Authigenic sulfide minerals and their sulfur isotopes in sediments of the northern continental slope of the South China Sea and their implications for methane flux and gas hydrate formation

This is a report of the study of the authigenic sulfide minerals and their sulfur isotopes in a sediment core (NH-1) collected on the northern continental slope of the South China Sea, where other geo-physical and geochemical evidence seems to suggest gas hydrate formation in the sediments. The study has led to the findings: (1) the pyrite content in sediments was relatively high and its grain size relatively large compared with that in normal pelagic or hemipelagic sediments; (2) the shallowest depth of the acid volatile sulfide (AVS) content maximum was at 437.5 cm (>2 μmol/g), which was deeper than that of the authigenic pyrite content maximum (at 141.5-380.5 cm); (3) δ 34S of authigenic pyrite was positive (maximum: 15‰) at depth interval of 250-380 cm; (4) the positive δ 34S coincided with pyrite enrichment. Compared with the results obtained from the Black Sea sediments by Jorgen-sen and coworkers, these observations indicated that at the NH-1 site, the depth of the sulfate-methane interface (SMI) would be or once was at about 437.5-547.5 cm and the relatively shallow SMI depth suggested high upward methane fluxes. This was in good agreement with the results obtained from pore water sulfate gradients and core head-space methane concentrations in sediment cores collected in the area. All available evidence suggested that methane gas hydrate formation may exist or may have existed in the underlying sediments.     

砼的施工温度与裂缝之间的关系及其防治

在温度较低、温差较大的地区,砼的施工与施工温度存在着很大的关系。特别是在黑龙江北部地区,在砼施工的过程当中,更要注意砼的施工温度与裂缝之间的关系,做好防治工作。通过多年的现场观察,以及查阅了有关混凝土内部应力方面的专著,对混凝土的施工温度与裂缝产生的原因、现场混凝土温度的控制和预防裂缝的措施有了一定的心得体会和现场施工经验。     

澳大利亚高压对南海夏季风爆发前期的影响

利用NCEP/NCAR的在分析资料,分析了1948～2004年期间澳大利亚（以下简称澳高）的年变化和日变化及其对南海夏季风的影响。结果显示在澳高强弱年这种影响有着不同的结果：在年际变化中,澳高与南海夏季风的相关性在澳高弱年明显大于强澳高年;而日变化中,澳高与南海夏季风的相关性在澳高弱年为正,澳高强年则为负。进一步研究表明,造成这些现象的原因大致可以归为：强弱澳高年,越赤道气流的通道变换;西太平洋副热带高压（以下简称副高）的位置偏向;马斯可林高压（以下简称马高）的作用的叠加效应.这些作用对于南海夏季风的重要组成部分：越赤道气流产生了重要影响,从而影响了南海夏季风的强度。     

混合地震反演技术及其在东海南部陆架盆地中的应用

介绍了一种在无井或少井情况下的叠前叠后混合地震反演方法。该方法充分利用了叠前反演分辨率高和叠后反演效率高、抗噪能力强的优点。首先应用遗传算法理论在所选控制点的角道集数据上进行叠前波形反演,求取控制点的虚拟纵波速度曲线;然后利用纵波速度曲线和已知地质信息来建立初始模型,进行叠后约束反演。我国东海南部陆架盆地勘探程度低、探井数量少,适合于混合地震反演技术的应用。利用该地区的实际资料进行了混合地震反演,并对影响混合地震反演效果的关键因素（层速度、角道集数据、迭代次数、已知地质信息）进行了分析。结果表明,为了获取虚拟纵波速度,需要准确的速度谱和角道集数据;为了增强叠前反演的实用性,需要选择恰当的控制点;充分利用已知地质信息,可以减小叠后反演结果的多解性。     

珍贵濒危动物 白鹮

分布:在东北北部繁殖,广东,福建越冬(国家二级保护动物)大型涉禽。身长约70厘米,全身羽毛白色,头与上颈皮肤裸露,呈黑色,背及颈的下部有灰色饰羽(冬季无)。嘴长而下弯,黑色,脚黑色。栖息于河、湖岸边及沼泽湿地,涉水啄食小鱼等水生动物。繁殖期两性共同在近水岸边的大树上筑巢,每窝产卵2～4枚,淡蓝色,有少许斑点或无斑点。     

越南：争夺南海最嚣张

在与中国存在海上领土争端及海洋划界争端的各周边邻国中，越南是最突出的一个国家，因为它是迄今惟一对南海提出全部主权要求及南海归属所谓历史与法理依据的国家。越南不仅强占我国的岛屿、岛礁最多，攫取的海上资源最多，而且还于2007年在越共全国代表大会上通过了《至2020年越南海洋战略》决议，将海洋发展与海上安全提升至国家战略的层次。2009年5月，越南将南海“划界案”提交到联合国大陆架界限委员会，妄图将已经霸占的我南沙岛屿合法化、永久化、复杂化。     

解决南海问题的几点思考

我们都说南海处于"多事之秋",那么"南中国海之冬"这股寒流从何而来呢?我认为还是美国重返亚太带来的.目前对于美国重返亚太有两种看法:一是认为美国是为了凸显自己在亚太地区的军事存在,并非针对中国.二是认为美国就是为了包围中国、制衡中国.我个人认为,宁可信其有不可信其无.不论美国是否有能力包围中国,其意图肯定是存在的.     

济南北郊稻田土壤动物群落的初步研究

调查研究小清河水对土壤造成污染，从而影响土壤动物群落的区系组成、多样性、均匀及垂直分布。     

Deep sea pollen record during 12－1.6 Ma from the southern South China Sea and its response to envi-ronmental change

Based on deep-sea pollen results (512-76 m) from ODP Site 1143 in the southern South China Sea (SCS),the climate and vegetation evolution sequence on the surrounding islands and the exposed continental shelf are discussed. The pollen records show that the pollen influx was quite low before 8.15 Ma and increased dramatically afterwards. The influx changes can be ascribed,on one side,to tectonics deformations around the southern SCS resulting in rapid uplift of islands and subsequent increase of the sediment rates and pollen influx and on the other side to climate cooling and monsoon enhancement. Around 2.63 Ma was another obvious boundary,the increasing of pollen and spores influx since this time was mainly related to global climate cooling. Spectrum analysis of pollen influx values shows that 2 Ma,0.67 Ma,and 0.19-0.17 Ma cycles existed during 12-3.0 Ma,while 0.1 Ma and 46.9 ka cycles existed during 3.0-2.0 Ma.     

“大自然之手”的作用

在智利北部阿塔卡马沙漠中一片了无生息的遥远角落，散落着一些重达0．5～8吨的大圆石（地质学上称作巨砺）。奇怪的是，虽然阿塔卡马沙漠是地球上最干燥的地方之一，几乎没有雨水来冲刷这些巨石，