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This paper focuses on an introduction to seismology and the concept of seismic wave propagation. This article mainly introduces the subjects of seismology, earthquakes, and seismic waves and their types, as well as basic preliminaries related to the subject. The present paper is review in nature and divided into several sections and subsections like the introduction of the subject with a related literature survey, the basic terms of seismology such as earthquakes, seismic waves and their various types, and the last section is the observation of the study along with the list of references used in this paper. This is because these are essential and important phenomena in various fields like geophysics, seismology, mechanics, fluid dynamics, etc., so this paper will be helpful for early researchers to do their research in these fields. Experimental scientists, researchers, and seismologists working in the field of wave propagation in many types of porous medium may find the current theoretical conclusions beneficial. [ABSTRACT FROM AUTHOR]

Geophysical methods are powerful tools to explore site characterization for geotechnics. Among the possible fields of geophysical application are hydrocarbon, mineral and geothermal exploration, disaster mitigation, environmental, slope stability assessments, soil characterization and searching of an archaeological site. The available techniques are characterized by different penetration and resolution capabilities, from a few centimetres to kilometres. This paper presents an original use of Spectral Analysis of Surface Wave (SASW) method to site characterization of soil stiffness, and it will be compared with Standard Penetration Test (SPT), and for rock mass strength identification it will be compared with Rock Quality Designation (RQD). Surface wave dispersion analysis is widely used in geophysics to infer a shear wave velocity model of the subsoil for a wide variety of application (Foti, S. et al., 2011) and to suppose strength of rock mass for RQD parameter estimation. Objectives of the paper are, first to the point that SASW method is an insitu tests, rapid and cost-effective geotechnical investigation, second to show that application of SASW method in the subsoil and rock mass can provide accurate parameters of N-SPT for soil stiffness and RQD for rock mass strength. Finally, some illustrations of the advantages or disadvantages and compare the result of the SASW method with the conventional geotechnical test are presented. [ABSTRACT FROM AUTHOR]

The paper presents a study of the standing wave coefficient of antennas for detecting an anisotropic medium over hydrocarbons. Experimental studies were carried out on real hydrocarbon fields. The results of conducted tests confirmed the increase in accuracy of hydrocarbon deposit boundaries determination on the basis of antennae standing wave ratio measurements by 20 - 30 %. The obtained results can be used in prospecting geophysics for increasing the accuracy of determining boundaries of deposits by measuring antennae standing waves ratio in a wide range of frequencies and for increasing resolving power of deposit positioning by measuring standing waves ratio of two or more antennas. [ABSTRACT FROM AUTHOR]

Different theories of bodily tides assume different forms of dependence of the angular lag δ upon the tidal frequency χ. In the old theory (Gerstenkorn 1955, MacDonald 1964, Kaula 1964) the geometric Iag angle is assumed constant (i.e., δ ∼ χ0), while the new theory (Singer 1968; Mignard 1979, 1980) postulates constancy of the time lag Δt (which is equivalent to saying that δ ∼ χ1). Each particular functional form of δ(χ) unambiguously determines the form of the frequency dependence of the tidal quality factor, Q(χ), and vice versa. Through the past 20 years, several teams of geophysicists have undertaken a large volume of experimental research of attenuation at low frequencies. This research, carried out both for mineral samples in the lab and for vast terrestrial basins, has led to a complete reconsideration of the shape of Q(χ). While in late 70s – early 80s it was universally accepted that at low frequencies the quality factor scales as inverse frequency, by now it is firmly established that Q ∼ χα, where the positive fractional power α varies, for different minerals, from 0.2 through 0.4 (leaning toward 0.2 for partial melts) — see the paper by Efroimsky (2006) and references therein. That paper also addresses some technical difficulties emerging in the conventional theory of land tides, and offers a possible way of their circumvention — a new model that is applicable both for high inclinations and high eccentricities (contrary to the Kaula expansion which converges only for i ≠ π/2 and e < 0.6627434). Here we employ this new model to explore the long-term evolution of Phobos and to provide a more exact estimate for the time it needs to fall on Mars. This work is a pilot paper that anticipates a more comprehensive study in preparation (Efroimsky & Lainey 2007). © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

This paper provides results of a study of the structure of the Batagay (Yakutia) thaw slump by using geophysical methods: the surface impedance (SI) method, the method of vertical electric sounding (VES) on direct current and ground-penetrating radar (GPR) method. [ABSTRACT FROM AUTHOR]

