青海牛苦头矿区两期岩浆岩及其矽卡岩型成矿作用

牛苦头矿床位于东昆仑造山带祁漫塔格地区中段,目前已探明Pb+Zn资源量116万吨(推断及以上),为祁漫塔格地区探明的最大矽卡岩型铅锌矿床之一.M1、M4以及M2三个磁异常区(矿段)为牛苦头矿区主要的矿段(点),矿区发育大量与铅锌多金属矿成矿密切相关的花岗质岩体.本文通过对M1、M4以及M2三个矿段典型矿床地质特征、蚀变...     

太行山南段中生代侵入体微量元素地球化学及岩浆源区性质探讨

本文对在行山南中生代侵入岩体微量元素地球化学进行了系统研究,成果表明各类侵入岩的稀土配分模式均呈轻稀土富重稀土与亏损,且没有铕异常,认为这是由于岩石中副矿物中的负铕异常与主要矿物长石类矿物中高的正铕异常低消的结果,本文还探讨了岩浆源区的特点,认为为本区岩石多具幔壳混合来源（ＭＣ型）部分来自幔源（ＭＣ型）。     

The European research project on reed die-back and progression (EUREED)

Reeds (Phragmites australis (Cav.) Trin. ex Steudel) are dying back at a fast rate in sizeable areas of Europe, with significant impacts on important wetland functions (biodiversity, stability of river and lake margins, water quality) and local economy. EUREED is a European strategic fundamental research initiative that aims at analyzing the mechanisms which control the growth dynamics and stability of reed-dominated ecosystems, at modelling and predicting how the ecosystem is disturbed by human activities and climate change, and at developing remedial management options. Expected achievements include (i) assessment of the functional role of reed-dominated ecotones as nutrient accumulators and transformers and as sources for atmospheric greenhouse gases, (ii) an ecosystem model capable of predicting future changes in ecosystem functioning in relation to climatic conditions, trophic status and water table management, (iii) assessment of genetic diversity of reed populations and its relation to die-back, and (iv) development of management tools, including preventative and restorative measures in relation to die-back. The project is carried out by research groups with complimentary skills and expertise from nine European countries. A reference study site is selected in each country as the basis for the field studies. The reference sites cover boreal-mediterranean and oceanic-continental climatic gradients, and the observational and experimental studies at these sites will permit interpolation between sites and extrapolation of results to the European scale.     

渤海湾盆地第三纪的岩浆旋回

本文提出了岩浆旋回的概念,初步探索了岩浆旋回的划分方法,并以构造演化为基础,结合岩浆活动方式、岩石地球化学指标,对渤海湾盆地岩浆旋回进行了划分。盆地中第三纪岩浆活动划分为两大旋回：早第三纪华北Ⅰ幕旋回和晚第三纪华北Ⅱ幕旋回。第一旋回（华北Ⅰ幕）划分为3期：孔店组（房身泡组）—沙河街组四段期、沙河街组三段—沙河街组二段期及沙河街组一段—东营组期。第二旋回（华北Ⅱ幕）为晚第三纪。旋回内部各期的早、晚岩浆活动形式有所不同。     

孟加拉湾晚第四纪冰期和间冰期古生产力演变研究

近赤道低纬度地区孟加拉湾属于大陆边缘深海环境,该区的古生产力研究对于了解低纬度地区古气候演变及其对全球气候变化的响应具有重要意义。通过对研究区４个活塞岩心δ１３Ｃ值、高生产力指示种的含量变化、浮游有孔虫与底栖有孔虫丰度、Ｕ＋Ｂ指数等方面的研究发现,研究区受冰川－气候旋回作用影响明显,古生产力波动强烈。冰期时,陆源营养物质供应充分导致生物生产力增大,因而末次冰期最盛期氧同位素第２期时生产力最高,间冰期氧同位素第１、５期时生产力较低。该区氧同位素第３期也出现高生产力的情况,可能与当时研究区气候不稳定有关。氧同位素第３期强烈的西南季风活动使研究区淡水输入增强,进一步增加了冷、暖期生物生产力的差异。     

浙西中生代岩浆岩特征及其与铀矿的关系

本文综合了浙西铀成矿区中生代燕山期中酸性火山岩、次火山岩及基性侵入岩在成岩时间、岩石系列、成岩顺序、岩石成分、控岩因素、成岩环境等方面的特征 ,表明它们分别为壳、幔不同源区的产物。根据不同类型铀矿床与上述岩浆岩的时空关系 ,认为早期 (早白垩世 )铀 赤铁矿型矿石为壳源酸性火山岩浆作用的产物 ,而晚期 (晚白垩世 )沥青铀矿 多金属硫化物、沥青铀矿 紫色萤石型富铀矿石为幔源基性岩浆作用的产物。进而 ,笔者提出了这两种类型铀矿的找矿标志。     

旋回地层──一个正在发展中的理论

地层中的旋回性很早就引起了人们的注意。Ｍ． Ｍｉｌａｎｋｏｖｉｔｃｈ对地球轨道参数的定量计算和对冰期的解释是旋回地层发展的重要里程碑。６０～７０年代开展的ＤＳＤＰ项目,在深海沉积记录中发现了支持米兰科维奇理论的强有力证据,使该理论得以复活。８０年代,层序地层的发展和全球地质观的兴起又重新激发了人们对地层旋回性研究的热情,并形成了一个新的地质学分支──旋回地层学。     

MAGMATIC ACTIVITY RELATED TO LATE PALEOZOIC RIFTING IN CENTRAL QIANGTANG PLATEAU

MAGMATIC ACTIVITY RELATED TO LATE PALEOZOIC RIFTING IN CENTRAL QIANGTANG PLATEAU     

Relations between A-type granites and copper mineralization as exemplified by the Machangqing Cu deposit

This paper deals with the relations between the Machangqing rockbody which corresponds to the A-type granites and porphyry copper mineralization in terms of petrochemistry, trace element geochemistry, fluid inclusion geochemistry and isotope geochemistry. The results show that the Machangqing porphyry copper deposit was formed from the fluid predominated by mag-matic fluid. This kind of ore-forming fluid was just differentiated from the magma responsible for the A-type granites. Therefore, as viewed from whether they contain water or not, the A-type granites can, at least, be divided into two types: water-bearing and water-free. The water-bearing A-type granites can serve as the host of porphyry copper deposits under certain geological conditions.