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The upward continuation technique was applied to the gravity and magnetic data to obtain the residual anomalies maps in eastern Iraq. A new processing method is introduced to calculate the crustal layers depending on the relation between the total range of the residual anomalies of gravity, magnetic data and the upward continuation, with multi-elevations. The significant relationship shows slope variations, which may reflect the maximum contrast in the physical properties (density and/or susceptibility) and the intersection point representing the depth of layer contacts. This method was applied to the eastern central part of Iraq, adjacent to the Iranian borders. It is found that the average depth range to the Jurassic formations, top basement rocks, transition layer (Curie point), and Moho discontinuity are 3.1- 4.8 km, 8-12.9 km, 20.9-22.4 km and 43.6 km, respectively. The Sedimentary cover in the study area ranges from 8 to 13 km. The maximum depth to the Moho discontinuity obtained by gravity data in the study area is 43.6 km. The radially average power spectrum technique was applied in the study area to calculate the gravity depth and magnetic sources' depth. Three depth levels of sources from gravity and magnetic data were obtained. These depths are shallow sources, average basement rock and deep sources (Moho) at 3km, 13.2-12.1 km, and 32.2-34km, respectively. The obtained results concerning the main layers in the crust were compared between the two methods, and the new method shows more reliable results. The detected depth levels refer to top Jurassic, basement rocks, and Moho discontinuity. The new method is believed to be used to detect the crustal layers depth with good results. [ABSTRACT FROM AUTHOR]

We numerically investigate the mechanisms that resulted in induced seismicity occurrence associated withCO2 injection at the Illinois Basin-Decatur Project (IBDP). We build a geologically consistent model that honors key stratigraphic horizons and 3D fault surfaces interpreted using surface seismic data and microseismicity locations. We populate our model with reservoir and geomechanical properties estimated using well-log and core data. We then performed coupled multiphase flow and geomechanics modeling to investigate the impact of CO2 injection on fault stability using the Coulomb failure criteria. We calibrate our flow model using measured reservoir pressure during the CO2 injection phase. Our model results show that pore-pressure diffusion along faults connecting the injection interval to the basement is essential to explain the destabilization of the regions where microseismicity occurred, and that poroelastic stresses alone would result in stabilization of those regions. Slip tendency analysis indicates that, due to their orientations with respect to the maximum horizontal stress direction, the faults where the microseismicity occurred were very close to failure prior to injection. These model results highlight the importance of accurate subsurface fault characterization for CO2 sequestration operations. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study focuses on the Late Palaeozoic development of the area east of Utsira High in the North Sea, where the stratigraphic section below the late Permian Rotliegend Group is undrilled. We use regional 3D seismic data to study structuring, sediment distribution and geomorphology across the Patch Bank Ridge and Utsira High in the North Sea. The results show that the Stord Basin and the bounding Utsira East fault initially developed during the Late Palaeozoic extension, probably during the Devonian, and that the Utsira Shear Zone controlled the location of Late Palaeozoic depocentres. The Patch Bank Ridge is an uplifted part of the Stord Basin where we identify Late Palaeozoic growth strata along the southern and northern flanks, indicating a similar timing of the structural evolution in this area. Two key wells, in the Sele High and Ling Depression, are used to relate a Late Palaeozoic isopach map with regional structuring, surface tilt and basement morphology to the enigmatic parts of the Late Palaeozoic basin system. Our results supplement regional models for the Late Palaeozoic basin development, we suggest that the deeply eroded Devonian half‐grabens preserved on the Utsira High formed parts of an extensive basin system that show stratigraphic expansion towards their bounding faults. The Top Basement surface at these highs offers several distinct geomorphologies that evolved during three periods of exposure, expressed as (i) a tilted and rugose landscape, (ii) distinct drainage networks and (iii) peneplain surfaces. Cover sediments place these landscapes to the (i) Devonian, (ii) Carboniferous/Permian/Triassic and (iii) Late Triassic periods. [ABSTRACT FROM AUTHOR]

In the present study, centrifuge tests for small-scale specimens were performed to investigate the dynamic soil pressure of the basement of buildings subjected to seismic ground motions. To investigate the effect of the embedded depth of basement, a deep basement model fixed to rock (model 1) and a shallow basement model embedded in soil (model 2) were tested. The soil pressures acting at the front wall (Dynamic soil pressure, DSP) and back wall (Soil pressure at back wall, BSP) were measured. Under the Northridge earthquake (with PGAb = 0.33 g), DSP of Model 1 (fixed based model) reached 100 kPa showing an increasing linear distribution from bottom to top. The DSP profile was similar to the profile of relative displacement between the basement and soil. Interestingly, BSP decreased to 0 as a gap occurred between the soil and basement wall. On the other hand, in the case of model 2 with a smaller depth, the relative displacement between the basement and soil was smaller due to the influence of flexible base. As a result, DSP (<20 kPa) was smaller and BSP was greater than those of the deep basement model fixed to rock. The tested soil pressures were compared with the predictions of existing models. [ABSTRACT FROM AUTHOR]

This study interprets gravity data in parts of southeastern Nigeria using spectral analysis and 2D modeling. The study area is bounded by Latitudes 5°N 30' to 6°N 30' and Longitudes 7°E 0' to 8°E 0'. The Bouguer gravity data was obtained from the Nigerian Geological Survey Agency (NGSA) in Geosoft grid file format. The study uses the spectral analysis method and 2D modeling with GM SYS to estimate the average depth of the sedimentary strata and the basement from the Bouguer anomaly map. The data sets cover the southern part of the Anambra basin and the northern Niger Delta complex. Regional-residual separation was applied to the Bouguer gravity data through the polynomial fitting of the first degree. This gave rise to the residual and regional maps. Further filtering actions accentuated the subtlest anomalies peculiar to the study area. Spectral analysis results reveal two depth models: deep source (D1) and shallow source (D2). The deep source represents depths within the basementrelated sources, while the Shallow source is associated with shallow-related gravity sources. D1 varies from 1.50 km to 4.02 km with an average value of 2.95 km, while D2 varies from 1.91 km to 0.514 km with an average value of 1.50 km. The thickest depth of the Modelled cross-section is at about 6845.62 m, which is within the tertiary recent sediment with clayey sands and shale extending beyond the study area. The average or actual sedimentary thickness of 2.95 km suggests that the area will be plausible for hydrocarbon exploration. The thickest sedimentary cover represents density variation in sedimentary rock of the basin, which occurs at the southern part of block 4 (Okigwe). [ABSTRACT FROM AUTHOR]

