藏南江孜县床得剖面侏罗-白垩纪地层层序及地层划分

重测西藏南部江孜床得剖面后发现地层层序与前人认识完全相反,不只含上白垩统,还包括中—上侏罗统和整个白垩系;重新厘定了宗卓组、加不拉组,新建床得组,它们分属晚坎潘期—马斯特里赫特期、贝里阿斯期—三冬期和早—中坎潘期;由下向上可识别出６套沉积组合：安山岩层、黄层、黑层、白层、红层及滑塌层,大致对应于下热组（Ｊ２ｘ ）、维美组（Ｊ３ｗ ）、加不拉组（Ｋ（１－ ２）ｊ,床得浦段＋ 机布里段）、床得组（Ｋ２ｃ）、宗卓组（Ｋ２ｚｎ）     

DISCOVERY OF THE LATEST MARINE NON-CARBONATE SEDIMENT WESTERN TINGRI, SOUTHERN TIBET

DISCOVERY OF THE LATEST MARINE NON-CARBONATE SEDIMENT WESTERN TINGRI, SOUTHERN TIBET     

Comparing the Upper Triassic Deep-sea Flysch of theShannan Terrane with the Coeval Shallow Shelf Sediments ofthe Tethys Himalaya,Southern Tibet

The provenance and paleogeography of the Upper Triassic deep-sea flysch Langjiexue Group(LG) of the Shannan Terrane in the northeastern Himalaya orogen, south of Yarlung Zangbo, have been disputed in recent years since its affinity to the Tethys Himalaya was suspected during the early 2000 s. Based on the earlier discoveries of the Upper Permian–Triassic basalts and mafic dykes from the LG and of coeval detrital zircons from the Qulonggongba Formation(QF) in shallow shelf sediments of the Tethys Himalaya, the previous viewpoints on the basin and tectonics of the LG have been recently rejected. We compared the two units of the Upper Triassic, and our results reveal a number of differences,discrepancies, and inconsistencies in the debate, raising crucial questions on the postulation and provenance model of the remote Gondwanide Orogen for the LG. It is suggested that more observations and evidence are needed to further improve the paleogeographic understanding and relationship of the two units.     

CMIP6情景中主要温室气体和气溶胶排放强度的时空分布特征分析

基于不同共享社会经济路径（Shared Socioeconomic Pathways, SSPs）形成的8组最新的未来可能情景（SSPx-y情景）,被用于第六次耦合模式比较计划（CMIP6）,以据此来预估未来气候变化的可能幅度和趋势。本文主要对比分析了8组SSPx-y新情景中主要温室气体和气溶胶排放数据的基准年排放强度分布、未来排放强度的时空变化、以及在6个典型区域排放强度的逐年变化等特征。结果表明:二氧化碳（CO₂）、甲烷（CH₄）、黑碳（BC）、二氧化硫（SO₂）在基准年的排放强度高值区都位于东亚和南亚。相比于基准年,2100年CO₂和CH₄在高和低辐射强迫情景下表现出的排放强度变化有显著差异。此外,所有情景下2100年的BC和SO₂全球平均排放强度都弱于基准年的排放强度。在时间变化上,随着生物质能碳捕获与封存技术的不断进步,所有地区在4组不超过3.4 W/m2的低辐射强迫情景下,CO₂排放强度到2100年都呈现负值。其中,南美洲的负排放最强,2100年在SSP5-3.4情景下该地区的排放强度为－0.3 kg m－2 a－1。最后,对比东亚和南亚排放强度的逐年变化可以发现,在各情景所描述的未来发展过程中,东亚的减排行动的成效都要好于南亚。     

雅鲁藏布江蛇绿岩再研究:从地质调查到矿物记录

蛇绿岩带出现于全球大多数碰撞构造带上,通常是板块缝合带的标志,西藏雅鲁藏布江缝合带蛇绿岩带对于此种概念模型是毫无争议的。根据近年来现代洋壳和蛇绿岩研究成果以及分析技术,在20世纪80年代中法合作项目研究成果基础上,笔者再次对西起日喀则拉孜、东至泽当金鲁,长约500km的雅鲁藏布江缝合带蛇绿岩进行了研究。在野外调查基础上,对雅鲁藏布江蛇绿岩中500多个尖晶石样品的地球化学特征进行了分析研究,以探讨蛇绿岩的成因及其动力学背景,提出雅鲁藏布江蛇绿岩带属于超俯冲作用(suprasubduction)的产物,与近年来其他研究成果的认识一致。     

登封2007年春季大到暴雨的特征分析

利用NCEP提供的再分析资料(Global Final Analyses),对2007年3月3日登封市大到暴雨天气过程从动力和热力条件、水汽输送、湿Q矢量等方面进行分析,结果表明:这次降水过程的两个主要降水时段都出现在次级环流的垂直运动上升区内;暴雨过程中登封上空中低层维持一高能区;温度平流值陡降,导致这次降水过程结束和强降温天气的发生;整个暴雨过程登封维持着通畅的水汽通道和较强的水汽辐合,水汽辐合中心区对应降水集中时段.     

