Engineering Geophysics

Abstract: Two dimensional Electrical Resistivity Tomography (ERT) method was used to investigate a Dam site in Shaqlawa-Erbil
Governorate, NE Iraq, to delineate the nature of the subsurface structures to assess its suitability for the construction of dam. The main
objectives are to investigate the depth to the bedrock, possible geologic structures, such as possible presence of faults, fractures, voids
and clay in the dam axis and abutments. The selected method has the possibility to give an image of the subsurface and map lateral and
vertical variations in the subsurface geology of the site. For this purpose, the (SYSCAL Switch and SYSCAL Pro Switch units)
equipment was used with Wenner array (48 electrodes). Three 2D electrical resistivity tomography profiles were conducted, the space
between electrodes is 5m and the length of the profiles are 235 m. The depth of the investigation is assumed to be 40 m. The acquired
data were inverted to tomogram sections using tomographic inversion by using TomoLAB commercial software. The Tomography
sections show that the subsurface is classified into three distinct geo-electric layers, with different resistivity values; starting with high to
moderate resistivity value represents unconsolidated coarse materials such as boulder and gravel, while in some location fine soft
materials such as silty clay has been appeared that is underlain by a second layer of high resistivity has been detected within upper Fars
(Injana) Formation; it is mainly composed of sandstone saturated and/or compacted. The third layer has low resistivity which represents
the fine materials deposition of the Upper Fars Formation. These results are confirmed and verified by using several boreholes data
were drilled on the recommendation of the surveys. The results showed that the site is suitable for the construction of the proposed dam.

Geophysical Investigation was carried out along Ugbogbo road, Secretariat area in Igarra, Edo State Nigeria. In this area, the self potential method, electrical resistivity method of both the horizontal profiling technique and the vertical electrical sounding were adopted to determine possible causes of road failures which are basically geological, and recommend solutions to this problem.
A total number of 10 Vertical Electrical Soundings were carried out. The geo-electric interpretation and the inverted 2-D resistivity structures of the wenner-schlumberger technique revealed three subsurface layers: the topsoil, weathered layer and the presumed fresh bedrock. The topsoil resistivity ranges from 32 to 936 ohm-m and with an average thickness of 2.2 m. The topsoil is underlained by the fractured layer of apparent resistivity of 11.3 to 67 ohm-m and average thickness of 20 m. Along the transverse, some part of  the topsoil (10 m,115 m)  especially at the area where the stream was flowing underneath across the road (at 190 m) are suspected to be either clayey sand or water saturated. This study reveals that transverse is not really fit for road construction and some excavation and filling should be done before road construction.

Seismic wave velocity, geological and geotechnical properties of the shallow ground layers at Wadi Al-Aslaa area were used integratiuely to study the permeability coefficient (K) and to evaluate the foundation layers occurred beneath the dam and lake construction at this area. The area is located at the northeastern part of Jeddah city, Kingdom of Saudi Arabia and undergoes construction phase. The stratigraphy of the site consists mainly of Precambrian Basement rocks in most parts of the area and by Miocene succession of conglomerates and sandstones at the northeastern parts of the area. The permeability coefficient (K) was estimated across the different sections of the study area. The obtained results of the permeability coefficient help in establishing the suitable precautions, which may taken into consideration during the dam and lake construction phases.

Telah dilakukan penelitian struktur patahan di Sungai Cinambo, Jatigede, Jawa Barat (9/05/15). Penelitian ini bertujuan untuk mengidentifikasi struktur geologi serta nilai strike dan dip batuan di sepanjang Sungai Cinambo. Dari pengukuran menggunakan kompas geologi didapatkan nilai strike dengan tiga kali pengukuran sebesar N 1050 E, N 1070 E dan N 1100 E, dengan dip 370, 360 dan 300 pada stasiun 1 dan 2. Data dikorelasikan dengan sifat-sifat geologi batuan. Hasil interpretasi data menunjukkan adanya struktur patahan yang sebagian berupa sesar naik yang terbentuk akibat proses perlipatan yang juga menyebabkan suatu tekanan dan membentuk struktur antiklinorium di stasiun 8. Kemudian dilakukan pengukuran strike pada sayap selatan sebesar N 1200 E/300, dan sayap utara N 800 E/600. Pengolahan data dilakukan dengan menggambarkan hasil pengukuran ke dalam wulf's net. Hasil interpretasi menunjukkan adanya Plunge, yaitu perpotongan antara sayap utara dan sayap selatan antiklin.

Kata Kunci: Cinambo, Patahan, Antiklin, Strike dan Dip, Plunge.

Лаборатория по Археогеофизика
http://www.phys.uni-sofia.bg/bul/departments/ucsrt/agpl/index.html
Лабораторията е създадена през 2006 г. за внедряване на космически технологии (георадари) в търсенето и геофизическите проучвания на археологически терени у нас.
Лаборатория по Палеолуминесценция (Paleoluminescence lab.)
Лабораторията използва методи и апаратура разработени във Физическия факултет. Те са обект на 3 български изобретения и един канадски патент на екипа на лабораторията. Някой от устройствата разработени и използвани от лабораторията нямат аналози в чужбина, други са обект на многобройни опити за копиране или видоизменения от други лаборатории по света.

