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The main aim of this thesis is a concise overview of geoelectrical resistivity methods and modelling in these methods. In the first part of the thesis the theoretical basis of resistivity methods is presented together with a brief description of particular examples of realization of field survey, namely the resistivity profiling, vertical electrical sounding and multielectrode resistivity method. The second part of the thesis is dedicated to description of forward and inverse problems in resistivity methods. The last chapter is focused on the resistor network model and contains several examples of practical calculations of this model. Key words - electrical resistivity method, resistor network, Kirchhoff's law

6 Abstract (ENG) The thesis deals with the use of geophysical methods for non-invasive monitoring of geological processes occurring in crystalline massifs. Such a methodology can be used, for example, in monitoring the processes in future and existing deep geological repositories. The main geophysical methods monitoring changes in the rock mass are multielectrode electrical resistivity tomography (ERT) and high-frequency seismics. Monitored parameters that change over time are the apparent electrical resistivity and parameters of excited elastic waves. Based on long-term measurements at the field bases, changes in the rock mass are described. Interpretations of such changes are made using our own laboratory measurements quantifying the effect of groundwater saturation of samples and the effect of sample disruption (mechanical / thermal) on their electrical resistivity. With respect to modelling and interpretation of the apparent resistivity cross-sections the sensitivity function calculation was proposed and carried out in the geometry of used field layout. It was proven that seismic transmission may be carried out in an underground work reliably for long time. Seismic measurement shows that in the environment of underground works excavated decades ago, we practically do not observe any changes in the...

(EN) Thesis deals with an approximation of static moduli in wells from dynamic moduli determined by acoustic well logging using T-matrix model. Proposed approach makes possible to determine moduli values, which are close to values of static moduli, which would be determined by loading tests. This approach is based on an idea, that an intact rock with sufficiently high compressional strength sc and sufficiently high value of static Young's modulus Es, manifests more or less linear elastic behaviour. In such case, the values of static and dynamic moduli are identical. This fact has been experimentally verified for rocks with values of sc and Es in order of higher tens of MPa and GPa respectively. In case of a rock damage presence in such rock, it's behaviour becomes nonlinearly elastic. The amount of nonlinearity is proportional to increasing amount of rock damage. This results in the difference between values of static and dynamic moduli. T-matrix model is used to quantify this difference. This model is based on an anisotropic rock matrix with ellipsoidal inclusions. These inclusions can affect each other. The result of this model calculation is a group of values of elastic constants, which we call effective moduli. These effective moduli include the effect of porosity in the rock as well and they...

The appearance of seismic activity after construction and filling of a water reservoir has been observed in many places around the world, including localities considered to be formerly aseismic. Occurrence and intensity of these earthquakes are determined by water reservo- irs' parameters, filling and discharging states and by local geological conditions and regional tectonic stress. The thesis firstly deals with two of the world's known significant hydroseis- micity examples and described is also seismicity in Nový Kostel area. The different types of hydroseismicity are thoroughly described along with all the major differences from ordinary earthquakes. The thesis further explains how water reservoirs may affect conditions important for earthquake occurrence such as hydrostatic pressure increase, pore pressure increase, and groundwater flow. These influences are related to water level fluctuations and therefore are described methods to analyze the relationship between earthquake occurrence and water level changes. Classical methods of crosscorrelation and frequency analysis are explained as well as not so common method of SSA (Singular Spectral Analysis). In the last section are all of these methods listed above applied to seismic data from the Nový Kostel area and water level measurements from...

Aim of this thesis was to compare four different methods of construction of velocity sections in seismic prospection: t0 method, general inversion method, method based on presumption of linear velocity gradient medium and tomography. Each method assumes medium with different characteristics, calculations solve both direct and inverse problems, various types of seismic waves are utilised in calculations. It was determined, under which conditions any of afore mentioned methods can be used in common 2D seismic survey. Further on the thesis examines alternative source of seismic energy - set for dynamic penetration testing, which is commonly used in engineering geology. This source is compared to standard seismic hammer source. The thesis evaluated possibility of use this alternative source in seismic survey.

This thesis briefly summarizes the use of seismic survey methods conducted offshore for the purpose of oil and natural gas exploration. Specifically it deals with seismic reflection method which is mostly used in marine exploration. The aim of this work is briefly introduce the fundamentals of the seismic exploration method, principles of used equipment and the measurement process itself. More over the thesis also shortly presents the composition of hydrocarbons and the process of their formation and accumulation in the geological environment. Last but not least it deals with the data processing and interpretation of seismic data.

