Geological Journal最新文献

{"title":"Sedimentary Environment of the Permian Marine Shale in the Kaijiang-Liangping Trough, Sichuan Basin, China: Implications for Organic Matter (OM) Accumulation","authors":"Tianfu Gu,&nbsp;Shijia Chen,&nbsp;Xiao Chen,&nbsp;Haofei Sun,&nbsp;Feisheng Mou,&nbsp;Jungang Lu,&nbsp;Xiangdong Yin,&nbsp;Lexin Yuan","doi":"10.1002/gj.5064","DOIUrl":"https://doi.org/10.1002/gj.5064","url":null,"abstract":"<div>\u0000 \u0000 <p>The Permian shales in the Kaijiang-Liangping Trough within the Sichuan Basin represent a promising frontier for marine shale gas exploration, whereas there has been limited systematic research on their sedimentary environment and organic matter (OM) enrichment mechanisms. Therefore, we present total organic carbon (TOC) analysis, major/trace element analyses and scanning electron microscope experiments for the Permian marine shales from the trough to determine their paleoenvironmental conditions and influencing factors of OM enrichment. The results show that the paleoclimate changed from dry climate to humid and warm climate (P₃w¹ [the first member of the Wujiaping Formation]) and semi-humid to semi-arid climate (P₃w² [the second member of the Wujiaping Formation]) and P₃d-I (Dalong Formation-I) and then to arid climate again during the shale deposition period from the P₂g (Gufeng Formation) to the P₃d-II. The shales with the highest TOC contents (TOC &gt; 3%, P₃d-I and P₂g), lower TOC contents (TOC &lt; 1%, P₃w¹ and P₃w²) and higher TOC contents (1% &lt; TOC &lt; 2%, P₃d-II) were formed under the control of anoxic environment and high paleoproductivity, oxic-suboxic environment and high paleoproductivity, anoxic-euxinic environment and lower productivity, respectively. Only appropriate sedimentation rates promote OM enrichment. Terrestrial input, paleoclimate, volcanic activity and hydrothermal upwelling mainly indirectly affect OM accumulation by influencing paleoproductivity. The degree of redox conditions is the primary factor affecting OM enrichment, followed by paleoproductivity. Nonetheless, anoxic to euxinic environments are most appropriate for OM preservation. Weak volcanic activity can boost paleoproductivity, but severe volcanic activity might introduce excessive harmful compounds that limit organism survival, resulting in a fall in paleoproductivity. Additionally, element P brought by volcanic ashes doesn't contribute to OM accumulation.</p>\u0000 </div>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3310-3334"},"PeriodicalIF":1.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional static reservoir modelling of Kareem sandstone reservoir, Tawilla Oil Field, at the southern region of Gulf of Suez, Egypt","authors":"Adel A. A. Othman,&nbsp;Mohamed Fathy,&nbsp;Mohamed E. Hashem","doi":"10.1002/gj.5048","DOIUrl":"https://doi.org/10.1002/gj.5048","url":null,"abstract":"<p>The Gulf of Suez, which contains Egypt's oldest oil fields, is one of North Africa's most well-known oil regions. There are more than 80 conventional oil fields in Egypt's Gulf of Suez, some of which have reservoirs that stretch back to the Precambrian and Quaternary. In close proximity to the southern entrance of the Gulf of Suez is the Tawilla West oilfield. The oil field Tawilla West is believed to consist of rotating fault blocks that descend in a south-west direction. The main producing reservoirs are the Miocene section reservoirs, the Belayim and Kareem sandstones. The current research is focusing on the structural elements affecting this giant field to update the field structural model using the newly processed 3D seismic survey, the acquired data from newly drilled wells and the associated different logging techniques. The seismic information quality varied from poor to fair. The quality of the interpreted stratigraphic horizons and geological faults was mainly controlled by the seismic information quality. The research used seismic attribute analyses to improve interpretation and incorporate additional features, enabling better hydrocarbon potential identification and characterization of the