Objective: Iranian architecture has historically confronted various climatic challenges in desert regions, often leading to innovative solutions. One such challenge is the increase in temperature coupled with decreased relative humidity, particularly during the hottest days of the year. A sustainable climatic solution for achieving thermal comfort and mitigating harsh weather conditions in this region involves the integration of central courtyards and basements. However, the lack of moisture in the air renders the mere construction of these spaces insufficient for thermal comfort. To address this, pond spaces were incorporated into the yard and, in some cases, into the cellar or basement to help lower temperature and increase relative humidity. Method: This study employs descriptive and analytical methods alongside library and internet research. Additionally, simulation techniques were utilized to explore the impact of the pond factor within the two spaces of the cellar and yard. Results: The findings indicate that introducing a moisture source (pond) results in an average temperature reduction of up to 3.5 degrees Celsius in the yard and up to 2.5 degrees Celsius in the basement compared to scenarios without a pond on the hottest day of the year. Furthermore, the presence of a pond in the yard does not lead to significant changes in the temperature and humidity levels of the basement, even with air circulation. Conclusions: While the pond is essential for reducing the temperature of the yard itself and cannot be omitted from the design of desert homes, its role in enhancing thermal comfort within the cellar is particularly notable during peak heat hours. In the pond scenario, the temperature difference compared to the outside reaches approximately 9 degrees Celsius, whereas the scenario without the pond yields a difference of about 5 degrees. This underscores the undeniable importance of the water pond and the associated humidity in achieving thermal comfort.

The modern idea of the geological structure of oil deposits of the Nizhnechutinskoye field is presented. The uniqueness of the field lies in the shallow depths of productive deposits. The oil-saturated layer is 100 m. The shallow depths of productive formations led to low formation temperature and pressure. Under such conditions, oil is inactive, characterized by high viscosity, and dissolved gas is practically absent. The features of the formation of the sedimentary cover in the area of the field predetermined the block structure, while the rocks of the productive horizon are characterized by a complex system of vertical fractures, which greatly complicates the process of oil recovery. A distinctive feature of the studied section of the field is the presence of effusive rocks underlying the main productive stratum and overlapping the lower productive layer.The article systematizes the results of field trial operation, which revealed a number of complicating factors, which is associated primarily with the uniqueness of the geological structure of the studied deposits. Despite the solid history of studying the Nizhnechutinskoye field, which has almost 300 years, given the negligible depth of productive deposits, oil production at this field still remains a difficult task.

Studies have been carried out to assess the qualitative features of fluids, aimed at identifying the regularities in the differentiation of the properties of naphthides during the formation of hydrocarbon deposits outside anticlinal structures. Due to the exhaustion of hydrocarbon reserves associated with anticlinal traps, the main attention is paid to the composition of fluids confined specifically to non-anticlinal structures – to traps of a combined structure. Physicochemical properties, trace element (TE) composition, phase states of naphthides in deposits affected by hypergenetic or catagenetic processes have been analyzed using specific examples; in regions with a possible additional inflow of hydrocarbons (Romashkino group of fields in the Republic of Tatarstan); in the crystalline basement of sedimentary basins. The results of the analysis make it possible to predict the characteristic features of fluids in traps of various types at certain levels of the processes of oil formation, secondary transformation and destruction of accumulations, mainly due to the tectonic regime of the sedimentary basin. With prolonged lateral migration, at great depths with good isolation from surface weathering agents, light oils, depleted in TE, more often of nickel specialization, are found in lithologically and stratigraphically screened traps, and gas condensate accumulations are possible. At shallow depths with poor regional or local seals, heavy, highly viscous hypergene-transformed oils, natural bitumens with high concentrations of industrially significant metals V, Ni, Co, Mo Cd, U were found in traps of pinch-out zones and various types of trap screening. tectonically-screened traps) with a multiphase filling of traps and, at the same time, the influence and inflow of deep ones, i.e. more catagenically transformed fluids, it is possible to detect light oils of the nickel type or gas condensates enriched with elements of “magmatic emanations” – As, Hg, Al, B, rare earth elements. Oils filling combined traps in the crystalline basement within platform oil and gas basins, as a rule, do not differ in their compositional peculiarities in comparison with oils in overlying or adjacent parts of the sedimentary section.

