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Abstract Commercial scale decarbonization through carbon capture and storage may likely involve many CO2 storage projects located in close proximity. The close proximity could raise concerns over caprock integrity associated with reservoir pressure buildup and interference among adjacent projects. Commercial-scale injection will also require large prospective CO2 storage resource and high injectivity in the targeted storage formations. To accommodate the need for both large resource and high injectivity, project operators could consider injecting CO2 into a stacked sequence of formations. This analysis investigates the benefits of injecting CO2 into a vertically stacked sequence of saline formations, over injecting the same amount of CO2 into a single saline formation, in addressing these challenges. Our analysis shows that injecting into the stacked sequence mitigates the extent of pressure buildup among the stacked formations, while still achieving the same or greater target CO2 storage volumes. Among cases modeled, the resulting pressure buildup front is most reduced when each storage site distributes injection volumes over several wells, each of which injects a portion of the total CO2 mass across the stacked sequence. This favorable case not only results in the smallest CO2 aerial footprint, but also shows the largest reduction in the pressure buildup at the top of perforation at the injection wells (upwards of approximately 46% compared to the single-formation storage), the result of which is crucial to maintain caprock integrity. This analysis provides insights into required decision-making when considering multi-project deployment in a shared basin.

Commercial scale decarbonization through carbon capture and storage may likely involve many CO2 storage projects located in close proximity. The close proximity could raise concerns over caprock integrity associated with reservoir pressure buildup and interference among adjacent projects. Commercial-scale injection will also require large prospective CO2 storage resource and high injectivity in the targeted storage formations. To accommodate the need for both large resource and high injectivity, project operators could consider injecting CO2 into a stacked sequence of formations. This analysis investigates the benefits of injecting CO2 into a vertically stacked sequence of saline formations, over injecting the same amount of CO2 into a single saline formation, in addressing these challenges. Our analysis shows that injecting into the stacked sequence mitigates the extent of pressure buildup among the stacked formations, while still achieving the same or greater target CO2 storage volumes. Among cases modeled, the resulting pressure buildup front is most reduced when each storage site distributes injection volumes over several wells, each of which injects a portion of the total CO2 mass across the stacked sequence. This favorable case not only results in the smallest CO2 aerial footprint, but also shows the largest reduction in the pressure buildup at the top of perforation at the injection wells (upwards of approximately 46% compared to the single-formation storage), the result of which is crucial to maintain caprock integrity. This analysis provides insights into required decision-making when considering multi-project deployment in a shared basin. [ABSTRACT FROM AUTHOR]

Abstract Investigating the mineralogical compositions of soils under different geological formations becomes imperative for maximizing agricultural productivity and ensuring the long-term viability of agricultural practices. Therefore, studies were carried out on mineral compositions and diversities of soils developed over the Basement complex rock, Coastal plain sands and Ewekoro formations in Ogun state Nigeria. A total of nine profile pits (three per location) of 2 m × 1 m × 2 m size were dug in all the three locations. Soil samples were collected from the pedogenic horizons of each profile pits in replicates into a well labeled polyethylene bag. Using X-ray diffractometry (XRD) and scanning electron microscopy (SEM) the mineral contents and their relative abundance, elemental compositions and morphologies of the fine sand, coarse silt and clay fractions of the soils at different topographic positions were identified, described and compared. Results obtained from XRD and SEM analyses exhibited similarities. The most abundant elements in the basement complex and Ewekoro pedon were oxygen, carbon and silicon whereas in the coastal plain sand pedon, oxygen, carbon and aluminum were the most abundant element. The presence of mixed-layer illite, mica, kaolinite, quartz, hematite, anatase, goethite, and chlorite at varying degrees was observed in the pedons developed on these geological formations, although kaolinite and quartz dominated the soil matrix. The mineralogical complexity of the pedons followed the order of basement complex > coastal plain sand > Ewekoro formation. Profiles developed on the Ewekoro formation exhibited the highest degree of weathering, as evidenced by their chemical properties and mineralogical compositions. The petrographic evaluation of the three geological formations revealed that all pedons were rich in quartz and exhibited varying degrees of mineral complexity and maturation. The overlapping and distinct characteristics among the geologies indicated different stages of weathering. By using the mineral maturity index, profiles developed over the basement complex rock and the coastal plain sand could be regarded as sub-matured and this could have contributed significantly to the native fertility of these soils and profiles from the Ewekoro formation were the most weathered. The use of Ewekoro formation for agriculture would necessitate significant investments in agro-inputs and sound principles of soil management through integrated soil fertility management.

