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| 1 | 扬子陆块古-中元古代地质演化与Columbia超大陆重建显示文摘扬子陆块在古-中元古代时期经历了较为强烈的岩浆-变质-沉积-成矿等地质事件,这些事件是理解该陆块陆壳演化和成矿效应内在联系及动力学的关键,也是探讨该陆块在Columbia超大陆中古地理重建的前提。本文以古-中元古代地质单元出露较为完整的扬子西南缘为重点研究对象,在总结已有资料的基础上,对扬子陆块古-中元古代时期地质事件进行剖析和讨论,明确了扬子陆块西南缘在古-中元古代时期经历了由Columbia超大陆初始裂解引起的陆内裂谷相关的沉积作用,岩浆侵位及矿产富集等地质过程。通过与全球陆块进行对比,发现相似的裂谷的相关沉积-岩浆-成矿事件在劳伦大陆西北部、澳大利亚北部及Siberian克拉通都有体现。本文认为扬子陆块在2. 4~2. 3 Ga通过增生拼贴到劳伦大陆Rae克拉通。在共同经历过Columbia超大陆聚合的峰期变质作用(2. 03~1. 81 Ga)之后,超大陆开始逐步裂解并形成大陆内部裂谷,最终在古元古代后期(~1. 66~1. 60 Ga)扬子陆块和Columbia超大陆主体分离。 | 王伟 卢桂梅 黄思访 薛尔堃 | 2019 | 矿物岩石地球化学通报2019，38，1： | 18 |
| 2 | 扬子克拉通古元古代冷俯冲低温-高压榴辉岩相变泥质岩的发现及其大地构造意义显示文摘首次报道了扬子克拉通黄陵穹隆北部崆岭杂岩古元古代水月寺混杂岩带中发现特征性石榴石-蓝晶石-硬绿泥石组合低温-高压(LT-HP)榴辉岩相变泥质岩,其变质峰期矿物组合为石榴石+蓝晶石+硬绿泥石+多硅白云母+金红石+石英.相平衡模拟计算得到一条近等温减压的顺时针型变质P-T轨迹,其峰期变质条件为571~576℃,19.2~21.8 kbar.LAICP-MS锆石U-Pb年代学研究获得变泥质岩中碎屑锆石核部年龄集中于2.1~2.2 Ga,变质增生边年龄为1 991±20 Ma.GrtKy-Cld组合榴辉岩相变泥质岩原岩形成构造环境和变质峰期条件指示,其形成于较低地温梯度(d T/d P≈300°C/GPa)下的活动大陆边缘冷俯冲构造环境,进一步表明至少从古元古代开始具有'冷俯冲'构造特征的现代板块构造体制已经启动. | 韩庆森 彭松柏 焦淑娟 | 2020 | 地球科学2020，45，6： | 7 |
| 3 | Geochronological and Geochemical Constraints on the Petrogenesis of Early Paleoproterozoic(2.40–2.32 Ga) Nb-Enriched Mafic Rocks in Southwestern Yangtze Block and Its Tectonic Implications显示文摘Recent geological survey has identified the Early Paleoproterozoic meta-mafic intrusions in the southwestern Yangtze Block.We present geochronological,whole-rock geochemical and Nd isotopic data for these meta-mafic rocks to better address the tectonic evolution of the Yangtze Block during the Early Paleoproterozoic Period.Geochronological data show that the meta-mafic rocks have zircon ages of 2 395-2 316 Ma.They have high TiO_2 contents of 1.40 wt.%-3.66 wt.% and Nb concentrations of 13.7 ppm-45.5 ppm,thus aregrouped as Nb-enriched mafic rocks.These mafic rocks are characterized by tholeiitic compositions with enrichment of LREEs and LILEs,and can be divided into two groups.Group 1 samples display E-MORB-like geochemical characteristics.Group 2 samples have positive ENd(t) values of 4.0-5.0.Geochemical data indicate that all meta-mafic rocks were likely derived from a depleted asthenospheric mantle.REE modeling indicates lower degree of partial melting for Group 2 samples(3%-10%) relative to Group 1 samples(15%-20%).Taking into account contemporaneous post-collisional granitoids in southwestern Yangtze Block,we propose that these meta-mafic rocks were formed in a post-collisional extension setting.These meta-mafic rocks can be compared with those in Africa,South America and Europe,and might be linked with the Arrowsmith orogenic belt. | Guichun Liu Xin Qian Jing Li Jian-Wei Zi Tianyu Zhao Qinglai Feng Guangyan Chen Shaobin Hu | 2020 | Journal of Earth Science2020，31，1： | 3 |