The Elbistan (Chardak) earthquake with magnitude Mw = 7.5 or 7.6 happened in Eastern Anatolia on 06.02.2023 at 10:24 UTC, following the strongest in the region of East Anatolian (Pazarcık) earthquake with Mw = 7.8 which occurred on the same day at 1:17 UTC to the south of the region. The Elbistan earthquake activated adjacent segments of the Chardak and Uluova faults with left-lateral strike-slip displacements. The resulting seismic ruptures have a total length of 190 km, of which 148 km are represented by sinistral lateral slip. Their maximum amplitude of 7.84 m was recorded 8 km east of the epicenter. The strike-slip seismic ruptures of the Elbistan and East Anatolian earthquakes represent exposure of their focal zones on the land surface. Both earthquakes exceed average values of these parameters for continental earthquakes of strike-slip type in terms of focal zone sizes and amplitudes of seismic displacements. At the same time, both sources do not propagate deeper than the upper part of the crust (16–20 km). Ophiolite assemblages covering the same depths are widely spread in the area of focal zones of both earthquakes. Two maxima were found in the distribution of seismic strike-slip displacement along the epicentral zone of the Elbistan earthquake (i) amplitudes of 5.7–7.84 m in the Chardak fault zone and (ii) amplitudes of 3.5–5.1 m in the Uluova fault zone. Both maxima coincide with the areas of ophiolites or their contacts with basement rocks. In crystalline basement rocks, the sinistral strike-slip amplitudes are significantly reduced. We attribute the increased values of focal zone sizes and displacement amplitudes of both earthquakes to the rheological features of ophiolites, which increase a possibility rocks slipping during seismic movements. We explain the fact that the sources of both earthquakes cover only the upper part of the crust by the uplift of the top of rocks with reduced P-wave velocities, including the upper mantle and the lower part of the crust, and interpret them as heated rocks with reduced strength. [ABSTRACT FROM AUTHOR]

A well-known and essential task in magnetic data interpretation is the structural mapping of basement terranes. Useful tools for analyzing the deep basement are edge-detection filters that normalize the first-/second-order gradients of the magnetic field in three spatial directions. Different edge-detection filters can reveal different structures; for example, filters that normally involve higher-order gradients may detect small-scale magnetic sources. This study aims to define magnetic bodies and interpret intra-basement structures from aeromagnetic data. For this purpose, we utilize three commonly used edge-detection filters that show edges as peaks, which can sometimes be quite broad. In addition, we suggest a new high-resolution filter that shows edges as a sharp crossover. The filters have been tested on the Bishop magnetic model and real airborne magnetic data from the Iraq Southern Desert (SD). Comparing the products of the proposed crossover filter with the three common filters shows similar high-resolution products, but the new filter can often highlight both shallow and deep subtle basement fabric. Our study of the SD magnetic dataset defined older reactivated regions, structural elements, and the trends of intra-basement fractures associated with more recent seismic events. [ABSTRACT FROM AUTHOR]

For a precise analysis of buildings under earthquake effects, the load–deformation behaviour of the bracing walls must be comprehensively known. The horizontal bracing walls are often clamped in the basement; however, less attention has been paid to these walls' clamping parts in the past. This study presents three shear wall experiments (NW 1, NW 2, NW 3) with heights up to six meters in a scale of 1:1.5 to the real size. Measured were the force–displacement curve, the curvature distribution over the height, the crack pattern, and the crack opening and spacing. Twelve displacement transducers, an optical measurement system with eight cameras, and a manual crack measurement were utilised. Out of the measurements, the impact of the tension shift effect on the load–displacement curves could be quantified for the cantilever part of the walls. Additionally, it was found out that a sliding failure in the clamping part must be considered if the aspect ratio of H/L is equal to or less than one. [ABSTRACT FROM AUTHOR]

Аbstract: The basement of Arctic Alaska–Chukotka microcontinent (AAChM) is exposed in the Velitkenai granite–metamorphic dome of Chukotka. U–Th–Pb (SIMS) geochronological study of the orthogneisses of the basement, paragneisses after Paleozoic rocks, and leucogranites of the Velitkenai massif in the central and southwestern parts of this structure was carried out. The Neoproterozoic age of basement orthogneisses (Velitkenai complex) and the Albian age of granitoids of the last stage of the Velitkenai massif were confirmed. The latter coincides with the age of migmatization of orthogneisses. The youngest zircon populations from paragneisses within the Velitkenai complex are from the Cambrian and the Silurian; single zircon crystals contain inherited cores with ages of 1.7 and 1.9 Ga. The correlation of the Neoproterozoic orthogneisses of the Velitkenai granite–metamorphic dome with similar complexes of the other AAChM regions indicates the unity of its basement. It is suggested to enter the Velitkenai metamorphic complex into the legend of the Chukotka series of the third-generation geological map sheets. [ABSTRACT FROM AUTHOR]

Schlumberger configuration of Vertical Electrical Sounding (VES) was deplored for groundwater exploration in Ugboshi-Afe study location. A total of nine (9) vertical electrical sounding (VES) locations, spread across the community were occupied to gain insights on the hydrogeological settings within the area. Quantitative computer interpretation of the data yielded three to six geoelectrical layers. The geoelectrical interpretation models were geologically interpreted as: clayey sand/sandy topsoil with resistivity values ranging from 54 Ohm-m to 424 Ohm-m, this is underlain by a relatively high resistivity layer (228-868 Ohm-m) interpreted as lateritic sand, and below this the low resistivity (21.38 Ohm-m - 42.4 Ohm-m) interpreted as clay, then the fractured/weathered geoelectric layer (95Ohm-m to 385Ohm-m), while the fresh basement has resistivity greater than 400 Ohm-m. Several maps such as fractured window thickness map, isoresistivity map of the fractured interval, overburden map were generated to investigate trends that may hold prospects for groundwater exploitation. Furthermore, hydroresistivity parameters such as Total Transverse Resistance, Total Longitudinal Conductance, Resistivity Reflection Co-efficient and Resistivity Contrast values were calculated for further screening of the study site for groundwater development. The VES1, VES2, VES6 and VES7 locations were concluded as holding prospects for groundwater potentials in the study area. [ABSTRACT FROM AUTHOR]