Near-surface cavities in karstic carbonate regions are of a particular engineering concern due to their propensity to cause ground subsidence and hazardous effects on the constructions. In a case study at Al-Hassa area, Kingdom of Saudi Arabia (KSA), traditional application of probing techniques has not thoroughly covered the study area due to economic, technical and time limitations. Therefore, buried near-surface cavities became a threat to the proposed constructions in the vicinity of the study area. In this paper, the application of an integrated geophysical survey to delineate the concealed cavities using ground penetrating radar (GPR) and 2D electrical resistivity tomography (ERT) will be presented. Cavities located down to 4 m below natural ground level were well detected by GPR, while those situated deeper than 4 m were well detected by 2D ERT. Correlation between geophysical and engineering geological data has shown a good agreement, indicating the great benefit of geophysical investigation in identifying the ground conditions for major engineering projects in karstic regions like Al-Hassa area. Around thirty two detected cavernous zones were confirmed by borings, and were subjected to suitable ground remediation.

Integrated geophysical investigation, involving the electrical resistivity and magnetic methods was carried out along the Igbara-Oke – Igbara-Odo roadway in Ondo/Ekiti State. This was with a view to investigating the cause(s) of the persistent pavement failure recorded over the years along the road, in spite of repeated rehabilitation works. The resistivity survey utilized 1-D Vertical Electrical Sounding (VES) with the Schlumberger array and 2-D imaging with the dipole-dipole array while profiling technique was adopted for the magnetic survey. Two (2) stable and two (2) unstable segments were identified for the geophysical investigation. Total field magnetic data were acquired along the identified segments of the road at 5 m intervals. The data were corrected for diurnal variation and offset and presented as residual magnetic profiles. Both qualitative visual inspection and quantitative (2-D modeling) interpretations were applied to the resulting residual magnetic profiles. The 2-D dipole-dipole profiling data were acquired along the magnetic traverses. The 2-D data were inverted into 2-D resistivity structures and were used to constrain the location of the nineteen (19) VES stations. The VES curves were interpreted quantitatively and the results were used to generate geoelectric sections. The magnetic profiles, 2-D magnetic models, 2-D dipole-dipole images and the geoelectic sections along the stable segments were characterized generally by relatively high resistivity (> 151 Ωm) weathered layer; significantly thick (>1.5 m) lateritic subbase; A and KH type curves with increasing layer resistivity and hence competence with depth, within the upper two layers and a subsurface devoid of geological structures (faults, fracture or joints). Along the failed segments, relatively thin (< 1.5 m) or non existing lateritic subgrade; low resistivity weathered layer(< 151 ohm-m);H type curve starting with decreasing resistivity typical of incompetent substratum and subsurface geological structures suspected to be faults, fractures, joints or lithologic boundaries characterized these segments. This study concluded that failures along the investigated roadway were caused by clayey subsoils with relatively low resistivity (< 151 ohm-m); differential settlement on road segment cut into saprolite (decomposed rock rich in clay) and presence of geological structures such as lithologic boundaries, faults and fractured zones.

Al-Zayyan Temple or Qasr Al-Zayyan might be regarded as one in a chain of several fortresses that the Romans built to secure the salver's trade caravan route between Asyut and Sudan, known as Darb Al-Arbain. Al-Zayyan temple lies about 25 km south of Al-Kharga city, the capital of the New Valley, and deviates to the east of Al-Kharga-Paris main road some 2 km along the Al-Zayyan-Aarif minor road. The background information about the temple is very scarce, and even what is known is neither clear nor accurate. Some indications have ascribed it to Amenebis and that it was restored during the reign of Emperor Antoninus (AD 138–161). An integrated ground-penetrating radar (GPR) survey using the SIR 2000 Geophysical Survey Systems, Inc. (GSSI) together with magnetic survey using FM36 (GeoScan) and the three component fluxgate gradiometer TRM-70D (Tokin) have been applied to the western side of the temple. The results show relatively large-scale buried structures in a direction intersecting that of the present temple at about 45 °. Some particular features within the structure have been speculatively ascribed on the basis of comprehending their signatures in the GPR sections. The magnetic results have improved the identification of some objects revealed by the GPR and provided ideas about some of the other features.

The heterogeneous nature of the earth has given rise to variations experienced in the subsurface. Some parts are good for hydrological exploration while others are good for civil engineering activities. These variations experienced in the subsurface could not be detected except through geophysical survey and analysis. Integration of ground magnetic and Vertical Electrical Sounding (VES) techniques were carried out in Awgbagba to image the subsurface fabric with a view to mapping subsurface geological features, such as the weak and competent zones, to determine the overburden thickness, and suitability of Awgbagba for civil engineering and hydrogeological purposes. Ten ground magnetic traverses were established in WE and N-S azimuths. Twenty VES points were randomly sounded for the study in order to cover the entire study area. The magnetic residual field anomaly values ranged from-1, 600 to 700 nT. The study area is grouped into low, average, and high magnetic zones. The depth to magnetic sources ranged from 8.1 to 48.9 m with a mean value of 17.4 m. Three planar feature orientations in the study area are in NE-SW, NW-SE, and SE-NW orientations. VES results showed 7 QH-curve type, 6 HA-curve type, 4 KH-curve type, 1 AA-curve type, 1 HK-curve type and 1 QQ-curve type respectively. The ratio of thin-to-thick overburden and fresh-to-fractured bedrock are 3:7 and 2:3 respectively. It is concluded that the study area cannot withstand high-rise building constructions. However, the mapped fracture zones in the study area would serve as promising zones for borehole development.