Over the past several decades, there has been a significant amount of research effort in ocean acoustics to develop methods for inverting parameters of geoacoustic models from measurements of the acoustic field in the ocean. This paper reviews the stages in the development of geoacoustic inversion as a statistical inference process to estimate geoacoustic model parameter values and their associated uncertainties. Limitations of model-based inversion methods such as matched field inversion are discussed. The paper concludes by discussing some new approaches that address limitations caused by uncertain ocean waveguide environments. [ABSTRACT FROM AUTHOR]

The paper deals with the results of palinspastic reconstructions of the main structural elements located in the Lesser and Greater Caucasus and their correlation with the adjacent territories. The reconstructions are made on the basis of paleomagnetic data analysis. The regional rotations and displacements have been studied using paleomagnetic measurements of collected data. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present the results of research that continues our previous studies of geoacoustic emission (GAE) responses to weak impacts from varying electromagnetic fields. In this paper, we analyze the probable influence exerted on the GAE response amplitude by the electrokinetic processes associated with the activation of filtration flows during the preparation of a tectonic earthquake of moderate magnitude. The problems of volumetric strain evolution (on the first spatial scale), the change in the fluid filtration rate, and the electrokinetic current evolution (on the second spatial scale) near the measuring well related to the shear modulus heterogeneity are solved successively for the specific seismic event. It has been shown that the change in the electrokinetic current of the G-1 measuring well qualitatively corresponds to the change in the amplitude of GAE measured in this well. [ABSTRACT FROM AUTHOR]

In this paper, the fracture pattern and formation of a sinkhole are estimated depending on the rock properties. The possibility of using geophysical methods for recording and analyzing acoustic emission to monitor and predict the state of the medium is considered. The problem of deformation of the sedimentary cover over the growing karst cavity is solved on the basis of the elastoplastic Drucker-Prager-Nikolaevsky model and the equation of damage accumulation. The specified kinetics of accumulation of damages allows us to describe slow processes of degradation of the strength of the medium under stresses that are low for the development of inelastic deformations. The results are obtained for different values of the strength of karst rock; we show the influence of the kinetic parameters of damage accumulation on the shape of collapse depressions. We also model acoustic emission caused by the material fracture. One can follow different stages of the karst development by looking at patterns of cells which fail at a given time. Our observations show the relation between the intensity of material fracture and the intensity of seismic emission. [ABSTRACT FROM AUTHOR]

The importance of gravity in geodesy is recognized even since the 16th century. Starting with the experiments and theories of Galileo Galilei, the gravity and its global variation has continued to play an important role for those preoccupied with measuring the Earth's surface. The benefits of Physical Geodesy (studying the Earth's gravitational field) are extended to other disciplines such as Seismology, Oceanography, Volcanology etc. The aim of the present paper consists in highlighting the connection between gravity and the geodesist's profession. This was possible only throughout an extended study of Physical Geodesy realized with the support given by the International Gravity Office, Military Topographic Direction, The National Centre of Cartography and different specialists from these domains. Gravity represents the main factor which influences the Earth's shape and dimensions and when it comes to geodetic measurements, the gravity and its influence upon the measurements realized by specialists in geodesy has to be considered. [ABSTRACT FROM AUTHOR]

The evaluation of drainage system's performance is an important thing to do to prevent flooding. Conventionally the Government evaluates the drainage system by opening one by one the lid of drainage and detects the plug manually. This method is not effective and efficient because this method need many people, much time and relatively expensive. The purpose of this paper is to identify plugs in drainage system in G St. at Bandung Institute of Technology by using electromagnetic wave. Ground Penetrating Radar (GPR) is one of geophysics method that using electromagnetic wave with high frequency. GPR is a non-destructive method with high resolution imaging for shallow depth (~100m) and relatively cheap. We could identify the plug without opening the lid manually so that we could save much time. GPR's sensitivity is depends on resistivity, magnetic permeability, and permittivity of an object. The result of this research is we could identify the plug on the radargram that observed by a build-up amplitude anomaly. [ABSTRACT FROM AUTHOR]

Magnetotelluric data acquisition sometimes should be taken on topographic terrain, for example on the mountainous zones. The variety of topography around the point of measurement yields additional effects on the data obtained. Therefore, the modeling of MT responses in the topographic terrain is very necessary to get a complete understanding of topographic effects on MT measurement. This paper will discuss the modeling of topographic effects on 2D MT response function by using the boundary element method. Boundary element method was chosen because of its simplicity in domain discretization, low cost memory and time consuming modeling, and its accuracy to obtain good precision results. [ABSTRACT FROM AUTHOR]