Introduction: Sediment bypass tunnels (SBTs) are operated during floods to reestablish sediment continuity past dams with the ultimate goal of decreasing accumulation in reservoirs. Depending on the location of the intake structure and operational conditions, SBTs may release either bed load-laden or bed load-free flows in the form of sudden floods (pulses). When evaluating the impacts of SBTs, the traditional approach has been to monitor channel changes in the years following project completion. However, by the time these impacts become evident, mitigation is challenging. Methods: This research adopts a forward-thinking methodology, emphasizing the prediction of potential impacts during the project's early planning stages. We use a one-dimensional morphodynamic model to forecast the potential morphological response of a gravel-bed river with an idealized geometry to a series of SBT operations characteristic of projects in the Swiss Alps. Results: The morphological response of the downstream reach over the medium to long term is influenced by the alternating pattern of bed load-laden and bed load-free flow releases. This pattern is instrumental in forming a transition region near the SBT outlet hydrograph boundary layer (HBL). Discussion: Within the (HBL), fluctuations in bed elevation and slope are localized, while variations in grain-size distribution persist throughout the downstream region. [ABSTRACT FROM AUTHOR]

The underground basement of a building is highly affected by anomalous seepage problems. Detection of seepage-prone regions through and around buildings becomes a need in other to sustain their stability. It is of great importance as well to have targeted remedies. However, traditional methods for examining these areas are often destructive and expensive, compelling the use of non-destructive geophysical techniques. This work aims to utilize and demonstrate the hands-on application of ground penetrating radar (GPR) and self-potential (SP) methods as an innovative combination to study seepage-prone zones in the basement of a building. Simulated responses of various seepage zones have been generated based on several significant factors. For better visualization, all 2D radargrams of a block were combined to produce a 3D model using GPR Slice software to distinguish various features at different depths. Higher positive SP values show the presence of high moisture or seepage-prone regions. Conclusively, the combined geophysical method of GPR and SP is trustworthy for conducting a quick and effective inspection of seepage-prone regions and probable source points for detailed characterization of the basement of a building. [ABSTRACT FROM AUTHOR]

The research considered in the paper was aimed at studying the structure and evolution of the Eastern Arctic structural–geodynamic systems. The tectonic model of the base of the Eastern Arctic plate section determines their vertical zonality in terms of structure and tectonics based on the interpretation of seismic and other geophysical survey data correlated at a varying reliability degree with the studied sections in the adjacent or remote areas. Accordingly, the vertical structure and formation composition models built on this basis are largely hypothetical and tend to change (even fundamentally) as geological and geophysical information accumulates. The geodynamic analysis of formation of the Eastern Arctic structural–geodynamic systems was based on tectonic–geodynamic paleoreconstructions recorded the interaction between blocks of the consolidated crust. The results we obtained made it possible to considerably update, expand and, in some cases, refine understanding of a structure of the basement and individual reference horizons of the sedimentary cover in this part of the water area. It is concluded that the East Arctic waters are of great interest in terms of hydrocarbon exploration. However, the assessment of their hydrocarbon potential is difficult due to the poor geophysical knowledge and lack of wells. [ABSTRACT FROM AUTHOR]

Objective: Iranian architecture has historically confronted various climatic challenges in desert regions, often leading to innovative solutions. One such challenge is the increase in temperature coupled with decreased relative humidity, particularly during the hottest days of the year. A sustainable climatic solution for achieving thermal comfort and mitigating harsh weather conditions in this region involves the integration of central courtyards and basements. However, the lack of moisture in the air renders the mere construction of these spaces insufficient for thermal comfort. To address this, pond spaces were incorporated into the yard and, in some cases, into the cellar or basement to help lower temperature and increase relative humidity. Method: This study employs descriptive and analytical methods alongside library and internet research. Additionally, simulation techniques were utilized to explore the impact of the pond factor within the two spaces of the cellar and yard. Results: The findings indicate that introducing a moisture source (pond) results in an average temperature reduction of up to 3.5 degrees Celsius in the yard and up to 2.5 degrees Celsius in the basement compared to scenarios without a pond on the hottest day of the year. Furthermore, the presence of a pond in the yard does not lead to significant changes in the temperature and humidity levels of the basement, even with air circulation. Conclusions: While the pond is essential for reducing the temperature of the yard itself and cannot be omitted from the design of desert homes, its role in enhancing thermal comfort within the cellar is particularly notable during peak heat hours. In the pond scenario, the temperature difference compared to the outside reaches approximately 9 degrees Celsius, whereas the scenario without the pond yields a difference of about 5 degrees. This underscores the undeniable importance of the water pond and the associated humidity in achieving thermal comfort. [ABSTRACT FROM AUTHOR]

The presented work deals with the numerical modeling of intense bedload-transport processes at confluences of mountain rivers and steep tributaries. Steep tributaries are characterized by having high transport capacities which supply large amounts of sediments to the confluence zone, where due to the sudden change in slope and the local hydraulic conditions, intense deposition can occur. The objectives of this study are to understand the potential applications and limitations of 2D numerical simulations for modeling these processes. The calibration of the applied 2D numerical model (BASEMENT, Basic Simulation Environment, v2.8) is based on comparing high-density point clouds of the confluence morphology at the end of flume experimental runs with numerical results. The calibrated numerical model is then used to test different discharge ratios and to investigate depositional patterns and mechanisms. The results show that key morphological features such as the confluence fan, the bank-attached bar and the scour hole can be accurately reproduced, showing that 2D numerical simulations are a valuable tool for modeling the complex interactions between morphodynamics and hydraulics at river confluences. Additionally, it is shown that the confluence morphology of steep tributaries and mountain rivers is strongly influenced by the sediment concentration in the tributary channel and the discharge in the main channel. [ABSTRACT FROM AUTHOR]