2D Electrical Resistivity Tomography (ERT) was carried out at the proposed Siktan Dam site, Erbil Governorate, NE Iraq. The aim of this study is to evaluating the geo-structural setting of the concealed bedrock along the proposed dam axis and the flanks of the proposed dam site. A comprehensive geotechnical investigation consisting of borehole drilling works and electrical resistivity data were carried out to investigate the subsurface formation. Geologically the proposed dam site is located on the Shiranish Formation consisting of dark gray claystone alternating with limestone marlstone and sandstone. Three profiles were taken by Wenner array with 48 electrodes along of each profile which equal 235m, the space between electrodes is 5m. The SYSCAL PRO instrument is used to collect resistivity data and (SYSCAL Switch) were used with 48 electrodes along one line, and which carries out an automatic switching of these electrodes for acquiring profiling data. The data were processed and interpreted by applying 2D inversions TomoLab software. The using of geophysical prospecting in geotechnical investigation is sometimes looked at as a probable rather than certain method when it comes to construct a detailed subsurface layer profiles. The correlation between borehole information and electrical resistivity ranges was done. The combination of geophysical and geotechnical data may greatly improve the quality of buildings construction in civil engineering. From the structural point of view there is no faults have been detected in this location from ERT and boreholes data as well as there is no evidence of the existence of cavities or any other risky resources. The results indicate that the proposed site is suitable for construction of the dam. Boreholes and geotechnical investigations successfully used to verify the results of the resistivity measurements results.

The article summarizes the experience of processing and interpreting the data of engineering seismic survey performed for the state of the soil railway embankment studying in permafrost. The engineering-geological prerequisites for the use of seismic survey are considered, factors affecting the roadbed deformation are indicated. According to seismic data, the embankment was divided into layers, the seismic properties of the soils (the velocities of P- and S- waves) were determined.

FOR CITATION:
SALEM, Hilmi S., 2000. The Compressional to Shear-Wave Velocity Ratio for Surface Soils and Shallow Sediments. European  Journal of Environmental and Engineering Geophysics. 2000 (December), Vol. 5, Issue: 1, Pages: 3-14 (12p).

ABSTRACT:
The compressional to shear-wave velocity ratio, or velocity ratio (Vp/Vs), is an effective parameter in describing various physical parameters and lithological attributes of porous media, as well as the nature and kind of saturant filling the pores. In this study, Vp/Vs was obtained for surface soils and glacially originated shallow sediments (northern Germany), using in-situ seismic refraction measurements. For the whole column of the soils and sediments investigated, Vp/Vs lies in a general range of 1.28-3.19, with an average value of 2.42. The Vp/Vs shows considerable variations for the direct waves propagating through the surface soils saturated with air, and for the waves refracted from the underlying sediments that are partially or totally saturated with water. The Vp/Vs value of 2 is remarkable in discriminating between the partially and totally saturated sediments. The heterogeneity of the soils and sediments, vertically and laterally, and the variations in porosity, mineralogical composition, grain size, degree of saturation and kind of saturant (air or water) are primary factors responsible for the Vp/Vs varions. Direct relationships between Vp/Vs, on the one hand, and the compressional wave velocity and the shear wave velocity, on the other, and an inverse relationship between Vp/Vs and porosity, were obtained with coefficients of correlation ranging from 0.87 to 0.92.

KEYWORDS: Compressional to Shear Wave Velocity (Vp/Vs); Seismic Refraction Measurements; Surface Soils and Shallow Sediments; Porosity; Lithology; Air and Water Saturations.

The Nuclear Magnetic Resonance is an analytic technique which is acquiring importance in the farmochemistry industry, given its versatility and advantage in respect to other techniques that require of a standard. In this work we report the employment of this technique to establish the identity and integrity of drugs like Captopril, Ibuprofeno in tablets and Diclofenac in tablets and ampoules; the total composition of the medicines and the preliminary stability study of Captopril tablets and Omeprazol capsules.

The ability to predict the geotechnical properties of subsurface soils using non-invasive geophysical measurements can be undeniably useful to the geotechnical engineer. Using laboratory data, we assess the potential of artificial neural networks to investigate the relations between geotechnical and electrical parameters characterizing a variety of soils. The geotechnical parameters are: fines content, mean grain size, mean pore size and the specific surface area. The electrical parameters obtained from low-frequency electrical measurements (4 Hz) include the resistivity amplitude, phase shift and the loss tangent. Relations that can be used to predict the geotechnical parameters of a soil given its electrical parameters are developed. The predictive capabilities of the neural networks are compared with traditional multivariate regression models. The performances of the neural network and regression models in predicting (a) the geotechnical parameter given the same electrical parameters as inputs and (b) the electrical parameters given the same geotechnical parameters as inputs are compared. In both cases, the neural network outperforms the multivariate regression as the neural network is able to capture and model the non-linear and complex relationships among the variables. The relative importance of the geotechnical parameters on the overall electrical conduction was examined using the neural networks. The results indicate that mean grain size and fines content are the two geotechnical parameters that influence phase-shift values the most; fines content and mean pore size influence the resistivity amplitude the most, whilst fines content and mean grain size influence the loss tangent the most. It was observed that of the four geotechnical parameters, the mean grain size influences the measured resistivity values the least.