Terrestrial gamma radiation is the major source of outdoor radiation exposure to human being. Because of the variation of underlying geological characteristics of surface soil, the terrestrial gamma radiation dose (TGRD) rates vary significantly with the soil type. This work performed in situ measurements of the TGRD rate for a range of geological formation and soils of Katsina State, Nigeria by using a portable hand-held radiation survey metre, RADOS. The TGRD rates ranged between 45 and 271 nGyh−1 with an overall mean value of 116 nGyh−1, which is two times higher than the world average value of 59 nGyh−1. Geological formation (Silicified sheared rock) was found to have the highest mean TGRD value of 163 nGyh−1. Likewise, soil type (lithosols, ferruginous crusts and ferruginous tropical soils) appeared to have the highest mean TGRD value of 134 nGyh−1. One-way ANOVA was used to investigate the variation of the significant difference between the geological formations and soil types with TGRD, which shows the influence of geological formation and soil types on the measured TGRD values of the study area. Measured data could further be used to evaluate the public radiation exposure and in formulating safety standards and radiological guidelines. [ABSTRACT FROM AUTHOR]

This study assessed and compared selected soil properties, oil and grease content, and thermophysical parameters of sandy loam soils from two representative automobile mechanic village (MV) on two different geological formations in Ogun State, Nigeria. The two locations: Abeokuta and Sagamu are situated on a basement complex and Cretaceous-sedimentary formations, respectively. Ten sample points were established on each MV. Physico-chemical and in-situ thermal properties were measured using standard methods and KD2 Pro thermal analyzer, respectively. Three different regression models (linear, semi-log and double-log) were generated for the prediction of thermal conductivity ([Formula: see text]) and specific heat capacity ([Formula: see text]). Topsoils in both MVs are slightly acidic to neutral, with an average oil and grease content > 100 mg/kg. Results of thermophysical parameters revealed that the average [Formula: see text] values in MV soils of basement complex and sedimentary backgrounds were 1.656 and 1.988 W/mK, respectively. The average [Formula: see text] values in Abeokuta and Sagamu MV soils are 2.295 and 3.043 MJ/m3K, respectively. The regression analysis showed that the double log model performed better than both linear and semi log models for predicting [Formula: see text] at both locations. All the tested regression models have good prediction effects on [Formula: see text] at location within cretaceous sedimentary, whereas linear and double-log models proved feasible for predicting [Formula: see text] at location underlain by basement complex.

The Middle Miocene of the Despotovac area contains sediments of the lower Middle Miocene (Badenian) and upper Middle Miocene (Sarmatian). The Middle Miocene deposition shows different local variations, but generally fits the evolution of the Central Paratethys. The Miocene sediments were analyzed using paleontological and sedimentological methods. Based on the results of these investigations, the Golubac Formation (Badenian) and the Kamenovo Formation (Sarmatian), which had previously been defined and documented on the Kučevo sheet, were recognized for the first time within the sediments of the Middle Miocene study area on the sheet Lapovo 4.