This paper presents the development of the theory of Fresnel Sections, the application and the practical implementation on modern computing architectures. The theory of Fresnel Sections and the term Fresnelabschnitte has been introduced with processing of seismic data. Fresnel Sections are the further stage development from the simple concept of Fresnel Zones which are only valid in non-slanted environments and mostly cannot be used for real underground structures. Fresnel Sections handling slanted structures have been used with wave theory and optical phenomena. Using highly performant computing resources Fresnel Sections and derivates can be calculated for huge data sets as well as for sophisticated application scenarios. [ABSTRACT FROM AUTHOR]

In recent times, research has moved towards using VLF radio transmissions propagating in the earth-ionosphere waveguide as a detector of a variety of transient geophysical phenomena. A correct interpretation of such results depends critically on understanding the propagation characteristics of the path being monitored. The observed effects will vary depending on time of day, path length, path orientation, magnetic latitude and VLF frequency. This paper provides a brief tutorial of the relevant propagation dependencies for medium to long VLF paths best understood in terms of waveguide mode theory together with results either not previously published, not published in the open scientific literature or whose significance has been little recognised. [ABSTRACT FROM AUTHOR]

This paper describes effects of gravity on mobility performance of wheeled rovers for future lunar/planetary exploration missions. A series of model tests of a wheel-terrain system were performed on an aircraft during variable gravity maneuvers, and it became clear that slip of the wheel becomes high when the gravity is less than 1/2G. In addition to the flight experiments, the same model tests were performed in a laboratory on the ground (1G condition). The experiments were demonstrated with variable wheel loads by using counterweights. As a result of the on-ground experiments, the mobility performance under low wheel load conditions was found to be improved contrary to the flight experiments. In case of the flight experiments, not only the wheel load but also bearing in the terrain changes with respect to the gravity level, while only the wheel load changes in case of the on-ground experiments. Thus, running under a reduced gravity condition becomes difficult because the terrain generates higher rolling resistance by sinkage owing to the lack of bearing of the terrain. That is to say, the mobility performance on lunar/planetary surface is likely to be severer compared to the terrestrial gravity condition. [ABSTRACT FROM AUTHOR]

In this this paper the stochastic background of gravitational waves (SBGWs) is analyzed with the auxilium of the WMAP data. We emphasize that, in general, in previous works in the literature about the SBGWs, old COBE data were used. After this, we want to face the problem of how the SBGWs and f(R) gravity can be related, showing, vice versa, that a revealed SBGWs could be a powerly probe for a given theory of gravity. In this way, it will also be shown that the conformal treatment of SBGWs can be used to parametrize in a natural way f(R) theories. [ABSTRACT FROM AUTHOR]

The magnetosheath is a region located between the bow shock and the Earth’s magnetopause. The importance of the Earth’s magnetosheath in space physics is related to its role as a mediator between the solar wind and terrestrial magnetosphere. The magnetosheath should play an important role in the transmission of matter and energy observed in the solar wind through to the magnetopause. Several theoretical models have been developed to understand the plasma and magnetic field properties in the magnetosheath. These models differ in the role that the magnetic forces play in them. The interaction of the magnetosheath with the magnetopause can be described in terms of waves. These waves in general can take various forms, such as oscillation, discontinuities or standing waves and infinitesimal increments. The function of these waves is to reconfigure the solar wind flow and its frozen-in magnetic field from the solar wind state to the state specified by the magnetopause boundary condition. The main characteristics and positions of the wave modes in the Earth’s magnetosheath are briefly summarized. In this paper we estimated the periodicity of the wave modes across the Earth’s magnetosheath using Eigen modes of the global magnetosphere and ideal gas model. In the ideal gas model, we found two values of the periodicity of the Alfven waves corresponding to two different positions in the magnetosheath. The first is, (∼20.4 min) at the magnetopause, while the second is (∼42.36 min) at the bow shock. For the Eigen modes of the global magnetosphere, the periodicity is about (∼16.59 min). From our calculations, we concluded that the Alfven waves could propagate near the inner magnetosheath (at the magnetopause) with shorter periodicity than at the bow shock. These waves should play the required role to explain the observed transfer of matter and energy from the solar wind into the magnetopause. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