The Ground Probing Radar (GPR) is a valuable tool for near surface geological, geotechnical, engineering, environmental, archaeological and other work. GPR images of the subsurface frequently contain geometric information (constant or variable-dip reflections) from various structures such as bedding, cracks, fractures etc. Such features are frequently the target of the survey; however, they are usually not good reflectors and they are highly localized in time and in space. Their scale is therefore a factor significantly affecting their detectability. At the same time, the GPR method is very sensitive to broadband noise from buried small objects, electromagnetic anthropogenic activity and systemic factors, which frequently blurs the reflections from such targets.

This paper introduces a method to de-noise GPR data and extract geometric information from scale-and-dip dependent structural features, based on one-dimensional B-Spline Wavelets, two-dimensional directional B-Spline Wavelet (BSW) Filters and two-dimensional Gabor Filters. A directional BSW Filter is built by sidewise arranging s identical one-dimensional wavelets of length L, tapering the s-parallel direction (span) with a suitable window function and rotating the resulting matrix to the desired orientation. The length L of the wavelet defines the temporal and spatial scale to be isolated and the span determines the length over which to smooth (spatial resolution). The Gabor Filter is generated by multiplying an elliptical Gaussian by a complex plane wave; at any orientation the temporal or spatial scale(s) to be isolated are determined by the wavelength.λ of the plane wave and the spatial resolution by the spatial aspect ratio γ, which specifies the ellipticity of the support of the Gabor function. At any orientation, both types of filter may be tuned at any frequency or spatial wavenumber by varying the length or the wavelength respectively. The filters can be applied directly to two-dimensional radargrams, in which case they abstract information about given scales at given orientations. Alternatively, they can be rotated to different orientations under adaptive control, so that they remain tuned at a given frequency or wavenumber and the resulting images can be stacked in the LS sense, so as to obtain a complete representation of the input data at a given temporal or spatial scale.

In addition to isolating geometrical information for further scrutiny, the proposed filtering methods can be used to enhance the S/N ratio in a manner particularly suitable for GPR data, because the frequency response of the filters mimics the frequency characteristics of the source wavelet. Finally, signal attenuation and temporal localization are closely associated: low attenuation interfaces tend to produce reflections rich in high frequencies and fine-scale localization as a function of time. Conversely, high attenuation interfaces will produce reflections rich in low frequencies and broad localization. Accordingly, the temporal localization characteristics of the filters may be exploited to investigate the characteristics of signal propagation (hence material properties). The method is shown to be very effective in extracting fine to coarse scale information from noisy data and is demonstrated with applications to noisy GPR data from archaeometric and geotechnical surveys.

The strength and stability conditions of unconsolidated geo-materials, for example soils, are influenced by modifications of their micro-structure, texture, mineralogy and effective stress levels. These modifications in the internal structures of the soils often result in geohazards (e.g., landslides, liquefaction, debris flow), which often claim so many lives, destroy the environment, and cause considerable amounts of property damage. Characterization and monitoring of such geohazards demand knowledge about the geotechnical (physical and mechanical) properties of unconsolidated near-surface geo-materials of interest. The fundamental relations between geo-electrical parameters and the geotechnical properties that influence the mechanical behavior of soils are investigated by performing controlled laboratory experiments on sand-clay mixtures under stress. Spectral electrical response (SER) measurements are performed on these mixtures over a range of frequencies [Formula: see text] wi...

Two dimensional Electrical Resistivity Tomography (ERT) method was used to investigate a Dam site in Shaqlawa-Erbil Governorate, NE Iraq, to delineate the nature of the subsurface structures to assess its suitability for the construction of dam. The main objectives are to investigate the depth to the bedrock, possible geologic structures, such as possible presence of faults, fractures, voids and clay in the dam axis and abutments. The selected method has the possibility to give an image of the subsurface and map lateral and vertical variations in the subsurface geology of the site. For this purpose, the (SYSCAL Switch and SYSCAL Pro Switch units) equipment was used with Wenner array (48 electrodes). Three 2D electrical resistivity tomography profiles were conducted, the space between electrodes is 5m and the length of the profiles are 235 m. The depth of the investigation is assumed to be 40 m. The acquired data were inverted to tomogram sections using tomographic inversion by using...

Two geophysical methods were used for mapping the archaeological features at Qantir village: magnetic and resistivity surveys. The magnetic survey was carried out before the resistivity survey in order to evaluate the distribution of hidden archaeological features and cultural relics. It was conducted over an area of 120 ð 100 m using a fluxgate gradiometer (Geoscan FM36) that measures the vertical gradient of the geomagnetic field. The readings were logged every 0.5 m along 20 m, zigzag traverses. The resultant data were processed and treated to produce a high-quality magnetic image. The final magnetogram and graphical interpretation plot show the distribution of high and low magnetic features that reflect the buried archaeological and non-archaeological features. Subsequently, a resistivity survey was carried out over interesting areas identified from the initial results of the magnetogram. Four Wenner profiles were also measured, named P1W, P2W, P3W and P4W. The minimum electrode spacing used through all the profiles was 1 m and the maximum electrode spacing varied from one profile to another according to its length. These data were used to construct four apparent resistivity pseudosections. A comparison between the magnetic vertical gradient profile and resistivity inverse models was performed in order to check the value of using the Wenner configuration in parallel with the gradiometer survey. The geophysical investigation mapped some archaeological features with a high probability of indicating the presence of storage and burial chambers, bisecting walls, ditches and streets.

