Hasil untuk "Geology"

S. F. Lytvyniuk, S. O. Paiuk

Analytical studies on the assessment of mineral raw material resources (MRM) in the context of the circular and resource-efficient (low-carbon) economy development at the global and regional level have revealed a number of problematic issues. Abovementioned problems are related to the assessment method (classification) and various approaches to MRM accounting and management. The application of different classification systems, approaches to accounting and permitting procedures for the project development complicates the formation of a unified strategy for achieving sustainable development goals (SDGs) in the field of MRM supply and management, in particular, in the United Nations Economic Commission for Europe (UNECE) region. Considering the practical experience of applying the United Nations Framework Classification for Resources (UNFC) in Ukraine, as well as results of the research conducted by the Expert Group on Resource Management of the UNECE Committee on Sustainable Energy, in addition to a comprehensive analysis of the current state, methodological approaches to the “harmonization” of classification features and accounting of MRM deposits assessed based on standards that have lost their relevance have been suggested in the article. Presented studies on classification systems and accounting approaches indicate the necessity and relevance of creating single (unified) approaches to the MRM assessment and management. Developed methodological approaches to the actualization of the undistributed subsoil fund of Ukraine include the compliance of recorded reserves with the Classification of Mineral Reserves and Resources of the State Subsoil Fund based on three fundamental criteria: determination of the degree of geological knowledge (Axis G); clarification of the degree of feasibility study (Axis F); and by the commercial significance (Axis E).

Mohammed Abed, Sawsan Al-Hazaa, Muyasser Jomaa’h

The present study depends on two types of concrete: the first and second samples belong to Portland cement with a high strength of 52.5 R, and ordinary Portland cement with a normal strength of 42.5 N, respectively. The physical tests for these two samples according to Iraqi Standard Specification No. 5 of 2019 were conducted. Whereas the third and fourth samples of concrete waste were taken from Mosul City and Al-Anbar Governorate. The concrete waste samples were broken into different-size particles as a fine and coarse aggregate using a mechanical crusher (Los Angeles). According to the Iraqi Standard Specification No. 45 (1984, the Physical and chemical tests for both fine and coarse natural aggregate and recycled concrete waste were conducted. The physical and mechanical results of the recycled aggregate testing samples were found to be within the limits of specifications, in which a reference concrete was made from the standard cement samples with natural aggregate for comparison. The natural aggregate was replaced with 100% recycled aggregate, and its behavior was studied through mechanical properties tests, including compressive strength, flexural resistance, and direct tensile resistance within 7 and 28 days. The results show a decrease in the compressive, flexural, and direct tensile strength in the subjected samples compared to the reference specimens. The study concluded that a 100% replacement ratio of coarse and fine recycled aggregate can be used successfully with different types of cement to obtain a new type of concrete that can be used in several engineering fields. The mechanical properties of the new concrete depend mainly on the type, class and quality of the natural cement even on the properties of the recycled aggregate.

Cvetković Vladimir M., Gole Stefan, Renner Renate et al.

This research is dedicated to a comprehensive exploration of the strengths and weaknesses inherent in the legal and institutional measures established to safeguard cultural heritage in the Republic of Serbia against the adverse effects of disasters, including earthquakes, landslides, rockfalls, floods, torrents, storms, hail, and forest fires. The study seeks to identify key challenges and shortcomings within the existing legal and institutional framework while also highlighting and analyzing best practices and potential avenues for improvement in the protection system. The research posits a preliminary hypothesis suggesting that significant challenges exist within the current framework, potentially hindering effective response and recovery efforts following natural hazards. Data collection involved semi-structured interviews with field experts and an in-depth analysis of existing documentation. These methods were aimed at gathering critical data and insights to enhance the understanding of systemic issues and contribute to developing practical, viable solutions. The analysis and processing of the collected data were conducted using ATLAS. ti software, enabling a detailed and systematic examination of qualitative information. Moreover, assessing the current capacity of institutions to respond swiftly and effectively to natural hazards that threaten cultural heritage formed a central aspect of this study. The findings reveal notable deficiencies in the legal framework, inadequate institutional capacities, limited resources, and insufficient training for disaster response. The results underscore the pressing need for improved inter-institutional cooperation and the development of technical and logistical capabilities. To address these issues, the study recommends aligning legal frameworks with international standards, securing increased funding for technical resources, and implementing specialized training programs for institutional staff. This article makes a significant contribution to advancing the understanding and enhancement of the cultural heritage protection system in Serbia, offering actionable insights and a robust foundation for further research and strategic development in this critical area.

