Acta Geologica Sinica ‐ English Edition最新文献

{"title":"Seasonal Evolution of Eocene Saline Lakes in Eastern China: A Case Study of ‘Bamboo-like’ Rock Salt in the Shizhai Depression, Northern Jiangsu Province","authors":"Yang XU,&nbsp;Chenglin LIU,&nbsp;Sibo YANG,&nbsp;Yangtong CAO,&nbsp;Longtao WEN,&nbsp;Ruiqin LI","doi":"10.1111/1755-6724.15298","DOIUrl":"https://doi.org/10.1111/1755-6724.15298","url":null,"abstract":"<p>The phenomenon of ‘bamboo-like’ thin interlayers developed in rock salt is one of the most prominent features of Paleogene salt-bearing strata in eastern China, where centimeter-thick rock salts appear separately, forming rhythmic units. At present, detailed analyses of these rhythms of rock salt are still limited, which directly affects the achievement of comprehensive and in-depth understanding of the developmental laws pertaining to this kind of saline lake. Therefore, we selected the typical rhythmic ‘bamboo-like’ rock salts of the Shizhai Depression in Jiangsu Province as the research subject. Through careful observation of rock salts in hand samples and detailed petrographic and mineralogical analyses, we analyzed the hydrogen and oxygen isotopic compositions, homogenization temperatures and chemical compositions of individual fluid inclusions in halite crystals. Early-stage rhythmic deposition was a product of continental saline lake evolution in winter or spring, late-stage rhythmic deposition being the product of evolution in the summer. The seasonal evolution of the halite sequences was determined and two brine enrichment events were identified. In addition, the quiet saline lake environment with concentrated brine represented by rock salt was more likely to precipitate potassium. This study provides a new reference for the evolution of both Paleogene climate and saline lakes in eastern China.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"879-895"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Miocene Pb-Zn Mineralization in the Eastern Gangdese Metallogenic Belt: Evidence from in situ Rb-Sr Dating of Mica and Trace Element Geochemistry of Sphalerite","authors":"Xiaoyan ZHAO,&nbsp;Zhusen YANG,&nbsp;Chang LIU,&nbsp;Yanrui DONG,&nbsp;Haiyan SHI","doi":"10.1111/1755-6724.15310","DOIUrl":"https://doi.org/10.1111/1755-6724.15310","url":null,"abstract":"<p>Four Pb-Zn deposits, namely Bangpu (BP), Digei (DG), Nabuding (NB) and Cuoga (CG), are located within a 20 km distance of each other in the Gangdese porphyry copper belt (GPCB). The age and nature of the Pb-Zn mineralization, especially its relationship to magmatism, remain uncertain. In order to address this issue, mica from the four deposits was selected for in situ Rb-Sr dating, with sphalerite additionally being selected for in situ trace element analysis. Detailed geological research has revealed that the BP and NB deposits are primarily skarn-type Pb-Zn mineralization, while DG and CG are associated with magmatic hydrothermal breccia and are characterized by banded-type mineralization. The Rb-Sr isochron ages of syn-mineralization muscovite at the BP and CG deposits are 11 ± 6 Ma and 19.7 ± 0.7 Ma respectively. Fe, Cd, In, Mn and Sn occur as lattice substitutions in sphalerite from the four deposits. Cu exists as microinclusions in BP, but occurs isomorphically in the DG, NB and CG deposits. The formation temperatures of the four deposits, as calculated from sphalerite geothermometry, range from approximately 200°C to 300°C, indicating that they belong to medium temperature deposits. BP and NB are classified as skarn Pb-Zn deposits, while DG and CG are categorized as hydrothermal filled Pb-Zn deposits. These results suggest that, in addition to porphyry Cu mineralization, the GPCB also contains significant Miocene Pb-Zn mineralization.