The physical and engineering properties of some basement rocks from parts of Oban Massif, Southeastern Nigeria were investigated to ascertain their suitability for civil engineering construction purposes. A total of 19 representative rock samples comprising of granites and granodiorites, were obtained from three quarries in Akamkpa Local Government Area of Cross River State, southeastern part of Nigeria. The rock samples were crushed into aggregates and their physical and mechanical properties were assessed. The results obtained showed that the specific gravity ranged from 2.60-2.72, water absorption 0.30-0.96%, aggregate impact value 12-30%, aggregate crushing value, 12-33%, flakiness and elongation Indices both ranged from 14-29%, the uniaxial compressive strength fell between 190 and 209NM/m,2 and the Los Angeles abrasion gave 14-41%. Petrographic studies suggested the rocks are granites and granodiorites. Results obtained from the research were compared with known engineering specifications. Such comparisons showed empirical relationships between the physical and the mechanical characteristics of the materials tested. These empirical relationships can, thus, be employed to save cost in future site investigations. Petrographic studies and engineering properties indicate that aggregates derived from the fresh basement rocks in the study areas are capable of withstanding heavy traffic, foundation loads and are generally suitable for most civil engineering construction purposes. It is also expected that the interpretation and ranking of the test results will provide a suitable guide to prospective clients of quarry operators as they can now have some scientific basis for selecting materials needed for different construction works. To achieve this, quarry operators must test and advertise/publicize the properties of their products for public consumption. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Athar alrafedain is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Large structural elements have been commonly observed in increasingly tall buildings, employing mass concrete elements in their foundations. In these elements, the internal heat generated by the cement hydration can be decisive for the occurrence of pathological manifestations arising from the balance of stresses and also by delayed ettringite formation. This article presents a practical and expedited method, through diagrams, for a preliminary assessment of the thermo-tensional risk involved in the concreting of large-scale elements. For the development of thermal risk diagrams, the commercial software TSA-2D was used, where 64 numerical computational simulations were conducted, varying the parameters with the greatest influence on the concrete thermal phenomenon (minimum dimension of the structural element, cement content per cubic meter, cement hydration heat, concrete placement temperature, and ambient temperature). The result of this methodology, when compared to computational simulations and field monitoring in a specific case study, showed a good correlation, with the potential for application and reproducibility, considering the natural limitations of an expeditious practice that needs to be evaluated on a case-by-case basis, but which provide an important guideline in the early decision-making on-site. Furthermore, the maximum absolute error between the results of computational simulation and field monitoring was only 1.6%.

Schlumberger configuration of Vertical Electrical Sounding (VES) was deplored for groundwater exploration in Ugboshi-Afe study location. A total of nine (9) vertical electrical sounding (VES) locations, spread across the community were occupied to gain insights on the hydrogeological settings within the area. Quantitative computer interpretation of the data yielded three to six geoelectrical layers. The geoelectrical interpretation models were geologically interpreted as: clayey sand/sandy topsoil with resistivity values ranging from 54 Ohm-m to 424 Ohm-m, this is underlain by a relatively high resistivity layer (228-868 Ohm-m) interpreted as lateritic sand, and below this the low resistivity (21.38 Ohm-m – 42.4 Ohm-m) interpreted as clay, then the fractured/weathered geoelectric layer (95Ohm-m to 385Ohm-m), while the fresh basement has resistivity greater than 400 Ohm-m. Several maps such as fractured window thickness map, isoresistivity map of the fractured interval, overburden map were generated to investigate trends that may hold prospects for groundwater exploitation. Furthermore, hydro-resistivity parameters such as Total Transverse Resistance, Total Longitudinal Conductance, Resistivity Reflection Co-efficient and Resistivity Contrast values were calculated for further screening of the study site for groundwater development. The VES1, VES2, VES6 and VES7 locations were concluded as holding prospects for groundwater potentials in the study area.

Introduction: Sediment bypass tunnels (SBTs) are operated during floods to re-establish sediment continuity past dams with the ultimate goal of decreasing accumulation in reservoirs. Depending on the location of the intake structure and operational conditions, SBTs may release either bed load-laden or bed load-free flows in the form of sudden floods (pulses). When evaluating the impacts of SBTs, the traditional approach has been to monitor channel changes in the years following project completion. However, by the time these impacts become evident, mitigation is challenging.Methods: This research adopts a forward-thinking methodology, emphasizing the prediction of potential impacts during the project’s early planning stages. We use a one-dimensional morphodynamic model to forecast the potential morphological response of a gravel-bed river with an idealized geometry to a series of SBT operations characteristic of projects in the Swiss Alps.Results: The morphological response of the downstream reach over the medium to long term is influenced by the alternating pattern of bed load-laden and bed load-free flow releases. This pattern is instrumental in forming a transition region near the SBT outlet hydrograph boundary layer (HBL).Discussion: Within the (HBL), fluctuations in bed elevation and slope are localized, while variations in grain-size distribution persist throughout the downstream region.

Electrical resistivity techniques of geophysical prospecting have been used to evaluate the groundwater potential of the University of Abuja Health Services Centre at the main campus. This research aims to identify suitable locations for productive wells and boreholes, determine the depth of the bedrock, as well as measure resistivity and overburden thickness. The survey employed Vertical Electrical Sounding (VES) along five profiles, comprising fifty (50) VES stations covering the survey area. The resistivity data obtained are analysed using IPI2win software. The analysis of the resistivity data revealed that the survey area can be divided into four geoelectric layers: topsoil, clayey sand, weathered layer, and fresh basement. The resistivity values of these layers range from 38.7-1427 Ωm, 16.2-310 Ωm, 32.1-1714 Ωm and 1007-9528 Ωm respectively. The fresh basement layer was found to have an infinite thickness. Significantly, potential regions with low resistivity values indicating the presence of groundwater were identified at a depth of 18.3 m. Furthermore, the average overburden thickness in the study area was 35 m while the longitudinal conductance of the overburden ranges from 0.04 – 1.87 mho. Results obtained indicate the main aquifer in the area consists of a thick weathered layer of overburden and a weathered basement with relatively low resistivity, suggesting a potentially productive groundwater yield. This information is crucial for future planning and decision-making regarding the siting of wells and boreholes and the sustainable utilisation of groundwater resources in the University of Abuja main campus.

