科氏力对河口分汊的影响   总被引：1，自引：0，他引：1       下载免费PDF全文

金元欢  沈焕庭 《海洋科学》1993,17(4):52-56

以长江口、黄河口、珠江口、闽江口等几个分汊河口为例,分析了科氏力在河口分汊中的作用。结果表明,涨落潮流路分歧主要通过形成涨落潮冲刷槽和中央缓流区浅滩而逐渐使河口产生分汊;水面横比降则以横向环流和横向切滩两种形式,或堆积或冲刷,导致河口分汊。  相似文献   

长江口海水的密度   总被引：1，自引：1，他引：1  

陈国华  胡博路  张力军  季荣  金建成 《海洋与湖沼》1992,23(6):573-580

为了核对1980年国际海水状态方程应用于中国近岸海水的可靠性,高精度的磁力浮沉子密度计在15—25℃,盐度5—35,一个大气压条件下,测量了长江口附近海水及其人工稀释海水的相对密度。结果表明,海水密度直接测量值系统地偏高于状态方程计算值,二者之间的偏差随水样盐度值降低而增大,且与海水[Ca~(2+))/s比值成明显正相关关系。经计算机拟合,导出了长江口附近海水及其稀释海水的状态方程,该方程计算值与实验值的平均标准偏差为±3.9×10~(-3)kg/m~3。  相似文献   

罗源湾南岸上元—坑园牡蛎礁与海平面变化     

徐映深  高中和 《台湾海峡》1992,11(4):368-371

上元-坑园牡蛎礁位于高潮位以下3m,主要成分为长牡蛎和近江牡蛎,其~(14)C年龄为3043±82a,B.P.。据此推算出罗源湾一带海岸处于缓慢上升状态,速率为1.15mm/a。根据上元-坑园牡蛎礁的上述特征,并结合断块差异升降运动的表现,作者认为这一地区中、晚全新世以来以“陆动型”海平面变化占主导地位。  相似文献   

长江口南港水道潮流特征分析   总被引：6，自引：0，他引：6  

杨许侯  金成法  马道华 《海洋通报》1999,18(1):1-11

根据１９９６年长江口南港水道枯、丰水期（１月、７月）大、中、小潮两次各２６ｈ以上的全潮水文实测资料,统计分析了实测流的特征和潮流类型、运动形式、潮流垂直变化、余流、Ｍ２分潮流及分潮流对涨、落潮流不等的影响。  相似文献   

锌对虾夷扇贝和刺参幼体的毒性效应   总被引：11，自引：1，他引：11  

朱丽岩  吕建发  唐学玺  高象贤  徐怀恕 《海洋通报》1999,18(4):34-37

以虾夷扇贝和刺参幼体为材料,采用急性毒性试验和亚急性毒性试验的方法,研究了锌对虾夷扇贝稚贝及幼贝和刺参幼虫的毒性效应。结果显示,锌对虾夷扇贝稚贝的２４ｈＬＣ５０ ６．４０ｍｇ／Ｌ,４８ｈＬＣ５０为３．３１ｍｇ／Ｌ,７２ｈＬＣ５０为１．３９ｍｇ／Ｌ,９６ｈＬＣ５０为０．６１ｍｇ／Ｌ;而对幼贝的２４ｈＬＣ５０为３．３２ｍｇ／Ｌ,４８ｈＬＣ５０为２．６４ｍｇ／Ｌ。７２ｈＬＣ５０为１．７６ｍｇ／Ｌ,９６ｈ  相似文献   

Dinoflagellate cysts in recent marine sediment from Guangxi, China   总被引：2，自引：0，他引：2  

Haifeng Gu  Qi Fang  Jun Sun  Dongzhao Lan  Feng Cai  Zhiyong Gao 《海洋学报(英文版)》2003,22(3):407-419

Total of 33 species of dinoflagellate cysts were discovered from surface sediment in the searegion of Guangxi, among them 12 cyst types (Diplopsalopsis sp.1, D. sp. 2, D. sp. 3, Cochlodinium sp., Protoperidinium sp. 1, P. sp. 2, P. compressum , Scrippsiella sp. 1, S. sp. 2, Alexandrium sp. 1, A. sp. 2, A. sp. 3) were first reported from the South China Sea. And one cyst type (Cochlodinium sp.) was first reported in the world. Scrippsiella trochoidea is the dominant species in this area, accounting for 45% of all the cysts. There are 2 cysts of toxic dinoflagellate (Alexandrium tamarensis and Gymnodinium catenatum). But there is no relationship between cyst number and grain size distribution.  相似文献   