Rungroj Arjwech, Sutatcha Hongsresawat, Suriyachai Chaisuriya et al.

Identifying the movement of the branches of the hidden Thakhek fault in Thailand is challenging due to the absence of evident landforms indicating an active fault. In this study, we analyzed a digital elevation model (DEM) to identify potential landforms. A 2D Electrical Resistivity Tomography (ERT) survey was conducted to locate the hidden Thakhek fault. The results reveal vivid images of resistivity contrast, interpreted as two reverse faults, with mudstone exhibiting low resistivity in the middle, flanked by thick sediment layers with higher resistivity. Three trenches were excavated perpendicular to the two interpreted reverse faults. The displacement of reverse faulting appears to have shifted mudstone over Quaternary sediments, with vertical offsets revealed in trenches NWY-1, NWY-2, and NWY-3. This movement could be identified as a positive flower structure. Additionally, lakes are identified as a negative flower structure along the traces. These features result from strike-slip strains under a locally appropriate compressional and extensional environment in a shearing strike-slip fault.

Yihui Xiong, R. Zuo, E. Carranza

Abstract Identification of anomalies related to mineralization and integration of multi-source geoscience data are essential for mapping mineral prospectivity. In this study, we applied big data analytics and a deep learning algorithm to process geoscience data to identify and integrate anomalies related to skarn-type Iron mineralization in the southwestern Fujian metallogenic zone of China. Based on the geological setting and environment for the formation of skarn-type Iron mineralization, 42 relevant variables, including two geological, one geophysical, and 39 geochemical variables, were analyzed and integrated for detecting anomalies related to mineralization using a deep autoencoder network. The results indicate that the mapped prospectivity areas have a strong spatial relationship with the locations of known mineralization and demonstrate that big data analytics supported by deep learning methods is a potential technique to be considered for use in mineral prospectivity mapping.

Z. Pan, Jianping Ye, F. Zhou et al.

ABSTRACT Coal reservoirs especially deep unminable coal reservoirs, are viable geological target formations for CO2 storage to mitigate greenhouse gas emissions. An advantage of this process is that a large amount of CO2 can be stored at relatively low pressure, thereby reducing the cost of pumping and injection. Other advantages include the use of existing well infrastructure for CO2 injection and to undertake enhanced recovery of coalbed methane (ECBM), both of which partially offset storage costs. However, ECBM faces difficulties such as low initial injectivity and further permeability loss during injection. Although expensive to perform, ECBM field experiments are essential to bridge laboratory study and large-scale implementation. China is one of the few countries that have performed ECBM field experiments, testing a variety of different geological conditions and injection technologies. These projects began more than a decade ago and have provided valuable experience and knowledge. In this article, we review past and current CO2 ECBM field trials in China and compare with others performed around the world to benefit ECBM research and inform future projects. Key aspects of the ECBM field projects reviewed include the main properties of target coal seams, well technologies, injection programmes, monitoring techniques and key findings.

C. Hsein Juang, Jie Zhang, Mengfen Shen et al.

Abstract There are typically three types of models involved in a geotechnical analysis, i.e., the geologic model, the ground model, and the geotechnical model, each of which may be associated with uncertainty to a different extent. However, in a typical geotechnical analysis the geological uncertainty is seldom characterized and considered explicitly. In this paper, we discuss the probabilistic tools developed in the geotechnical profession for tasks such as uncertainty characterization, assessment of impact of uncertainties, uncertainty reduction, and evaluation of the value of uncertainty reduction. We postulate that the same tools may be used for a unified treatment of various types of uncertainties in a geotechnical analysis, which would necessitate the collaboration of the engineering geologists and the geotechnical engineers to comprehensively characterize these uncertainties consistently. To this end, the probabilistic tools or methods that are widely used in geotechnical engineering are examined to determine their applicability in the evaluation of geological uncertainties. Examples are provided to illustrate various concepts introduced in this paper.

