中太平洋深海沉积物中元素组合特征及地质意义

深海沉积物中稀土(REY,包括Y)是继多金属结核、富钴结壳和热液硫化物之后又一有潜力的深海矿产资源。对中太平洋46个富稀土的沉积物样品(∑REY=(730~1 596)×10-6)和53个相对贫稀土的沉积物样品(∑REY=(324~487)×10-6)进行主微量和稀土地球化学分析,利用聚类分析和因子分析法,对元素组合特征进行了分析,划分元素组合和4个主因子。综合特征表明,2类沉积物REY的富集均与磷酸盐有关,REY含量高低取决于磷酸盐含量,但沉积物的形成具有多源多期的特点,富REY沉积物中铝硅酸岩(黏土矿物和沸石)对沉积物中磷酸盐富集REY的过程具有重要的促进作用,而在贫REY沉积物中铝硅酸岩对REY的富集意义不明显。     

Spatio‐temporal variation in density and size structure of the endangered sea cucumber Isostichopus fuscus in Huatulco National Park,Mexico

The brown sea cucumber Isostichopus fuscus (Ludwig, 1875) has been subjected to strong fishing pressure and is currently considered an endangered species by the IUCN Red List of Threatened Species. Spatial and temporal variations in density were analysed and population parameters of I. fuscus were estimated in three localities of the Southern Mexican Pacific. Density was estimated using circular transects covering a 300 m² area in each locality. Body length and weight were also measured. The mean density was 0.018 ± 0.013 individuals·m^?2, and was statistically significantly lower during summer. The mean length and weight were 22.4 ± 3.8 cm and 396 ± 130 g, respectively, and statistically significant differences were found among localities. The weight–length relationship was W = 0.28·L^1.32 and the mean relative condition index (Kn) = 1.04 ± 0.31. The von Bertalanffy growth equation was L_t = 38.7·(1–exp^(?0.4·t)). The lowest values of length, weight and age were found at Dos Hermanas, suggesting that this locality could be favorable for the settlement of larvae and recruitment and growth of juveniles. The present study is the second to estimate densities of I. fuscus and the first one to publish data on size structure and growth for the population at Bahias de Huatulco. The densities were so low in the three sampled localities that none of them would be able to support a fishery, even under a sustainable management scheme. The information collected in the present study could be helpful for management programs of the Huatulco National Park, as all the data used for these currently come mainly from the populations of I. fuscus in the Gulf of California.     

全球三大洋海山钴结壳资源量估算

钴结壳具有Co、Ni、Cu和Mn及其他金属的潜在矿产资源和储存在结壳层中古环境信息的双重意义。与深海多金属结核和热液硫化物矿床相比,具有较高Co、Ni和Pt含量的海山钴结壳有可能成为商业勘探的潜在目标。为合理地估算出全球三大洋海山钴结壳资源量,基于我国西太平洋海山钴结壳拖网采样调查资料和对太平洋海山钴结壳资源分布规律和钴结壳矿区圈定参数指标的深入研究,按海山不同高度、不同洋壳年龄赋予不同结壳厚度,进而计算出全球三大洋海山钴结壳分布面积为3 039 452.14km2和干结壳资源量为(1 081.166 1~2 162.332 2)×108 t。太平洋海山钴结壳分布面积为2 123 087.12km2和干结壳资源量为(513.244~1 026.488)×108 t,大西洋海山钴结壳分布面积为512 509.74km2和干结壳资源量为(116.503 2~233.006 4)×108 t,印度洋海山钴结壳分布面积为403 855.28km2和干结壳资源量为(81.484 9~162.969 8)×108 t。三大洋海山钴结壳的Mn、Co、Ni和Cu金属量分别为(138.848 0~277.696 0)×108 t,(3.967 6~7.935 2)×108 t、(2.793 6~5.587 2)×108 t和(0.825 1~1.650 2)×108 t。根据钴结壳的Co含量、Co通量和厚度相关分析,所赋予的钴结壳厚度占理论推测厚度的6.10%~12.20%,这与Ku等得出"钴结壳生长时间约占其整个生命史4%"的认识非常相近。三大洋海山钴结壳实测厚度与赋值厚度对比分析表明,太平洋海山钴结壳赋值厚度平均值为1.87cm,实测厚度平均值为1.77cm,相对误差为5.35%,大西洋和印度洋相对误差分别为18.18%和23.23%。研究数据表明按海山高度和洋壳年龄所赋的钴结壳厚度基本合理,估算出的钴结壳资源量基本可靠。本文首次估算出三大洋海山钴结壳资源量,为整个海盆和三大洋海山钴结壳资源量估算提供了新方法。     