reservoirs. Several geological structure contour maps and cross-sections were generated to help in delineating and understanding the reservoir's extension. Based on the detailed correlation study, we were able to detect the faults that affected the structure of the Tawilla West field in detail, define their throw amounts and directions, and identify the missed sections across the studied area. This study introduces an updated model scenario to show the differences and their effect on the field development plan and recommendations. By examining subsurface geologic structural characteristics and evaluating petrophysical data, a 3D static reservoir model was created to resolve structural settings and hydrocarbon trapping, providing detailed information on the field and identifying new opportunities for future development. The research discovered that the updated detailed 3D structural model may support the Kareem Reservoir development plans and encourage drilling, workover and dynamic operations to assign development possibilities in the correct area. According to the established model, there are at least three options in the study's attic areas that might boost oil output and oil reserves for the field while avoiding further failures.</p>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3258-3277"},"PeriodicalIF":1.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing Groundwater Vulnerability to Pollution in a Rapidly Urbanizing River Basin Using a Modified DRASTIC Land Use–Lineament Density Method","authors":"Tsnat Tsegay,&nbsp;Behailu Birhanu,&nbsp;Tilahun Azagegn,&nbsp;Biniyam Tesfaw Hailu,&nbsp;Tenalem Ayenew","doi":"10.1002/gj.5059","DOIUrl":"https://doi.org/10.1002/gj.5059","url":null,"abstract":"<p>Groundwater quality assessment is crucial for ensuring safe drinking water, protecting public health, and maintaining sustainable water resources for agricultural and industrial uses. The Awash River basin faces significant groundwater quality challenges due to rapid population growth, high urbanization, large-scale irrigation, and industrial pollution. The main objective of this study is to evaluate the intrinsic vulnerability of aquifers to pollution in the Awash Basin and identify hotspots requiring urgent intervention using a modified DRASTIC overlay analysis method. In addition to the seven parameters considered in the generic DRASTIC overlay analysis (depth to the water table, recharge, aquifer media, slope, soil media, vadose zone, and hydraulic conductivity), we incorporated land use/land-cover (LULC) and lineament density (LD) distributions (DRASTIC-LU-LD). This modification allowed us to produce more realistic groundwater vulnerability maps for the basin. To identify the most influential parameters in the overlay, sensitivity analysis was conducted using Map Removal Sensitivity Analysis (MRSA) and Single Parameter Sensitivity Analysis (SPSA). Initially, the generic DRASTIC index in the area ranges from 69 to 181, categorizing the area into four vulnerability zones: very low (21%), low (51%), medium (27%), and high (1%). After incorporating LU and LD, the index values ranged from 90 to 240. Based on the percentage of the total area studied, the inclusion of LU decreased the very low and low vulnerability zones from 72% to 44% and the inclusion of LD increased the high- and very-high-vulnerability zones from 14% to 27%. The areas most vulnerable to groundwater pollution are in the western (upper Awash), middle Awash, and northwestern regions, particularly in city centers where groundwater abstraction is significant. These high-vulnerability zones coincide with municipal, industrial, and agricultural pollution sources. The vadose zone parameter has the highest impact in both MRSA and SPSA, with a variation index value of 3.08% and a mean effective weight of 27.93%, respectively. By identifying areas vulnerable to groundwater pollution, this study provides a valuable basis for informed decision-making and the development of effective strategies for protecting groundwater from urban, industrial, and agricultural pollution sources.