So far no general view on the geodynamic evolution of the Black Sea to the Caspian Sea region is elaborated. This is associated with the geological and structural complexities of the region revealed by geophysical, geochemical, petrologic, structural, and other studies. A clash of opinions on geodynamic conditions of the Caucasus region, sometimes mutually exclusive, can be explained by a simplified interpretation of the seismic data. In this paper I analyze available data on earthquake occurrences in Azerbaijan and the adjacent Caspian Sea region. The results of the analysis of macroseismic and instrumental data, seismic regime, and earthquake reoccurrence indicate that a level of seismicity in the region is moderate, and seismic event are concentrated in the shallow part of the lithosphere. Seismicity is mostly intra-plate, and spatial distribution of earthquake epicenters does not correlate with the plate boundaries. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The World Stress Map (WSM) database contains over 16,000 indicators on contemporary crustal tectonic stress and provides an essential parameter for geohazard assessment. This paper focuses on the importance of database accessibility for geohazard assessment and presents the basic concepts and availability of the WSM. The WSM can be applied to several key aspects of geohazard assessment, in particular the mapping of stress patterns and places of stress concentration for improved delineation of zones of seismic hazard. Furthermore, contemporary tectonic stresses can be used in combination with numerical modeling to identify faults or sections of fault systems with high failure potential and can help to predict the likely type of fault reactivation. This approach is especially valuable for assessing the likelihood of strong and rare seismic events for which probabilistic hazard assessment will fail and physically based methodologies are required. Herein, we use the Caspian-Caucasian region as an example to apply WSM data for geohazard assessment. The Caspian-Caucasian area is characterized by the occurrence of a number of stress related geohazards on different spatial scales, in particular crustal earthquakes, seismically triggered landslides and mud volcanism. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Convection in a spherical shell under the influence of a radial force field is an important problem in the geophysical and astrophysical framework. To turn out the earth gravity field which breaks the simulated central force field, such a experiment has to be performed in a microgravity environment. The radial force field is produced by applying a voltage difference between the inner and outer spheres: the dielectrophoretic force. This last field differs from the earth’s gravity one. This paper aims at simulating the bifurcated dynamics in this framework. In particular, motions with a 3D structure are presented. The most of simulation results are corroborated by the bifurcation analysis. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Baneberry, a 10-kiloton nuclear event, was detonated at a depth of 278 m at the Nevada Test Site on December 18, 1970. Shortly after detonation, radioactive gases emanating from the cavity were released into the atmosphere through a shock-induced fissure near surface ground zero. Extensive geophysical investigations, coupled with a series of 1D and 2D computational studies were used to reconstruct the sequence of events that led to the catastrophic failure. However, the geological profile of the Baneberry site is complex and inherently three-dimensional, which meant that some geological features had to be simplified or ignored in the 2D simulations. This left open the possibility that features unaccounted for in the 2D simulations could have had an important influence on the eventual containment failure of the Baneberry event. This paper presents results from a high-fidelity 3D Baneberry simulation based on the most accurate geologic and geophysical data available. The results are compared with available data, and contrasted against the results of the previous 2D computational studies. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

We consider an inverse problem for a one-dimensional fractional evolution equation with involution and with periodic boundary conditions with respect to a space variable. This equation interpolates heat and wave equations. The inverse problem consists in the restoration (simultaneously with the solution) of the unknown right-hand side of the equation, which depends only on the spatial variable. The conditions for redefinition are initial and final states. Existence and uniqueness results for the given problem are obtained via the method of separation of variables. [ABSTRACT FROM AUTHOR]

There have been improvement in the subsurface investigation using non-destructive geophysical method. These were supported by improvement in data inversion method for 2-D resistivity imaging method. This geophysical method have been used for many environmental and engineering studies, such as slope monitoring, cavities detection, buried man-made structures and so on. This paper present the 2-D data inversion in electrical resistivity method which was carried out in Penang, Malaysia. This non-destructive method is used to image the subsurface for soil's lithology purpose. In addition, two inline boreholes were used to validate and verify the obtained results of electrical resistivity imaging. Based on the electrical resistivity imaging, the subsurface is made up of four type of materials. They are sandy silt, silty sand, sand and lastly weathered granite. Sandy silt and silty sand soils give resistivity values of 65-220 Ωm and 120-770 Ωm Meanwhile for sand and weathered granite materials, their resistivity values are 220-1400 Ωm and 410-2600 Ωm respectively. Beside than electrical resistivity imaging, this work also present the distribution of conductivity for the investigated subsurface via the 2-D conductivity model. In conclusion, the used of the nondestructive geophysical method in this study is successful in image the investigated subsurface lithology and the investigation coverage area is enhanced instead of information from two discrete points of the geotechnical boreholes. Therefore, the joint-interpretation of these two technical methods is capable and reliable to give information about the Earth's subsurface lithology. [ABSTRACT FROM AUTHOR]