The south eastern region of Pacitan Regency, East Java, Indonesia, is directly facing opposite the direction of the Indo-Australian plate movement, and has a diverse geological structure with different rocks occurring on land surface. This research aims to determine the infl uence of geological formations on soil characteristics and quality and the limiting factors of soil quality. Soil samples were taken from 40 sampling points from 10 geological formations from the topsoil (tillage layer) at a 0-30 cm depth. The number of sample points is adjusted to the area of the geological formation, where the wider the geological formation, the more samples are taken. Soil characteristics data were analysed using Anova test and Duncan test to get information on the infl uence of geological formations on soil characteristics. Pearson correlation test and principal component analysis (PCA) were used to calculate the soil quality index, and the Kruskal-Wallis test to analyse the infl uence of geological formations on soil quality. The result shows that the soil mineral composition is mostly inherited from andesitic-basaltic parent rocks which has experienced weathering. Geological formation has an infl uence on bulk density, soil water content, porosity, cation exchange capacity and soil organic carbon content. The soil quality index value for various geological formations is in the range of 0.31-0.39, so it is included in the low to medium class. Jaten Formation and the Watupatok Formation do not have limiting factor on soil quality, base saturation (BS) is a limiting factor in Oyo Formation, and soil organic carbon (SOC) and total nitrogen (TN) are limiting factors in almost all geological formations..In conclusion, geological formations signifi cantly infl uence several soil characteristic parameters but are not the dominant factor determining soil quality. [ABSTRACT FROM AUTHOR]

In an attempt to better explore organic matter reaction and properties, at depth, to oxidative fluid additives, we have developed a new ReaxFF potential to model and describe the oxidative decompositions of aliphatic and aromatic hydrocarbons in the presence of the oxychlorine ClO n - oxidizers. By carefully adjusting the new H/C/O/Cl parameters, we show that the potential energies in both training and validation sets correlate well with calculated density functional theory (DFT) energies. Our parametrization yields a reliable empirical reactive force field with an RMS error of ∼1.57 eV, corresponding to a 1.70% average error. At this accuracy level, the reactive force field provides a reliable atomic-level picture of thermodynamically favorable reaction pathways governing oxidative degradation of H/C/O/Cl compounds. We demonstrate this capability by studying the structural degradation of small aromatic and aliphatic hydrocarbons in the presence of oxychlorine oxidizers in aqueous environments. We envision that such reactive force fields will be critical in understanding the oxidation processes of organic matter in geological reservoirs and the design of the next generation of reactive fluids for enhanced shale gas recovery and improved carbon dioxide adsorption and sequestration.

Hydrogen-based technologies are among the most promising solutions to fulfill the zero-emission scenario and ensure the energy independence of many countries. Hydrogen is considered a green energy carrier, which can be utilized in the energy, transport, and chemical sectors. However, efficient and safe large-scale hydrogen storage is still challenging. The most frequently used hydrogen storage solutions in industry, i.e., compression and liquefaction, are highly energy-consuming. Underground hydrogen storage is considered the most economical and safe option for large-scale utilization at various time scales. Among underground geological formations, salt caverns are the most promising for hydrogen storage, due to their suitable physicochemical and mechanical properties that ensure safe and efficient storage even at high pressures. In this paper, recent advances in underground storage with a particular emphasis on salt cavern utilization in Europe are presented. The initial experience in hydrogen storage in underground reservoirs was discussed, and the potential for worldwide commercialization of this technology was analyzed. In Poland, salt deposits from the north-west and central regions (e.g., Rogóźno, Damasławek, Łeba) are considered possible formations for hydrogen storage. The Gubin area is also promising, where 25 salt caverns with a total capacity of 1600 million Nm3 can be constructed. [ABSTRACT FROM AUTHOR]

