Electrical resistivity tomography (ERT) methods have been increasingly used in various shallow depth archaeological prospections in the last few decades. These non‐invasive techniques can save time, costs, and efforts in archaeological prospection and yield detailed images of subsurface anomalies. We present the results of quasi‐three‐dimensional (3D) ERT measurements in an area of a presumed Roman construction, using a dense electrode network of parallel and orthogonal profiles in dipole–dipole configuration. A roll‐along technique has been utilized to cover a large part of the archaeological site with a 25 cm electrode and profile spacing, respectively. We have designed a new field procedure, which used an electrode array fixed in a frame. This facilitated a very efficient field operation, and overall a total of 9648 electrode positions were occupied. The 3D ERT inversion results clearly characterize the main structures of the Roman foundations. We compared our high‐resolution 3D electrical resistivity model with findings from archaeological excavations, which have been done in some parts of the surveyed area. The ERT result coincide well with the excavation results, i.e. the location as well as the vertical and horizontal extensions of the structures could be precisely imaged. The ERT results successfully images most parts of the walls, pits and also smaller internal structures of the Roman building; moreover, excavation ditches that had been refilled prior to the ERT survey are delineated as resistivity heterogeneities as well.
Constructing a fine 3D geomodel for complex giant reservoir is a crucial task for hydrocarbon volume assessment and guiding for optimal development. The case under study is Mishrif reservoir of Halfaya oil field, which is an Iraqi giant carbonate reservoir. Mishrif mainly consists of limestone rocks which belong to Late Cenomanian age. The average gross thickness of formation is about 400m. In this paper, a high-resolution 3D geological model has been built using Petrel software that can be utilized as input for dynamic simulation. The model is constructed based on geological, geophysical, pertophysical and engineering data from about 60 available wells to characterize the structural, stratigraphic, and properties distri
... Show MoreThe 2-D Resistivity imaging survey conducted within the desert area to meet the region's need of groundwater, due to the absence of any surface water, in addition, there are no any geophysical studies carried out previously. Ten point survey was performed to study the ground water aquifers in the southwest of Samawah city, Iraq. The length of the survey line in each point survey is 1200 meters by using 120 electrodes with 10 meters electrode spacing by applying Wenner-Schlumberger array. There are three main resistivity zones in the study area. The first resistivity zone ranging between 2.00-10.1 ohm.m, locate at shallow depth, represented Quaternary deposits. The second resistivity zone ranging between 22.8-51.3 ohm.m, it represents bea
... Show MoreConstructing a fine 3D geomodel for complex giant reservoir is a crucial task for hydrocarbon volume assessment and guiding for optimal development. The case under study is Mishrif reservoir of Halfaya oil field, which is an Iraqi giant carbonate reservoir. Mishrif mainly consists of limestone rocks which belong to Late Cenomanian age. The average gross thickness of formation is about 400m. In this paper, a high-resolution 3D geological model has been built using Petrel software that can be utilized as input for dynamic simulation. The model is constructed based on geological, geophysical, pertophysical and engineering data from about 60 available wells to characterize the structural, stratigraphic, and properties distribution along
... Show MoreBasal breccia unconformity layer between Anah and Euphrates Formations in Al-Haqlaniyah area, Western desert, include enormous sinkholes and cavities usually cause severe damages to any kind of engineering facilities built over it. Two-dimensional resistivity imaging has been applied to detect the depth and extent of the subsurface caves at five stations. The dipole-dipole array is chosen with an electrode spacing of 2 meters. 2D Dipole-dipole imaging inverse models show the resistivity values have a big variation between the anomalous background resistivity of rocks and part of cavities. These models showed shallow cavities at 1 to 3 m depth and others at 5to 6 m depth and extending to a depth of 23 m. The unconformity layer
... Show MoreThis paper presents a new and effective procedure to extract shadow regions of high- resolution color images. The method applies this process on modulation the equations of the band space a component of the C1-C2-C3 which represent RGB color, to discrimination the region of shadow, by using the detection equations in two ways, the first by applying Laplace filter, the second by using a Kernel Laplace filter, as well as make comparing the two results for these ways with each other's. The proposed method has been successfully tested on many images Google Earth Ikonos and Quickbird images acquired under different lighting conditions and covering both urban, roads. Experimental results show that this algorithm which is simple and effective t
... Show MoreThe 2D imaging survey was carried out using Wenner-Schlumberger array through (11) 2D survey lines distributed within and out of Abu-Jir fault zone, Southwest of Karbala City, central Iraq. The aim is to delineate subsurface fractures density. The total length of each 2D survey line is (600m.) with the unit electrode spacing (a) equals to (10m.).The results showed two types of fractures zones. The first type is formed by dissolution process of carbonate rocks, while the second fractures zone is formed from tectonic movements, and it includes two types of fractures system, oblique and vertical fractures.
This study includes comparison between subsurface fracture density within and out of Abu- Jir fault zone. This comparison showed that
The electrical resistivity method is one of the geophysical methods for detecting weak subsurface zone. The 2D resistivity data were used to compare three electrode configurations, Wenner, Dipole-dipole, and Schlumberger, to detect weak subsurface zones along a profile south of Baghdad near the Bismayah pumping station. The results show many zones of low resistivity that may be weak zones. A dipole-dipole array is a large number of measurements and is more sensitive than others. The Wenner-Schlumberger array has a depth also higher than other arrays. Wenner array has higher signal strength than other arrays. Because it is more sensitive to horizontal and vertical structures, the dipole-dipole array is the optimum for mapping sub
... Show MoreElectrical resistivity methods are one of the powerful methods for the detection and evaluation of shallower geophysical properties. This method was carried out at Hit area, western Iraq, in two stages; the first stage involved the use of 1Dimensional Vertical Electrical Sounding (VES) technique in three stations using Schlumberger array with maximum current electrodes of 50m. The second stage included the employment of two dimension (2D) resistivity imaging technique using dipole-dipole array with a-spacing of 4m and n-factor of 6 in two stations. The 1D survey showed good results in delineating contaminated and clear zones that have high resistivity contrast. Near the main contaminated spring, the 2D resi
... Show MoreDEMs, thus, simply regular grids of elevation measurements over the land surface.The aim of the present work is to produce high resolution DEM for certain investigated region (i.e. Baghdad University Campus\ college of science). The easting and northing of 90 locations, including the ground-base and buildings of the studied area, have been obtained by field survey using global positioning system (GPS). The image of the investigated area has been extracted from Quick-Bird satellite sensor (with spatial resolution of 0.6 m). It has been geo-referenced and rectified using 1st order polynomial transformation. many interpolation methods have been used to estimate the elevation such as ordinary Kriging, inverse distance weight
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