The strength and stability conditions of unconsolidated geo-materials, for example soils, are influenced by modifications of their micro-structure, texture, mineralogy and effective stress levels. These modifications in the internal structures of the soils often result in geohazards (e.g., landslides, liquefaction, debris flow), which often claim so many lives, destroy the environment, and cause considerable amounts of property damage. Characterization and monitoring of such geohazards demand knowledge about the geotechnical (physical and mechanical) properties of unconsolidated near-surface geo-materials of interest. The fundamental relations between geo-electrical parameters and the geotechnical properties that influence the mechanical behavior of soils are investigated by performing controlled laboratory experiments on sand-clay mixtures under stress. Spectral electrical response (SER) measurements are performed on these mixtures over a range of frequencies (0.001 Hz–1 kHz) with concurrent measurements of their geotechnical properties. Electrical parameters, such as phase, resistivity amplitude, capacitance, and loss tangent, are extracted from the SER measurements, and geotechnical properties of the mixtures, which include void ratio, dry density, and the modulus of elasticity, are obtained from laboratory measurements. Cross-plots of geotechnical properties and geo-electrical parameters indicate significant correlations. The phase and capacitance values decrease with an increase in the dry density, whilst the loss tangent and the resistivity values increase with increase in dry density. The phase and capacitance values, however, decrease with an increase in the values of the modulus of elasticity, whereas the loss tangent and the resistivity values increase with increase in elastic modulus. These relations can be useful in non-invasive prediction of the physical, mechanical, and geotechnical properties of unconsolidated geo-materials relevant in the assessment, monitoring, and mitigation of geohazards.

The ability to predict the geotechnical properties of subsurface soils using non-invasive geophysical measurements can be undeniably useful to the geotechnical engineer. Using laboratory data, we assess the potential of artificial neural networks to investigate the relations between geotechnical and electrical parameters characterizing a variety of soils. The geotechnical parameters are: fines content, mean grain size, mean pore size and the specific surface area. The electrical parameters obtained from low-frequency electrical measurements (4 Hz) include the resistivity amplitude, phase shift and the loss tangent. Relations that can be used to predict the geotechnical parameters of a soil given its electrical parameters are developed. The predictive capabilities of the neural networks are compared with traditional multivariate regression models. The performances of the neural network and regression models in predicting (a) the geotechnical parameter given the same electrical parameters as inputs and (b) the electrical parameters given the same geotechnical parameters as inputs are compared. In both cases, the neural network outperforms the multivariate regression as the neural network is able to capture and model the non-linear and complex relationships among the variables. The relative importance of the geotechnical parameters on the overall electrical conduction was examined using the neural networks. The results indicate that mean grain size and fines content are the two geotechnical parameters that influence phase-shift values the most; fines content and mean pore size influence the resistivity amplitude the most, whilst fines content and mean grain size influence the loss tangent the most. It was observed that of the four geotechnical parameters, the mean grain size influences the measured resistivity values the least.

The ability to predict the geotechnical properties of subsurface soils using non-invasive geophysical measurements can be undeniably useful to the geotechnical engineer. Using laboratory data, we assess the potential of artificial neural networks to investigate the relations between geotechnical and electrical parameters characterizing a variety of soils. The geotechnical parameters are: fines content, mean grain size, mean pore size and the specific surface area. The electrical parameters obtained from low-frequency electrical measurements (4 Hz) include the resistivity amplitude, phase shift and the loss tangent. Relations that can be used to predict the geotechnical parameters of a soil given its electrical parameters are developed. The predictive capabilities of the neural networks are compared with traditional multivariate regression models. The performances of the neural network and regression models in predicting (a) the geotechnical parameter given the same electrical parameters as inputs and (b) the electrical parameters given the same geotechnical parameters as inputs are compared. In both cases, the neural network outperforms the multivariate regression as the neural network is able to capture and model the non-linear and complex relationships among the variables. The relative importance of the geotechnical parameters on the overall electrical conduction was examined using the neural networks. The results indicate that mean grain size and fines content are the two geotechnical parameters that influence phase-shift values the most; fines content and mean pore size influence the resistivity amplitude the most, whilst fines content and mean grain size influence the loss tangent the most. It was observed that of the four geotechnical parameters, the mean grain size influences the measured resistivity values the least.

A continuous global positioning system station (CGPS) provides accurate coordinate time series, while episodic GPS stations (EGPSs), which operate throughout short measurement sessions, are generally used to improve the monitoring spatial density. In an urban environment, EGPSs are typically equipped with removable mounts (topographical tripod or bipod). In this paper, a method is proposed to evaluate vertical surface motions by

Integrated coplanar loop electromagnetic conductivity method, electrical resistivity tomography (ERT), and Schlumberger vertical electrical sounding (VES) methods were deployed to investigate the nearsurface crustal architecture and geohydrodynamics of the crystalline basement terrain of Araromi, Akungba-Akoko, Ondo State, southwestern Nigeria. The study aimed at understanding the spatial distributions of groundwater, and soil moistures with exhumed crustal structures, to alleviate groundwater deficit, and the failure of engineering structural foundations in this area. Six geophysical survey traverses of varying lengths were explored, with eight VES stations selected for further investigations on the lithostratigraphic model for constraint and deeper probing. The measured conductivities over the study area varied in the range of 3.0-35.19 mS/m. The results coincided with the ERT responses for the motley topsoil, clayey to sandy weathered strata, partially weathered/fractured bedrock, and fresh gneissic bedrock. A, AK, HA, and KQ types of curves pictured the varying depths of the deep-weathered troughs, and the fractures (i.e., F1 to F21), arising from the prevalent intense metamorphism and progressive weathering in the area. The geohydrodynamic systems of the study area's crustal architecture were attributed to water-rock interactions within the geologic structures. Also, the depths of the fractured zones extending more than 52 m in some sections enhanced the spatial groundwater storage, despite the thin overburden (i.e., <4 m). The residual soils' water retention is credited to clayey soils from the rich feldspathic bedrock. Hence, the results obtained suggest that intended wells and boreholes should take advantage of the deep-weathered and fractured zones, with average depths of 11 m and >39 m, respectively, to ameliorate the deficit of groundwater supply in the area. Furthermore, failures of engineering structural foundations are likely to occur at highly conductive sections (i.e., >20 mS/m), oscillating bedrock surfaces, floating boulders, and stiffer soils under incompetent strata, and conductive thin and large-size apertures. The study demonstrated the advantages of integrating multi-geophysical methods of data collection and analysis.