</p>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3278-3295"},"PeriodicalIF":1.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gj.5059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnesite hosted by the Neoarchean ultramafic rocks in Attappadi, southern India: Insights from spectral and stable isotope investigation","authors":"A Haritha,&nbsp;Asif Iqbal Kakkassery,&nbsp;V. J. Rajesh,&nbsp;Sanjeev Kumar,&nbsp;Mohamed Zaki Khedr","doi":"10.1002/gj.5020","DOIUrl":"https://doi.org/10.1002/gj.5020","url":null,"abstract":"<p>Magnesite is an economically important mineral commonly found in ultramafic complexes worldwide, primarily in Archean to Proterozoic ultramafic complexes. This study focuses on the chemical and spectral characterization of magnesite found in the Neoarchean ultramafic rocks in the Attappadi region in the Southern Granulite Terrane of southern India. The research utilizes x-ray diffraction analysis, hyperspectral, laser Raman, Fourier Transform Infrared, and Isotope Ratio Mass Spectrometry. The studied ultramafic rocks are part of a well-exposed ophiolitic suite known as the Agali ophiolitic complex. Magnesite primarily occurs as veins, veinlets, and lenses within weathered ultramafic rocks. The hyperspectral analysis of the magnesite samples shows absorption bands in the shortwave infrared region, particularly around 2.3 and 2.5 μm, which correspond to the stretching and bending of the C<span></span>O bond in the (CO₃)²⁻ ion in MgCO₃. The laser Raman spectra show intensity peaks at 1095, 738, and 330 cm⁻¹, which may be attributed to the translational and librational vibrations. The Fourier transform infrared data reveal transmittance at 1434, 880, and 747 cm⁻¹, corresponding to Mg<span></span>O bond stretching and asymmetrical C<span></span>O stretching. The x-ray powder diffraction spectra exhibit diffraction peaks at 32°, 35°, 42°, 46° and 53°, characteristic of pure magnesite. The spectroscopic parameters derived from various analyses indicate that the magnesite is high quality and free from gangue minerals. Stable isotope analysis of the magnesite samples yielded δ¹³C values ranging from −5‰ to −9‰ and δ¹⁸O values in the range of 21‰–25‰. The estimated water temperature from which the magnesite has been precipitated is ~59 ± 3.9°C. Based on the field relations, mode of occurrence and isotopic signatures, the mineralization is considered to have been formed by the low-temperature alteration of ultramafic rocks facilitated by CO₂-rich fluids in the near-surface environment. This study compares the characteristics of magnesite from the study area with a few Neoproterozoic serpentinite-hosted magnesite veins in the ophiolitic sequence of the Egyptian Eastern Desert, which is part of the Arabian Nubian shield. The research aims to contribute to understanding magnesite formation in Archaean to Proterozoic mafic–ultramafic rocks on the Earth's crust. It also provides insights into the geological processes that govern the genesis of ultramafic-hosted magnesite globally, particularly in East Gondwana fragments. This information can enhance mineral exploration and resource evaluation in these regions, helping to identify economic prospects and assess the feasibility of magnesite resource extraction and utilization in East Gondwana fragments.</p>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3240-3257"},"PeriodicalIF":1.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The First Report of Late Valanginian–Early Aptian (Early Cretaceous) Ammonites and Chemostratigraphy of Eastern Anatolian, Olur-Erzurum, Türkiye","authors":"Meral Kaya Sarı,&nbsp;Ekrem Kalkan,&nbsp;Seyed Naser Raisossadat","doi":"10.1002/gj.5070","DOIUrl":"https://doi.org/10.1002/gj.5070","url":null,"abstract":"<div>\u0000 \u0000 <p>This study is based on stable isotope analysis of a rich ammonite assemblage from the Sogukcam Formation, which is widely exposed in Yesilbaglar (Olur-Erzurum, NE Türkiye). The presence of ammonid, planktic, and benthic foraminifers in the marine sediments suggests that they are from the early