The objective of this thesis is brief overview of shallow seismic survey and its applications. Particularly they are refraction, reflection, borehole seismology, surface wave methods and applications of their principles in solving problems in near surface. First part of the thesis deals with basics of seismic survey methods. Next part is focused on specification of shallow survey and its application on specific tasks. The results of this thesis is review of methods and tasks that we can already solve and confirmation of untapped potential of shallow seismic methods. Keywords: shallow seismic, refraction, reflection, seismic survey

The purpose of the bachelor thesis is to compile an overview of the information about sources of seismic energy used in land seismic survey. At the beginning of the thesis, the physical basis of seismic methods is mentioned. Basic types of seismic waves are briefly described and the specific of the spread of seismic waves through the rock environment is mentioned. It is followed by a chapter about the history of land seismic sources, which maps their use approximately since the half of the 19th century till the beginning of the commencement of a method Vibroseis in 1950's and 1960's. The overview of seismic sources is in the chapter called Land seismic sources division. Seismic sources are divided into those, which use chemical explosives and mechanical sources. Mechanical sources are divided into impulsive, vibratory and special sources. The attention is paid to their technical parameters and other properties (for example chemical composition in a case of explosives), which is supplemented by examples of commercial sources. There is also present an experimental part in the thesis. There is tested a faculty electrodynamic vibrator. It enables to generate vibratory signals of any time course. The frequency characteristics of the vibrator was experimentally determined. A faculty seismograph Geode and...

The objective of this thesis is seismic survey, namely brief summary of a few selected new methods and technological modifications used in seismic survey of hydrocarbon deposits. The work focuses on a cable-free land seismic system, using optical fibre as acoustic sensors, technical improvements of vibrating units in Vibroseis technology and ocean bottom seismic while using VectorSeis Ocean technology. In the beginning concise historical outline and technical overview of progress from earthquake seismology to seismic survey is performed. Keywords: Seismology, seismic survey, hydrocarbons

Submitted PHD thesis is focused on fracturing process of migmatite, which is a low porosity anisotropic rock. Migmatite, from a locality Skalka, was chosen as a suitable experimental material, namely due to its macroscopically visible, plane-parallel structure (foliation). The fracturing was studied by means of uniaxial loading experiments on cylindrical samples with different dip of migmatite foliation: 13ř (subhorizontal), 81ř (subvertical) and oblique (47ř and 67ř). The net of eight piezoceramic transducers was employed for ultrasonic sounding (US) measurement and acoustic emission (AE) monitoring during the loading experiments. Realized study of migmatite fracturing is based on the interpretation of both mentioned ultrasonic methods. Part of this work was a software development, including its testing for processing and interpretation of measured AE and US data. Methodical part of the thesis consists of: development and testing of algorithms for automatic P wave arrival detection; introduction of anisotropic velocity model to describe magnitude and orientation of velocity anisotropy, as well as to localize AE events in anisotropic velocity field; determination of crack initiation stress using first arrival amplitude of US. Based on the interpretation of AE and US data, there was found a...

The purpose of this diploma thesis is to apply complex seismic attributes on 3D seismic data from Mistelbach block area and trying to figure out whether they are useful by seismic interpretation process. The geology of Vienna basin and the characteristics of Complex seismic attributes will be discussed. The thesis also includes analysis of the Lednice 11 gas reservoir and a new potential hydrocarbon reservoir identification, both using complex seismic attributes.

Summary: The earthquake, one of the natural disasters, affects the lives of people and their properties even in today's advanced age. Seismology and Geology have made a significant progress in understanding the physical and geological phenomenons connected to earthquakes. Thus many consequences of earthquakes can be considerably reduced. Seismic risk estimation and a proper use of antiseismic elements in structures of resistant buildings as well as of early warning systems significantly lowers the impacts of this destructive element. Especially the correct and on-time prediction could contribute to an effective protection from earthquakes but this still remains a challenge for geologists worldwide.

Submitted Ph.D. thesis is concerning the application and interpretation of seismic surface waves in a broad range of frequencies and scales. Using surface waves as a supplement to the methods dealing with body waves seems to be worth the effort. Surface wave interpretation can be used to obtain new information about the studied medium and simultaneously it can overcome, in some cases, the limitations of other seismic techniques. Moreover, surface waves are usually present on measured records and hence for its usage it is not necessary to modify the standard measuring procedures. One of the results of this thesis is an original algorithm for dispersive waveform calculation. The program works in an arbitrary range of frequencies and scales. The input parameter for the calculation is the dispersion curve. In this point the algorithm differs from all other approaches used so far. Algorithm is based on a summation of frequency components with shifts corresponding to the velocity dispersion and distance. The resulting waveform only contains an individual dispersive wave of the selected mode, thus being particularly suitable for testing of methodologies for dispersive wave analysis. The algorithm was implemented into the program DISECA. Furthermore, a new procedure was designed to calculate the dispersion...