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to ascertain the governing mechanisms, sources, and speciation of ionic species, identify hydrochemical facies, and assess their appropriateness for agricultural use, groundwaters from several portions of the semi-arid basement complex of north–central Nigeria were analyzed based on chemistry. Basement aquifers made of gneiss-migmatites, metasediments, and granitoids store groundwater. Standard analytical techniques were used to analyze the fluids for main cations, anions, and physical characteristics. The results showed that the waters were slightly acidic (with a mean pH of 5.38, below the permissible range of 6.5–8.5), and that the predominant cations and anions were Na+ >Ca2+ >K+ >Mg2+ and Cl− > NO3- > HCO3- > SO42−, respectively. Analysis of the ions' stoichiometric ratios reveals that alkali elements predominate, making up about 55.3% of the ions and being connected to silicate weathering. Based on ionic ratio calculations, it was determined that ion exchange was a key factor controlling water chemistry. Ionic species cross plots show that silicate weathering (sodic and calcic plagioclase) predominates. Hydrochemical facies, Gibbs plots, and principal component (correlation, cluster and factor) studies all show that ionic elements are geogenic, essentially coming from the weathering of silicates with ion exchanges. Based on predicted saturation indices, hydrochemical modeling by the computer program VISUAL-MINTEQ reveals that the majority of main ions occur in free mobile states with associated mineral species, all at undersaturated levels. Based on measurements of the sodium adsorption ratio (SAR), sodium percentage (% Na), and chloro-alkaline indices (CAI), the waters have been evaluated for their suitability for agricultural use.

Digital models of the deep structure of the Earth's crust are developed based on the method of gravity modeling, taking the accumulated geophysical data on the Eurasian Basin of the Arctic Ocean into account. The digital models of the basement relief and sedimentary cover thickness in the Eurasian Basin are calculated on the basis of reinterpretation of depth multi-channel reflection seismic cross-sections and 2D gravity modeling. The digital models of the Moho surface relief and the thickness of the Earth's crust are calculated using the improved 3D gravity modeling method. It is shown that the reason for the deepening of the basement in the Nansen Basin by 1–1.5 km in comparison with the Amundsen Basin is a larger volume of accumulated sedimentary cover in the Nansen Basin, with a similar crustal thickness of ~4.8 km in both basins. The characteristics of the oceanic crust studied on the basis of the obtained digital models reveal a complex 3D variability typical of ultraslow spreading ridges. In the region of the Gakkel Ridge, which was formed at full rates of spreading of less than 12 mm/year, the maximum spread of crustal thicknesses occurs and the tectonic factor dominates over the magmatic one during the accretion of the oceanic crust. This manifests itself in the formation of extended submarine ridges parallel to the amagmatic segments of the ridge. [ABSTRACT FROM AUTHOR]

The paper presents the results of a geological interpretation using gravity, magnetic, and seismic data to understand the oil and gas potential of pre-Jurassic sedimentary intervals and basement in the central West Siberia basin. The 200 km long Pai-Khoi-Altai strike-slip zone was investigated. Reconstruction based on a data complex indicate the right-lateral kinematics of the principal strike-slip faults and possible fault inversion. The study evaluated the spatial and genetic relationship between the conditions for hydrocarbon trap development and the strike-slip fault systems, such as "flower structures". Strike-slip geometry and kinematics are confirmed based on 2D and 3D seismic data. Geological and geophysical criteria are used to forecast localization of hydrocarbon fields. Predictive zones are elongated in several different directions and have a different distribution pattern in the blocks separated by principal strike-slip faults, confirming its significance as a controlling factor for the hydrocarbon potential of the region's structures. [ABSTRACT FROM AUTHOR]

The study area is composed of mainly basement rocks, with problems of low yield of groundwater in most of the boreholes drilled. Therefore, this study was carried out to evaluate the hydraulic parameters of the basement aquifers using the vertical electrical sounding (VES), constant rate pumping test, and borehole logs. The mean value of aquifer resistivity and thickness are 408.4 Ωm and 20.2 m. The depth ranges from 20.9-88.0 m with a mean value of 55.5 m; showing appreciable groundwater potential mostly within the southern part. The value of transmissivity and hydraulic conductivity from the resistivity data ranges from 2.058-1761.033 m2/day and 0.205-138.664 m/day with a mean value of 152.251 m2/day and 8.841 m/day, respectively, indicating porous and permeable zones within the southern and northwestern part of the study area. The value of longitudinal conductance and transverse unit resistance ranges from 0.0034-4.2333 m-hom and 38.1-146439 Ωm2 with a mean value of 0.3250 m-hom and 9704.1 Ωm2; indicating poor to moderate protective capacity in almost the entire area except for the small portion within the southern part. The mean value of fracture contrast and the reflection coefficient are 0.743 and -0.333, showing that the southern part has more water-filled fractures. Conclusively, this study reveals, that the aquifer depth ranges from 60-90 m, the transmissivity and hydraulic conductivity demonstrate high porosity and permeability within the southern parts of the study area, and serve as a baseline for groundwater resource management policy in Nigeria.