Cretaceous period. The late Valanginian-early Aptian-rich ammonite assemblage includes the following genera and species: <i>Acrioceras</i> sp., <i>Barremites difficilis, Barremites</i> sp., <i>Crioceratites duvalii, Crioceratites</i> sp., <i>Deshayesites</i> aff. <i>dechyi</i>, <i>Deshayesites</i> sp.1, <i>Deshayesites</i> sp.2, <i>Deshayesites</i> sp.3, <i>Deshayesites</i> sp., <i>Dufrenoyia</i> cf. <i>dufrenoyi, Dufrenoyia</i> cf. <i>furcata, Dufrenoyia</i> sp., <i>Hemihoplites</i> sp., <i>Heteroceras</i> sp., <i>Neocomites</i> sp., <i>Phyllopachyceras infundibulum</i>, <i>Protetragonites</i> cf. <i>quadrisulcatus</i>, <i>Protetragonites</i> sp., <i>Ptychoceras</i> sp., <i>Turkmeniceras</i> cf. <i>geokerense,</i> and <i>Turkmeniceras</i> sp. This assemblage suggests that the Sogukcam Formation's deeper facies formed in the late Valanginian to early Aptian period. Fossils and δ¹⁸O data show normal paleosalinity levels. During the late Valanginian-early Aptian period, δ¹⁸O values ranged from −3.67‰ to −2.24‰, with paleotemperatures ranging from 21.3°C to 27.9°C. δ¹³C positive values range from +0.65‰ to +2.86‰. δ¹³C isotope data show the oxygen minimum zone (OMZ) and changes in sea level and productivity. The presence of planktonic foraminifera and the ammonite assemblage indicates that the formation was deposited in warm subtropical waters ranging from the outer shelf to the open sea.</p>\u0000 </div>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"60 1","pages":"33-44"},"PeriodicalIF":1.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Charting Sustainable Future on Energy Security, Financial Development, Natural Resources and Economic Output for Turkey","authors":"Mustafa Necati Coban,&nbsp;Zafer Adali,&nbsp;Oktay Ozkan,&nbsp;Andrew Adewale Alola","doi":"10.1002/gj.5063","DOIUrl":"https://doi.org/10.1002/gj.5063","url":null,"abstract":"<p>The achievement of 16 out of the 123 sustainable development goals (SDGs) indicates the vast task ahead for Turkey. Addressing the aspects of ecological sustainability via the trend of the ratio of biocapacity to ecological footprint, this study seeks to examine whether energy security, financial development, natural resources and economic expansion drive Turkey's load capacity factor. By implementing quantile-on-quantile and its Granger causality dimension, the results largely affirm the statistically significant effect of energy security on the load capacity factor in all quantiles. Although this impact is weak, it is significantly positive, thus indicating that the country's energy security profile is advancing its ecological sustainability. Similarly, globalization positively impacts the load capacity factor by a strong dimension. Conversely, financial development and economic growth exert a significant but negative effect on the load capacity factor in most quantiles, which reflects the undesirability of these indicators on the country's environmental sustainability drive. Specifically, the negative effects of financial development and economic output on the load capacity factor are mainly in the middle to higher quantiles (0.4–0.95) and lowest quantiles (0.05–0.3), respectively. The results of this study can guide the development of intuitive and robust energy efficiency and energy security-related policies.</p>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3296-3309"},"PeriodicalIF":1.4,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/gj.5063","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Waste Generation on the Load Capacity Factor: A Novel Waste Management Assessment for OECD Countries","authors":"Ugur Korkut Pata,&nbsp;Selin Karlilar Pata,&nbsp;Sinan Erdogan","doi":"10.1002/gj.5065","DOIUrl":"https://doi.org/10.1002/gj.5065","url":null,"abstract":"<div>\u0000 \u0000 <p>The increase in global waste generation is an important issue directly addressed in the Sustainable Development Goal (SDG)-12 and OECD countries produce large amounts of waste. In this context, the study examines the influence of waste generated and recycled on the load capacity factor (biocapacity/ecological footprint) in 28 OECD countries from 2000 to 2021 using novel panel data approaches. The study employs augmented mean group and novel half-panel jackknife estimation approaches within the Load Capacity Curve (LCC) hypothesis and confirms the LCC for OECD nations. In addition, the long-term prediction results illustrate that waste generation increases environmental destruction, while waste recycled supports the increase in the load capacity factor. The study recommends policymakers in OECD countries to support economic growth and increase investment in waste recycling technologies to achieve SDG-12.</p>\u0000 </div>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3203-3213"},"PeriodicalIF":1.4,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemistry of Mafic Rocks From the Nagrota–Kathindi Section, Himachal Pradesh, Northwestern Himalaya: A Probable Example of Plume–Lithosphere Interaction","authors":"M. Rajanikanta Singh,&nbsp;Paramjeet Singh,&nbsp;Pratap C. Sethy,&nbsp;A. Krishnakanta Singh","doi":"10.1002/gj.5058","DOIUrl":"https://doi.org/10.1002/gj.5058","url":null,"abstract":"<div>\u0000 \u0000 <p>The Northwest Himalayan region has a record of several phases of mafic magmatic activity spanning from Precambrian to Cenozoic in a dynamic tectonic setting. Here, we studied detailed petrography and new whole-rock geochemistry of mafic volcanic and dykes from the Nagrota–Kathindi Section (NKS), Himachal region of the NW Himalaya, to understand the petrogenesis and possible tectonic setting. Both rock types have comparable mineralogical compositions (clinopyroxene + plagioclase + actinolite-tremolite + chlorite + iron oxides ± hornblende ± epidote ± quartz ± carbonates) overprinted by greenschist to lower amphibolite facies metamorphism. The mafic volcanic and dykes of NKS exhibit subalkaline basalts to basaltic andesites and a typical tholeiite compositional character. The chondrite-normalized rare earth element pattern exhibits similar LREE-enrichment and strong HREE-fractionation, whereas primitive mantle-normalized multi-element patterns show pronounced LILE-enrichment of Rb, Ba, Th, LREE, and HFSE depletion of Nb, K, P, and Ti. The Zr–Y–Nb–Th relationships indicate that both rock types were derived from the plume source, whereas low Nb/La (&lt; 1), similar high large-ion lithophile element concentrations, and pronounced negative Nb, Zr, P, and Ti anomalies suggest that components other than mantle plume must have been involved in the generation and evolution of both rock types, that is, most likely plume and subcontinental lithosphere mantle (SCLM) interaction. The genesis of parent magma for the NKS volcanic and dykes was derived by 4%–6% and 10%–20% partial melting from the spinel + garnet lherzolite stability field. The majority of the studied samples correspond to spinel + garnet peridotite melting on (Gd/Yb)<i>\u0000 _N\u0000 </i> versus CaO/Al₂O₃ diagram, thereby corroborating residual garnet in the mantle restite. All the basalts and dykes from the NK section did erupt/intrude in an intracontinental rift setting based on geochemical discrimination. The key petro-tectonic processes attributed to the formation of these rocks are as follows: (i) the melting of the ascending plume by adiabatic decompression; (ii) the partial melting of this plume–SCLM source in the melting regime, which produces basaltic magma with a tholeiitic composition; and (iii) the release of heat that provides the thermal condition for melting of SCLM and interaction between upwelling mantle plume and subduction metasomatized SCLM.