D. Galloway, David R. Jones, S. Ingebritsen

P. Calcagno, J. Chilès, G. Courrioux et al.

J. Ivonne Martínez-Valdés, Víctor Hugo Márquez-Ramírez, Velio Coviello et al.

The Volcán de Colima, one of the most active volcanoes in Mexico, has experienced several volcanic crises over the last century with the emplacement of voluminous block-and-ash flow deposits providing large volumes of loose material along the main ravines. During the rainy season, this material is easily eroded forming lahars. Over 40 events with variable magnitude (105-106 m3) have been detected each year. The largest events that cause damages to infrastructure are usually triggered during the hurricane season (from mid-August to October) when more than 250 mm of rain usually are accumulated over a few days. On 23 October 2015, Hurricane Patricia hit the Volcán de Colima. The hurricane was announced as having reached category 5 thereby representing the largest ever recorded hurricane event in Mexico. It rapidly weakened after landfall but followed a straight trajectory toward the volcano. Up to 400 mm of rain were recorded over 30 hours. The event was recorded at a monitoring station located in the middle reaches of the La Lumbre ravine on the SW flank of the volcano, which was equipped with a rain gauge, a geophone (10 Hz), and a video camera. A multi-pulse lahar started around 8 pm (GMT) and lasted for more than five hours. The seismic signal and the video images were analyzed to identify the timing of the main pulses, the sediment concentrations, and maximum flow peak discharge. Data show that the lahar was characterized by three main pulses, in the range of debris flows with maximum flow-depth of 8 m, interspersed by more dilute tails as hyperconcentrated flow, as also observed from the frequency contents of the seismic signal. A total volume of 2.5 × 106 m3 was estimated based on the strong correlation between the seismic amplitude and the flow discharge. The lahar destroyed one bridge and ~500 m of the interstate road leaving several villages cut off for a few days. Based on the flow magnitude, duration, and the associated damage, this event probably represents the largest one recorded over the last 20 years. The FLO-2D model was used to replicate the observed event to estimate the maximum inundation limits of lahars along the five principal ravines of the volcano, in an attempt to design a hazard map for catastrophic hurricane-induced events.

Tito Arosio, Stéphane Affolter, Kurt Nicolussi et al.

The importance of the stable isotopes in tree rings for the study of the climate variations caused by volcanic eruptions is still unclear. We studied δ¹⁸O, δD, δ¹³C stable isotopes of larch and cembran pine cellulose around four major eruptions with annual resolution, along with a superposed epoch analysis of 34 eruptions with 5-year resolution. Initial analysis of the tropical Tambora (1815 CE) and Samalas (1257 CE) eruptions showed a post-eruption decrease in δ¹⁸O values attributed to post-volcanic cooling and increased summer precipitation in Southern Europe, as documented by observations and climate simulations. The post-volcanic cooling was captured by the δD of speleothem fluid inclusion. The δ¹⁸O decrease was also observed in the analysis of 34 major tropical eruptions over the last 2000 years. In contrast, the eruptions of c. 750, 756, and 764 CE attributed to Icelandic volcanoes left no significant responses in the cellulose isotopes. Further analysis of all major Icelandic eruptions in the last 2000 years showed no consistent isotopic fingerprints, with the exception of lower post-volcanic δ¹³C values in larch. In summary, the δ¹⁸O values of cellulose can provide relevant information on climatic and hydroclimatic variations following major tropical volcanic eruptions, even when using the 5-year resolution wood samples of the Alpine Tree-Ring Isotope Record database.