| 4 | 湖北宜昌下白垩统五龙组风成砂的发现及其物源分析显示文摘白垩纪时期,我国中纬度地区广泛发育风成砂岩,指示了副热带沙漠带的存在。对白垩纪风成砂岩的发育年代、分布范围、物质来源、所记录的古风向等方面的研究,有助于重建东亚地区白垩纪不同时期的古地理和古气候特征。为此,对湖北宜昌地区下白垩统五龙组(K_(1)w)中发育的一套巨厚的白垩纪砂岩开展了系统的野外沉积特征调查、室内粒度分析、石英颗粒表面微观特征的扫描电镜观察,以及碎屑锆石U-Pb年代学研究,探讨了其成因和物源特征。结果表明:①该套砂岩分布于江汉盆地西缘白垩纪洪积扇的扇缘部位,出露厚度超过40 m,发育大型高角度交错层理,其粒度组成十分均一,其野外特征和粒度组成符合风成沙的特征;②扫描电镜观察显示,石英颗粒普遍磨圆较好,表面发育碟形和新月形撞击坑,以及溶蚀作用和沉淀作用导致的微观特征,与风成砂的特征一致;③该套砂岩的碎屑锆石年龄存在4个主要的峰值,分别约为2.46,1.85 Ga,780,170 Ma,这些年龄峰值与秦岭-大别造山带及黄陵隆起之上沉积盖层的碎屑锆石年龄组成一致,指示其物源可能主要来自黄陵隆起形成后其上覆盖的南华系-侏罗系的侵蚀物,同时可能也混入了部分秦岭-大别造山带的物质;④该套砂岩中最年轻的锆石年龄为(119.9±2.8)Ma,指示该段地层的年龄不早于早白垩世晚期,与湖北省地质调查院将五龙组划归下白垩统一致。上述结果指示着该套砂岩为早白垩世时期干旱气候条件下发育于干旱盆地洪积扇边缘的沙漠沉积,指示着湖北宜昌地区在早白垩世副热高压的影响下已出现了地带性沙漠。 | 王倩 肖国桥 高慧 秦世玉 黄咸雨 | 2023 | 地质科技通报2023，42，5： | 1 |
| 5 | New Research Progress on the Pre-Sinian Tectonic Evolution and Neotectonics of the Huangling Anticline Region,South China显示文摘In this paper the authors briefly introduce and review the new progress of the newly dis- covered Proterozoic Miaowan (庙湾) ophiolite and Neoproterozoic Huangling (黄陵) granitoids in the southern Huangling anticline in the Yangtze craton, and the tectonic evolution significance of assemblage and breakup of Rodinia and Columbia supercontinent in South China. | 彭松柏 Timothy M Kusky 周汉文 王璐 项伟 | 2012 | Journal of Earth Science2012，23，5： | 1 |
| 6 | Depositional age and tectonic environment of the Gouap banded iron formations from the Nyong group,SW Cameroon:Insights from isotopic,geochemical and geochronological studies of drillcore samples显示文摘The discovery of the Gouap banded iron formations(BIFs)-hosted iron mineralization in the northwestern of the Nyong Group(Ntem Complex)in southwestern Cameroon provides unique insights into the geology of this region.In this contribution,we firstly report detailed study of geochemistry,isotopic and geochronology of well preserved samples of the Gouap BIFs collected from diamond drillcores.The Gouap BIFs consist mainly of amphibole BIFs and amphibole-pyrite BIFs characterized by dominant Fe_(2)O_(3)+SiO_(2)contents and variable contents of CaO,MgO and SO_(3),consistent with the presence of amphibole,chlorite,epidote and pyrite,formed during amphibolite facies metamorphism and overprinted hydrothermal event.The amphibole–pyrite BIFs are typically