The preparation of geological maps based on field data and the application of aerial photographs have always been an error because of the structural diversity of the earth and the difficulty of accessing certain regions. But in recent decades, the use of satellite imagery has but in recent decades, the use of satellite imagery has gone a long way to increasing the accuracy and timeliness of geological mapping. The purpose of the current study is to investigate the applicability of Landsat 8 satellite images and object-oriented pixel classification methods in mapping the geological formations of some part of the Shirkuh Mountain range in Yazd province. This area is part of the scattered mountain range of Central Iran with a dry climate and minimal vegetation. Initially, enhanced operations were performed to identify geological information’s using MNF, PCA and FCC processing. Then, the images were classified using object-oriented algorithms (BAYES, SVM, KNN, Decision Tree and Random Forest), neural network (ARTMAP, RBF, MLP and SOM), and base pixels (Maximum Likelihood, Minimum Distance, Mahalanobis and SAM). Next, the error rate of each method was calculated using Boolean logic and kappa coefficient. The results showed that the maximum probability classification with kappa coefficient of 75% in the base pixel category, Fuzzy ARTMAP classification in neural network method with kappa coefficient of 72% and Bayesian classification in object-oriented method with kappa coefficient of 82% have the best results among other methods. These results show that the methods mentioned in the identification and separation of geological formations are effective. The SAM of pixel-based methods, SOM of neural network methods and RF of object-oriented methods with 49%, 64% and 61%, respectively, showed the lowest accuracy in each category.

Our increased reliance on fossil fuels and its environmental effects have led us to prioritize transitioning to a carbon-free economy and using renewable sources of electric power. Hydrogen is an environmentally friendly, non-carbon-based energy source that can replace fossil fuels. It is critical to create a long-term storage medium to balance its intermittent supply and demand. Developing a full-scale H 2 economy requires large-scale H 2 storage. H 2 storage in geological formations is being explored as a possible option where it can be withdrawn again at a larger stage for utilization. This study examines global underground operational and prospective locations to provide a comprehensive overview of the current state of hydrogen storage worldwide. Underground geological formations have effectively stored H 2 , as shown in the literature review. Geochemical, microbiological, hydrodynamic, and geomechanic factors affected by injected hydrogen are some of the key challenges in storing hydrogen in deep geological formations. These factors have a significant impact on the project's performance and operating efficiency. A roadmap for the implementation of underground hydrogen storage (UHS) is presented. The economic aspects of UHS were analyzed. Research is still ongoing on the potential effects of storing hydrogen in salt caverns, depleted oil and gas reservoirs, and saline aquifers, subsurface geological media. This study also encompasses the state-of-the-art hydrodynamic, geo-chemical and geo-mechanical modeling studies in the UHS domain, as well as several modeling software tools. Finally, conclusions, recommendations and further investigations were provided. • Major kinds of underground hydrogen storage (UHS) are assessed. • UHS either pure or in the form of a gas mixture, is a promising approach. • UHS is not yet ready for complete industrial and nationwide integration. • Modeling techniques improve understanding of underground reservoir dynamics. • UHS in salt caverns is seen as technically mature. [ABSTRACT FROM AUTHOR]

This review focuses on the consequences of the early and rapid deployment of carbon dioxide (CO2) capture and storage (CCS) technologies, which is currently recognized as a critical problem in fulfilling climate change mitigation objectives and as a viable alternative for countries throughout the world. Currently, the geological storage of CO2 is the most effective and, in many cases, the only viable short- to medium-term alternative for considerably moving towards CO2 sequestration in geological sinks and, thus, lowering net carbon emissions into the atmosphere. Furthermore, this review explores the global and environmental measurements of CO2 emissions, as well as the emphasis behind more efficient energy usage. The components of the CCS system are briefly examined, with an emphasis on the technologies that have been developed by previous scholars to support carbon capture, as well as the kinds of carbon geological formations that are suitable sinks for CO2. Additionally, the importance of carbon interaction and sequestration in unconventional formations are examined through case studies that are applied to coalbed seams and shale gas reservoirs. Numerous trapping processes are grouped and introduced in a constructive matrix to easily distinguish the broad trapping mechanisms, which are (1) chemical, (2) physicochemical, and (3) physical trapping, and each of these categories are further classified in depth based on their contribution to CO2 storage. [ABSTRACT FROM AUTHOR]

