The key laboratory of neotectonic movement and geological disasters of the Ministry of Land and Resources was formally approved by the Ministry of Land and Resources on September 30, 2007. Its predecessor was the Key Laboratory of Crustal Deformation and Geological Disasters of Chinese Academy of Geological Sciences. The Key Laboratory is mainly engaged in scientific research in five fields: neotectonic movement and its geological hazards and geological environment process research, geostress monitoring technology and geological hazard prediction and evaluation technology research, geostress measurement and its tectonic stress field research in the main active structural zones in Chinese mainland, national major projects, crustal stability and geological environment security research in major cities and important economic zones.
Fig. 46 Technical process of development and application of remote sensing information extraction and monitoring information system for degraded wasteland.
(2) Important scientific research achievements 20 13
1.？ Investigation and Evaluation of Wenchuan Earthquake Geological Disasters was selected as one of the top ten geological scientific and technological advances of the Geological Society.
The project named "Investigation and Evaluation of Wenchuan Earthquake Geological Disasters" in the Top Ten Geological Science and Technology Progress of Geological Society is jointly undertaken by Institute of Geomechanics of Chinese Academy of Geological Sciences and China Geological Environment Monitoring Station. Yin Yueping and Zhang Yongshuang's research team closely focused on major scientific issues and key technologies such as Wenchuan earthquake and geological disasters, and made many innovations in theory, methods and technology, especially integrated innovative ground surveying and mapping, comprehensive geophysical exploration and InSAR technology, and revised the safe avoidance formula for active faults and earthquake fracture zones of thrust engineering in strong earthquake areas; The characteristics of slope vibration monitoring and ground pulsation test are carried out for the first time, and the amplification law of slope vibration is obtained, and the amplification effect of vertical seismic force in canyon area on mountain stability is put forward. Based on the emergency investigation technology of integration of heaven and earth, the rapid mapping and evaluation method after Wenchuan earthquake, the mechanism of earthquake landslide-debris flow disaster and the early identification index of high-level debris flow after earthquake were established, which provided theoretical support for formulating industry standards. The book "Engineering Geology and Geological Disasters of Wenchuan Earthquake" was published by Science Press on the occasion of the 5th anniversary of "5. 12" Wenchuan Earthquake. This book systematically studies the seismic engineering geology and geological disasters in the Wenchuan M8.0 earthquake area, involving key scientific issues such as regional geological structure, seismic engineering geology, monitoring and testing methods of slope vibration, and seismic geological disasters (Figure 47).
Fig. 47 Engineering Geology and Geological Disasters of Wenchuan Earthquake
2. Basic geology and major engineering geological problems along the Trans-Asian Railway from Dali to Ruili, Yunnan.
The project team of "Comprehensive Study on Geological Structure along the Trans-Asian Railway from Dali to Ruili, Yunnan Province" comprehensively planned the project results in time, and compiled and published the monograph "Basic Geology and Main Engineering Geological Problems along the Trans-Asian Railway from Dali to Ruili, Yunnan Province" (Figure 48).
Known as the "Steel Silk Road", the Dali-Ruili Railway (hereinafter referred to as "Darrouy Railway") is about 336 kilometers long, which is the throat project of the Pan-Asian Railway Network connecting Chinese mainland and Southeast Asian countries. However, because the railway needs to cross the southern section of Hengduan Mountains with high hydrological network density, high mountains and deep valleys, bridge and tunnel projects will account for about 70% of the whole line, especially the maximum length and buried depth of tunnel projects greatly exceed the existing railway projects, which is extremely difficult to build. It is urgent to have solid and reliable high-precision basic geological and engineering geological data to support and provide scientific decision-making basis for railway line selection design.
Fig. 48 Basic geology and main engineering geological problems along the Trans-Asian Railway from Dali to Ruili, Yunnan.
In order to actively cooperate with and serve the construction of major national projects, the China-Myanmar international railway channel in southwest China will be opened as soon as possible. Under the careful deployment of the Basic Geology Department of China Geological Survey, the Institute of Geomechanics and Chengdu Geological Survey Center jointly organized and implemented the "Comprehensive Basic Geological Survey from Dali to Ruili, Yunnan Province" project, which timely completed the basic geological survey of 22 maps1.500,000 and the comprehensive basic geological engineering survey of 2k m corridors1.2500,000 on both sides of the railway optimization line. In order to better serve the basic geological work of major national engineering applications, this monograph integrates the latest comprehensive geological survey data along the railway line1:25,000 and the research results of neotectonics and active structures, and comprehensively introduces the engineering geological conditions from Dali to Ruili in the southern section of Hengduan Mountain in western Yunnan, including lithostratigraphy and geological structure, main rock and soil bodies and special lithologic bodies, hydrogeology, geothermal activity, neotectonic movement and active faults, seismic activity, etc. On this basis, the engineering geological environment and characteristics of the main engineering sections along the railway are further summarized, and nine important engineering geological problems are comprehensively analyzed, including: external dynamic geological disasters, engineering geological problems caused by karstification, engineering geological problems of special lithologic bodies (mainly including Permian "broken limestone" and Pliocene "soft rock"), bedding problems, active faults and strong earthquakes, high temperature heat damage and rockburst. In addition, the late Quaternary activities of the main regional active fault zones affecting the crustal stability in this area and their future seismic risks are emphatically analyzed and summarized, and the high seismic intensity areas along the railway with historical strong earthquake data are re-determined. Finally, in view of the surrounding rock stability of the super-long and ultra-deep railway tunnel in Gaoligongshan, combined with the rock mechanics test and analysis data and the in-situ stress measurement results, two-dimensional and three-dimensional numerical simulation studies were carried out respectively, and the surrounding rock stability of the tunnel project was comprehensively evaluated, and the strong rockburst area and the soft rock large deformation area were delineated.