enriched in trace and rare earth elements(REE)compared to the amphibole BIFs,suggesting the influence of detrital materials as well as secondary hydrothermal alteration.The Post Archean Australian Shale(PAAS)-normalized REE–Y profiles of the Gouap BIFs display positive La,Eu anomalies,weak negative Ce anomalies,indicating a mixture of low-temperature hydrothermal fluids and relatively oxic conditions probably under relative shallow seawater.We present here the first isotopic data of BIFs within the Ntem Complex.Theδ^(30)Si_(NBS28)values of the quartz from the Gouap BIFs vary from-1.5‰to-0.3‰and from-0.8‰to-0.9‰for the amphibole BIFs and amphibole–pyrite BIFs,respectively.The quartz hasδ^(18)OV-SMOW values of 6.8‰–9.5‰(amphibole BIFs)and 9.2‰–10.6‰(amphibole–pyrite BIFs).The magnetite from the Gouap BIFs showsδ^(18)O values ranging from-3.5‰to-1.8‰and from-3‰to-1.7‰for the amphibole BIFs and amphibole–pyrite BIFs,respectively.Moreover,the pyrite grains in the amphibole–pyrite BIFs displayδ34S values of 1.1‰–1.8‰.All isotopic data of the Gouap BIFs confirm that they might have precipitated from low-temperature hydrothermal fluids with detrital input distant from the volcanic activity.According to their geochemical and isotopic characteristics,we propose that the Gouap BIFs belong to the Superior type.In situ U–Pb zircon dating of BIFs was conducted to assess the BIF depositional age based on strong evidence of zircon in thin section.The Gouap BIFs were probably deposited at 2422±50 Ma in a region where sediments extended from continental shelf to deep-water environments along craton margins like the Caue Formation of the Minas Supergroup,Brazil.The studied BIFs have experienced regional hydrothermal activity and metamorphism at 2089±8.3 Ma during the Eburnean–Transamazonian orogeny.These findings suggest a physical continuity between the protocratonic masses of both Sao Francisco and Congo continents in the Rhyacian Period. | Landry Soh Tamehe Chongtao Wei Sylvestre Ganno Carlos Alberto Rosiere Jean Paul Nzenti Chesther Gatse Ebotehouna Guanwen Lu | 2021 | Geoscience Frontiers2021，12，2： | 1 |
| 7 | 扬子克拉通核部黄陵基底地质调查新进展显示文摘湖北1∶5万水月寺幅、雾渡河幅区域地质调查工作,在扬子陆核黄陵基底物质组成及其时代调查研究方面取得新进展。变质地层方面,确认野马洞岩组属太古代绿岩带的残留,解体了原元古代黄凉河岩组,定义力耳坪岩组为古元古代蛇绿混杂岩,限定周家河岩组为新太古代;岩石方面,发现古太古代地质实体,识别了新太古代岩浆事件,确认了白竹坪火山岩建造时代为古元古代,重新厘定了南部新元古代岩浆演化序列,总结了区域的构造演化历史。这些成果对于推动黄陵基底乃至扬子克拉通其他前寒武纪结晶基底的地质问题研究具有引导作用。 | 周舟 魏运许 牟宗玉 李方会 段其发 | 2019 | 资源环境与工程2019，33，S01： | 0 |
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