南海季风区地域性大气环流的结构     

周发琇  张涛  高荣珍 《中国海洋大学学报(自然科学版)》2001,31(4):467-472

作者使用 NCEP/ NCAR再分析资料 ,在热带 30°S～ 30°N纬带用谐波分析方法分离出超长波之后 ,再采用环流诊断方法 ,发现南海季风区存在地域性环流系统。文中给出冬、夏季风期该系统的三维空间结构和相应的热源分布 ,讨论了该地域性环流系统对南海季风气候及其异常的作用 ,并探讨夏季风爆发北部先于南部的一种可能的气候原因。  相似文献   

Decrepitation Thermometry and Compositions of Fluid Inclusions of the Damoqujia Gold Deposit,Jiaodong Gold Province,China:Implications for Metallogeny and Exploration   总被引：20，自引：0，他引：20  

Yang Liqiang  Deng Jun  Zhang Jing  Guo Chunying  Gao Bangfei  Gong Qingjie  Wang Qingfei  Jiang Shaoqing  Yu Haijun 《中国地质大学学报(英文版)》2008,19(4):378-390

The recently discovered Damoqujia (大磨曲家) gold deposit is a large shear zone-hosted gold deposit of disseminated sulphides located in the north of the Zhaoping (招平) fault zone, Jiaodong (胶东) gold province, China. In order to distinguish the temperature range of cluster inclusions from different mineralization stages and measure their compositions, 16 fluid inclusions and 5 isotopic geochemistry samples were collected for this study. Corresponding to different mineralization stages, the multirange peaks of quartz decrepitation temperature (250-270, 310-360 and 380-430℃(2) indicate that the activity of ore-forming fluids is characterized by multistage. The ore-forming fluids were predominantly of high-temperature fluid system (HTFS) by CO2-rich, and SO2-4-K type magmatic fluid during the early stage of mineralization and were subsequently affected by low-temperature fluid system (LTFS) of CH4-rich, and Cl--Na /Ca2 type meteoric fluid during the late stage of mineralization. Gold is transferred by Au-HS- complex in the HTFS, and Au-Cl- complex can be more important in the LTFS. The transition of fluids from deeper to shallow environments results in mixing between the HTFS and LTFS, which might be one of the most key reasons for gold precipitation and large-scale mineralization. The ore-forming fluids are characterized by high-temperature, strong-activity, and superimposed mineralization, so that there is a great probability of forming large and rich ore deposit in the Damoqujia gold deposit. The main bodies are preserved and extend toward deeper parts, thereby suggesting a great potential in future.  相似文献   

Fault Characteristics in Longmen Mountain Thrust Belt,Western Sichuan Foreland Basin,China   总被引：1，自引：0，他引：1  

万桂梅  汤良杰  杨克明  金文正  吕志洲  余一欣 《中国地质大学学报(英文版)》2008,19(6):611-624

Through field geological survey,the authors found that abundant thrust faults developed in the Longmen (龙门) Mountain thrust belt.These faults can be divided into thrust faults and strike-slip faults according to their formation mechanisms and characteristics.Furthermore,these faults can be graded into primary fault,secondary fault,third-level fault,and fourth-level fault according to their scale and role in the tectonic evolution of Longmen Mountain thrust belt.Each thrust fault is composed of several secondary faults,such as Qingchuan (青川)-Maowen (茂汶) fault zone is composed of Qiaozhuang (乔庄) fault,Qingxi (青溪) fault,Maowen fault,Ganyanggou (赶羊沟) fault,etc..The Longmen Mountain thrust belt experienced early Indosinian movement,Anxian (安县) movement,Yanshan (燕山)movement,and Himalayan movement,and the faults formed gradually from north to south.  相似文献   

一种新型遥感影像快速匹配算法(英文)     

Jin Liu  Li Yan 《地球空间信息科学学报》2008,11(3):197-200

An iterative algorithm to calculate mutual correlation using hierarchical key points and the search space mark principle is proposed. An effective algorithm is designed to improve the matching speed. By hierarchical key point algorithm and mutual correlation coefficients of the matching images, the important points can be iteratively calculated in the images hierarchically, and the correlation coefficient can be obtained with satisfactory precision. Massive spots in the parameter space which are impossible to match can be removed by the search space mark principle. Two approximate continuities in the correlation image matching process, the image gray level distribution continuity and the correlation coefficient value in the parameter space continuity, are considered in the method. The experiments show that the new algorithm can greatly enhance matching speed and achieve accurate matching results.  相似文献