</p>\u0000 </div>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3175-3202"},"PeriodicalIF":1.4,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Are Biofuel Technologies a Revolution for Environmental Sustainability in the United States?","authors":"Selin Karlilar Pata,&nbsp;Ugur Korkut Pata","doi":"10.1002/gj.5057","DOIUrl":"https://doi.org/10.1002/gj.5057","url":null,"abstract":"<div>\u0000 \u0000 <p>Many countries accelerate climate change by using fossil fuels like coal, gas, and petroleum to power their energy production systems and boost economic growth, which in turn releases large amounts of greenhouse gases (GHG). Recently, biofuels (BIO) have gained significant global attention for their potential to decarbonize the economy and reduce dependence on petroleum by replacing fossil fuels. This study examines the effect of biofuel consumption and innovation in non-fossil fuels on the load capacity factor (LCF) in the United States spanning from 1981 to 2020. The empirical outcomes verify the validity of the load capacity curve (LCC) theory. In addition, biofuel consumption has a favourable impact on LCF. The findings further demonstrate that innovation in non-fossil fuel technologies has no significant impact on the LCF. Based on these outcomes, the US government should increase the share of BIO as an energy component in the energy mix to replace fossil fuels. As a result, BIO have significant potential for the United States to meet its low-carbon goal by efficiently reducing GHG.</p>\u0000 </div>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3151-3160"},"PeriodicalIF":1.4,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Petrogenesis of Mafic Dykes in the Beishan Orogen and Its Implications for Subduction of Liuyuan Ocean: Constraints From Geochemistry and Sr-Nd-Hf Isotopes","authors":"Ren Peng,&nbsp;Guishan Zhang,&nbsp;Zhi-Qi Zhao","doi":"10.1002/gj.5061","DOIUrl":"https://doi.org/10.1002/gj.5061","url":null,"abstract":"<div>\u0000 \u0000 <p>Subduction zones are the primary locations of material exchange between the crust and mantle, and thus, arc igneous rocks are extensively examined to explore crust–mantle interactions during oceanic subduction. In this study, the Sr-Nd-Hf isotopic compositions and elemental characteristics of the Yinwaxia mafic dykes from the Shibanshan–Huaniushan arc in the southern Beishan Orogen were investigated to determine their petrogenesis and explore crust–mantle interactions during the subduction of the Liuyuan Ocean. The dykes were subdivided into two groups based on their geochemical composition and spatial distribution. Group I dykes in the northern Yinwaxia area possess depleted light rare earth elements and slightly enriched large-ion lithophile elements, indicated by relatively high ratios of Rb/Nb (1.4–82), Ba/Nb (6–408), and Cs/Nb (0.13–2.74), and low ratios of Th/Yb (0.03–0.39), Th/Nb (0.10–0.83), and (La/Yb)_{\u0000 <i>N</i>\u0000} (0.33–1.36). Further isotopic composition study revealed that low values of (⁸⁷Sr/⁸⁶Sr)_{\u0000 <i>i</i>\u0000} (0.7028–0.7052), and high values of <i>ε</i>\u0000 _Nd(<i>t</i>) (4.9–9.1) and <i>ε</i>\u0000 _Hf(<i>t</i>) (13.2–24.0), which suggests that the mantle source of Group I dykes was metasomatized by aqueous fluids. In Group II dykes located in the southern Yinwaxia area, enrichment of light rare-earth elements and large-ion lithophile elements was observed, featuring lower ratios of Rb/Nb (0.5–16.7), Ba/Nb (13–51), and Cs/Nb (0.15–1.56), but higher ratios of Th/Yb (0.25–2.64), Th/Nb (0.19–1.49), and (La/Yb)_{\u0000 <i>N</i>\u0000} (1.09–2.98) compared to Group I. Furthermore, Group II dykes exhibited higher values of (⁸⁷Sr/⁸⁶Sr)_{\u0000 <i>i</i>\u0000} (0.7051–0.7077) and lower <i>ε</i>\u0000 _Nd(<i>t</i>) (−1.7 to +3.8) and <i>ε</i>\u0000 _Hf(<i>t</i>) (3.7–9.4) isotopic compositions, which suggests that the slab fluids involved in their mantle source were dominated by sediment-derived melts. The difference between the mafic dykes from Groups I and II suggests the addition of steadily increasing amounts of sediment-derived melt in their mantle source; moreover, the increased (La/Yb)_{\u0000 <i>N</i>\u0000} ratio and decreased <i>ε</i>\u0000 _Nd(<i>t</i>) with increasing distance from the Liuyuan mélange are records of the spatial evolution of the composition of the slab fluids during the oceanic subduction of Liuyuan Ocean in the early Permian.</p>\u0000 </div>","PeriodicalId":12784,"journal":{"name":"Geological Journal","volume":"59 12","pages":"3161-3174"},"PeriodicalIF":1.4,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}