On June 6, the reporter learned from the municipal headquarters that preliminary progress has been made in the investigation of the causes of local land subsidence in Balitai Town, Jinnan District. The reporter interviewed relevant experts of the expert group on the causes of land subsidence that are of social concern.

Q: Local land subsidence in Balitai Town occurred relatively suddenly. In the past few days, you and the research team have been carrying out professional monitoring on site, closely analyzing and judging, and guiding the disposal work. Could you please tell us about the reason for this incident?

A: This situation is very rare, in order to find out the reason, the Tianjin Municipal Party Committee and Municipal Government invited more than 20 experts from the Ministry of Natural Resources, the Ministry of Housing and Urban-Rural Development, the Ministry of Emergency Management and other departments to Tianjin to guide the work; In addition, more than 10 professional teams from Beijing, Shanghai, Hebei and Tianjin such as survey, mapping, monitoring, housing appraisal and architectural design carried out monitoring work on site. Based on the various information currently available, we preliminarily judge that this incident is a sudden geological disaster. The objective reason is that the deep geological structure is relatively complex, according to the national scientific research institutions through a variety of advanced means of detection, it is inferred that there is a suspected geological cavity below 1300 meters depth, which is not detectable by conventional survey means. It cannot be ruled out that the construction of geothermal wells touched deep geological structures, resulting in shallow soil erosion and land subsidence in the area involved.

Q: What is the extent of the impact of this land subsidence? What are the current trends?

A: From May 5 to June 31, the initial development of land subsidence was relatively fast, and the high-rise buildings facing the street were affected to varying degrees, and through a series of measures such as grouting and so on, the settlement of ground and buildings has slowed down significantly. After consultation with experts from relevant national departments, we believe that it is currently in a balanced recovery period, and although there are still a few changes, it is generally controllable.

Q: We have noticed that the analysis of the causes of land subsidence you mentioned is still the result of a phased study and judgment. What further steps will the expert group take next?

A: We will strengthen ground and building monitoring to avoid secondary disasters. We also need to mobilize scientific and technological forces, use geophysical methods and other technical means, to further explore and evaluate the deep geological structure of the formation, so as to study and formulate the next disposal plan.

(Jinyun News reporter Ma Yangyang)