武当地区武当岩群变火山岩原岩性质及其构造环境研究

武当岩群中的变火山岩类经历了海水蚀变和区域变质的改造,其岩石学特征和化学成分发生了较大变化。不活动组分的研究表明,武当岩群中的变基性火山岩属拉斑玄武岩浆系列,原岩为玄武岩类;变酸性火山岩属钙碱性岩浆系列,原岩为流纹岩类,后者是前者结晶分异的产物。它们的地球化学特征具岛弧火山岩的性质,形成于岛弧环境。     

雪宝顶绿柱石的谱学研究

本文对雪宝顶绿柱石的晶体化学、矿物谱学、热释光和流体包裹体特征等进行了分析讨论。结果表明,雪宝顶绿柱石化学成分具有富碱、富水、过渡金属离子以Ｆｅ＾３＋、Ｆｅ＾２＋为主的特点。碱金属离子,水和Ｆ＾２＋存在于绿柱石结构隧道中,隧道水分为Ⅰ型和Ⅱ型两类,Ⅰ型水可以进一步区分为Ⅰ１和Ⅰ２两亚类,Ｆｅ＾２＋主要与隧道水结合形成水合离子「Ｆｅ＾２＋（Ｈ２Ｏ）」。Ｆｅ＾３＋主要占位于绿柱石ＡｌＯ６八面体中的Ａｌ     

铁闪锌矿中铁占位的物化条件及机制

对黄沙坪铅锌矿床内带铁门锌矿的研究表明,其形成的温度为300C土;压力大致为107Pa;fs2约为10(12.36);fo2约为10(35.14);pH值约为5．5;pco;约为7．93×104～17．86×104Pa。成矿溶液中Fe和Zn的主要存在形式有：FeCl 、FeOH 、FeCl0、Zn（HS）、ZnCl 、ZnCl以及Fe2 等。铁闪锌矿中Fe2 含量与温度和fs2关系最密切,而后者更为重要。Fe2 是在铁闪锌矿结晶过程中进入八面体位置的一这是ZnS与FeS之间构成有限固港体的根本原因。     

豫南高压麻粒岩中富钛角闪石类的成因和意义

作者用光学方法、电子探针分析方法、红外吸收光和Ｘ射线粉晶衍射方法对豫南高压麻粒岩中的富钛角闪石类进行了详细。结果表明这些富钛角闪石可分别属于钛角闪石类和成分的宇镁绿钙闪石的富钛角闪石类。它们系幔源偏碱生镁铁质岩类成分相当的原岩子高压麻粒岩相变质条件下再平衡后的变质残余矿物和重结晶矿物。     

金矿床的定年方法述评

从金矿床复杂的成矿时代出发,仔细分析当前常用金矿床定年方法,如Ｕ－Ｐｂ法,含金矿物和矿物流体包裹体定年方法,Ｒｅ－Ｏｓ法、裂变径迹法的适用性与局限性,讨论了当今成矿时代研究中存在的问题,并建立了准确的定年步骤。     

唐岛湾清淤工程整体动床物理模型试验研究

针对唐岛湾内清淤工程,开展了唐岛湾整体动床物理模型试验。通过试验资料分析了在SW(西南)向极限波的作用下,波流动力调整以及湾内泥沙冲淤变化。试验表明,当水位高于平均高潮位时,方案一有效波高相对现状平均增大0.3m,方案二有效波高相对现状平均增大0.6m左右;工程区域内各测点的底流速变化基本上都具有周期性和非对称性,变化周期大约为10s,接近SW向入射波的波周期的2倍;方案二的动力环境与冲淤变化程度,好于方案一。试验研究成果可供类似工程应用时参考。     

Prediction of load-displacement performance of grouted anchors in weathered granites using FastICA-MARS as a novel model

