Phytoplankton pigment patterns and community composition in the northern South China Sea during winter     

翟红昌  宁修仁  唐学玺  郝锵  乐凤凤  乔静 《中国海洋湖沼学报》2011,29(2)

Phytoplankton pigment patterns and community composition were investigated in the northern South China Sea using high-performance liquid chromatography and the CHEMTAX software from February 11 to 23, 2009. We recognized four different vertical distribution patterns of pigments: chlorophyll a (Chl a)-like type, divinyl chlorophyll a (DV Chl a) type, even distribution type, and surface type. The average value of ratios of accessory photo-protective pigments (APP) to accessory photo-synthetic pigments was 0.8...  相似文献   

Analysis on Buckling Performance of Submarine Pipelines During Deepwater Pipe-Laying Operation     

袁林  龚顺风  金伟良  李志刚  赵冬岩 《中国海洋工程》2009,23(2):303-316

Pipes inevitably encounter high ambient pressure and bending moment during the deepwater pipe-laying process,which can lead to elliptical buckling and even deterioration failure.For the safety of pipe-laying operation,available formalas for the pipe stability are established on the basis of the assumption of uniform deformation along the tube length and symmetrical buckling.This method can predict the nonlinear rcsponse of elliptical collapse of steel circular tubes for different ratios of diameter to thickness (D/t) under pure bending or combined bending and external pressure.In these formulas,the strain-displacement relationship is deduced from the nonlinear ring theory,and the Ramberg-Osgood constitutive model is applied to simulate the inelastic material behavior.Meanwhile,the principle of virtual work is adopted to derive the equilibrium equations.A set of equations is solved by the Newton-Raphson method,and the iterative scheme contains nested iteration for the constitutive relation.In order to check the effectiveness of this theoretical method,illustrative examples are presented in this paper.Besides,the numerical simulation is carried out by use of ANSYS.A comparison of the results shows that the theoretical method can provide reasonable prediction for engineering practice.  相似文献   

雅克拉凝析油气田油水界面甲烷天然释放及其源示踪     

唐俊红  鲍征宇  向武 《地球科学》2009,34(5):769-777

为评价油气田天然释放CH₄对大气CH₄源与汇的贡献, 采用静态箱法实地监测了新疆塔里木盆地雅克拉凝析油气田油水界面处甲烷的释放通量, 并采用在线大气甲烷碳同位素制样系统与稳定同位素质谱仪联机测试了通量箱甲烷碳同位素组成.结果表明, 由于油水界面边水活跃程度不同, 甲烷通量在空间变化很大, 最高的日释放通量达2.28 mg/m2·d, 最低-1.32 mg/m2·d, 日平均释放通量0.51 mg/m2·d, 标准偏差达1.23 mg/m2·d.油水界面处甲烷通量日变化规律基本相同, 凌晨至清晨时达到相对高点, 随后逐渐降低, 下午至傍晚时段为释放低值甚至负值, 夜晚时分又逐渐增加.通量箱中甲烷δ13C组成白天随甲烷浓度的线性降低而逐渐偏重, 夜晚δ13C随着甲烷浓度的线性增加而逐渐偏重.可见, 油水界面边水活跃, 其上方的土壤形成相对氧化的环境, 油气藏甲烷及烃类在向地表运移的过程中不断被土壤吸收氧化, 仅有少量运移至地表并逸散到大气中, 局部甚至均被吸收氧化, 而成为大气甲烷的汇.   相似文献   

New Nodosaurid Dinosaur from the Late Cretaceous of Lishui, Zhejiang Province, China   总被引：6，自引：0，他引：6       下载免费PDF全文

LU Junchang JIN Xingsheng SHENG Yiming LI Yihong WANG Guoping Yoichi AZUMA 《《地质学报》英文版》2007,81(3):344-350

A new genus and species of nodosaurid dinosaur： Zhejiangosaurus lishuiensis gen. et sp. nov. is erected herein. It is characterized by the sacrum consisting of at least three true sacral vertebrae, 5 caudal dorsal vertebrae fused to form the presacral rod, wide divergence of long slender preacetabular process of the ilium from the middle line of the body, and the fourth trochanter located at the femoral mid-length.  相似文献   

浙江桐庐阳新统栖霞组的■类化石及多重地层划分     

YAN Tie-zeng  ZHU Chao-hui  LU Cheng-zhong  and XU Xing-miaoZhejiang Geological Survey  Hangzhou 《地层学杂志》2007,(1)