Bukit Bunuh situated in Lenggong (Perak) is one of Malaysia's most important areas for archeology that revealed many traces of Malaysia's prehistory. Geophysical method especially 2-D electrical resistivity imaging method is non-destructive which is applied in geo-subsurface study for meteorite impact. The study consists of two stages which are regional and detail study with a total of fourteen survey lines. The survey lines were conducted using Pole-dipole array with 5 m minimum electrode spacing. The results of each stage are correlated and combined to produce detail subsurface resistivity distribution of the study area. It shows that the area consists of two main layers which are overburden and granitic bedrock. The first layer is overburden mix with boulders with resistivity value of 10-800 Ωm while the second layer is granitic bedrock with resistivity value of >1500 Ωm. This study also shows few spotted possibility of uplift (rebound) due to the high impact which suspected from meteorite. A lot of fracture were found within the survey area which could be one of the effect of meteorite impact. The result suggest that Bukit Bunuh is under layer by a complex crater with diameter of crater rim is approximately 5-6 km. [ABSTRACT FROM AUTHOR]

The stability of laser radiation line is coupled with different external parameters and their variations. The temperature, humidity, pressure are included in them. At the same time the variations of seismo-acoustical fields in the place of laser equipment location can also be a reason for the laser instability. The presentation of real experimental decisions for the laser stabilization in the natural geophysical conditions is made by this paper. The dramatic results of geophysical observations by means of real laser strainmeters installed on the coast of the Sea of Japan are presented also for different earthquakes. [ABSTRACT FROM AUTHOR]

The formula for the Truncation Error (Et) was constructed from the Taylor series terms of the complex conjugate argument function that were discarded when formulating the derivative equation. The test results using 3 Test Functions show that the truncation of the series in the h2-term, the h4-term and the h6-term has insignificant effect on the computational results of the derivatives. The graphs of the computational results of the Complex Conjugate Approach derivatives with and without including Ets appear to overlap. The Ets for truncation in the h2-term, the h4-term and the h6-term are unchanged or stable for each Test Function. For Test Functions I and II, the Ets are on the order of 10−43 and 10−30, and for Test Function III it is on the order of 10−44. This means that the Ets are extremely small, tend to zero or Et→0 so that it can be ignored. While the Relative Error (Er) of the approach for the 3 Test Functions, both those truncated in the h2-term, the h4-term and the h6-term, are on the order of 10−16 for Test Functions I and II, and on the order of 10−17 for Test Function III. The approach is very accurate because the Ers are highly small or Er→0. For its application in geophysics, the approach was used to estimate the derivative of the total magnetic field anomaly caused by a 2D finite prism-shaped source under the earth's surface, and its result was in the range of -2.3182 x 107 to 1.7945 x 107 nT/km. While in statistics, it was known that the population growth rates of Konawe Regency and North Konawe Regency from 2010 to 2020 were 4,585.7 and 1,696.4 persons/year, respectively. [ABSTRACT FROM AUTHOR]

The large-scale Nuclear Magnetic Resonance measurements in the Earth's magnetic field (Surface NMR method) is a geophysical technique that allows non-invasive investigations of water-saturated rocks. The measuring setup consists of a wire loop on the surface that is energized by one or two pulses of oscillating current. After the pulses are cut off, the free induction decay (FID) and/or the spin echo (SE) signal from groundwater could be measured. SNMR results are averaged over the investigated volume that depends on the loop size and typically varies from 20x20x20 to 100x100x100 cubic meters. The maximum depth of groundwater detection can vary from 45 to 150 m depending on measurement conditions, although an average depth of investigation is generally considered to be about 100 m. Our recent results show that combination of FID and SE allows rendering the SNMR less dependent on the geological conditions. Because of different scales, use of rock samples for calibration of the SNMR-estimate of the water content is difficult or impossible. Thus, for interpretation of experimental data we use a mathematical model that allows computing the theoretical signal generated by groundwater. The processing of SNMR data can provide the depth, thickness and water content of investigated aquifers. For improving accuracy of the SNMR results we use calibration based on borehole pumping test data. Based on the water content and the relaxation time provided by MRS it is possible to estimate the aquifer's hydrodynamic properties. [ABSTRACT FROM AUTHOR]