P. Atkinson, R. Massari

F. Meer, H. Werff, F. V. Ruitenbeek

R. Ernst

Large igneous provinces (LIPs) are intraplate magmatic events, involving volumes of mainly mafic magma upwards of 100,000 km3, and often above 1 million km3. They are linked to continental break-up, global environmental catastrophes, regional uplift and a variety of ore deposit types. In this up-to-date, fascinating book, leading expert Richard E. Ernst explores all aspects of LIPs, beginning by introducing their definition and essential characteristics. Topics covered include continental and oceanic LIPs; their origins, structures, and geochemistry; geological and environmental effects; association with silicic, carbonatite and kimberlite magmatism; and analogues of LIPs in the Archean, and on other planets. The book concludes with an assessment of LIPs' influence on natural resources such as mineral deposits, petroleum and aquifers. This is a one-stop resource for researchers and graduate students in a wide range of disciplines, including tectonics, igneous petrology, geochemistry, geophysics, Earth history, and planetary geology, and for mining industry professionals.

G. Erdi-Krausz, M. Matolín, B. Minty et al.

Kathryn Yusoff

The diagnostic of the Anthropocene proposes a new geological epoch that designates humans as beings capable of geomorphic force, shaping Earth systems on a par with inhuman forces. This social geology marks an ascendance to inhuman planetary power fuelled by fossil fuels from the Carboniferous. Yet nowhere are the geophysical, genomic, and social narratives of this geologic subjectification considered together to interrogate these geologic capacities, not just in terms of impacts on the Earth, but as forces that subjects share—geologic forces that compose and differentiate corporeal and collective biopolitical formations. I argue in this paper that the concept of the Anthropocene is axiomatic of new understandings of time, matter, and agency for the human as a collective being and as a subject capable of geomorphic acts; a being that not just affects geology, but is an intemperate force within it. This immersion of humanity into geologic time suggests both a remineralisation of the origins of the human and a shift in the human timescale from biological life course to that of epoch and species—life. The paper is structured as a modest conversation between two fossilised subjects that define the imagined origin and ending of the narrative arc of the Anthropocene—one from the prehistory of human origins, the other from the future of the Anthropocene—in a conversation about time, geology, and inhuman becomings. Examining fossils as material and discursive knots in the narrative arc of human becoming, I argue for a ‘geological turn’ that takes seriously not just our biological (or biopolitical) life, but also our geological (or geopolitical) life and its forms of differentiation. Fossils unlock this life—death, time—untimely, corporeal—incorporeal equation, suggesting the need for a theory of the geologic and a reckoning with the forces of mute matter in lively bodies: a corporeality that is driven by inhuman forces. This paper investigates what I am calling “geologic life”—a mineralogical dimension of human composition that remains currently undertheorised in social thought and is directly relevant for the material, temporal, and corporeal conceptualisation of fossil fuels. This geologic life prompts a need to rethink the coherency of the human as a territorialising force of the Earth in its prehistoric, contemporary, and future-orientated incarnation. As such, this paper proposes a speculative theoretical framework for thinking modes of geologic life within the Anthropocene.

Haoyue Zhang, Wenbo Liu, Xujiao Zhang et al.

Hetao Plain is one of the most serious area of local arsenic poisoning in China.Based on shallow groundwater arsenic samples, the paper used the semivariogram to reveal the spatial distribution and heterogeneity of groundwater arsenic concentration, and further discussed the influencing factors.The results show that the arsenic concentration in groundwater generally increases from south to north in the Hetao Plain.The residual groundwater arsenic concentration is fitted to the pure nugget effect model under the assumption of isotropic conditions, which means it is random on the measured scale, so there is no spatial autocorrelation and the variance is great in short distances.The fractal dimension value is large(D=1.999), further indicating the distinct variation of groundwater arsenic concentration within the measured scale.Groundwater arsenic is closely related to organic matters in sediments.Since the Late Quaternary, the tectonic movements of the northern mountains and changes in the sedimentary environment of the basin has caused multiple sedimentary facies, resulting in a high degree of spatial variability in burial conditions of organic matters.The high spatial variability of organic matters characteristics further leads to high spatial variability of groundwater arsenic concentration.The slow groundwater flow plays an important role in maintaining this pattern.This article focuses on the spatial heterogeneity of groundwater arsenic in the Hetao area, which has scientific significance for effectively predicting the potential risk of arsenic exposure in drinking water in unknown areas, accurately preventing endemic diseases and ensuring water supply safety.

Kozlenko M.V.