浙江桐庐栖霞组可划分为二个带:上部为Cancelli naneoschwagerinoides-Verbeekina grabaui带,归属祥播阶;下部为Misellinaclaudiae带,归属罗甸阶。栖霞组被划分出3个正层序和6个四级层序。高频旋回层研究表明:栖霞组主要的成岩环境有台地相、浅海陆棚相和盆地相三种类型,从下至上总体反映为台地向盆地的演化环境。  相似文献   

The　application　of　ultrasonic　seismic　model　experiment　in　quality　test　of　cement　mortar　injection　of　Yongjiang　river　submarine　tun－nel　tube　foundation     

杨钢宇  郭铁栓  李金龙  杨导声 《地震学报(英文版)》1996,9(4):665-670

ＴｈｅａｐｐｌｉｃａｔｉｏｎｏｆｕｌｔｒａｓｏｎｉｃｓｅｉｓｍｉｃｍｏｄｅｌｅｘｐｅｒｉｍｅｎｔｉｎｑｕａｌｉｔｙｔｅｓｔｏｆｃｅｍｅｎｔｍｏｒｔａｒｉｎｊｅｃｔｉｏｎｏｆＹｏｎｇｊｉａｎｇｒｉｖｅｒｓｕｂｍａｒｉｎｅｔｕｎ┐ｎｅｌｔｕｂｅｆｏｕｎｄ...  相似文献   

中国南方海相油气勘探研究新进展   总被引：9，自引：2，他引：9  

Petroleum Exploration Project Management of South China  CNPC  Hangzhou Institute of Petroleum Geology  CNPC - Xixi Rd.  Hangzhou  P.R.China 《海相油气地质》1997,2(2):1-15

中国南方海相油气勘探研究取得６个方面的进展；１．重塑了华南板块的四个构造演化阶段，将华南板块划分出三个构造区，一个火山岩区和两个造山带，并了南方构造格架与演化对油气地质条件的控制．２．分析了华南板块南北两个大陆边缘沉积盆地的二级超旋回层序，凝缩层段及其与烃源岩发育的关系，并重点分析了区域性四套主力烃源岩的特点；３．提出了华南板块北南两个前陆盆地带的发育对中国南方海相油气的后期保存起着重要的作用。  相似文献   

塔里木盆地古生界砂岩热成熟度与有效储层的预测   总被引：1，自引：0，他引：1  

寿建峰  朱国华 《海相油气地质》1997,2(3):22-25

根据砂岩热成熟的概念，认为塔里木盆地古生界砂岩的孔隙度主要受控于与地热场、埋藏时间和盆地沉降有关的砂岩热成熟度。用热成熟度比用深度可更合理地解释砂岩孔隙度的发育特征及其成因。ＴＴＩ值可综合反映热成熟程度，ＴＴＩ值越大，砂岩的热成熟度越高，成岩强度越大，被保存的孔隙度越小。若已知盆地的地温梯度，可计算出预测储层的ＴＴＩ值，并可用本文提出的砂岩热成熟度－－孔隙度和热成熟度－－深度的两个定量关系预测砂岩  相似文献   

楚雄盆地含油气系统分析及勘探目标选择   总被引：6，自引：2，他引：4  

梁兴 《海相油气地质》1998,3(2):35-46

楚雄盆地是在扬子板块西南大陆边缘上发育起来的晚三叠世－早白垩世前陆盆地与晚白垩世－第三纪陆内湖盆叠置的构造－沉积残留盆地。  相似文献   

EFFECT OF THE NONLINEAR TERM ON MOVEMENT AND DEVELOPMENT OF TROPICAL CYCLONE   总被引：2，自引：0，他引：2  

田永祥  钮学新 《Acta Meteorologica Sinica》1998,(2)

The dynamics of tropical cyclone is investigated in a nondivergent barotropic model with nobasic flow. The effect of nonlinear term on the movement and development of tropical cyclone isemphatically demonstrated. The advection of asymmetric vorticity by the symmetric flow (AAVS)produces the small-scale gyres (SSGs). The SSGs counterclockwise rotate around the tropicalcyclone center. The interaction of SSGs with the large-scale beta gyres (LSBGs) leads to theoscillation in translation speed and vacillation in translation direction for tropical cyclone. Theadvection of symmetric vorticity by the asymmetric flow (ASVA) steers the symmetric circulationof tropical cyclone. The ventilation flow vector determined by the asymmetric flow is closecorrelated with the motion vector of tropical cyclone. The nonlinear advection of relative vorticityis an order of magnitude greater than the linear advection of planetary vorticity, However, theasymmetric circulation created by the planetary vorticity advection provides a background conditionfor anomalous motions of the tropical cyclone. The combination of the linear and nonlinear effectsresults in accelerated, decelerated, changing direction and/or counterclockwise looping motions ofthe tropical cyclone.  相似文献