Dynamics of postseismic tectonic deformations

: pp. 228 - 230
Received: August 01, 2013
Carpathian Branch of Subbotin Institute of Geophysics of NAS of Ukraine
Carpathian branch of Subbotin Institute of geophysics of NAS of Ukraine

Aim. The purpose of researches – continuous monitoring observations of geophysical fields, determined by the need of fundamental and applied geophysics and geology for reliable and detailed regional data on the behavior in time and space components of geophysical fields generic modern dynamics of the earth's crust, especially in seismically active regions. Such data are also needed to evaluate the durability and reliability of critical and dangerous geological and geotechnical hazards. Their preparation for today is only possible when observing seismic, gravimetric, tiltmetric, as the strain techniques, which are the main (basic) techniques for monitoring observations of the dynamic regime of the crust. Other research methods are complementary, it is - elektroresistivity, elektroteluric, magnetic, radiogenic and digital techniques - (geological and surveying - GPS, GLONASS). Methodology. The methodology includes a methods of study of strain-stress state of crustal rocks and are determined by the strain tensor and the stress related by Hooke's law, that is, knowing the elastic constants of rocks and the behavior of the components of the strain tensor, we can determine stress in rock mass and to estimate the loading of the medium. Uniform linear array is 3 and 3 sliding independent components, which are used for the registration of strain (linear) and inclinometers (sliding) components. But the crust is heterogeneous. This fact determines the need for appropriate tiltmetric - deformation observations and research on a specially created network of geodynamic stations in real time. Results. The results of the analysis of the series of deformation observations during 2007-2012 allowed to study the time evolution of the process of destruction and subsequent collapse of the rocks forming the ceiling of the gallery, as well as to compare the spectra of seismic events made deformometer geophone and SM-3 during seismic activity. The results of processing the series of observations studied seasonal strain which are relatively large and apparently mostly of meteorological origin. On the construction of a series of observations often appear impulsive disturbance that shows the processes of cracking in the rock mass. To search for possible earthquake precursors, the behavior of the deformation curve before, during and after local earthquakes and the comparative analysis of the series of deformation and seismic observations. It revealed some abnormal phenomena, not recorded by seismometers: bay-like and table-like abnormal deformations [Kravets, Malytskyy, 2010]. It is suggested that table-like anomalies can be considered as a possible effect - a harbinger of the local seismic events. In addition to investigating the dynamics of deformation post-seismic Transcarpathian seismically active zones (Fig. 1), the instrument makes it possible to investigate the surface waves and the Earth's natural oscillations in the frequency range from ultra-low (0 Hz), which produces a strong (4-9 points), the world's earthquakes (Japan, Indonesia, Chile, China, South Australia, etc.). Seismic activity in these regions is very high. Allocation of seismic energy occurs in the context of all layers of the mantle up to a depth of about 700 km. Spectral analysis of generated at the epicenter of the earthquake post-seismic distant waves allows to differentiate their depth and characteristics of the mechanisms to develop and apply mathematical techniques to determine the seismic-dislocational component (offset rupture) to detect deformations and other laws, and to apply these results to the study of modern Transcarpathian tectonic activity. Scientific novelty. Analyzes and detailed features of modern geodynamics due to seismicity in the Carpathian region of Ukraine. The measured length of the recorded deformograph in Transcarpathia individual post-seismic surface waves reached 400 km. This indicates that seismically active regions may interact and influence each other, and may include very slow earthquake thousands of kilometers away in other seismically active areas. Practical significance. The results of deformation measurements carried out in the Transcarpathian seismic zone are analyzed, processed as studying the modern tectonic process caused by lithospheric and post-seismic activity. The research results provide an opportunity to more reliably assess the level and characteristics of the seismic hazard of the Carpathian region of Ukraine and specific activity seismic zones.

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