an integrated information platform for geological hazard prevention and control, as well as a series of ecological restoration techniques for dangerous rock masses.

The Three Gorges project is a vast multi-functional water-control system on the Yangtze River, China's longest waterway.

The Three Gorges Reservoir region is characterized by steep mountains, precipitous slopes, and complex rock formations, making it one of the areas in China most prone to geological disasters. So far, more than 3,000 potential hazard sites have been identified.

To cope with the potential hazards, the center has established an information platform for geological hazard prevention and control, integrating multi-source data including geological base maps, disaster registries and monitoring and early-warning information, Li said.

He noted that one deep rock crevice in Zigui County, central China's Hubei Province, extends more than 110 meters deep. Over 50 crevices cut through the mountain massif, forming an unstable rock body with a total volume exceeding 3 million cubic meters.

The engineer further explained that the upper section of the dangerous rocks consists of hard rock, while its lower section comprises relatively soft coal-bearing strata. The unstable rock body sits right next to the main navigation channel of the Yangtze River.

"Should it collapse and plunge into the river, the surge wave generated instantaneously would pose a severe threat to the safety of passing vessels," Li said, adding this dangerous rock mass is currently stable thanks to multiple engineering measures.

Various devices installed on the cliff face are providing round-the-clock precise monitoring of subtle deformations in the rock mass, summarizing data once every hour and uploading it in real time for monitoring and early warning, Li said.

To address the challenge of dangerous rock masses in the reservoir area, the center has developed a specialized technology by fixing such rock masses with lightweight anchor cable and explored an ecological restoration technique for rock crevices using microorganisms combined with fiber filling, according to Dai Zhenwei, who takes charge of the center's geological disaster monitoring and early warning.

The technological explorations are similar to putting a "safety belt" on the unstable rocks. They provide a new approach to solving the challenge of poor durability of traditional protective structures in water-rich environments, Dai said.

In the meantime, drones and diverse satellite monitoring devices have been put into service to conduct the round-the-clock monitoring works to assess the stability conditions affected by the fluctuations in reservoir water levels, according to Huang Jue, a senior engineer at the Wuhan center.

Huang explained that traditional manual inspections normally take a long period of time and costs are high. The drones can fly close to steep cliffs, dangerous rocks and other areas that are difficult for people to reach.

"Moreover, drones can take off immediately when traffic is disrupted after disasters occur and provide first-hand information for rescue decision-making in a timely manner," he added.