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Date submitted2023-07-27
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Date accepted2024-06-03
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Date published2024-12-25
Normalized impulse response testing in underground constructions monitoring
Impulse Response testing is a widespread geophysical technique of monolithic plate-like structures (foundation slabs, tunnel lining, and supports for vertical, inclined and horizontal mine shafts, retaining walls) contact state and grouting quality evaluation. Novel approach to data processing based on normalized response attributes analysis is presented. It is proposed to use the energy of the normalized signal calculated in the time domain and the normalized spectrum area and the average-weighted frequency calculated in the frequency domain as informative parameters of the signal. The proposed technique allows users a rapid and robust evaluation of underground structure’s grouting or contact state quality. The advantage of this approach is the possibility of using geophysical equipment designed for low strain impact testing of piles length and integrity to collect data. Experimental study has been carried out on the application of the technique in examining a tunnel lining physical model with a known position of the loose contact area. As examples of the application of the methodology, the results of the several monolitic structures of operating municipal and transport infrastructure underground structures survey are presented. The applicability of the technique for examining the grouting of the tunnel lining and the control of injection under the foundation slabs is confirmed. For data interpretation the modified three-sigma criteria and the joint analysis of the attribute’s behavior were successfully used. The features of the field work methodology, data collection and analysis are discussed in detail. Approaches to the techniques' development and its application in the framework of underground constructions monitoring are outlined. The issues arising during acoustic examination of reinforced concrete plate-like structures are outlined.
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Date submitted2020-05-19
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Date accepted2021-03-02
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Date published2021-04-26
Results of Comprehensive Geophysical Studies on the Search for Crypts on the Territory of Suburban Necropolis of Tauric Chersonese in the Karantinnaya Balka
The article presents the results of comprehensive studies carried out by the research team of Saint Petersburg Mining University in cooperation with the specialists from the State Museum-Preserve "Tauric Chersonese" in 2019. The purpose of the work was to discover and map antique and medieval crypts (ancient burial structures) on the territory of suburban necropolis of Tauric Chersonese in the Karantinnaya balka. The complex of geophysical methods included continuous ground penetrating radar sounding at two center frequencies of 350 and 500 MHz and contactless electrical tomography. To minimize spatial errors in the process of studies, topographic and geodetic works were carried out. For the first time wave electromagnetic effects were identified, which indicated the positions of hidden underground crypts. Geological factors were established that are favorable for cutting crypts in the layered thickness of Sarmatian limestones. The obtained results allowed to justify the feasibility of continuing geophysical works at the necropolis in order to study interior space of the discovered crypts and to determine the boundaries of archaeological heritage.
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Date submitted2008-10-13
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Date accepted2008-12-15
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Date published2009-12-11
A complex of gravi-, magneto-, electroprospecting аnd geoelectrochemical methods for local prediction and prospecting for hydrocarbon deposits
It is proposed to use interpretational spatial distributions of effective parameters of the medium under investigation instead of measured fields in the process of comprehensive prediction-prospecting investigations. There are used effectively: effective density, effective magnetization, intensity of probable sources of geochemical anomalies.
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Date submitted2008-10-08
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Date accepted2008-12-08
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Date published2009-12-11
Georadar investigations of shallow depth оf geological section and engineering constructions
- Authors:
- V. V. Glazunov
- N. N. Efimova
The GPR-method showing high resolution, great performance and sensitivity to minor variations in the composition and conditions of soils and material has assumed a role of the leading geophysical method for looking at the upper part of the geological section. This paper presents the advanced directions of GPR application for engineering problems solution.
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Date submitted2008-10-15
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Date accepted2008-12-21
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Date published2009-12-11
Prediction of reservoir properties by the acoustic impedance volume
- Authors:
- A. V. Ekimenko
Acoustic impedance and reservoir properties relations are analyzed in this paper. The author researches these relations on three areas in Timano-Pechora oil and gas basin. These relations may be as direct as inverse. Type of these relations depends on wave pattern. If wave pattern is difficult, detailed analyses and modeling are necessary.
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Date submitted2008-10-14
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Date accepted2008-12-21
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Date published2009-12-11
Results of profile magnetotelluric researches at the Ozernoye ore cluster in Buryatiya Republic
Primary results of MT profiles surveys interpretation are presented. The investigations have been carried out in 2007. Ozernoye pyrite-polymetallic deposit is of special interest. Magnetotelluric and audiomagnetotelluric investigations have been carried along one profile, crossing all over the territory of Ozernoye ore cluster, and along some more detailed profiles inside already discovered deposits. As a result of the investigations some new data on relict structure, which is the host of Ozernoye pyrite-polymetallic deposit, are obtaned.
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Date submitted1951-08-03
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Date accepted1951-10-04
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Date published1952-04-24
Field accuracy of geophysical observations
- Authors:
- E. M. Kvyatkovskii
He solution of various geological exploration problems by geophysical exploration methods is generally divided into two main operations: 1) the study of the physical field (magnetic, gravitational, etc.), against the background of normal values of which anomalous values, caused by the influence of various geological objects, are more or less clearly distinguished; 2) geological interpretation of the physical field, i.e. decoding (quantitative or qualitative) of anomalous values As a result of these measurements, sometimes quite complex, including in the overwhelming majority of cases elements of mathematical processing, and in some cases interpretation (seismograms, spectrograms), exploration geophysicists will receive for each point where the measurement was made, a certain value of the parameter of the physical field. Based on these values, graphs, contour maps, vector plans, hodographs, etc. can be constructed, which are the main and only material subject to interpretation in the geological sense of the word. However, before proceeding to the interpretation of the obtained graphs, maps, hodographs, etc., it is necessary to have a very clear idea of their reliability, or, in other words, it is necessary to take into account the magnitude of the error made during measurements, which characterizes the field accuracy of observations. Although the field accuracy of observations is not the only factor determining the accuracy of the geological interpretation of results, in a number of cases it plays a very significant role along with other factors (observation network, physical properties of rocks, etc.).