With the rising needs of better prediction of the load-displacement performance of grouted anchors in an era of developing large-scale underground infrastructures,the existing methods in literature lack an accurate analytical model for the real-life projects or rigorous understanding of the parameters such as grouting pressures.This paper proposes Fast ICA-MARS as a novel data-driven approach for the prediction of the load-displacement performance of uplift-resisting grouted anchors.The hybrid and data-driven Fast ICA-MARS approach integrates the multivariate adaptive regression splines(MARS)technique with the Fast ICA algorithm which is for Independent Component Analysis(ICA).A database of 4315 observations for 479 different anchors from 7 different projects is established.The database is then used to train,validate and compare the Fast ICA-MARS approach with the classical MARS approach.The developed Fast ICA-MARS model can provide more accurate predictions than MARS.Moreover,the developed Fast ICA-MARS model is easy to interpret since the evaluation of the parameter importance of the independent components can be conducted along with the considerations of the correlations with the original variables.It is noteworthy to point out that the grouting pressures play a central role in the proposed model,which is considered of paramount importance in engineering practices but has not been properly taken into account in any prior analytical or empirical predictive models for the load-displacement relationships.     

突泉县生态环境与气候变化

通过对突泉县近50a来气候变化对农牧业的影响,阐述了气候变暖对突泉县生态环境的影响,提出了生态环境防治对策。     

Material records for Mesozoic destruction of the North China Craton by subduction of the Paleo-Pacific slab

It is well known that the destruction of the North China Carton(NCC) is closely related to subduction of the PaleoPacific slab, but materials recording such subduction has not been identified at the peak time of decratonization. This paper presents data of whole-rock major and trace elements and Sr-Nd-Hf isotopes and zircon U-Pb ages and Hf-O isotopes for Mesozoic volcanic rocks from the Liaodong-Jinan region in the northeastern NCC, in order to trace the subduction-related materials in their source and origin. The Mesozoic volcanic rocks in the Liaodong-Jinan region are mainly composed of two series of rocks, including alkaline basaltic trachyandesite, trachyandesite and trachyte, and subalkaline trachyandesite and andesite. Zircon U-Pb dating yields eruption ages of 129–124 Ma for these rocks. The Early Cretaceous volcanic rocks are all enriched in LILEs(such as Rb, Sr, Ba and Th) and LREEs, depleted in HFSEs(such as Nb, Ta and Ti), indicating that they were originated from mantle sources that had been modified by subducted crustal materials. However, they have relatively heterogeneous and variable isotopic compositions. The alkaline basaltic trachyandesite, trachyandesite and trachyte have enriched whole-rock Sr-Nd-Hf and zircon Hf isotopic compositions and mantle-like δ~(18)O values, suggesting that they were derived from low-degree partial melting of an isotopically enriched lithospheric mantle source. In contrast, the subalkaline trachyandesite and andesite have relatively depleted isotopic compositions with zircon ε_(Hf)(t) values up to +5.2 and heavy zircon O isotopic compositions with δ~(18)O values of +8.1‰ to +9.0‰, indicating that they were originated from a lithospheric mantle source that had been metasomatized by melts/fluids derived from the recycled low-T altered oceanic basalt. All of these geochemical features suggest that the Early Cretaceous volcanic rocks in the Liaodong-Jinan region would result from mixing of mafic magmas with different compositions. Such magmas were originated from the enriched lithospheric mantle and the young metasomatized mantle, respectively, with variable extents of enrichment and depletion in trace elements, radiogenic isotopes and O isotopes. Importantly, the identification of the low-T altered oceanic crust component in the origin of Early Cretaceous volcanic rocks by the zircon Hf-O isotopes provides affirmative isotopic evidence and direct material records for Mesozoic subduction of the Paleo-Pacific slab that induced decratonization of the North China Craton.     

Eco-districts in France: What tools to ensure goals achievement?

Globally, to build cities and communities more inclusive, safe, resilient and sustainable is one of the most important sustainable development goals. Eco-districts in cities emerged as an answer to current global environmental concerns and have been developed in France since the 1990s. The objective of this work is to gather operational feedback from sustainable neighborhood projects owners to better understand the key barriers of such projects and how to overcome them. A case study of the eco-district Les Tanneries, Lingolsheim showed that the carbon footprint of each inhabitant annually amounted to 4 tons CO_2 equivalent, more than half of the French average. Rooms for improvements were clearly identified regarding transports and food carbon footprint. Indicators for energy consumption, social diversity and density reached the level of the eco-districts average. A governance review pointed out some superior practices such as the formalization of a specification requirements handbook, a competition between project management teams, and the use of neighborhood sustainability assessment tools to measure and track changes in performance. The validated tools and obtained results can be useful in building sustainable cities and even China's ecological civilization.