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"806-821"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acta Geologica Sinica (English Edition) Calls for Submission of Review Papers","authors":"","doi":"10.1111/1755-6724.15316","DOIUrl":"https://doi.org/10.1111/1755-6724.15316","url":null,"abstract":"","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 the Dupangling Granitic Complex, South China: Implications for A-type and Strongly Peraluminous Granite Origin","authors":"Yaohui JIANG,&nbsp;Yajie ZHAO,&nbsp;Yunchao LIU,&nbsp;Boning HAN","doi":"10.1111/1755-6724.15312","DOIUrl":"https://doi.org/10.1111/1755-6724.15312","url":null,"abstract":"<p>Granite origin is crucial to understanding the evolution of continental crust, yet many concerns about granite genesis remain yielding ongoing debates. A new integrated study of petrology, geochronology, mineral chemistry and whole-rock geochemistry of the Dupangling granitic complex in South China, indicate that the granites in the western complex were emplaced during the Caledonian (418 Ma); they have SiO₂ contents of 68.1–70.4 wt%, and are calc-alkaline and strongly peraluminous with high maficity [(TFe₂O₃ + MgO) &gt; 4.0 wt%] and exhibit ⁸⁷Sr/⁸⁶Sr(<i>t</i>) of 0.7234–0.7311 and <i>ε</i>_Nd(<i>t</i>) of –9.0 to –6.7. The granites in the eastern complex, emplaced during the Indosinian (212 Ma), have high SiO₂ contents (73.3–79.8 wt%) and exhibit affinities with A-type granites, such as enrichment in alkalis and rare earth elements (REEs), and depletion in Sr and Ba along with high TFeO/(TFeO + MgO), Ga/Al and Zr + Y + Ce + Nb; these granites exhibit ⁸⁷Sr/⁸⁶Sr(<i>t</i>) of 0.7221 and <i>ε</i>_Nd(<i>t</i>) of –9.2 to –7.5. Geochemical characteristics suggest that the older Caledonian granites were derived through dehydration melting of Paleoproterozoic metasedimentary rocks plus additional (∼20%–32%) input from mafic magma, whereas the Indosinian granites were generated through shallow dehydration melting of the Caledonian granitoids.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"725-742"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origin of the Cretaceous Biluocuo Low-Mg Trachy-Andesites in the Southern Qiangtang Block: Implications for Crust–Mantle Interactions and the Precambrian Basement","authors":"Changjun JI,&nbsp;Chong CHEN,&nbsp;Yuanbing ZOU,&nbsp;Yun CHEN,&nbsp;Lianfeng Zhou,&nbsp;Jiang ZHU","doi":"10.1111/1755-6724.15315","DOIUrl":"https://doi.org/10.1111/1755-6724.15315","url":null,"abstract":"<p>The Cretaceous andesites were discovered in the Biluocuo area, and provided key records to understand the late Mesozoic geodynamic evolution and crustal basement for the southern Qiangtang block in the central Tibet. In this study, we present a detailed study of zircon U-Pb dating, major and trace elemental composition, and Sr-Nd-Hf isotopes for the Biluocuo trachy-andesites. The trachy-andesites yielded zircon U-Pb ages at ca. 97 Ma, and exhibited SiO₂ contents ranging from 55.92 to 69.04 wt%, low TiO₂ contents (0.37 to 0.75 wt%) and low Mg^# values (18.6 to 53.7), suggesting that they belong to high-K calc-alkaline series. They showed adakitic signatures, such as high Sr/Y ratios (almost 24 to 55) and low Y (&lt;20 ppm), implying they were generated at great depths (&gt;15 kbar). The samples have initial Sr isotopic ratios of 0.70963 to 0.70964, <i>ε</i>_Nd(<i>t</i>) values of –4.7 to –4.6, and zircon <i>ε</i>_Hf(<i>t</i>) values of –1.2 to +1.3 with two-stage Hf model ages of 0.95 to 1.09 Ga. Elemental and Sr-Nd-Hf isotopic signatures suggest that the trachy-andesites were derived from the partial melting of the thickened lower crust with involvement of metasomatized mantle components. Combined with coeval high-Mg andesites, we proposed that underplating of mantle induced melting of the lower crust at ca. 97 Ma in the southern Qiangtang block, following by lithospheric delamination. Inherited/xenocrystic zircons from the trachy-andesites revealed magmatic activities at 2562 Ma, 1850–1804 Ma, 1768–1665 Ma, 1043–935 Ma, 851–736 Ma and 642–540 Ma. There is a Precambrian crustal basement in the southern Qiangtang block, which may have experienced the assembly and break-up of the Columbia, Rodinia, and Gondwana supercontinents.