China Geology最新文献

{"title":"Apatite and zircon (U-Th)/He dating of sandstone in the Weibei Uplift, Ordos Basin and its revealed Eocene rapid uplift denudation event","authors":"Peng Gao , Sheng-biao Hu","doi":"10.31035/cg2023064","DOIUrl":"10.31035/cg2023064","url":null,"abstract":"","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 4","pages":"Pages 797-800"},"PeriodicalIF":4.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Hydrochemistry of the lakes in the southern Badain Jaran Desert and its paleosalinity reconstruction","authors":"Gao-lei Jiang ,&nbsp;Zhe Wang ,&nbsp;Zhen-long Nie ,&nbsp;Zhong-shuang Cheng ,&nbsp;Pu-cheng Zhu ,&nbsp;Le Cao ,&nbsp;Jian-mei Shen","doi":"10.31035/cg2023057","DOIUrl":"10.31035/cg2023057","url":null,"abstract":"<div><div>The reconstruction of paleohydrology, especially paleosalinity, is an important component of paleoenvironmental research. Researches on the modern characteristics of lake water chemistry and the relationship between lake salinity and hydrochemistry are the basis of paleoenvironment reconstruction. The modern hydrochemical characteristics and the relationship between ion composition and salinity of modern lakes are the basis of paleosalinity reconstruction. In this study, hydrochemical analysis of 21 lakes in the Badain Jaran Desert (BJD) was carried out. The relationships between the Sr/Ca and Mg/Ca ratios and total dissolved solids (TDS) were analyzed. The results show that Na⁺, K⁺, Cl⁻ and SO₄²⁻ have high positive correlations with TDS, and Mg²⁺, Sr²⁺, CO₃²⁻ and HCO₃⁻ have lower correlations with TDS. The Sr/Ca and Mg/Ca ratios do not increase linearly with TDS. Hydrochemical analysis indicates that the studied lakes are in the carbonate precipitation stage and that evaporation is the main factor controlling lake evolution in the BJD. The relationships between the Mg/Ca and Sr/Ca ratios and TDS are mainly influenced by lake evolution stage and the hydrochemical types of the lakes. On the basis of comprehensive previous studies, the factors affecting lake evolution, the Mg and Sr partition coefficients and other hydrochemical parameters that change with lake evolution all affect the relationship between chemical composition and salinity. To reconstruct paleosalinity more accurately, more detailed research on the modern hydrochemical characteristics of lakes and the relationship between the element ratios of carbonates and water salinity should be carried out.</div></div>","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 4","pages":"Pages 642-652"},"PeriodicalIF":4.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74511525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Multi-stage formation of the Feragen ophiolite, Norway: Implication from petrology and geochemistry of peridotites and chromitites and its potential for prospecting","authors":"Tian Qiu ,&nbsp;Fa-hui Xiong ,&nbsp;David G. Gee ,&nbsp;Yuan Li ,&nbsp;Jing-sui Yang","doi":"10.31035/cg2023017","DOIUrl":"10.31035/cg2023017","url":null,"abstract":"<div><div>The ultramafic massif of Feragen, which belongs to the eastern ophiolitic belt of Norway, has abundant amounts of chromite ores. Recent studies have revealed a complex melt evolution in a supra-subduction zone (SSZ) environment. This study presents new whole-rock major element, trace element, and platinum-group element chemistry to evaluate their petrogenesis and tectonic evolution. Harzburgites have high CaO, Al₂O₃, TiO₂, MgO, and REE contents corresponding to abyssal peridotites, whereas dunites have low CaO, Al₂O₃, TiO₂, MgO, and REE contents corresponding to SSZ peridotites. The Cr# and TiO₂ of chromian spinels in the harzburgites suggest as much as about 15%–20% melting and the dunites are more depleted with &gt; 40% melting. The harzburgites and the dunites and high-Cr chromitites represent, respectively, the products of low-degree partial melting in a back-arc setting, and the products of melt-rock interaction in a SSZ environment. The calculated ƒO₂ values for dunites and high-Cr chromitites (−0.17 – +0.23 and +2.78 – +5.65, respectively and generally above the FMQ buffer) are also consistent with the interaction between back-arc ophiolites with oxidized boninitic melts in a SSZ setting.</div></div>","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 4","pages":"Pages 686-701"},"PeriodicalIF":4.