In 1998, Hartgen Archeological Associates, Inc., excavated the remains of the John Bogart House basement in downtown Albany, New York. Archaeologists found a small artifact-filled barrel buried below the floor adjacent to an interior dividing wall. Most striking were the number of sharp and modified objects within this barrel and elsewhere under the basement floor that were likely hidden or lost by enslaved African Americans who occupied the space during the late 18th century. Albany underwent a dramatic social and political transformation at the end of the 18th century, causing anxiety and tension with the city. Within this uncertain post-Revolutionary climate, Albany's African American community expressed a measure of public autonomy through the Pinkster festival. At the same time, African Americans at the Bogart House were carefully curating multivalent objects to express personal autonomy and group identity in the face of often violent repression. [ABSTRACT FROM AUTHOR]

The Liskin fault zone located in the southeastern part of the East European Platform at the boundary between two large neotectonic structures, that is, the Voronezh Uplift and the Oka–Don basin, is considered. Earthquake epicenters are concentrated in the fault zone and the adjacent territory. The neotectonic structures of the territory, topography, structure of the multi-depth and age horizons of the sedimentary cover, basement, crust, Moho surface are investigated, and the causes of neotectonic and seismic activity of the zone are determined. At present, the Liskin fault develops as a thrust fault with a dextral strike-slip component under the conditions of submeridional compression and the adjacent territory is under the influence of multidirectional tectonic compression stresses: from the north, from the Oka–Don basin and from the south, from the Caucasian segment of the Alpine collision belt. This is reflected in the morphology and structure of the neotectonic structures. The deformation of multi-depth horizons as well as the Earth's surface and the activation of seismicity are associated with the submeridional compression. The deep material and structural inhomogeneities of the Earth's crust are of great importance. The collision zone between two oncoming submeridional stresses that led to active seismicity has been identified in the neotectonic structure of the south-eastern part of the East European Platform for the first time. [ABSTRACT FROM AUTHOR]

Copyright of Guangdong Architecture Civil Engineering is the property of Guangdong Architecture Civil Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The first results of laser ablation inductively-coupled plasma mass-spectrometry apatite fission-track dating are presented from drill core of boreholes, which exposed the top of the Siberian Platform's crystalline basement in the Nepa–Botuoba Anteclise. Apatite fission-track ages, obtained for nine samples from a depth of ~2 km, form three groups with mean values of 200, 140, and 60 Ma. A thermal event with an age of ~200 Ma is widely abundant almost within the entire Siberian Platform and reflects the stage of its intense Early Jurassic uplifting. Resetting of the apatite fission-track system ~140 Ma corresponds to tectono-thermal events, which mark the final stage of collision of the Mongol–Okhotsk fold belt. The youngest apatite fission-track ages age of ~60 Ma, on the one hand, may reflect the beginning of the Baikal rifting and, on the other hand, may be a result of the high U content of apatite. [ABSTRACT FROM AUTHOR]

Purpose. To study and assess the possibility of effective application of electrical prospecting by magnetotelluric sounding (MTsounding) and to determine the range of geological problems to be solved in the geoelectric conditions of the Shu-Sarysu geotraverse. Methodology. The issues of methodology of modern technologies of field observations, peculiarities of processing and interpretation of MT-sounding data are considered, which showed that modern instrumental and methodical electrical survey technologies of MT-sounding allow obtaining results of field measurements of increased reliability, due to their accuracy, productivity, mobility, noise immunity, level of automation. To identify the main features of the geoelectric structure of the Earth’s crust and the upper mantle, the modern technique of interpreting MT data allows for 1, 2D inversion of the effective curves of apparent resistivity and impedance phase. Findings. Based on MT-sounding data, a geoelectric section of the Shu-Sarysu geotraverse was constructed, characterizing the position and morphology of five geoelectric boundaries in the crustal section in the 0–40 km depth interval. The identified five geoelectric horizons show good coincidence with the conventional seismic horizons and confidently correlate with the geological references established by GIS data. Originality. On the basis of MT-sounding studies, the geological interpretation of the structure of suprasalt and subsalt structural- formation complexes is presented; the geological efficiency of MT-sounding electrical prospecting in revealing the complex structures in the conditions of the Shu-Sarysu geotraverse is shown. On the basis of model constructions of the geoelectric section, new data on the deep geological structure of the Shu-Sarysu geotraverse were obtained: new data on the structure of Mesozoic terrigenous-sedimentary rock complexes and the Paleozoic part of the section with the allocation of the supposed faults; on the basis of MT-sounding results, recommendations for further detailed geological exploration work were given. Practical value. A comprehensive interpretation is recommended of the obtained MT-sounding data together with the results of geological and geophysical research on the regional profile in order to establish search criteria for the discovery of mineral deposits and the prospects of gas content in the area. [ABSTRACT FROM AUTHOR]

The Noahic Flood deposited and emplaced a significant amount of sedimentary and volcanic rock on the continents. Much of it remains despite appreciable Recessional Stage erosion. How much? We answer using a method in Colorado as a pilot for many other locations. The principle is simple: creating grids of the basal and upper diluvial boundaries, then subtracting the lower from the upper. In Colorado, we chose the top of the Precambrian crystalline surface as our basal boundary and digitized a Colorado Geological Survey map into a Geographic Information System (GIS). NOAA's ETOPO1 Digital Elevation Model (DEM) of surface topography was selected as the upper boundary. Small volumes of Precambrian sedimentary and metasedimentary rocks and most of the San Juan and Thirty-Nine Mile volcanic fields were not included in the final calculation, and minor postdiluvial sediments were ignored. The total Flood rock record in Colorado totals more than one-half million cubic kilometers, predominantly in six sedimentary basins. Our method allows recalculation for revised or alternate boundaries. [ABSTRACT FROM AUTHOR]

