滇西北普朗斑岩铜矿床成矿时代及其意义

普朗斑岩铜矿在中国斑岩铜矿床中有其特殊性,无论对中甸岛弧带的基础地质还是矿产资源评价预测的研究,都具有重要意义。然而,该斑岩铜矿床无确切的年代学数据。通过作辉钼矿Re-Os年龄和单矿物K-Ar年龄测定,首次确定了普朗斑岩铜矿床内具有钾硅酸盐化的黑云石英二长斑岩成矿作用的活动时间为(235.4±2.4)Ma～(221.5±2.0)Ma,石英-辉钼矿阶段的辉钼矿Re-Os年龄大致为(213±3.8)Ma,两者十分相近。表明普朗斑岩铜矿床的成矿作用是在印支期完成的。主矿体钾长石K-Ar年龄显示热液活动持续到(182.5±1.8)Ma左右,说明与斑岩铜矿有关的热液系统寿命可达40Ma之久。这种长寿命的热液系统是高品位大规模的斑岩铜矿形成的必要条件之一。     

Structure and evolution of the Glueckstadt Graben due to salt movements

The salt tectonics of the Glueckstadt Graben has been investigated in relation to major tectonic events within the basin. The lithologic features of salt sections from Rotliegend, Zechstein and Keuper show that almost pure salt is prominent in the Zechstein, dominating diapiric movements that have influenced the regional evolution of the Glueckstadt Graben. Three main phases of growth of the salt structures have been identified from the analysis of the seismic pattern. The strongest salt movements occurred at the beginning of the Keuper when the area was affected by extension. This activation of salt tectonics was followed by a Jurassic extensional event in the Pompeckj Block and Lower Saxony Basin and possibly in the Glueckstadt Graben. The Paleogene–Neogene tectonic event caused significant growth and amplification of the salt structures mainly at the margins of the basin. This event was extensional with a possible horizontal component of the tectonic movements. 3D modelling shows that the distribution of the initial thickness of the Permian salt controls the structural style of the basin, regionally. Where salt was thick, salt diapirs and walls formed and where salt was relatively thin, simple salt pillows and shallow anticlines developed.     

东天山觉罗塔格红云滩花岗岩年代学、地球化学及其构造意义

东天山觉罗塔格地区广泛发育的晚古生代岩浆岩及相关的矿产一直是东天山大地构造研究的焦点。觉罗塔格南缘红云滩花岗质岩体的岩石、矿物组合显示典型的钙碱性火山弧花岗岩特征。岩石地球化学研究表明,该花岗质岩石富集大离子亲石元素而亏损高场强元素,是洋壳俯冲所导致的下地壳物质部分熔融、岩浆分离结晶和上地壳同化混染作用的产物。LAM-ICP/MS锆石定年结果表明,红云滩花岗岩侵位于早-中石炭世(328．5±9．3Ma)。结合觉罗塔格地区由南至北,晚古生代矿产分布由火山沉积-热液改造型铁矿向斑岩型铜钼矿过渡的特征、火山-沉积岩分布和该区晚古生代的大地构造演化历史,作者推测:早古生代觉罗塔格洋向塔里木板块俯冲并形成中天山岛弧之后,该洋盆并未完全消亡,并于晚古生代时极性反转,向北俯冲于准-吐-哈地块之下。红云滩花岗岩正是形成于晚古生代觉罗塔格俯冲洋壳之上的火山弧环境。觉罗塔格地区晚古生代的岩浆岩,火山-沉积岩和矿产分布均不同程度受控于这一大地构造背景。     

Evolution of the Bayramiç magmatic complex, northwestern Anatolia

During the Oligocene–Middle Miocene period widespread magmatic activity developed in Western Anatolia, following the continental collision between the Sakarya continent and the Tauride–Anatolide platform. This produced both intrusive and extrusive rocks, which appear to be associated in space and time, as exemplified from the Bayramiç area. In the Bayramiç area, the magmatic activity started with the intrusion of the Evciler granite, and the coeval lower volcanic association. This was followed by the development of the upper volcanic association. These rock groups form collectively the Bayramiç magmatic complex, which was generated under an on-going north–south compressional regime. The Bayramiç magmatic complex has a subalkaline composition, displaying a calcalkaline trend. Trace elements and REE contents resemble to island-arc and collision-related magmas. According to the isotope values the Bayramiç magmatic complex was derived from the magmas of lithospheric mantle origin, which were later contaminated, while passing through the thick continental crust, in a post-collisional tectonic setting, during the Oligocene–Early Miocene period. The latest product of the magmatism is the Late Miocene–Pliocene basalt lavas. Their geochemical properties are clearly different from the Oligocene–Early Miocene magmatic rocks. The basalts were generated when the north–south compression gave way to the north–south extensional regime.     