Energetic Solar particles and Geomagnetic Indices during the last two cycles were given. The data of the grouped flares and 10.7 cm radio flux were obtained from Solar Geophysical data reports by the US Department of Commerce, during the solar cycle 22 and 23. Power spectrum analyses method were used for the data treatments, to find the intermediate-term periodicities, 14, 28, 35 are significant. Long-term periodicities periodicity 154 days appeared, and confirmed with the other results. Halloween storms during Nov. 2003 and its effects on the geomagnetic storms have been studied analytically. The data of amplitude and phase of most common indicators of geomagnetic activities during solar cycle 23 has been analyzed. [ABSTRACT FROM AUTHOR]

There is substantial information showing that the Bee Bluff structure is an impact site and that a residual crater can be identified. The thin hard cap of Carrizo Sandstone, Indio fm calcareous silt and a thin layer of iron-rich siltstone leads to impact processes in which the high pressure release wave proceeds promptly upward leading to a trapping of metamorphic products at the impact interface, a ‘bottom-up’ pressure release. Release of water from goethite binder in the sandstone and from the iron-rich siltstone results in supersaturated steam in mixtures with iron and quartz compounds. Samples with quartz and hydrous iron oxide features are examined with optical microscopy, SEM, EDX and XRD. A quartz grain is found with a well defined PDF set. There is widespread amorphous quartz including lechatleriete. Nanocrystals of α-goethite in the acicular form are common. A condensation sphere from the ‘Uvalde Crater Rosetta Stone’ shows a complex mixture of hematite, goethite, and alpha quartz with a trace of trydimite. Numerous samples are yet to be analyzed. The crater appears to have features that can serve as an Earth analog to Mars craters. A companion paper in the present proceedings summarizes prior work, adds new site detail, reports impact-loading analysis, and describes overall features of impactite samples from the site. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

A nonvanishing value for the Rindler horizon energy is obtained, by an analogy with the “near horizon” Schwarzschild spacetime, contrary to Padmanabhan’s result based on the formalism of Euclideanization of the Einstein action. We show that the Rindler horizon energy is given by the same formula E = α/2 obtained by Padmanabhan for the Schwarzschild horizon, where α is the gravitational radius. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Geophysical Method is one of the methods in the Geothermal field exploration stage to get subsurface image related to Geothermal systems. The MT (Magnetotelluric) survey is one of the important geophysics methods for mapping geothermal system models based on the distribution of resistivity values. The MT (Magnetotelluric) survey can also be used to determine reservoir peaks, delineate reservoir boundaries and determine target areas (sweet zones) properly. In Addition, if existing well data can be available, MT (Magnetotelluric) must also be bound or adjusted to the well data to get the best interpretation results. To confirm the final modeling of interpretation together with other geophysical methods, the Geological method and the Geochemical method are also needed. The wellbore data (from "successful" and "unsuccessful" drilling) contains very valuable subsurface information that can be used to confirm the processing data of MT (Magnetotelluric) resistivity values. Precise and accurate data processing of MT (Magnetotelluric) raw data can ensure the best quality of the final product to reduce the uncertainty of depicting subsurface resistivity. All stages of this activity will eventually be able to redefine the reservoir boundaries and can recommend the target drilling area. And then it can reduce the uncertainty or risk of drilling the next well. [ABSTRACT FROM AUTHOR]

Acoustic emission (AE) is a well-established method for geophysical calculations. Nowadays, it is widely used for damage evaluation. For a better understanding of the damage mechanics of materials such as rocks, the sonic wave that has led to AE, has been used to monitor stresses, which induce crack closure, crack initiation and crack damage. In the present study, an AE system was used to study the behaviour of discontinuities on some Tanjung Enim brown coal samples, which were subjected to uniaxial compression. As such, several samples were vacuumed in a container filled with 100% carbon dioxide (CO2) after the adsorption of high saturated CO2 at a certain pressure for 84 h prior to the testing. Meanwhile, some samples were vacuumed unsaturated. In order to determine whether CO2 had any adverse effect on the strength of coal, the comparison was performed between the unsaturated and saturated samples. Moreover, strain gauges were installed on the samples and the measured axial and volumetric strains were studied in conjunction with the AE counts. By virtue of this, the AE method was reliable to detect the onset of pre-crack initiation and the crack damage stress threshold of the black coal samples. Crack initiation and crack closure of the samples subjected to stress corresponding to the percentage of the peak strength when compared to the unsaturated and saturated samples. Nevertheless, crack damage occurred at a higher percentage of peak strength for in unsaturated condition compared to CO2 saturated samples. The results indicated that sorption of CO2 can cause the reduction in strength of the brown coal samples when tested under the uniaxial compression. As the coal samples were highly heteregeneous, more tests are required to confirm whether the adsorption of CO2 will cause strength reduction in coal. This will eventually identify the actual underlying CO2 sorption mechanisms. [ABSTRACT FROM AUTHOR]

