Influence of El Nino/La Nina on the western winter spring cohort of neon flying squid (Ommastrephes bartramii) in the northwestern Pacific Ocean     

Chen  Xin Jun; Zhao  Xiao Hu; Chen  Yong 《ICES Journal of Marine Science》2007,64(6):1152-1160

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Role of Siliceous Fossil Dissolution in Downcore Variations of Grain Size and Water Content: Western Margin of Clarion-Clipperton Fracture Zone, NE Equatorial Pacific     

Hoi-Soo Jung  Kap-Sik Jeong  Yong-Shik Chu  Sung-Hyun Park  Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195

Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors.  相似文献   

Rare earth elements-rich phase and enriching mechanism in sediments from CC area, the Pacific Ocean   总被引：1，自引：0，他引：1  

Meng Xianwei  Chen Zhihu  Wang Xiangqin  Liu Na 《海洋学报(英文版)》2001,20(2):209-214

Compared to North American shale composition (NASC),REE contents of sediments from the CC area in the Pacific Ocean are obviously high except that cerium has equal content to that of NASC.Three-valence rare earth elements were completely enriched in phosphate-phase and cerium in iron-phase.Rare earth elements in the sediments were originally derived from seawater.During lithigenic and minerogenic processes of metalliferous nodules,three-valence rare earth elements in sediments mobilized and incorporated into sediments as authigenous biogenic-apatite,while cerium had change from Ce³⁺ to Ce⁴⁺ and directly precipitated from seawater and entered metalliferous nodules and caused Ceanomalies in REE pattern in sediments.  相似文献   

皱纹盘鲍杂交F1AFLP标记偏分离现象初析   总被引：1，自引：0，他引：1  

刘贤德  刘晓  张国范 《海洋科学》2007,31(10):70-76

运用AFLP标记技术对皱纹盘鲍(Haliotis discus hannaiIno)及杂交F1代共86个个体进行分析,检测了32对AFLP引物组合,共产生2688个AFLP片段,平均每个引物组合产生84个片段。在子代中分离的片段有483个,包括母本标记230个,父本标记135个,双亲本共有的标记118个。卡方检验表明167个母本和100个父本标记符合1∶1的孟德尔分离比例,78个标记符合3∶1的分离比例,其偏分离比例分别达到27.4%,25.9%和33.9%。本研究发现无论是雌性还是雄性偏分离标记都主要是纯合子过剩,初步推测造成偏分离的原因可能与两个鲍鱼群体的某些基因不兼容有关。  相似文献   

海台及其性质的初步分析   总被引：6，自引：0，他引：6  

张抗 《海洋地质与第四纪地质》1991,11(1):1-13

本文对海台及其性质作了初步分析,它具有相对平静或非线性的磁场,一般为无震区,其地壳明显厚于大洋盆地,并具洋陆地壳间的某种过渡性.  相似文献   

距今三万年来西北太平洋洋流系统变化的初步研究     

闾国年 《海洋科学》1989,13(3):13-20

本文探讨了西北太平洋流系统变化的研究方法,并利用这些方法恢复了距今三万年以来这一地区洋流系統变化的过程。  相似文献   

Deep-circulation flow at mid-latitude in the western North Pacific   总被引：1，自引：1，他引：1  

Daigo Yanagimoto  Masaki Kawabe 《Deep Sea Research Part I: Oceanographic Research Papers》2007,54(12):2067-2081

Direct current measurements with five moorings at 27–35°N, 165°E from 1991 to 1993 and with one mooring at 27°N, 167°E from 1989 to 1991 revealed temporal variations of deep flow at mid-latitude in the western North Pacific. The deep-circulation flow carrying the Lower Circumpolar Deep Water from the Southern Ocean passed 33°N, 165°E northwestward with a high mean velocity of 7.8 cm s⁻¹ near the bottom and was stable enough to continue for 4–6 months between interruptions of 1- or 2-months duration. The deep-circulation flow expanded or shifted intermittently to the mooring at 31°N, 165°E but did not reach 35°N, 165°E although it shifted northward. The deep-circulation flow was not detected at the other four moorings, whereas meso-scale eddy variations were prominent at all the moorings, particularly at 35°N and 29°N, 165°E. The characteristics of current velocity and dissolved oxygen distributions led us to conclude that the deep-circulation flow takes a cyclonic pathway after passing through Wake Island Passage, passing 24°N, 169.5–173°E and 30°N, 168–169°E northward, proceeds northwestward around 33°N, 165°E, and goes westward through the south of the Shatsky Rise. We did not find that the deep-circulation flow proceeded westward along the northern side of the Mid-Pacific Seamounts and eastward between the Hess Rise and the Hawaiian Ridge toward the Northeast Pacific Basin.  相似文献   

A discussion on vertical profiles of dissolved Cu,Cd and Ni in the northwestern Pacific, south of Japan     

Wang Zhengfang  Ohyama Junichi 《海洋学报(英文版)》1993,12(4):597-603

Some of the results about vertical profile of heavy metals of seawater to the south of Japan in Oct. 1990 are presented and discussed in relation to the concentration of dissolved Cu, Cd and Ni to biogeochemical environments. It points out that the distribution of dissolved Cu is higher in surface water than that in/upper 500 m layer, and maxima value attains the 8. 2 n mol/dm3 in depth of 4 000 m. The concentrations of dissolved Ni ranges from 3. 4 n mol/dm3 in surface seawater to 8. 5 n mol/dm3 in the deep to the south of Japan. The highest values are observed in the colder waters. This paper shows also that the vertical profile of dissolved Cd is perfect nutrient-type distribution. And dissolved Cd and Phosphate are linearly correlated by the regression equation. The ·Cd : ·N : ·P atomic ratio is 3. 5 × 10-4 : 14 : 1.  相似文献   

气浮结构物的沉降过程分析     

王传荣徐炯  沈国光 《海洋工程》2003,21(2):82-86

通过对空腔内气体的小孔出流和运动方程的分析，计算了气浮结构物在不同情况下的沉陷过程，讨论了其沉陷规律并对有关振荡和稳定性等问题进行了分析讨论。  相似文献   

南太平洋风场时空统计特征分析   总被引：2，自引：0，他引：2  

杨亮  刘金芳  张国友  闫明  尼建军 《海洋湖沼通报》2003,(2):17-23

南太平洋风场时空统计特征对船舶远洋交通运输、远洋出访、南极考察和科学试验等活动有重要实用价值。本文根据 1 950～ 1 995年共 46a的南太平洋船舶气象报资料 ,按 1°× 1°和5°× 5°网格统计的海面风进行分析研究。通过分析每月风各要素的等值线分布图 ,得出南太平洋风场季节变化特点不如北半球各大洋显著 ,但仍有较明显的季节变化 ,只是季节性差异较小 ,冬季比夏季风强盛 ,相应的平均风速 6级和 8级以上大风频率也较大 ;全年风场基本相似 ,低纬度地区 (2 5°S以北至赤道 )为信风区 ,常年盛行东至东南风 ;2 5°S～ 35°S的广大海域上 ,风力较小 ,风向变化最大 ;40°S以南盛行偏西风 ,风力最强。  相似文献