吉林省夹皮沟金矿成因研究

吉林省夹皮沟金矿区金矿赋存在夹皮沟北西向韧性带内,控矿构造为叠加在韧性剪切带之上的脆性构造。中生代中酸性脉岩为成矿期脉岩,且与黄泥河花岗岩岩基有着密切的成因联系。成矿物质主要来自岩浆分异,金丰度值高的暗色岩类提供部分矿质。     

浙西北二叠,三叠纪浊积岩系及其大地构造意义

对浙西北上二叠统长兴组，大隆组及下三叠统政棠组沉积特征，生物生态等的研究表明，长兴组，大隆组和政棠组为一套浊积岩系沉积，沉积背影为一向东南倾斜的被动大陆边缘，印支期造山作用使其发生了强烈的前陆褶皱－冲断变形，岩石地球化学分析结果表明在浊积岩沉积时期，推测可能存在的部分来来源于晚元古代岛弧和晚元古代造山带的物源。     

夏季西北干旱区干,湿年环流及高原动力影响差异的对比分析

为了更深入地分析西北干旱气候形成的原因，并研究各影响因子之间的联系，利用１９７９－１９８６年夏季（６－８月）的ＥＣＭＷＦ的格点资料和我们先前划分的夏季高原北侧地区干，湿等级资料，进一步作了夏了高原北侧地区干，湿间平均环流和高原动力等因子差异的对比分析，讨论了这些差异对该地区干。湿年形成的贡献，结果指出，由于青藏高原及深居内陆环境造成了西北干旱背景。而高原的热力，动力作用，环流特征等各因子逐年之间的     

西北太平洋强地震的节律性与El Nino和地球自转

本文利用100年来西北太平洋强地震资料分析发现:强震有明显的“活跃期”与“平静期”交替的现象。“强震活跃”与“E1 Nino事件”两者的同时相关系数达0.62,信度高于0.1％。“强震活跃”与地球自转减慢亦有很好的同步性。文中还对这三种重要的地球物理现象基本同步的原因进行了讨论,认为可能是叠加在太平洋地幔对流圈上的“正扰动”所同时产生的三个结果。     

Seed-like hydroptilid larval cases (Insecta: Trichoptera) from Holocene freshwater deposits

The seed-like larval cases of hydroptilid caddis flies may be mistaken for plant remains in subfossil studies. However, being correctly identified, they may be important for the interpretation of former freshwater environments. Two such subfossil caddis fly remains from Holocene lake sediments and river deposits are described morphologically and their palaeoecological significance interpreted.     

Organic matter characterisation and turnover in the sediment and seawater of a tourist harbour

A survey of a Ligurian tourist harbour was carried out during winter 2006 and summer 2007 in order to study the organic matter (OM) turnover through extracellular enzymatic activity. Seawater and sediments were sampled at six stations, three inside the port boundaries, one outside the port and two in an area influenced by the outflow of a minor river (Boate). The seawater showed OM turnover times similar to other oligo-mesotrophic coastal areas, and low concentrations of chlorophyll-a and inorganic nutrients. The sediments, instead, revealed high OM loads and a predominance of proteolysis. A significant reduction of the OM loads was observed in the outside station, indicating that the OM accumulation was due to the structures and activities of the harbour and to the Boate influence. The OM biotic recycling via enzymatic activity was enhanced especially during summer. Although the carbohydrates were probably highly refractory, their turnover was notably faster, due to glycolytic enzymatic activity that was enhanced more than the proteolytic in both the sediment and in the seawater. This suggested that the removal and recycling of OM were potentially efficient, and prevented the shift to eutrophication of the Rapallo harbour area.