南黄海浮游植物季节性变化的数值模拟与影响因子分析

用三维物理-生物耦合模式研究南黄海浮游植物(以叶绿素a为指标)的季节变化.对于物理模式采用Princeton ocean model(POM),对于生物模式考虑溶解无机营养盐(氮、磷、硅)、浮游植物、食草性浮游动物和碎屑.给定已知的初始场和外加边界强迫,模拟了观测到叶绿素a的主要时、空分布特征,如浮游植物的春、秋季水华和夏季次表层叶绿素a极大值现象等.研究表明,浮游植物春季水华最先发生于黄海中央海域,主要原因是该海域透明度较高,流速较小.春季水华开始于垂直对流减弱和层化开始形成之前(约3月底至4月上旬),显著地依赖水层的稳定性.水体层化以后(约5～9月)叶绿素a浓度高值区分布在南黄海的南部和锋区.夏季的南黄海中央海域,由于上混合层营养盐几乎耗尽,限制了浮游植物的生长,在紧贴温跃层下部的真光层,具有丰富的营养盐和合适的光照,次表层叶绿素a极大值得以形成.秋季(约9～11月份,略迟于海表面开始降温的时间,随地点不同而异)随垂直混合的增强,有利于营养盐向上输运,浮游植物出现一次较小的峰值.     

华北-扬子板块碰撞结构的识别:来自南黄海海域的证据

华北-扬子板块碰撞是中国东部中生代最重要的地质事件之一,碰撞形成了世界最大的超高压变质带秦岭-大别-苏鲁造山带。在苏鲁造山带向海域延伸部分,一直缺乏相关地球物理资料来约束碰撞造山带的深部特征。本文总结了华北-扬子板块碰撞的经典模型,根据南黄海海域最新二维地震反射资料和前人的研究成果,认为在造山带南缘南黄海盆地中,扬子板块上、下地壳发生拆离,形成类似鳄鱼嘴式形态,华北板块向南楔入到扬子板块之中。在区域重磁异常图中,千里岩隆起带与苏鲁造山带具有相似的重磁异常分布,认为千里岩隆起带为华北-扬子碰撞造山带在海域上的延伸;在南黄海盆地北缘二维地震剖面中,千里岩隆起与南黄海盆地具有完全不同的地震反射特征,南黄海盆地发育完整地层层序,而千里岩隆起内部反射杂乱,变形强烈。在南黄海盆地自西向东三条南北向地震剖面中,南黄海盆地与千里岩隆起带边界反射均具有南倾特征,表明扬子板块物质置于造山带之上;南黄海盆地北部烟台坳陷发育中侏罗统,约束华北-扬子碰撞所导致的挤压活动主要发生于晚三叠世。在千里岩隆起内部反射特征整体上具有背形形态,具有向北逆冲挤压特征,千里岩隆起内反射断续自南黄海盆地基底之下延伸至造山带近地表位置,形态类似于变质核杂岩从深部拆离到地表;千里岩隆起深部,在10 s深度附近可识别一系列近水平反射,具有莫霍面反射特征,莫霍面反射延伸至南黄海盆地北缘消失,推测千里岩隆起之下为华北板块地壳,而华北-扬子板块碰撞过程导致南黄海盆地之下莫霍面反射缺失。多方面的证据支持南黄海海域内扬子板块的鳄鱼嘴式地壳形态,以及华北板块地壳向南楔入到扬子板块地壳中。     

南黄海及相邻陆区松散沉积层磁性地层的研究

本文通过研究区5个钻孔松散沉积岩心磁性地层的划分对比,获知布容与松山极性带的界线,南黄海和陆区北部位于80.0—99.5m。陆区的南部此界线于270.4m深处。松山和高斯极性带的界线,海区未揭露到,其沉积起始时间都小于1.7Ma。而陆区的南、北部分别位于117m和328.2m。高斯和吉尔伯特极性带的界线,陆区北部为140m,而南部区为460.15m。沉积起始时间为3.4Ma。吉尔伯特底界仅北部陆区所揭示,为190.5m。松散沉积层与下伏白垩纪(?)石灰岩接触面位于400.35m,沉积起始时间约17.0Ma。     