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"761-773"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 and Lithium Enrichment Modes of the No. 8 Coal, Late Carboniferous, Eastern Ordos Basin","authors":"Jiaming ZHANG,&nbsp;Yinghai GUO,&nbsp;Ruoyu WANG,&nbsp;Difei ZHAO,&nbsp;Zhibo ZHANG,&nbsp;Zhuoxi LIU,&nbsp;Gaomin QUAN,&nbsp;Jiahui LIU,&nbsp;Dandan LIU","doi":"10.1111/1755-6724.15304","DOIUrl":"https://doi.org/10.1111/1755-6724.15304","url":null,"abstract":"<p>Recent studies have highlighted the presence of lithium enrichment in coals within the Ordos Basin, which has garnered significant attention due to the potential economic value. However, most research has concentrated primarily on the coal seams of the Taiyuan and Shanxi formations, with limited reports on the Benxi Formation. To address this gap, our study focused on elucidating the geochemical characteristics and origins of the lithium enrichment in the No. 8 coal of the Benxi Formation through the use of optical microscopy and inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the No. 8 coal was a bituminous coal, characterized by medium ash yield, low volatile matter, high total sulfur content and medium vitrinite proportion. The No. 8 coal was enriched in Li (average 91.7 ppm, CC = 6.55) and Zr (average 191 ppm, CC = 5.30), the unusual enrichment of Li being primarily located in the middle of the coal. The minerals in the coal were predominantly clay minerals, along with minor amounts of pyrite, quartz and calcite. The occurrence mode of Li in the No. 8 coal was associated with aluminosilicate minerals, presumably kaolinite. Based on geochemical characteristics, the sedimentary source of the No. 8 coal was intermediate-felsic volcanic rock from the Yinshan oldland. The enrichment of Li can be attributed to the supply of terrestrial debris from the Yinshan oldland and the depositional environment. Our analysis identifies three distinct stages of lithium enrichment, emphasizing the critical role played by the terrestrial debris, as well as the acidic to partially reducing conditions, in facilitating this process. In conclusion, our study sheds light on the mechanisms underlying lithium enrichment in the No. 8 coal of the Benxi Formation, highlighting the significance of geological factors in shaping the distribution and concentration of critical metals in coal.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"822-839"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514989","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 and Tectonic Implications of the Kwangsian Orogen: Constraints from Geochemistry and Sr-Nd-Hf Isotopic Compositions of the Early Paleozoic Peraluminous and Aluminous Granitoids in Northern Guangdong, SE China","authors":"Xiaohui JIA,&nbsp;Xiaodi WANG,&nbsp;Xiaofei QIU,&nbsp;Wenqiang YANG","doi":"10.1111/1755-6724.15296","DOIUrl":"https://doi.org/10.1111/1755-6724.15296","url":null,"abstract":"<p>This study presents whole-rock major, trace elements and Sr-Nd-Hf isotopic compositions, as well as zircon U-Pb geochronological data, for the peraluminous and aluminous granitoids in northern Guangdong Province, South China, in order to investigate their petrogenesis and tectonic implications. The Qingzhou granodiorites (458.5–455.4 Ma) are peraluminous (A/CNK = 1.05–1.96). They have relatively high initial ⁸⁷Sr/⁸⁶Sr ratios (<i>I</i>_Sr = 0.7087–0.7148), low <i>ε</i>_Nd(<i>t</i>) values (–11.2 to –10.1) and a variety of zircon <i>ε</i>_Hf(<i>t</i>) values in the range –13.4 to +4.81. By contrast, the Damaoshan granodiorites (458.1 Ma) are metaluminous (A/CNK = 0.79–0.94) in composition, with <i>I</i>_Sr values of 0.7083 to 0.7110, <i>ε</i>_Nd(<i>t</i>) values of –7.92 to –5.28 and zircon <i>ε</i>_Hf(<i>t</i>) values of –8.69 to –2.06. The Gaoshou quartz diorites (449 Ma) are metaluminous-peraluminous. Their <i>I</i>_Sr values vary from 0.7104 to 0.7111 with <i>ε</i>_Nd(<i>t</i>) values from –9.64 to –8.63. Geochemical data and Sr-Nd-Hf isotope compositions indicate that the Qingzhou, Damaoshan and Gaoshou intrusions are primarily derived from the partial melting of metagreywackes, tonalitic rocks and amphibolite, respectively. The crustal materials in northern Guangdong, from top to bottom, consist of Paleozoic sequences, metasediments with a <i>V</i>_p of <i>&lt;</i> 6.0 km/s, metaigneous rocks with a <i>V</i>_p of 6.3–6.7 km/s and amphibolite with a <i>V</i>_p of ∼7.03 km/s.