Geophysical methods have been increasingly popular for shallow and environmental studies worldwide. In particular an electrical geophysical method is helpful in soil investigation which focuses on an interval from the ground surface down to a depth of 2 meters. The instrument of electrical geophysics were developed and successfully applied to assist in precision agricultural practices worldwide, i.e. Europe, Russia, and US. Our group from Indonesia has modified a resistivity instrument that integrates with other components and could increase mobility in soil mapping. The instrument measures electrical resistivity, conductivity, and potential that can be used for agricultural applications. In addition, we created forward modelsto help us understand and detect limits of our target. [ABSTRACT FROM AUTHOR]

The study area located at the tropical region which may induced a deeply eroded structure over a complex subsurface. Therefore, the geophysical methods were applied to estimate crater dimension and study the signature of an impact crater. Commonly, an impact crater is characterized with the aid of potential field method which can cover larger area and cost effective. The application of seismic measurements is to complement the potential fields' method for better data interpretation. This study emphasized on utilizing integrated study of geophysical methods which include potential field method (ground magnetic) and seismic for bedrock delineation on impact crater structure characterization. The results induced a positive signs of impact crater which associate with a few indications on crater type and its structures. The integration of ground magnetic and seismic refraction reveal the Bukit Bunuh impact crater is a complex crater. Both of the geophysical methods agreed with the notable size impact crater of 5 km with central uplift at the Bukit Bunuh area. [ABSTRACT FROM AUTHOR]

The present research work elucidates the characteristics of Love waves propagating through a prestressed non-homogeneous orthotropic medium overlying a heterogeneous half-space. It has been considered here that the properties of the layer vary in the direction of thickness with the help of suitable boundary conditions. The dispersion relation has been obtained by variable separable method. A special case has been undertaken in which due to homogeneity of half-space and layer, the dispersion relation satisfies the classical equation of Love waves. To show the nature of Love waves, dispersion curves have been plotted by taking variation in initial stress and inhomogeneities of layer and half-space. This problem may find its applications in various geophysical prospects. [ABSTRACT FROM AUTHOR]

Magnetic data were processed to interpret the geology of Peninsular Malaysia especially in delineating the igneous bodies and structural lineament trends by potential field geophysical method. A total of about 32000 magnetic intensity data were obtained from Earth Magnetic Anomaly Grid (EMAG2) covering an area of East Sumatra to part of South China Sea within 990 E to 1050 E Longitude and 10 N to 70N Latitude. These data were used in several processing stages in generating the total magnetic intensity (TMI), reduce to equator (RTE), total horizontal derivative (THD) and total vertical derivative (TVD). Values of the possible surface and subsurface magnetic sources associated to the geological features of the study area. The magnetic properties are normally corresponding to features like igneous bodies and faults structures. The anomalies obtained were then compared to the geological features of the area. In general, the high magnetic anomalies of the TMI-RTE are closely matched with major igneous intrusion of Peninsular Malaysia such as the Main Range, Eastern Belt and the Mersing-Johor Bahru stretch. More dense lineaments of magnetic structures were observed in the THD and TVD results indicating the presence of more deep and shallow magnetic rich geological features. The positions of Bukit Tinggi, Mersing and Lepar faults are perfectly matched with the magnetic highs while the presence of Lebir and Bok Bak faults are not clearly observed in the magnetic results. The high magnetic values of igneous bodies may have concealed and obscured the magnetic values representing these faults. [ABSTRACT FROM AUTHOR]

The complexity of geology structure in eastern Java causes this region has many potential resources as much as the disasters. Therefore, the East Java province represents an interesting area to be explored, especially regarding its upper crustal structure. To investigate this structure, we employ the Ambient Noise Tomography (ANT) method. We have used seismic waveform data from 25 Meteorological, Climatological and Geophysical Agency (BMKG) stationary seismographic stations and 26 portable seismographs installed for 2 to 8 weeks. Inter-station cross-correlation produces more than 800 Rayleigh wave components, which depict the structure beneath eastern Java. Based on the checkerboard resolution test, we found that the optimal grid size is 0.25ox0.25o. Our inversion results for the periods of 1 to 10 s indicate a good agreement with geological and Bouguer anomaly maps. Rembang high depression, most of the southern mountains zone, the northern part of Rembang zone and the central part of the Madura Island, the area of high gravity anomaly and areas dominated with igneous rocks are associated with high velocity zones. On the other hand, Kendeng zone and most of the basin in the Rembang zone are associated with low velocity zones. [ABSTRACT FROM AUTHOR]