The goal of this bachelor thesis is to offer an overview on technics of seismic tomography, their history and general usage. It's focused mainly on description of pioneering efforts in building mathematical tools of tomography and their application in geophysics. Methods mainly discussed are: Herglotz - Wiechert inversion, first numerical studies like ACH teleseismic method, Aki & Lee method of local sources inversion and early global mantle velocity studies. There are also discused some shortcomings of tomagraphy models and their influences on interpretation of results.

This work is focused on the groundwater flow and transport of contaminants in the environment of granitic rocks. Mainly adjective and dispersive types of transport of contaminants are discussed in this work. Transport of contaminants by diffusion is mentioned only marginally in relation to porosity of rock matrix. The main aim of this work was to characterize hydraulic and mechanical-physical parameters of the granite. Partial objectives were to verify the sealing function of the laboratory grout mixture in fractured granite blocks, to characterize the porosity and hydraulic conductivity of the granite matrix at laboratory scale, to find connection between boreholes in situ and to establish a link between the structure of rocks and velocities of seismic waves. Four bentonite and cement mixtures in different weight ratios have been selected as a grout mixture. Suitable injection mixture was selected based on the results of hydraulic conductivity coefficient, and other aspects, such as volumetric stability. The granite blocks were partially grouted by using of the selected grout mixture. Hydraulic conductivity and porosity of the granite rock matrix from the Panské Dubenky test site was tested at three laboratory samples. Hydraulic conductivity was determined with different constant hydraulic...

The work shows today's possibilities of protection against earthquakes and their consequences. Attention is paid to the possible structural modifications and early warning system. Discussed are also the possibilities of earthquake prediction and methods of evaluating seismic hazard and risk.

The processing and the interpretation of the geophysical data measured by the author of this thesis in the Bedřichov gallery (municipal of Liberec) is the main goal of this diploma paper. Earlier data measured in the gallery by G IMPULS Praha spol. s r.o. staff members in the period between 2003 and 2010 are further used to support the assessment. The tunnel which serves to convey water from the Josefův Důl storage reservoir to the water treatment plant in Bedřichov is driven in the granites. These rocks are considered as a highly appropriate host medium for the future deep repository of radioactive wastes in the Czech Republic hence the gallery could be an appropriate place for testing of geological, geotechnical and geophysical methods for purposes of deep repository. The tunnel was driven using two different methods, which allows assessing of the impact of the driving type on the rock disturbance. The tunnel is open for a similar period, which is being considered between the start of operation and the closure of the deep repository hence it's possible to consider time-changes in the goaf. First chapters of this thesis present a brief insight into the problems of the development of the nuclear waste deep repository. The results of the measurements, which are interpreted in this diploma paper, were carried...

SUMMARY: This work deals with the San Andreas fault as a tectonically active area. It includes basic information about the fracture, its origins and history. The work shows, as scientists are now trying to combat the risk of impending earthquakes. Project of San Andreas Fault Observatory at Depth and individual predictions of the next earthquake rupture are described.

In this diploma thesis is at first a revision of field used process of interpretation of full acoustic well logging record in WellCAD program. This program uses an algorithm based on velocity analysis which uses semblance principle. Furthermore an independent interpretation of same data has been done in MATLAB program. In this one, individual steps of the process are verified using analysis of complex seismic trace - in particular by using instantaneous frequency. Both processes of interpretation were applied on wide spectrum of Bohemian Massif rocks with very different mechanic properties, so their robustness has been tested. The results of both interpretation processes have been compared and there haven't been found any fundamental differences, just minor, which can't be systematically eliminated with regard to WellCAD's capabilities. Interpreted values of Poisson's ratio and velocities of longitudinal and transversal have been used for comparison. As the credibility of mechanic parameters' values determined by interpretation processes mentioned above has been proven, other reasons of difference between mechanic parameters' values determined seismically and using static methods were searched for. At first a comparison of basic aspects in which the measuring methods differ (e.g. sample size,...

When producing oil from a thin layer with a gas cap, gas is generally unwanted since the reservoir looses pressure. The pressure loss might cause the fluid vertical migration and therefore a misplacement of the horizontal production well. This is the main reason why the oil production is held back when a gas breakthrough occurs. The well is chocked, or run on lower production rates, until the oil column is recovered, but it is not known how long this will take. If the gas-oil contact could be monitored over time, then the gas breakthrough could be better prevented by reducing production from a particular well branch or even by blinding a specific part of the branch. The aim of this research is to test if monitoring of the gas-oil contact by a seismic acquisition inside the horizontal well is feasible. This could be done much cheaper, more often and with better repeatability than classical 4D seismic. The feasibility was investigated on 2D Troll subsurface models, using finitedifference acoustic modelling. Receivers are planned in the horizontal part of the production well and suggesting the best source position was one of objectives. The influence of variations in geological settings was also investigated. The most accurate information about the gas-oil contact shape and its distance from the well is...