Morphometric analysis reveals the development of land surface processes and provides an insight into hydrologic behaviour of watershed. A morphometric analysis of landforms on basalt, granite gneiss and schist in north Karnataka was conducted with the objective of comparing various morphometric parameters among them. A sub-watershed each was selected to represent landform on basalt, granite gneiss and schist. The stream length was highest in sub-watershed on basalt and was least on schist with one on granite gneiss being intermediate. The stream number was highest in basalt and its values were similar in granite gneiss and schist. Total relief, relief ratio and ruggedness number were distinctly high in sub-watershed on schist compared to the other two. The low mean bifurcation ratios in all three sub-watersheds suggested stability of the landforms. Drainage density was relatively coarser in the sub-watershed on granite-gneiss compared to the other two. The drainage network was dendritic in the sub-watershed on basalt, sub-dendritic on granite gneiss and sub-trelis on schist. The drainage texture and texture ratio were slightly higher, overland flow values were lower in sub-watersheds on basalt and schist compared to that on granite-gneiss. All three sub-watersheds exhibited similar elongation ratio, form factor and circularity ratio.

The wave frequency and energy of traditional piezoelectric emission sources used in acoustic logging are limited, which results in an inadequate detection resolution for measuring small-scale geological formations. Additionally, the propagation of these waves in formations is prone to loss and noise interference, restricting detection to only a few tens of meters around the well. This paper investigates an impulse sound source, a new emission source that can effectively enhance the frequency range and wave energy of traditional sources by generating excitation waves through high-voltage discharges in a fluid-penetrated electrode structure. Firstly, a high-voltage circuit experimental system for the impulse sound source was constructed, and the discharge and response characteristics were experimentally analyzed. Then, four types of needle series electrode structure models were developed to investigate and compare the effects of different electrode structures on the impulse sound source, with the needle-ring electrode demonstrating superior performance. Finally, the needle-ring electrode structure was optimized to develop a ball-tipped needle-ring electrode, which is more suitable for acoustic logging. The results show that the electrode structure directly influences the discharge characteristics of the impulse sound source. After comparison and optimization, the final ball-tipped needle-ring electrode exhibited a broader frequency range—from zero to several hundred thousand Hz—while maintaining a high acoustic amplitude. It has the capability to detect geological areas beyond 100 m and is effective for evaluating micro-fractures and small fracture blocks near wells that require high detection accuracy. This is of significant importance in oil, gas, new energy, and other drilling fields. [ABSTRACT FROM AUTHOR]

The Michigan Basin is composed of geological formations that contain brines and evaporites, and solutes from these geological sources have affected benthic sediment porewater chemistry in Saginaw Bay (Lake Huron). We hypothesize that there exists similar potential for upward solute transport directly from the Michigan Basin into other Great Lakes areas. To test our hypothesis, we present here previously unpublished porewater chemistry analyses from sediment cores collected during multiple Lake Michigan sampling events (spanning 1991–1999) and a new evaluation of previously published data. In several box cores, pore-water chloride concentrations increase with depth, and Cl:Br ratios are consistent with a geological formation brine source. In all gravity cores we collected from southern Lake Michigan, pore-water sodium concentrations increase with sediment depth. At one sample station, pore-water sodium concentrations exceed 2000 mg L−1 within 2 m of the sediment-water interface. Given the pore-water chemistry changes reported here, combined with information from previous studies of Lake Michigan bedrock geology, a Devonian formation brine is a plausible solute source. The presence of saline pore water within glaciolacustrine sediments underlying Lake Michigan indicates that this solute flux has been active during the past 10 k.y. However, the origins of this solute flux, including timing (onset) and contributions from advective and/or diffusive transport, are unknown. The specific geological source and solute transport process are important to resolve in order to evaluate potential effects of these Michigan Basin solute sources on the Great Lakes’ sediment biogeochemistry and water quality. [ABSTRACT FROM AUTHOR]