南黄海盆地油气地质研究进展

青岛海洋地质研究所近年来广泛收集了国内外在南黄海海域的地质与地球物理资料 ,对南黄海盆地的石油地质特征进行了系统的研究 ,并应用海洋“863”高科技成果软件——《海上油气资源综合快速评价系统》进行了盆地模拟和资源评价 ,取得了多项创新性的进展。( 1 )广泛应用国内外在南黄海海域及邻区的重磁资料和地震资料 (包括新采集的多道地震资料 ) ,采用综合地球物理解释技术 ,首次编制了全盆地 1∶ 50万的基底构造图、深度构造图、厚度图及沉积相图 ,对盆地的构造区划进行了重新划分 ,为南黄海油气勘查部署打下了良好基础。( 2 )在南黄海北…     

Mineralogical characteristics of polymetallic sulfides from the Deyin-1 hydrothermal field near 15°S,southern Mid-Atlantic Ridge

A seafloor hydrothermal field, named Deyin-1 later, near 15°S southern Mid-Atlantic Ridge(SMAR) was newly found during the 22 nd cruise carried out by the China Ocean Mineral Resources Research Development Association(COMRA). Sulfide samples were collected at three stations from the hydrothermal field during the26 th cruise in 2012. In this paper, mineralogical characteristics of the sulfides were analyzed with optical microscope, X-ray diffractometer, scanning electron microscope and electron microprobe to study the crystallization sequence of minerals and the process of hydrothermal mineralization. According to the difference of the ore-forming metal elements, the sulfide samples can be divided into three types:(1) the Ferich sulfide, which contains mainly pyrite and chalcopyrite;(2) the Fe-Cu-rich sulfide consisting predominantly of pyrite, chalcopyrite and isocubanite, with lesser amount of sphalerite, marmatite and pyrrhotine; and(3) the Fe-Zn-rich sulfide dominated by pyrite, sphalerite and marmatite, with variable amounts of chalcopyrite, isocubanite, pyrrhotine, marcasite, galena and gratonite. Mineral precipitations in these sulfides are in the sequence of chalcopyrite(isocubanite and possible coarse pyrite), fine pyrite,sphalerite(marmatite), galena, gratonite and then the minerals out of the dissolution. Two morphologically distinct generations(Py-I and Py-II) of pyrite are identified in each of the samples; inclusions of marmatite tend to exist in the coarse pyrite crystals(Py-I). Sphalerite in the Fe-Zn-rich sulfide is characterized by a"chalcopyrite disease" phenomenon. Mineral paragenetic relationships and a wide range of chemical compositions suggest that the environment of hydrothermal mineralization was largely changing. By comparison, the Fe-rich sulfide was formed in a relatively stable environment with a high temperature, but the conditions for the formation of the Fe-Cu-rich sulfide were variable. The Fe-Zn-rich sulfide was precipitated during the hydrothermal venting at relatively low temperature.     

Distribution patterns of chlorophyll <Emphasis Type="Italic">a</Emphasis> in spring and autumn in association with hydrological features in the southern Yellow Sea and northern East China Sea

Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankton stock (Chl a concentration) and the impact of hydrological features such as water mass, mixing and tidal front on these patterns. The results indicated that the Chl a concentration was 2.43±2.64 (Mean ± SD) mg m^?3 in April (range, 0.35 to 17.02 mg m^?3) and 1.75±3.10 mg m^?3 in September (from 0.07 to 36.54 mg m^?3) in 2003. Additionally, four areas with higher Chl a concentrations were observed in the surface water in April, while two were observed in September, and these areas were located within or near the point at which different water masses converged (temperature front area). The distribution pattern of Chl a was generally consistent between onshore and offshore stations at different depths in April and September. Specifically, higher Chl a concentrations were observed along the coastal line in September, which consisted of a mixing area and a tidal front area, although the distributional pattern of Chl a concentrations varied along transects in April. The maximum Chl a concentration at each station was observed in the surface and subsurface layer (0–10 m) for onshore stations and the thermocline layer (10–30 m) for offshore stations in September, while the greatest concentrations were generally observed in surface and subsurface water (0–10 m) in April. The formation of the Chl a distributional pattern in the SYS and NECS and its relationship with possible influencing factors is also discussed. Although physical forces had a close relationship with Chl a distribution, more data are required to clearly and comprehensively elucidate the spatial pattern dynamics of Chl a in the SYS and NECS.     