基于神经网络的南太平洋长鳍金枪鱼渔场预报

南太平洋长鳍金枪鱼是我国远洋渔业的重点捕捞对象;对南太平洋长鳍金枪鱼进行准确的渔场预报;可以提高捕捞效率;提高渔业的生产能力。本研究根据1993-2010年南太平洋长鳍金枪鱼的延绳钓生产数据以及海洋卫星遥感数据（海水表面温度;SST;海面高度;SSH）和ENSO（El Niño-Southern Oscillation）指标;采用DPS（data processing system）数据处理系统中的BP人工神经网络模型;以渔获产量（单位时间的渔获尾数）和单位捕捞努力量渔获量（CPUE;Catch per unit of effort）分别作为中心渔场的表征因子;并作为BP模型的输出因子;以月、经度、纬度、SST、SSH和ENSO指标等作为输入因子;分别构建4-3-1;5-4-1;5-3-1;6-5-1;6-4-1;6-3-1等BP模型结构;比较渔场预报模型优劣。研究结果表明;以CPUE作为输出因子的BP人工神经网络结构总体上较优;其中以6-4-1模型结构为最优;相对误差只有0.006 41。研究认为;以CPUE为输出因子的6-4-1结构的人工神经网络模型;能够准确预报南太平洋长鳍金枪鱼的渔场位置。     

Spreading-rate dependence of hydroacoustic and teleseismic seismicity of ridge-transform systems: East Pacific Rise,Galapagos Ridge,and Mid-Atlantic Ridge

Seismicity in ocean ridge-transform systems reveals fundamental processes of mid-ocean ridges, while comparisons of seismicity in different oceans remain rare due to a lack of detection of small events. From 1996 to2003, the Pacific Marine Environmental Laboratory of the National Oceanic and Atmospheric Administration(NOAA/PMEL) deployed several hydrophones in the eastern Pacific Ocean and the northern Atlantic Ocean.These hydrophones recorded earthquakes with small magnitudes, providing us with...     

热带西太平洋海洋上层热含量的分布特征及其年际变化的分析

选用海面至20℃等温线所处深度水层的平均温度来表征研究海域海洋上层热含量。利用这一特征值，分析1986—1990年期间热带西太平洋边缘海域海洋上层热含量在秋季的分布特征和年际变化。结果表明：（1）热含量呈南高北低分布，在7．5－22．1°N范围内。以130°E断面为代表，热含量的平均递减率为0．179（℃／纬度）；（2）热含量的分布主要取决于环流系统，其等值线因受黑潮和棉兰老海流的影响而由纬向分布转向经向分布。某些区域因受暖涡及冷涡的影响而呈封闭状分布；（3）热含量的年际变化与E1Nino事件存在着很好的相关性，在E1Nino事件发生期间，热含量变得很低，高热含量（大于26．5℃）海区的分布范围明显缩小。     