This monograph contains a large amount of information, which closely combines the achievements of basic geological work with engineering application. Therefore, it has important reference value for further understanding the engineering geological environment of Hengduan Mountain area in western Yunnan, and can also play an important reference role for major engineering construction in neighboring areas. Relevant research results can be used as a reference for scientific and technical personnel engaged in regional geology, engineering geology, active faults and seismic geology, geological disasters, numerical simulation and geotechnical engineering.
3. Preliminary progress has been made in the research of landslide disaster prevention technology in major engineering disturbance areas.
20 13 is the second year of the implementation of the national science and technology support project "research and demonstration of landslide prevention technology in major engineering disturbance areas" in the "Twelfth Five-Year Plan", and it is also a key tackling year. The research on key scientific and technological issues, technical methods and demonstration bases has achieved phased results, mainly including the following five aspects: tracking and comparing the progress of landslide prevention at home and abroad, and initially establishing a database framework for catastrophic engineering landslides; Preliminary exploration and research on three key scientific and technological problems of landslide prevention and control: progress has been made in experimental and simulation research on engineering landslide mechanism; Preliminary results have been achieved in the study of key technologies and methods for rapid prevention and control of engineering landslides and the construction of demonstration bases. Relevant research results have been published in the Geological Bulletin in the form of academic papers (Figure 49), and related invention and technology patents are being applied for acceptance.
Fig. 49 "Album of Engineering Landslide Prevention Achievements"
4.？ The development of a new piezomagnetic stress measurement and monitoring system has made important achievements.
Since its implementation in 2008, the project "Experimental Research on Geostress Testing Technology and Method" led by researcher Wu Manlu has been devoted to experimental application research, and has made a series of achievements in the construction of geostress measuring and monitoring stations, research and development of monitoring instruments, patents and personnel training.
In-situ stress measurement and monitoring by piezomagnetic method has always been the characteristic and dominant research direction of geomechanics research institute. The team of "Experimental Research on in-situ stress measurement technology and method" takes piezomagnetic stress measurement and monitoring technology as the main research object, and completes the overall transformation and upgrading of piezomagnetic stress measurement and monitoring instrument structure. At the same time, the developed three-component piezomagnetic stress relief system successfully obtained effective stress data at the hole depth of 2 13m, which is the deepest in-situ stress measurement in the world among similar technical methods. The new four-component piezomagnetic stress monitoring system has been widely used in crustal stability evaluation and active fault monitoring in the southeast margin of Qinghai-Tibet Plateau, Longmenshan fault zone, Zijingguan, Hebei, Capital Circle, Tanlu fault zone and southeast coast. The comprehensive in-situ stress monitoring stations established in relevant areas have successfully captured the stress change information before and after strong earthquakes, enriching the measured stress data and a large number of stress monitoring data.
The data obtained by the new piezomagnetic stress measurement and monitoring system have been published or will be published soon. The wireless piezomagnetic sensor for absolute measurement of deep geostress and the orientation and automatic loading installation system for piezomagnetic sensor for deep geostress monitoring developed by the project have been authorized by two national utility model patents, which provide necessary key technical reserves for China crustal exploration plan.
5. The preliminary results of the study on the seismogenic structure and the characteristics of secondary geological disasters of Lushan earthquake are obtained.
20 13 On April 20th, an earthquake measuring 7.0 on the Richter scale occurred in Lushan County, Sichuan Province. According to the unified arrangement of the Ministry of Land and Resources and the arrangement of the Institute of Geomechanics, the key laboratory completed the emergency investigation of earthquake geology and geological disasters, and published the preliminary research knowledge in the Journal of Geology (English version).