One-page abstract deadline: Oct. 31, 2019
Full chapter deadline: Jan. 31, 2020

We cordially invite you and your relevant colleagues to join us in a new Open Access book project. In collaboration with Knowledge Unlatched, IntechOpen will publish an open access book "Applied Computational Near-surface Geophysics – From Integral and Derivative Formulas to MATLAB codes " (ISBN: 978-1-83962-229-8) with me appointed as the editor.

IMPORTANT: If your peer-reviewed submission is accepted, the open-access publishing fee will be covered by the publisher in collaboration with KU, so there will be no fee for your chapter.

The book will cover the following chapters:
Chapter 1. Reviewing required mathematics with MATLAB
· Matrices
· MATLAB syntax
· Import-export files
· Finite difference method
· Fourier analysis
· Inverse method
Chapter 2. Refraction seismology
Chapter 3. Reflection
Chapter 4. Cross/Down/up-hole seismic methods
Chapter 5. Multi-channel surface wave analysis (MSWA)
Chapter 6. Gravity
Chapter 7. Resistivity
Chapter 8. Electrical resistivity tomography
Chapter 9. Magnetic
Chapter 10. Electro-magnetic
Chapter 11. Ground-penetrating radar (GPR)
Or other chapters that you think can fit under the mentioned title.

The first step is to register on the following link:

https://mts.intechopen.com/welcome/38cdbbb671df620b36ee96af1d9a3a90/

and submit a short chapter proposal (Maximum one page i.e. an abstract consists of your point of view, strategy, etc., and keywords) by October 31, 2019, so that we can get an idea of what you would focus on in the full chapter.

The full chapter the deadline will not be until January 31, 2020, so there is plenty of time for you to prepare it.
Once you have registered, you will have an IntechOpen Author service manager at your disposal who will lead you through the process, while we review proposals and later full chapters.

Please reply to my email (aghayan@okstate.edu) and inform me of your participation in the following week, if possible, so that I can make plans for the book. If you should have any questions, I will be happy to assist.
Best wishes,

Khuff Formation is of utmost importance in Saudi
Arabia for oil and gas reservoir although it is composed mainly
of limestone. This reason refers to the existence of intensive
fractures which play a vital role in the increase in porosity and
permeability of this formation. The fracture pattern in the
study area was verified through 2D and 3D ground penetrating
radar (GPR)-defined and electrical resistivity tomography
(ERT)-defined surveys. In this respect, ten of 2D GPR surveys
were collected along an intersected grid of profiles covering
the study area while ERT data were collected along three
profiles of the GPR grid. The results were interpreted in light
of the field-based structural and stratigraphic assessment of
the outcropping rocks. The analysis of the inverted ERT and
filtered GPR sections revealed the presence of fractures.
Several resistivity and electromagnetic reflection anomalies
were laterally and vertically identified across the measured
sections clarifying fractures that extend to a depth of 24 m in
the limestone. Most fractures are oriented vertical to subvertical
dipping both east-west and north-south.

Egyptologists have suggested there might be a hidden extension of the Karnak Temple, located in the Luxor governorate of Egypt. They believe that the temple contains some buried sections on its northern and eastern sides. During January and September 2002, ground-penetrating radar (GPR) and magnetic surveys were carried out on an 80 40 m area near the eastern gate. The GPR data did not give a clear picture of some of the buried features. A clearer identification of the hidden features was accomplished by interpretation of the magnetic data using the analytic signal approach. Our study has revealed the presence of coffin-and tomblike structures built of mud bricks. Limestone blocks were also detected, which may be attributable to destroyed pillars or statues.

Introduction Archaeological Geophysics lab of Department of Physics of Sofia University is the only one in Bulgaria which develops new geophysical methods and equipment for study of archaeological objects and their dating (Shopov et al., 1993, Dermendjiev et al, 1996). This lab has equipment and specialists for using of broad range of archaeogeophysical methods. Here we demonstrate possibilities of these techniques for solving of various archaeological tasks.