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"In situ U-Pb dating and trace elements of magmatic rutile from Mujicun Cu-Mo deposit, North China Craton: Insights into porphyry mineralization","authors":"Fan Yang ,&nbsp;Jing-wen Mao ,&nbsp;Wei-dong Ren ,&nbsp;Jia-run Tu ,&nbsp;Gilby Jepson ,&nbsp;Si-yuan Meng ,&nbsp;Zhi-min Wang","doi":"10.31035/cg2023038","DOIUrl":"10.31035/cg2023038","url":null,"abstract":"<div><div>Porphyry Cu (Mo-Au) deposit is one of the most important types of copper deposit and usually formed under magmatic arc-related settings, whilst the Mujicun porphyry Cu-Mo deposit in North China Craton uncommonly generated within intra-continental settings. Although previous studies have focused on the age, origin and ore genesis of the Mujicun deposit, the ore-forming age, magma source and tectonic evolution remain controversial. Here, this study targeted rutile (TiO₂) in the ore-hosting diorite porphyry from the Mujicun Cu-Mo deposit to conduct <em>in situ</em> U-Pb dating and trace element composition studies, with major views to determine the timing and magma evolution and to provide new insights into porphyry Cu-Mo metallogeny. Rutile trace element data show flat-like REE patterns characterized by relatively enrichment LREEs and depleted HREEs, which could be identified as magmatic rutile. Rutile U-Pb dating yields lower intercept ages of 139.3–138.4 Ma, interpreted as post magmatic cooling timing below about 500°C, which are consistent or slightly postdate with the published zircon U-Pb ages of diorite porphyry (144.1–141.7 Ma) and skarn (146.2 Ma; 139.9 Ma) as well as the molybdenite Re-Os ages of molybdenum ores (144.8–140.0 Ma). Given that the overlap between the closure temperature of rutile U-Pb system and ore-forming temperature of the Mujicun deposit, this study suggests that the ore-forming ages of the Mujicun deposit can be constrained at 139.3–138.4 Ma, with temporal links to the late large-scale granitic magmatism at 138–126 Ma in the Taihang Orogen. Based on the Mg and Al contents in rutile, the magma of ore-hosting diorite porphyry was suggested to be derived from crust-mantle mixing components. In conjunction with previous studies in Taihang Orogen, this study proposes that the far-field effect and the rollback of the subducting Paleo-Pacific slab triggered lithospheric extension, asthenosphere upwelling, crust-mantle interaction and thermo-mechanical erosion, which jointly facilitated the formation of dioritic magmas during the Early Cretaceous. Subsequently, the dioritic magmas carrying crust-mantle mixing metallic materials were emplaced and precipitated at shallow positions along NNE-trending ore-controlling faults, eventually resulting in the formation of the Mujicun Cu-Mo deposit within an intracontinental extensional setting.</div></div>","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 4","pages":"Pages 730-746"},"PeriodicalIF":4.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Carbon neutrality: China’s energy transition over the past decade","authors":"Li-qiong Jia ,&nbsp;Xi-jie Chen ,&nbsp;Zi-guo Hao","doi":"10.31035/cg2024086","DOIUrl":"10.31035/cg2024086","url":null,"abstract":"","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 4","pages":"Pages 803-806"},"PeriodicalIF":4.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Metallogenic characteristics of Shitoukengde intrusion and its implications for Ni-Co-(Cu) sulfide mineralization in East Kunlun","authors":"Xue-peng Duan ,&nbsp;Fan-cong Meng ,&nbsp;Zong-qi Wang ,&nbsp;Xiao-fei Yu","doi":"10.31035/cg2023070","DOIUrl":"10.31035/cg2023070","url":null,"abstract":"<div><div>Xiarihamu deposit is the only super-large Ni-Co deposit found in East Kunlun orogenic belt (EKOB) until present. Shitoukengde (STKD) intrusion is considered to have the potential to become a large Ni-Co deposit in East Kunlun. In order to discuss the metallogenic potential, this study present petrographical, geochemical data, and zircon U-Pb dating for the STKD intrusion. The STKD intrusion is hosted within mafic-ultramafic rocks which contain peridotite, pyroxenite and gabbro, and mainly intruded into the marble of the Paleoproterozoic Jinshuikou Group. Harzburgite and orthopyroxenite are the main country rocks for the Cu-Ni sulfide mineralization. Combine with the positive <em>ε</em>_Hf(t) values (+1.1 to +8.6) of zircons, the enrichment of LILEs, depletion of HFSEs, and lower Ce/Pb ratios of whole rocks indicate that the parental magma was originated from the depleted asthenospheric mantle and experienced 5%–15% crustal contamination. Troctolite formed during the Early Devonian and it has weighted mean ²⁰⁶Pb/²³⁸U age of 412 Ma. Regional background information has indicated that the post-collisional extension setting has already existed during the Early Devonian, leading to the formation of STKD intrusion and Cu-Ni sulfide mineralization. STKD intrusion may have the potential to be one economic Cu-Ni sulfide deposit but seems unlikely to be a super-large one.