印尼海道的两度关闭与西太平洋暖池的形成和兴衰

世界海洋表层水温最高的西太平洋暖池,是全球驱动大气环流的最大热源之一,也是全球热盐环流传输带的热源。新生代晚期印尼海道的关闭是暖池得以形成的基本条件。在印尼海道区划出了对印度尼西亚穿越流起阻挡作用的5道屏障,分析了5道屏障的形成过程和年代,据此提出了印尼海道两度关闭的模式。板块运动导致印尼海道关闭,有利于暖池发展,同时也存在不利的负面影响,本区构造运动对暖池的演变具有特有的双向复合控制作用;由此出发勾勒了近1000多万年来西太平洋暖池的形成和兴衰史：11～9MaBP为原始暖池形成期,9～6MaBP为暖池演化的第一衰退期,6MaBP以来为现代暖池的孕育和发展期,其间在1～0.2MaBP穿插着暖池演化的第二衰退期。上述暖池兴衰史的演化模式,得到了暖池区ODP1143站浮游有孔虫组合所反映的古海水温跃层深度的验证。     

Outflow of the Intermediate Oyashio Water from Sagami Bay to the Shikoku Basin

Since the Intermediate Oyashio Water (IOW) gradually accumulates in Sagami Bay, it can reasonably be supposed that the IOW also flows out from Sagami Bay, even though it may be altered by mixing with other waters. We have occasionally observed a water less than 34.2 psu with a potential density of 26.8 at the southeastern area off Izu Peninsula in July 1993 by the training vessel Seisui-maru of Mie University. Observational data supplied by the Japan Meteorological Agency and the Kanagawa Prefectural Fisheries Experimental Station show that the IOW of less than 34.1 psu was observed at northern stations of the line PT (KJ) off the Boso Peninsula and to the east of Oshima in the late spring 1993. Based upon these observations, it is concluded that the IOW flows out from Sagami Bay into the Shikoku Basin along southeastern area off the Izu Peninsula. The less saline water (<34.2 psu) was also observed to the west of Miyake-jima during the same cruise, and the westward intrusion of IOW from south of the Boso Peninsula to the Shikoku Basin through the gate area of the Kuroshio path over the Izu Ridge was detected. This event indicated that the IOW branched south of the Boso Peninsula and flowed into Sagami Bay and/or into the gate area over the Izu Ridge. The southward intrusion of IOW into the south of the Boso Peninsula is discussed in relation to the latitudinal location of the main axes of the Kuroshio and the Oyashio. This revised version was published online in July 2006 with corrections to the Cover Date.     

Observational Study on the Downward Solar Radiation at the Sea Surface in the Western Pacific

In situ observation of downward solar radiation in the Western Pacific were carried out with voluntary merchant ships for five years from autumn 1990 through autumn 1995. Daily means of the short wave radiation were computed from the observed solar radiation. Then, the effects of shadows of the ship's superstructures on the observed radiation were corrected if needed. A 5-year average of short wave radiation along the main sea-lanes in the Western Pacific was calculated based on the observed daily mean solar radiation. Maximum values of 270–280 Wm^–2 are found around 15°–20°N in May and June, while those of 290 Wm^–2 are observed south of 18°S in November and December along the lanes. Small annual variations are found in the equatorial region. Annual mean values at the equator are about 230 Wm^–2 between New Guinea and Indonesia, and 200 Wm^–2 east of New Guinea. The 5-year average of short wave radiation was compared with the climatologies given in previous studies. We have concluded that some of results of previous studies are significantly underestimated.     

东太平洋多金属结核中铁、锰元素的分形演化及其意义

运用分形理论,通过建立不同的相空间,计算了东太平洋多金属结核中的铁、锰元素的时间序列在各相空间中的关联分维,并与其在沉积物岩心中的关联分维进行了对比.通过研究发现,多金属结核中铁、锰元素和沉积物中Fe₂O₃及MnO在分形演化过程中均存在分维吸引子,认为沉积物中的Fe₂O₃和MnO可以用3个变量来描述,它们可能代表了火山、生物和陆地的三种来源,而描述结核中的铁、锰元素却需要14个变量,反映多金属结核中铁、锰元素的来源和/或赋存非常复杂,至少有14个因素在起作用,可能暗示了结核在形成过程中存在复杂的生物化学作用,为多金属结核的生物成因提供了间接的数学证据,同时也合理解释了结核生长结构所具有的自相似韵律现象.