综合找矿方法在鄂东南危机矿山接替资源勘查中的应用——以铜绿山、鸡冠咀、大冶铁矿等矿山为例

以鄂东南地区铜绿山矿田内的铜绿山铜铁矿、鸡冠嘴铜金矿、铁山矿田内的大冶铁矿近几年接替资源勘查方法及成果为例,阐述综合找矿方法在不同矿山深部找矿中的应用效果.     

春季南黄海、东海浮游植物群落结构与环境因子

2017年春季(04-20—05-09)在南黄海和东海海域(119°30′～125°00′E,26°00′～36°00′N)67个站位进行水文、化学和生物的综合调查,使用水采方法研究调查海域的浮游植物群落结构,并将群落数据与环境因子(温度、盐度和营养盐)进行相关性分析。调查中共鉴定出浮游植物4门55属146种,主要由硅藻和甲藻组成,还有少量的金藻和蓝藻,生态类型以温带近岸性和广布性物种为主。优势物种组成方面,南黄海和东海海域存在差异,其中南黄海海域优势物种为诺氏海链藻(Thalassiosira nordenskioldii)、太平洋海链藻(Thalassiosira pacifica)、微小原甲藻(Prorocentrum minimum)和具槽帕拉藻(Paralia sulcata)等,东海海域优势物种为柔弱伪菱形藻(Pseudo-nitzschia delicatissima)、具槽帕拉藻(Paralia sulcata)、柔弱角毛藻(Chaetoceros debilis)和具齿原甲藻(Prorocentrum dentatum)等。调查区浮游植物细胞丰度为(0.07～547.87)×10~3个/L,平均值为29.45×10~3个/L,高值区集中在南黄海中部和闽浙沿岸区域,其中在南黄海中部的10～30 m水层发生硅藻水华。与环境因子的相关性分析表明,南黄海海域浮游植物细胞丰度与硅酸盐和磷酸盐浓度呈现显著正相关性,与其他环境因子相关性不明显;东海海域浮游植物细胞丰度与温度和盐度呈现显著负相关性,与硅酸盐、铵盐和硝酸盐浓度呈现显著正相关性。调查区香侬-威纳多样性指数介于1.05～4.86,平均值为2.48,高值区出现在调查区的北部近岸区域;Pielou均匀度指数介于0.02～0.97,平均值为0.57,高值区集中在南黄海北部近岸区域和东海外侧区域。     

北斗在南/北极地区的基本定位性能评估

基于BDS、GPS系统的星座结构,对当前的BDS二代导航系统（BD2）、全部建成后的BDS系统在极地科考站（黄河站、昆仑站、中山站、长城站）和北极圈的可见卫星数、DOP值、定位精度等进行评估,并将建成后的BDS、GPS及其组合系统在南/北极的基本定位性能进行对比分析。仿真结果表明,当前的BD2只实现了极地的部分覆盖,对极地提供导航定位的能力有限,大范围内的定位精度大于30.0 m; BDS在极地的定位精度将与GPS相当,可见卫星数可达13颗左右,PDOP值优于1.6,定位精度优于8.0 m;GPS/BDS组合后在极地的PDOP值优于1.4,定位精度优于6.0 m。
     

南华北盆地青白口系—侏罗系层序界面时空分布特征研究

以位于秦岭—大别造山带之北、华北陆块南部、地跨华北陆块稳定块体、陆块南部边缘变形带的南华北盆地为研究对象,通过对研究区42条不同时代的野外剖面详细观测,运用层序地层学理论,把南华北盆地作为一个整体系统,对青白口系—侏罗系层序界面特征及时空分布规律进行了系统分析,共识别出了8种类型层序界面的物质表现形式,分别是不整合面、渣状层、古喀斯特作用面、冲刷侵蚀面、超覆面、岩性岩相转换面、最大海泛面、最大湖泛面。并重点讨论了各类型界面的时空分布特征。结果表明:在时间演化上,从早到晚由海相—海陆过渡相—陆相,层序界面经历了海相沉积不整合、古喀斯特作用面、渣状层到陆相不整合面、冲刷侵蚀面等;在空间上,同一层序界面在不同相带表现形式不同,同一种类型的界面可在不同相带出现,但不同相带表现特征有一定差异性。