</div></div>","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 4","pages":"Pages 714-729"},"PeriodicalIF":4.6,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Arsenic and fluoride co-enrichment of groundwater in the loess areas and associated human health risks: A case study of Dali County in the Guanzhong Basin","authors":"Rui-ping Liu ,&nbsp;Fei Liu ,&nbsp;Hua-qing Chen ,&nbsp;Yu-ting Yang ,&nbsp;Hua Zhu ,&nbsp;You-ning Xu ,&nbsp;Jian-gang Jiao ,&nbsp;Refaey M El-Wardany","doi":"10.31035/cg2024015","DOIUrl":"10.31035/cg2024015","url":null,"abstract":"<div><div>This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted basin. Key findings are as follows: (1) Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26% and 30%, respectively, of the total samples, with primary hydrochemical type identified as HCO₃-Na. The karst and sand areas exhibit relatively high groundwater quality, serving as preferred sources for water supply. It is recommended that local governments fully harness groundwater in these areas; (2) groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin, which represents the drainage zone of groundwater; (3) arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources; (4) the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks, which are more serious to kids compared to adults. This study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas.</div></div>","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 3","pages":"Pages 445-459"},"PeriodicalIF":4.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419035","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Muscovite 40Ar/39Ar isotopic dating of pegmatite veins in the Bieyesamas rare metal deposit in the Altay Mountain, Xinjiang, northwestern China","authors":"","doi":"10.31035/cg2023044","DOIUrl":"10.31035/cg2023044","url":null,"abstract":"","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 3","pages":"Pages 589-591"},"PeriodicalIF":4.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79772502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Discovery of scheelite in the Zaozigou gold deposit of West Qinling Orogen, Northwest China and its implications for ore genesis","authors":"Meng-xu Guo ,&nbsp;Jia-jun Liu ,&nbsp;De-gao Zhai ,&nbsp;Guo-ming Weng ,&nbsp;Rui Zhu","doi":"10.31035/cg2023099","DOIUrl":"10.31035/cg2023099","url":null,"abstract":"","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 3","pages":"Pages 586-588"},"PeriodicalIF":4.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Depositional process of hyperpycnal flow deposits: A case study on Lower Cretaceous Sangyuan outcrop in the Luanping Basin, Northeast China","authors":"De-zhi Yan ,&nbsp;Ru-kai Zhu ,&nbsp;Hao Shou ,&nbsp;Zhao-hui Xu ,&nbsp;Wei-hong Liu ,&nbsp;Si-cheng Zhu ,&nbsp;Zhi-cheng Lei ,&nbsp;Jing-ya Zhang ,&nbsp;Chang Liu ,&nbsp;Yi Cai ,&nbsp;Huai-min Xu","doi":"10.31035/cg2023096","DOIUrl":"10.31035/cg2023096","url":null,"abstract":"<div><div>Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments. Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin, this paper studies the depositional process of the hyperpycnal flow deposits, and divides their depositional process into three phases, namely, acceleration, erosion and deceleration. In the acceleration phase, hyperpycnal flow begins to enter the basin nearby, and then speeds up gradually. Deposits developed in the acceleration phase are reverse. In addition, the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force. As a result, there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin. In the erosion phase, the reverse deposits are eroded and become thinner or even disappear. Therefore, no reverse grading characteristic is found in the proximal major channel that is closer to the source, but it is still preserved in the middle branch channel that is far from the source. After entering the deceleration phase, normally grading deposits appear and cover previous deposits. The final deposits in the basin are special. Some are reverse, and others are normal. They are superimposed with each other under the action of hyperpycnal flow. The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites, and reasonably explain the sedimentary characteristics of hyperpycnites. It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.</div></div>","PeriodicalId":45329,"journal":{"name":"China Geology","volume":"7 3","pages":"Pages 505-516"},"PeriodicalIF":4.6,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142419038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}