Archaeogeophysical Methods This lab uses following archaeogeophysical methods for exploration and non- destructive investigation of archaeological objects:
I. Radar Methods
1. Ground penetrating radar (GPR) – This method was developed by NASA to study the lunar ground. Introduction of these space technology to archaeology makes GPR the most powerful archaeogeophysical technique (Conyers, 2004), but interpretation of GPR data is most complicated and requires very complex data computing. It is the most complicated and complex archaeogeophysical technique. GPR allows registration of so fine archaeological objects that are hard to see by eye and can be missed during archaeological excavations (Conyers, 2004).
Advantages: а. GPR is the only archaeogeophysical method which allows preparation of 2D slices (maps) of underground objects from various depths under the surface without their excavation (Conyers et al., 2004), (fig.1).
b.It is the only archaeogeophysical method which allows preparation of 3D reconstructions of the precise shapes and depths of underground objects (Conyers et al., 2004), (fig.2).
c.It allows precise determination of depths of the underground objects under the surface.
d.It allows visualization of the underground objects as radar images in real time during the measurements.
e.It allows simultaneous geophysical exploration and archaeological excavation of the registered anomalies.
f.It has highest resolution from all geophysical techniques.
g.It can be used for scanning of vertical walls and localization of unhomogeneities in it.
h.Registered signal can undergo further computing for extraction of invisible details from the raw scan and graphic display of the results.
i.It allows fast scanning of large area. It is effective for large scale exploration with high horizontal resolution.
j.It allows connecting of different archaeological excavations by GPR exploration of the space between them.
k.GPR exploration can be done through ice, asphalt, concrete etc. (Archaeological Geophysics lab website, 2007).
l.On rough terrains can be done step-by-step measurements which allows deeper penetration of the radar signal.
Disadvantages: а. Interpretation of the signal is extremely complicated (Conyers, 2004) and requires years of experience of GPR studies of archaeological sites.
b.Very high cost of the equipments.
c.It can not be used in conductive environment (like sea water) or salty soils.
d.Limited penetration depth which depend on the soil humidity. Usually it varies from 1 meter in wet soil to 17 m in buildings (Archaeological Geophysics lab website, 2007)
e.Archaeological applications of GPR require an expert of very unusual training in specific fields of geophysics, geology and statistical physics. Experience in other GPR applications can not be applied on archaeological sites and experts on them can not be easily trained in archaeological applications of GPR
GPR applications in archaeology (Archaeological Geophysics lab website, 2007) are nondestructive localization and mapping of cultural layers in following buried archaeological objects:
-tombs and burials
-tunnels, catacombs, mud- huts and underground channels
-walls of buildings
-fire places
-metal and ceramic artifacts and coatings
-cavities and defects in buildings
-caves, bunkers, caverns and karstic futures
-underground reservoirs and buried pipes.
Nondestructive stratification of:
-sediments, river and lake deposits;
-soil layers including ancient arable lands;
-water table;
-faults and land slides.
Nondestructive study and monitoring of archaeological objects, cultural heritage and underground communications.

Experimental part
Calibration Experiments: Large numbers of calibration experiments were made inside the building of Department of Physics of Sofia University (fig.3) and surrounding grounds with known underground communications (pipes, canals, tunnels, etc) before the start of the field GPR measurements. They demonstrated that this equipment works perfectly on open ground and inside buildings and visualize all known futures of the studied terrains (fig.3, 4). It can work 17 meters deep in dry environment (fig.4). This depth is 70 % deeper than the claims of the producer of this GPR unit and antenna.
GPR measurements of Bulgarian archaeological sites. 
First GPR measurements on Bulgarian archaeological site (fig.5) were made in 2007 in the tomb “Golyamata Kosmatka“ (Shopov, in press). 60 scans of the walls and floor of the tomb were measured with resolution varying from 1,3 to 1,7 cm. Four groups of 5 parallel scans each were measured on the walls of the tomb on height from 0 to 250 cm. They were summed in a 3D data base. Then it was sliced in 15 slices (fig.6) of 20 nanoseconds (corresponding to a thickness of 75 cm if the radar beam pass through soil but to 3 m through air)
Obtained slices have resolution of 0.1 m. in horizontal, but 0.5m. in vertical direction. Scanned tomb camera was round, so obtained slices are segments of a circle (fig.6). So obtained 2D maps looks as prints of cylindrical seals (fig.5). They demonstrate that second unexcavated camera is located behind the west wall of the tomb. It is twice bigger than the camera in the excavated tomb.Scans of the walls of the tomb in the lowest scanning position suggest that the radar radiation penetrates trough homogeneous material (Fig. 7.А) at least 16 meters in all directions. Material of the walls is granite. It means that the whole tomb is embedded at least 50 centimeters deep in a granite square at least 35 meters in diameter. This does not mean that the square is circled. It can be extended in all directions but radar radiation can not reach its edges. The soil filling of the mound is detected through the granite wall of the tomb (Fig. 7.B) everywhere at over 50 cm above the floor.

GPR measurements of prehistoric archaeological sites. 
Prehistoric sites are the most difficult archaeological objects for archaeogeophysical survey due to lack of metal objects in them. Most of the artifacts have the same chemical composition and physical properties as the surrounding ground. Especially stone artifacts have same properties as stones aground. So GPR is the most appropriate archaeogeophysical technique for survey of Neolithic settlements (fig.8) and is the only one usable for survey of Paleolithic sites.
GPR is most suitable geophysical technique for solving of most of the tasks of archaeological exploration. Before its development it was considered impossible to locate underground objects like plastic, terracotta, concrete and asphalt. GPR became the main technique for localizing and mapping of non-conductive, non-metal and non-magnetic objects. It can be used even for exploration of under-water objects in fresh water basins (Archaeological Geophysics lab website, 2007).Therefore in the last years it is the main focus of work of Archaeological Geophysics lab of Sofia University.