The impact of Geology on groundwater is not fully appreciated in many Nigerian groundwater quality literature. This study investigates the influence of Geology on the hydrogeochemical makeup of groundwater in Igarra and environs, Nigeria. Igarra and environs is underlain by metasediments intruded by Pan African Granites. Ten water samples were collected and analyzed in the laboratory to determine their chemical composition. The results revealed that the pH of most samples was slightly acidic to mainly alkaline, with high electrical conductivity (EC) and total dissolved solids (TDS) values. Correlation and regression analyses showed that the TDS, EC, salinity, chemical oxygen demand, dissolved oxygen, and major and minor constituents positively influenced the pH of the groundwater. Hierarchical cluster analysis demonstrated that the water samples had different compositions and concentrations based on local geological influences. The water samples from Granite, Quartzites, Migmatites and Gneiss rock types shared similar characteristics and had a lower concentration of minerals than the water samples taken from the Quartz Mica Schists and Metaconglomerates. The water in Igarra was predominantly Magnesium Bicarbonate type. However, some of the water samples exceeded the drinking standards for TDS, EC, Cl, Fe, Cr, Cd, and Pb. The study recommends the inclusion of biological parameters to gain a clearer picture of the water quality, particularly from the anthropogenic point of view. [ABSTRACT FROM AUTHOR]

The impact of Geology on groundwater is not fully appreciated in many Nigerian groundwater quality literature. This study investigates the influence of Geology on the hydrogeochemical makeup of groundwater in Igarra and environs, Nigeria. Igarra and environs is underlain by metasediments intruded by Pan African Granites. Ten water samples were collected and analyzed in the laboratory to determine their chemical composition. The results revealed that the pH of most samples was slightly acidic to mainly alkaline, with high electrical conductivity (EC) and total dissolved solids (TDS) values. Correlation and regression analyses showed that the TDS, EC, salinity, chemical oxygen demand, dissolved oxygen, and major and minor constituents positively influenced the pH of the groundwater. Hierarchical cluster analysis demonstrated that the water samples had different compositions and concentrations based on local geological influences. The water samples from Granite, Quartzites, Migmatites and Gneiss rock types shared similar characteristics and had a lower concentration of minerals than the water samples taken from the Quartz Mica Schists and Metaconglomerates. The water in Igarra was predominantly Magnesium Bicarbonate type. However, some of the water samples exceeded the drinking standards for TDS, EC, Cl, Fe, Cr, Cd, and Pb. The study recommends the inclusion of biological parameters to gain a clearer picture of the water quality, particularly from the anthropogenic point of view.

West Papua province in eastern Indonesia is positioned in a dynamic tectonic zone along with the collision of the Australian, Pacific, and Eurasian plates. The interaction resulted in the formation of strike-slip faults such as Koor, Sorong, Ransiki, and Yapen, that are prone to earthquakes in the region. The rocks of West Papua in the northern part are a contribution to the Pacific Ocean plate consisting of ophiolite and volcanic arcs of the archipelago, even while the rocks of the Australian plate in the southern part are dominated by quaternary and siliciclastic sedimentary. It has a wide variety of resources, including oil and gas. This study combines the interpretation of regional gravity and magnetic data derived from satellite observations to identify the subsurface structure of West Papua. This is performed since most studies were conducted on the surface and did not significantly focus on the subsurface. The composition of subsurface is determined through three-dimensional (3-D) unconstrained inversion modeling using the iterative reweighting inversion of regional gravity and magnetic anomalies as a function of density contrast and magnetic susceptibility of rocks. In depth variations, gravity inversion produces density contrast ranging from − 0.348 to 0.451 gr/cm3, whereas magnetic inversion provides rock susceptibility varying between − 0.363 and 0.223 SI. Gravity and magnetic inversions characterize the subduction of the Pacific Ocean plate in the north, extensive intrusion of igneous rocks, and low density-susceptibility contrast in the Bintuni basin as a source of oil and natural gas. The boundary between the sediment layer and the basement is believed to be 15–20 km deep, with rocks from the uplifted mantle in the north and a Silur-Devon aged Kemum formation in the south. [ABSTRACT FROM AUTHOR]

Copyright of Jurnal Greenation Ilmu Teknik (JGIT) is the property of Greenation Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

High-resolution airborne magnetic data over Auchi and its environ, have been analysed with a view to delineate the geological lineaments, estimate source parameters within the studied area. The geological lineaments were mapped using horizontal gradient magnitude and analytical amplitude signal method. The total magnetic intensity (TMI) values of Auchi and its environs ranges between - 68.52885 nT and 79.85480 nT with clear disposition of different geological zone and distinct anomaly ranges. TMI map reflects the variations in the magnetic field intensity and amplitude, indicating variations in lithology and Basement morphology across the study area. The Centre for exploration targeting porphyry analysis revealed and identifies linear geological structures within the study area contained within the high resolution airborne magnetic data through standard deviation. The output estimates magnetic variations and thereafter, filtered using phase symmetry to separate laterally continuous lines. The resulted lineaments was enhanced (Signal to noise ratio) by suppressing noise and background signals using an amplitude thresholding operator which produced vectorization map. The vectorization analysis revealed the Basement rocks which occupy both the eastern and western parts of the study area covered by cretaceous sandstone. [ABSTRACT FROM AUTHOR]

A detailed geophysical investigation was carried out to determine if the subsurface geology is responsible for the failures along this road section. This study aims to image and identify competent, moderately competent, and incompetent zones of the subsurface soil and thus to find out if geology is responsible for the failure along this section of the road. Electrical Resistivity Imaging (ERI) using the Wenner array 2D Imaging, and Vertical Electrical Sounding (VES) using the Schlumberger array were adopted for this survey. The geoelectric section from the VES revealed the presence of 3 lithological layers; topsoil, weathered layer (clay, sandy clay, clayey sand), and basement, which is also true for the electrical resistivity images revealed by the 2D electrical resistivity imaging. The results showed that the shallow subsurface beneath the road section is mostly underlain with clay that is geotechnically incompetent and not suitable for construction. The causes of road failure are believed to be the result of the incompetent clayey topsoil and the weathered layer seen in the profiles, which expand when absorbing water and shrink when drying, thus causing instability beneath the pavement due to the low shear strength and high compressibility, and also due to fractured basement rocks at shallow depths. [ABSTRACT FROM AUTHOR]