Scientific activity of Department 1.
- Published: Monday, 29 January 2018 12:17
- Written by Ulan Abdybachaev
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- Study of deep structure and geodynamic processes on the basis of modern geological and geophysical research methods and global navigation satellite system
In the region under investigation, in recent years significant advances were achieved in various areas of geosciences:
- Seismo-tomographic models of the upper mantle and crust were created.
- A detailed network of the navigation satellite system was developed.
- A technique for studying the Earth's gravitational field, based on the data of the CHAMP and GRACE satellites was developed.
- Mantle and lower crustal xenoliths are found in the Meso-Cenozoic volcanics of the region.
The synthesis of these data will allow compiling a model of inception and evolution of the intracontinental Tien Shan orogene and its interaction with the Alpine-Himalayan collision belt, which eventually will be reflected in scientific and practical tasks on assessing seismic risk and other geo hazards in the region. Studies are planned to be conducted together with GFZ, Potsdam; Institute of Physics of the Earth, RAS; Institute of Geology and Mineralogy Siberian Branch of RAS; Institute of Seismology of the KR.
- Neotectonics of the Tien Shan and Pamirs, kinematics of the latest and modern faults, paleo-seismology
Neotectonic studies are planned to be conducted in three directions, differing both in the objects of the study and in the methodical methods
- Traditionally, the objects of neotectonic studies are deformations of the pre-orogenic peneplain, as well as the latest and active faults that form the various structural ensembles of the studied area. Methods of structural geology are far from being exhausted.
- Instrumental seismology originates in about 1929, and its network is still not always satisfactory. The solution of the problem of the frequency of destructive earthquakes and the areas of their manifestation is possible due to application of paleo-seismological methods.
- A detailed GPS network is deployed in the region and a rich material on the rates of the earth's surface movement was accumulated. But scientific conclusions directly depend on our ideas about retrospective extrapolation of GPS data deep into geological time. There are three time periods: 20-25 million years; 10 million years and 2-3 million years ago. To find convincing arguments, to what time boundary it is necessary to extrapolate GPS data, we consider as one of the priority tasks of the department.
The solution of applied seismology problems (seismic risk assessment, forecast) had always been and still remains relevant for the Pamir-Tien-Shan region. The necessary initial step in assessing seismic risk consists of two tasks:
- determination of places of possible occurrence of strong earthquakes foci;
- construction of a seismic energy attenuation model.
Geological and seismic statistics were traditionally used to solve the first problem. The state of the studies of the modern geodynamics of the Tien Shan orogene by geophysical methods suggests that the use of data on focal mechanisms for assessing the seismic activity of deep and surface structures can be very promising. In this direction, the following tasks are supposed to be solved:
- Interpreting the speed structure of the Tien Shan lithosphere (in cooperation with T.M. Sabitova (Institute of Seismology NAS of the KR) and L.P. Vinnik (IPE RAS)
- Studying the mechanisms of earthquake foci as a basis of dynamic models for the Tien Shan orogene
At the present time there is a lack of data (records of strong movements) for the Central Asian region to solve the second task. However, such a task needs to be set and agreed with N.N.Mikhailova (National Nuclear Center of Kazakhstan) on the supervision of such studies, which should consist of the following stages:
- Creation of a database for strong movement records;
- Development of a network of observations for strong movements records;
- Interpretation and construction of an attenuation model.
Complex research of geoh azards is planned to be carried out in two scientific directions:
4.1. Engineering geology for disasters’ prevention
Geo-catastrophes are characterized by casualties, huge economic and environmental loss. Studies of disasters in Central Asia are planned to be carried out with the relevant agencies applying an interdisciplinary approach using space images, aerial photographs, GPS and MHR 01 C measurements, seismic, hydrogeological, engineering geological, geo-cryological, neotectonic and geodynamic electronic mapping. The results will be submitted to the Ministry of Emergency Situations and relevant agencies as well as training materials for students and schoolchildren in the field of geohazards.
4.2. Engineering Geonomy (IGN). Risk Assessment from Emergencies
IGN research will be conducted in the Central Asian region on a complex of multi-stage dangerous processes and phenomena of seismic hazards, landslides, cosmoplanetary threats and global climate changes based on the methodology of integrated assessment of geo-risks, early warning and forecasting of disasters. The results will be submitted as an assessment of the risks of possible disasters to the MES and profiling organizations, as well as for the education of schoolchildren, students and the public.