II. Electrical resistivity methods.
2. Electrical profiling. It measures profiles of the electric resistivity (fig.9). It allowed deepest geophysical exploration of a Bulgarian archaeological site at 19 meters below the surface (Shopov, 2007) but such measurements can be done even on 40 m. depth. It is most appropriate for searching of tombs, caves, tunnels or bunkers.
3. Vertical Electrical Probing- detects the same objects as electrical profiling serving for determination of the depth of the detected anomalies.
4. Electrical tomography (continuous electrical probing)- allows visualization of anomalies of the electric resistivity and of the objects creating it.
Although its great depth of operation these methods are extremely slow, laborious and expensive, have many limitations and interferences. So now Archaeological Geophysics lab abandons these methods except of Vertical Electrical Probing which sometimes can help GPR for determination of the depth of the detected anomalies.
III. Induction methods- use military technologies for location of mines.
5. Pulse induction- Allows localization of large metal objects on depth up to 6 meters. Its equipment emits powerful electromagnetic pulses and measures the inducted current in the underground objects between the pulses (Aittoniemi et al., 1986).  It works through walls and stones. It allows very fast scanning and high precession of localization of the objects, but it doesn’t allow precise determination of the depth of the anomalies. Underground cables, rebar or metal nets mask objects and make impossible its use.

6. Electromagnetic Induction- Allows precise localization of small metal objects and determination of the metal building them by its conductivity (Gardiner, 1967). Works on shallow depth which varies from 0.3 up to 1 meter depending on the size of the found object. Its equipment emits electromagnetic field and measures the inducted current in the underground objects passing between its coils. It doesn’t allow determination of the depth of the anomalies. Underground cables, rebar or metal nets mask objects and make impossible its use.

We have investigated the influence of petrophysical and geotechnical engineering properties of unconsolidated near-surface geomaterials (soils) on their electrical responses or measurements. Complex resistivity measurements were performed at a constant effective stress on 32 samples of varying textures and compositions. Petrophysical and engineering properties that inherently affect the mechanical and strength behavior of the samples — that is, fines content, pore-size parameter, specific surface area, and fractal dimension of the grain-size distributions — were obtained from geotechnical analysis. The electrical parameters that describe the electrical response of the samples — that is, resistivity amplitude [Formula: see text], phase shift [Formula: see text], percent frequency effect (PFE), loss tangent [Formula: see text], and the normalized phase [Formula: see text] — are computed from the electrical measurements. Crossplots of the electrical and engineering parameters provide u...

Egyptologists have suggested there might be a hidden extension of the Karnak Temple, located in the Luxor governorate of Egypt. They believe that the temple contains some buried sec-tions on its northern and eastern sides. During January and September 2002, ground-penetrat- ...

Integrated surface geophysical methods were used in investigating causes of pavement instability along a portion of Akure-Owo expressway, southwestern, Nigeria. The methods comprise of ground magnetic profiling, Very Low Frequency Electromagnetic (VLF-EM) profiling and geoelectric sounding. The magnetic profile shows a drop below 31500nT at distance 100m and above 32500nT at distances 140 and 310m, these drops in value could correspond to lithological contacts or bedrock depressions. The combined plots of raw real and filtered real VLF-EM data show conductive zones at distances 70m, 230-240m and 350-360m, which could be indicative of fractured zones or conductive clay materials. The 2-D geoelectric section shows bedrock depressions at distance 80-160m (stable segment) and 240-360m (unstable segment), while bedrock fractures was delineated beneath VES points 1, 3, 5 and 10, corresponding to distances 0, 80m, 160m and 400m respectively. The topsoil resistivity varies from 83 to 865 ohm-m, while resistivity in the weathered layer materials ranges from 182-1139ohm-m along the stable segment and 27-262ohm-m along the unstable segment. The low resistivity values observed beneath the unstable segment are typical of expansive clay. Thus the instability of the road pavement along the studied portion of the road is probably precipitated by the presence of near surface bedrock depressions, occupied by low resistivity weathered materials, typical of expansive clay and sandy clay, adjudged unsuitable construction materials.

Integrated geophysical surveys including magnetometer, gradiometer and seismic refraction were performed in the Suchon area, Kongju, Korea, which revealed three locations of buried architectural features. The magnetometer survey identified four main anomalies that were further tested using the gradiometer. Application of the second vertical derivative and the high-pass filtering techniques to the magnetometer data isolated the deeper sources and enhanced the near-surface features. Depth was estimated using magnetometer data and seismic refraction analysis.The study identified three promising areas that are strongly recommended forexcavation, which can be seen in the northeastern and southwestern parts of the study area. They are strongly linked to shallow historical features , i.e. brick tomb structure, pottery collection and stone-mound tomb, that were dominant during Baekche rule in Suchon area and therefore are believed to be from the Baekche period.

Integrated geophysical surveys including magnetometer, gradiometer and seismic refraction were performed in the Suchon area, Kongju, Korea, which revealed three locations of buried architectural features. The magnetometer survey identified four main anomalies that were further tested using the gradiometer. Application of the second vertical derivative and the high-pass filtering techniques to the magnetometer data isolated the deeper sources and enhanced the near-surface features. Depth was estimated using magnetometer data and seismic refraction analysis.The study identified three promising areas that are strongly recommended forexcavation, which can be seen in the northeastern and southwestern parts of the study area. They are strongly linked to shallow historical features , i.e. brick tomb structure, pottery collection and stone-mound tomb, that were dominant during Baekche rule in Suchon area and therefore are believed to be from the Baekche period.