A density modeling of the north-western shelf of the Black Sea along 31°20’ E was carried out. According to its results, a complex block structure of the area is determined, which is closely connected with the history of its development. Signs of Baikal tectonic activation of the southern edge of the pre-Riphean Eastern European platform, as well as the adjacent part of the Scythian plate have been revealed. Areas formed during the Hercynian and Cimmerian epochs of tectogenesis have been identified within the Scythian plate. At the base of the Karkinit Trough, two areas of reduced crust resulting from riftogenesis with varying degrees of intensity of basification have been established. Two ancient volcanos of ryolite composition were found on the basement surface on the northern slope of the Kalamit swell. It is highly probable that the Gamburtsev uplift is an eastern extension of the Gubkin swell. According to the structure and value of the calculated densities, it is established that the Gamburtsev uplift is a «blind» mud volcano, which was formed during the second stage of the late Cimmerian cycle and was active throughout the Cretaceous period. A detailed analysis of the deep structure and fault tectonics of the local structures of the sedimentary cover in the intersection of the profile and the area of gas seeps was carried out. It was found that the Flangova, Partizanska and Hamburtseva structures are more promising for hydrocarbon accumulation. The hydrocarbon potential of the Ushakov structure (H-41) is questionable, because structurally and tectonically it is analogous to the Delphin structure, which was deemed unproductive based on drilling results. The area of gas seeps was found to be confined to a mantle fault, which separates two blocks with distinctly different structures and Meso-Cenozoic evolution of the Earth’s crust. It is proposed to conduct a detailed seismic survey in this area in order to identify local structures in the sedimentary cover, promising for hydrocarbons.

Li Wang, Yuanhuizi He, Yuelin Zhang et al.

In this study, based on the EM-DAT (The Emergency Events Database) database, disaster assessment for the “Belt and Road” region was carried out in relation to the $${\rm{SD}}{{\rm{G}}_{13.1.1}}$$ indicator of the Sustainable Development Goals (SDGs) agenda launched in 2015. A new method for diagnosing trends in the $${\rm{SD}}{{\rm{G}}_{13.1.1}}$$ indicators based on the Theil-Sen median method is proposed. In addition, using the data available in the EM-DAT, an overview of disaster records is used to quantify disasters for a total of 73 countries. The disaster trends for the period 2015‒2019 were found to demonstrate the following. (1) As a result of geological and climate conditions, Asia and Africa are high-risk disaster areas and disasters have caused considerable economic losses and affected the populations in developing and underdeveloped countries in these regions. (2) The clear positive value of $$\Delta {\rm{s}}13.1.1$$ found for China reflects the country’s encouraging achievements in disaster prevention and mitigation. (3) The value of $${\rm{SD}}{{\rm{G}}_{13.1.1}}$$ was observed to be increasing in South Asia, northwest Africa and South Africa, with the increase in India and Mauritania being the most serious. The new method proposed in this paper allows the real trend in the $${\rm{SD}}{{\rm{G}}_{13.1.1}}$$ indicator in various countries to be derived and provides critical intelligence support for international disaster risk reduction plans and sustainable development goals.

Wenjia Li, Kai Ma, Qinjun Qiu et al.

Abstract Chinese word segmentation (CWS) is the foundational work of geological report text mining and has an important influence on various tasks, such as named entity recognition and relation extraction. In recent years, the accuracy of the domain‐general CWS model has been limited by the domain and large scale of the training corpus, especially data on Chinese geological texts. Training these CWS models also requires much manually annotated data, which takes a large amount of time and effort. When applying these existing models/methods directly to the geoscience domain, the segmentation accuracy and performance will drop dramatically. To address this problem, we pretrain the Bidirectional Encoder Representations from Transformer (BERT), which can leverage unlabeled domain‐specific knowledge, on unlabeled Chinese geological text and then input them into a Bidirectional long short‐term memory and Conditional random field (BiLSTM‐CRF) model for extracting text features. Finally, the predicted tags are decoded by the CRF. The experimental results show that the F1 score of the proposed model reaches 96.2% on the constructed test set of geological texts. Additionally, experiments illustrate that our proposed model achieves comparable performance to that of other state‐of‐the‐art models, and the proposed cyclic self‐learning strategy can be further extended to other domains.