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"707-724"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New Material of the Zalambdalestid Zhangolestes (Mammalia, Zalambdalestidae) from the Late Cretaceous Changchunsaurus Fauna of Jilin, China","authors":"Jun CHEN,&nbsp;Fangyuan MAO,&nbsp;Wenhao WU,&nbsp;Jin MENG","doi":"10.1111/1755-6724.15307","DOIUrl":"https://doi.org/10.1111/1755-6724.15307","url":null,"abstract":"<p>We report new material of the zalambdalestid, <i>Zhangolestes jilinensis</i>, from the Quantou Formation (lower Upper Cretaceous, Cenomanian to Turonian), Gongzhuling City, Jilin Province, NE China. Using micro-CT-scan, the material is shown to include dentocranial and postcranial elements recovered from the same matrix block containing the holotype specimen. The CT-images also show the labial and internal structures of the holotype fragment of the lower jaw of <i>Z. jilinensis</i>. Based on the preservation, relative size, and tooth wear, the new material and the holotype lower jaw likely belong to the same individual animal, whereas the hypodigm mandibular fragment assigned to <i>Z. jilinensis</i> in the original study is thought now to belong to a different individual, potentially representing a different species, which, if true, would increase the eutherian diversity in the Late Cretaceous <i>Changchunsaurus</i> Fauna. Furthermore, the new CT-images show that the incisor morphology is diverse within zalambdalestids and probably evolved independently from the enlarged incisors in placental mammals, such as Glires.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"634-645"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144515124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variation of Heteroatomic Compounds from the First Member of the Upper Cretaceous Qingshankou Formation in the Sanzhao Sag, Songliao Basin (NE China) using ESI FT-ICR MS and its Shale Oil Geological Significance","authors":"Fei XIAO,&nbsp;Jianguo YANG,&nbsp;Yulai YAO,&nbsp;Shichao LI,&nbsp;Yiming HUANG,&nbsp;Xiaoyong GAO","doi":"10.1111/1755-6724.15299","DOIUrl":"https://doi.org/10.1111/1755-6724.15299","url":null,"abstract":"&lt;p&gt;Organic-rich mudstones and shales, which hold significant potential for shale oil resources, characterize the first member of the Upper Cretaceous Qingshankou Formation (K&lt;sub&gt;2&lt;/sub&gt;&lt;i&gt;qn&lt;/i&gt;&lt;sup&gt;1&lt;/sup&gt;) in the Sanzhao sag of the Songliao Basin, NE China. Focusing on 30 core samples obtained from the first shale oil parameter well, named SYY3 in the study area, we systematically analyzed the composition and stratigraphic distribution of the K&lt;sub&gt;2&lt;/sub&gt;&lt;i&gt;qn&lt;/i&gt;&lt;sup&gt;1&lt;/sup&gt; heteroatomic compounds using electrospray ionization Fourier transform–ion cyclotron resonance mass spectrometry (ESI FT-ICR MS), to assess their geological relevance to shale oil. The findings indicate that in the negative ion mode, the heteroatomic compounds predominantly consist of N&lt;sub&gt;1&lt;/sub&gt;, N&lt;sub&gt;1&lt;/sub&gt;O&lt;sub&gt;1&lt;/sub&gt;–N&lt;sub&gt;1&lt;/sub&gt;O&lt;sub&gt;8&lt;/sub&gt;, O&lt;sub&gt;1&lt;/sub&gt;–O&lt;sub&gt;8&lt;/sub&gt;, O&lt;sub&gt;1&lt;/sub&gt;S&lt;sub&gt;1&lt;/sub&gt;–O&lt;sub&gt;6&lt;/sub&gt;S&lt;sub&gt;1&lt;/sub&gt;; contrastingly, in the positive ion mode, they are primarily composed of N&lt;sub&gt;1&lt;/sub&gt;–N&lt;sub&gt;2&lt;/sub&gt;, N&lt;sub&gt;1&lt;/sub&gt;O&lt;sub&gt;1&lt;/sub&gt;–N&lt;sub&gt;1&lt;/sub&gt;O&lt;sub&gt;4&lt;/sub&gt;, N&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;1&lt;/sub&gt;, O&lt;sub&gt;1&lt;/sub&gt;–O&lt;sub&gt;4&lt;/sub&gt;, O&lt;sub&gt;1&lt;/sub&gt;S&lt;sub&gt;1&lt;/sub&gt;–O&lt;sub&gt;2&lt;/sub&gt;S&lt;sub&gt;1&lt;/sub&gt;. Heteroatomic compound distributions vary significantly with depth in the negative ion mode, with