GEOECOLOGICAL RISKS OF TECHNOGENIC NOISES AT LOW FREQUENCIES

The article considers the estimation and prevention problem of ecologically dangerous influence of technogenic noises generated by moving transport, such as heavy tracked and wheeled transport, railway transport. The influence on the man and the environment of a low-frequency controlled CV-40 seismic vibrator [1] used for seismological research separately is considered. The influence of vibrations located in the area of low and infra-low frequencies is estimated. The field records of technogenic noises are analyzed. Numerical analysis and estimation of levels of geoecological risks associated with seismic vibration in the ground and acoustic oscillations in the atmosphere are presented. Spectral and spectral-time analysis of technogenic noises records are performed. The main ecologically dangerous frequency areas, which are the most characteristic for these sources, are separated. The dynamics of changes of the vibration velocity level over distances for heavy wheeled and tracked types of transport has been determined.

INTEGRATION OF KNOWLEDGE AND DATA IN THE TASKS OF ENVIRONMENTAL MONITORING OF EXPLOSIONS

This article is devoted to the problem of integrating knowledge and data in the field of geo-ecology. The study of the dependence of the impact of technogenic explosions on various objects on a complex of natural factors is an important component of forecasting geo-ecological risks. The methodology of geo-ecological risks assessment has been developed in ICM&MG SB RAS, in which a low-frequency seismic vibrator is used as an instrument. Vibration sources provide stable emission of seismoacoustic signals with specified parameters, which allows them to be used as test signals. The paper considers the aspects of the development of the scientific information system "Active seismology", into which the experimental data of geo-ecological monitoring of explosions were integrated, and the Knowledge Portal, which provides navigation and meaningful access to information resources of the subject area.

SEISMIC IMAGING USING AN E-VIB - A CASE STUDY ANALYZING THE SIGNAL PROPERTIES OF A SEISMIC VIBRATOR DRIVEN BY ELECTRIC LINEAR SYNCHRONOUS MOTORS (LSM’S)

Seismic imaging characteristics of a prototype electrically driven, linear synchronous motor (LSM) based, vertical-force seismic vibrator (“e-vib”) were evaluated at a site in the Netherlands. The system weighs 1.65 t and excites seismic signals with a peak force of 6.7 kN. Data were recorded along two collocated geophone based-nodal and landstreamer MEMS-based (micro-electromechanical sensors) 2D seismic profiles. To obtain a broad bandwidth dataset, the e-vib operated with a 1-200 Hz linear sweep. Shot gathers of the merged nodal-landstreamer dataset show good quality seismic data of a broadband nature. The processed merged dataset demonstrates high-resolution reflections of the stratigraphic members from approximately 200 m to 2 km, with visible reflections as deep as 2.5 to 2.9 km. As a reference, we also processed a legacy 3D microspread dataset acquired at the same site with a magnitude stronger (14.1 t, 67.5 kN) hydraulic vibrator. Comparison of our nodal-landstreamer seismic section versus 2D slices extracted from the processed microspread volume suggests similar signal penetration depth and same key marker horizons seen in both. Analysis of the reaction mass and base-plate accelerometer signals recorded with the e-vib source operating both on grass and asphalt surfaces shows that the e-vib has low total harmonic distortion. The results obtained indicate that, although relatively small, the e-vib is capable of generating high-quality, broadband seismic data.