One of the preliminary understandings is the seismogenic structure of the 20 13 Lushan, Sichuan earthquake of magnitude 7 (preliminary study on the seismogenic structure of the Lushan, Sichuan earthquake of magnitude 7.0 on April 20, 2003). Through comprehensive analysis of high-resolution remote sensing image interpretation, distribution of main aftershocks and explanation of focal mechanism, it is considered that the epicenter of Lushan earthquake is located between Taiping Town and Shuangshi Town in Lushan County, with focal depth of 13 ~ 14 km and maximum intensity of IX degree. According to the field investigation, although the buildings in the epicenter area were seriously damaged, the earthquake did not produce obvious surface rupture structure, only a few ground cracks and sand blasting leakage were seen. Lushan earthquake is an independent rupture event in the southwest section of Longmenshan fault zone, which belongs to thrust earthquake. From the perspective of neotectonics and active tectonics, the researchers obtained the distribution characteristics of aftershocks of Lushan earthquake by projecting the accurately located epicentres of main earthquakes and aftershocks on topographic maps and remote sensing images, expounded the characteristic seismic characteristics of Shuangshi-Dachuan fault, and inferred that Lushan earthquake was related to the structural activities of the fault slope at the bottom of Longmenshan structural belt (13 ~ 19 km). At the same time, the development trend of strong earthquakes in the future is analyzed: although this earthquake released the strain energy of the fault, the monitoring results of in-situ stress show that the stress release of the fault zone is not complete, and the possibility of future earthquakes deserves further attention.
Geological disasters induced by Lushan M7.0 earthquake in southwest Sichuan Province, China: typical examples, types and distribution characteristics (basic characteristics of Lushan M7.0 earthquake geological disasters in Sichuan Province). Based on remote sensing interpretation and field investigation results, the development characteristics and hazards of earthquake-induced secondary geological disasters such as collapse, landslide, debris flow and sand liquefaction are briefly discussed. Earthquake geological disasters are mainly controlled by strong earthquake triggering, steep terrain, terrain amplification effect, weak lithology and strong weathering unloading. The research shows that the development and distribution law of geological disasters is mainly reflected in the obvious epicenter effect and landform effect, the footwall effect of active faults is not obvious, and the fault end effect is obvious, which is closely related to lithology and rock mass structure. The geological disasters induced by Lushan earthquake and the destruction of the mountain by the earthquake are hidden and should be paid attention to in post-disaster reconstruction.
6. New progress in the study of major geological disasters in Wujiang River Basin
The project leader of "Study on the Mechanism and Prevention of Geological Disasters in Chongqing" is Associate Professor Li Bin, and the participating units are Chang 'an University, Chongqing Bureau of Geology and Mineral Exploration and Development 107 Geological Team, China Geological Environment Monitoring Station and Chongqing Geological Environment Monitoring Station. This project has completed the application of 3D laser scanning technology and airborne laser radar scanning technology in the investigation and monitoring of geological disasters in the complex landform environment of Wujiang River Basin. By covering DEM, SAR and other data in the study area, combined with the monitoring results of InSAR and GNSS, a set of theoretical methods suitable for large-scale identification of geological disaster deformation in the complex geological environment of Wujiang River Basin is formed. In addition, the project team put forward the deformation mechanism and instability mode of extra-large layered landslide under the influence of karst, mining and other factors, and put forward the stability evaluation method and the analysis model of landslide movement characteristics after the disaster. This set of analysis methods and results can be popularized and applied in southwest karst areas (Figure 50, Figure 5 1).
Fig. 50 Application of InSAR technology in regional geological disaster investigation
Figure 5 1 Cumulative Deformation Map of Jiweishan Landslide (184 days)
7. New achievements of in-situ stress monitoring of key structural parts in the capital circle area.
(1) preliminarily reveals the current tectonic activity and its disaster effect in Qian 'an area at the northern end of Xingtai-Tangshan main earthquake-prone structural belt. It is considered that the geological structure of North China Plain is mainly fault block structure, and the structural system is mostly NNE, mainly compressive and torsional faults, with obvious activities at present. Earthquake activities with M ≥ 5 are usually distributed along NNE, NNE and NWW fault zones, especially at the intersection of fault zones in different directions (Figure 52).
(2) Discussed and analyzed the changing characteristics of the present geostress environment in Tangshan-Luanxian-Changli area and its significance in the study of seismic geology. The results of in-situ stress monitoring in Changli, Hebei Province show that the earthquake of magnitude 9.0 in Japan induced coseismic displacement in North China, and the regional tectonic activity showed nearly east-west extension, and the maximum horizontal principal compressive stress was nearly north-south. However, since June 6, 20 12, North China has been characterized by nearly east-west tectonic compression, and the maximum horizontal principal stress is near east-west, which indicates that the regional tectonic stress has recovered to the direction of the maximum horizontal principal stress in North China before the Japanese earthquake of magnitude 9.0, and earthquakes will occur in the process of changing the direction of the regional tectonic stress (for example, May 28 and 29, 2006.5408.
Fig. 52 Structural Geological Map of Borehole Area for Ground Stress Measurement Monitoring in Chenguanying Village, Qian 'an City
Fig. 53 Monitoring results of in-situ stress real-time monitoring station in Changli County, Hebei Province