minor variations in the positive ion mode. These distributions are categorized into three types based on the negative ion ratio ((N&lt;sub&gt;1&lt;/sub&gt; + N&lt;sub&gt;1&lt;/sub&gt;O&lt;sub&gt;x&lt;/sub&gt;)/O&lt;sub&gt;x&lt;/sub&gt;): Type I (&gt;1.5), Type II (0.8–1.5), and Type III (&lt;0.8); types I and II generally exhibit a broader range of carbon numbers compared to Type III. The distribution of double bond equivalent (DBE) values across various sample types exhibits minimal variance, whereas that of carbon numbers shows substantial differences. Variations in heteroatomic compound compositions among the samples might have resulted from vertical sedimentary heterogeneity and differing biotic contributions. Type III samples show a decrease in total organic carbon (TOC) and free oil content (&lt;i&gt;S&lt;/i&gt;&lt;sub&gt;1&lt;/sub&gt;) compared to types I and II, but an increased oil saturation index (OSI), indicating a lower content of free oil but a higher proportion of movable oil. The reduced content of N-containing compounds implies lower paleolake productivity during deposition, leading to a reduction in TOC and &lt;i&gt;S&lt;/i&gt;&lt;sub&gt;1&lt;/sub&gt;. A lower TOC can enhance oil movability due to reduced oil adsorption, and the decreased presence of polar nitrogenous macromolecules with fewer high-C-number heteroatomic compounds further promote shale oil movability. Additionally, the negative ion ratios of N&lt;sub&gt;1&lt;/sub&gt;/N&lt;sub&gt;1&lt;/sub&gt;O&lt;sub&gt;1&lt;/sub&gt; and O&lt;sub&gt;2&lt;/sub&gt;/O&lt;sub&gt;1&lt;/sub&gt; exhibit positive and negative correlations with the values of TOC, &lt;i&gt;S&lt;/i&gt;&lt;sub&gt;1&lt;/sub&gt;, and extractable organic matter (EOM), respectively, indicating that the salinity and redox conditions of the depositional water body are the primary controlling factors for both organic matter en","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"840-861"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tourmaline and Mica Chemistry of the Wangxianling Granitoids, South China: Implications for Petrogenesis of Highly Fractionated Granite","authors":"Xiaoxia DUAN,&nbsp;Ziyi WANG,&nbsp;Bin CHEN,&nbsp;Lingli ZHOU,&nbsp;Zhiqiang WANG,&nbsp;Yanjiao CHEN","doi":"10.1111/1755-6724.15311","DOIUrl":"https://doi.org/10.1111/1755-6724.15311","url":null,"abstract":"<p>Both fractional crystallization and fluid-melt-crystal interaction are involved in the formation of highly fractionated granites. This paper assessed those two processes using geochemistry of muscovite and tourmaline and bulk-rock chemistry of multi-phase Wangxianling granitoids, South China. Compositional variations suggest the coarse-grained muscovite granite is produced from fractional crystallization of the two-mica granite whereas the fine-grained muscovite granite represents a distinct magma pulse. Progressive fractionation of quartz, feldspar and biotite leads to elevated boron and aluminum content in melt which promoted muscovite and tourmaline to crystallize, which promotes two-mica granite evolving towards tourmaline-bearing muscovite granite. Fluid-melt-crystal interaction occurred at the magmatic-hydrothermal transitional stage and resulted in the textural and chemical zonings of tourmaline and muscovite in finegrained muscovite granite. The rims of both tourmaline and muscovite are characterized by the enrichment of fluid mobile elements such as Li, Mn, Cs and Zn and heavier <i>δ</i>¹¹B values of the tourmaline rims (–15.0‰ to –13.6‰) compared to cores (–15.7‰ to –14.3‰). Meanwhile, significant M-type REE tetrad effects (TE_1,3 = 1.07–1.18) and low K/Rb ratios (48–52) also correspond to fluid-melt-crystal interaction. This study shows zoned muscovite and tourmaline can be excellent tracers of fractional crystallization and late-stage fluid-melt-crystal interaction in highly evolved magmatic systems.</p>","PeriodicalId":7095,"journal":{"name":"Acta Geologica Sinica ‐ English Edition","volume":"99 3","pages":"789-805"},"PeriodicalIF":3.5,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}