Cretaceous Oceanic Redbeds: Implications for Paleoclimatologyand Paleoceanography

The Cretaceous is among the most unusual eras in the geological past. Geoscience communities have been having great concerns with geological phenomena within this period, for example carbonate platforms and black shales in the Early and Middle Cretaceous respectively, during the last decades. But few people have paid any attention to the set of pelagic redbeds lying on the black shales, not to mention the applications to paleoclimatology and paleoceanography. It is shown by the sedimentary records of redbeds, that they were deposited around the CCD, with both a higher content of iron and much lower concentrations of organic carbon, which implies conditions with a     

库姆塔格沙漠研究：进展与成果

库姆塔格沙漠,地跨新疆、甘肃2省区;东起敦煌鸣沙山、西临罗布泊、南依阿尔金山、北抵阿奇克谷地;面积超过2万km^2。境内气候极端干旱,地貌类型复杂、沙丘类型多样,是＂羽毛状沙丘＂在我国的唯一分布区。受自然条件和技术装备等制约,一直是我国八大沙漠中综合科考的最后空白。2006年,＂库姆塔格沙漠综合科学考察＂被列为首批国家科技基础性工作专项重点项目,历时4年,取得了丰硕成果,填补了多项沙漠科考和研究空白。主要包括：（1）首次发现、命名并定义了＂沙砾碛＂这一库姆塔格独特的地貌类型;初步探明了该沙漠独有的＂羽毛状＂沙丘的形态学特征及形成过程;（2）基本探明了库姆塔格沙漠地表沉积物的矿物组成及2个主要物源端元,揭示了晚新生代沉积物特征和地层序列;（3）初步确定了库姆塔格沙漠地区古风成砂的形成时代,并阐明了该沙漠的成因和演化过程;（4）初步查清了库姆塔格沙漠地区现代水系分布及水文特征,绘制完成中更新世晚期、汉、唐、清、民国、现代6个时期的水系演变图;（5）首次确认了库姆塔格沙漠土壤类型及其发育过程和区域分布特征;（6）首次建立了全方位、全天候、全覆盖的库姆塔格沙漠气象观测场,实现了基于卫星传输的气象数据实时采集,初步摸清了羽毛状沙丘形成的动力条件及周边气候演变趋势;（7）基本查清了库姆塔格沙漠野生动植物种群、数量和分布区域,特别是发现了沙生柽柳、白花柽柳、侧花沙蓬等6种植物的分布新区;（8）系统调查了国家一级保护动物双峰野骆驼种群及其生境,对野骆驼的行为生态学进行定位观测研究;（9）完成了沙漠及其周边地区的生态经济功能分区,提出了＂大敦煌＂区域可持续发展的战略对策,为拯救敦煌绿洲、保护敦煌文化遗产提供了重要科学依据。     

仲巴微地体之定义及构成

根据1∶5万西藏仲巴地区区域地质调查工作,结合1∶25万区域地质资料和前人研究成果,对被认为属于雅鲁藏布江缝合带西段夹持于两套混杂岩之间呈狭长分布的海相古生界为主地质体进行了研究。建议统一使用"仲巴微地体"术语以体现其构造属性,并初步定义为:仲巴微地体是指南东起于萨嘎县北查藏一带向北西到中印边界附近、被札达—仲巴—查藏和穷果—门士两条主断裂限制、一套以海相地层为主的地质体,它是由海相(震旦系/)奥陶系—三叠系组成的地层地体。进一步对比研究提出,仲巴微地体大致以巴噶—马攸木为界可分为幕霞和霍尔巴—仲巴两个地层分区,前者岩性未变质—弱变质,地层单斜、褶皱开缓;后者前石炭系以中低级绿岩相—片岩相为主,发育紧闭和同斜倒转褶皱;该地体可以划分为震旦系—寒武系、奥陶系—泥盆系、石炭系—二叠系、三叠系四个构造层,大致反映了其构造和沉积演化。     

Antioxidation and ATPase activity in the gill of mud crab Scylla serrata under cold stress

Mud crab (Scylla serrata) is an important commercial crustacean in China. An experiment was designed to study the effect of cold stress on S. serrata. After a one-week adaptation at 28oC, the temperature is suddenly reduced to 4oC. The crabs were sampled every 2 h for 10 h and dissected immediately to measure the enzyme activity. The crabs at room temperature (28oC) were used as the control group. The activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), the content of malondialdehyde (MDA) and the activity of 4 ATPases (Na , K -ATPase; Mg2 -ATPase; Ca2 -ATPase; Ca2 , Mg2 -ATPase) were measured biochemically. In contrast to the control group, the SOD activity increased significantly from 2 to 6 h after the cold stress, and then decreased. The CAT and GPX activities increased in 2 h, and then decreased gradually. The content of MDA increased gradually in 4 h. The activity of Na , K -ATPase decreased in 2 h, increased up to the top value at Hour 6, then decreased again. The activities of Mg2 -ATPase, Ca2 -ATPase and Ca2 , Mg2 -ATPase increased significantly in 6 h, insignificantly in any other hours. Under cold stress, the activity of antioxidative enzymes in S. serrata was reduced at first then stabilized, ROS-scavenging weakened, and MDA accumulated gradually in the gill after 6 h. The activity of the 4 ATPases in the crab decreased after 6 h, suggesting that the ability to regulate ion concentration has been paralyzed. Therefore, the maximum period to sustain healthy meat in the crab under cold stress is 6 hours.