We analyzed the seismicity activity around the Cimandiri fault zone, West Java, Indonesia by using the earthquake catalogs listed by Indonesian Meteorological Climatological and Geophysical (BMKG) and International Seismological Centre (ISC) from 1973 to 2013 (M>=1 and depth ≤ 0-50 km), along with the focal mechanism data from National Research Institute of Earth Science and Disaster Prevention (NIED) from 2007 to 2014 (M>4; depth ≤ 50 km) and Global CMT catalog from 1976 to 2014 (M=0-10 and depth ≤ 50 km). The result from earthquake catalogs suggest that there are earthquake activities around the Cimandiri fault zone in the recent years, which is also supported by the results of focal mechanism data analysis from NIED data and Global CMT catalog. [ABSTRACT FROM AUTHOR]

The geophysical exploration method is the superior over the project area due to the dense of vegetation and thick soil so very limited geological outcrops. Contrast of physical properties of every different rock type should be able to be distinguished by the geophysical data. Fuzzy logic approach and weight of evidence were used for geophysical data modeling. Posterior probability was used to calculate the weight of evidence (WofE) of every fuzzy map memberships. By combining each rock type model, the model provides better result compared from the model from mixed rock type on the data training. This method is able to eliminate the potential interference of different geophysical signature. So that, the understanding the geological feature of the area is key success for the mineral prosperity modeling. We verified the model by site visiting and drilling and it is estimated about 90% confident. [ABSTRACT FROM AUTHOR]

The Diamond Imaging and Coherence beamline I13 consists of two independent branchlines for imaging in real and reciprocal space. Different microscopies are available providing a range of spatial resolution from 5µm to potentially 5nm. The beamline operates in the energy range of 6-35keV covering different scientific areas such as biomedicine, materials science and geophysics. Several original devices have been developed at the beamline, such as the EXCALIBUR photon counting detector and the combined robot arms for coherent X-ray diffraction. [ABSTRACT FROM AUTHOR]

Physical sea surface parameters such as irradiance reflectance are most commonly used in ocean color remote sensing. Algorithms are developed to relate irradiance reflectance (R) and quantities such as chlorophyll and suspended sediment concentration. The study interpreted how many independent parameters of ALOS satellite data collected can be found to assess the sediment concentration in Langkawi Island, Malaysia by using principal component analysis (PCA). PCA is a technique designed for reducing the dimensionality of multivariate set of data. This method can reduce the variables which are highly correlated with one another without losing any information. In order to extract the reflectance quantities, all satellite data sets have been atmospherically corrected using ATCOR-2. PCA and band ratios were applied on the four independent bands (band 1-4). The result from independent band show that the PC1 and PC2 composed mostly of band 2(RAV2) and band 3 (RAV3) reflectances, while the band ratios show that the PC1, PC2 and PC3 composed mostly of all band ratios. In this study, the both components PC1 and PC2 can be considered strong in interpreted the structure of the data of independent band, due to it can explain 98.45 percent of the diversity of data. On the other hand, PC1, PC2 and PC3 can be considered strong in interpreted the structure of the data of band ratios. As a result, multivariate model from band ratios gives adequate relationship between the PC1, PC2 and PC3 against suspended sediment concentrations (SSC) with equation: SSC [mg.L-1] = 89.4 -1.78PC1 - 7.33 PC2 - 90.6PC3 (SE=6.6, R²=0.94.6). [ABSTRACT FROM AUTHOR]

We shall start this panorama of theoretical physics by giving an overview of physics in general, this branch of knowledge that has been taken since the scientific revolution as the archetype of the scientific discipline. We shall then proceed in showing in what way theoretical physics from Newton to Maxwell, Einstein, Feynman and the like, in all modesty, could be considered as the ticking heart of physics. By its special mode of inquiry and its tantalizing successes, it has capturing the very spirit of the scientific method, and indeed it has been taken as a role model by other disciplines all the way from the 'hard' ones to the social sciences. We shall then review how much we know today of the world of matter, both in term of its basic content and in the way it is structured. We will then present the dreams of today's theoretical physics as a way of penetrating into its psyche, discovering in this way its aspirations and longing in much the same way that a child's dreams tell us about his yearning and craving. Yet our understanding of matter has been going in the past decades through a crisis of sort. As a necessary antidote, we shall thus discuss the pitfalls of dreams pushed too far.... [ABSTRACT FROM AUTHOR]