南海东部海域柱样沉积物浊流沉积探讨

利用1998年南海东部陆坡69号柱样、深海盆149号柱样、南部岛礁323号柱样沉积物的粒度、化学、古生物、矿物等鉴定分析测试资料,分析了南海东部海域发生浊流沉积的地质背景、产生浊流沉积的条件和诱发因素,进而发现南海东部浊流沉积发育,在南北陆坡及中部深海盆地均有浊流沉积层。从其出现层位看,为氧同位素2—4期,即晚更新世中晚期。从浊流沉积出现层数分析,具有自北向南浊流发生频次减弱的趋势。从浊流沉积物成分看,南海东部浊流沉积物具有多样性,北部陆坡以陆源为主,中部深海盆以陆源及火山源为主,南部岛礁以生物源为主。     

水成沉积与风成沉积及古土壤的磁组构特征

晚第四纪水成沉积、风成沉积、古土壤等的磁组构研究表明,不同成因的沉积物具有明显不同的磁组构特征。一般地,水成沉积的体积磁化率Ｋ受物源和水动力因素控制,Ｐ和Ｆ均＞１．０２,ｑ＜０．５;风成沉积的Ｋ受物源控制,内陆黄土的Ｋ明显高于沿海黄土及海岸风沙Ｋ,Ｐ和Ｆ均＜１．０２,ｑ的平均值＞０．５５;古土壤的Ｋ受母质沉积类型和成土环境的氧化还原条件控制,内陆古土壤的Ｋ偏高,沿海古土壤的Ｋ偏低,内陆古土壤的Ｋ远高于沿海古土壤的Ｋ,Ｐ和Ｆ均＜１．０２,ｑ的平均值在０．５左右。运用典型沉积的磁组构特征对比分析未知沉积物,可以得到未知沉积物的物源、沉积过程和环境信息。     

重金属锌,铅对菲律宾蛤仔的急性毒性试验

本文研究了必需元素Ｚｎ及非必需元素Ｐｂ对菲律宾蛤仔的急性毒性作用，得到Ｚｎ对其的４８ｈＬＤ５０和９６ｈＬＤ５０分别为１４７．９１、１６．４０ｍｇ／ｄｍ＾３；Ｐｂ对其的４８ｈＬＤ５０和９６ｈＬＤ５０分别为３１．６２、１４．２８ｍｇ／ｄｍ＾３。估算得到Ｚｎ、Ｐｂ对菲律宾蛤仔的安全浓度分别为０．８２、０．７１ｍｇ／ｄｍ＾３。     

闽江口段溶解态镉,铅和铜的收支平衡

利用潮输沙量的计算方法,估算了闽江口入海口内3个断面所包围区域溶解态镉、铅和铜的收支平衡,从而研究了这些重金属的河口行为。     

Identification of Pb sources in Yellow Sea sediments using stable Pb isotope ratios

Rapid economic developments in East Asian countries have inevitably resulted in environmental degradation in the surrounding seas, and concern for both the environment and protection from pollutants is increasing. Identification of sources of contaminants is essential to environmental pollution management. In this study, the provenance of anthropogenic lead (Pb), a major pollutant of Yellow Sea sediments, was determined for river mouth sediments, including those of the Changjiang, Huanghe, Han, and Geum Rivers, and for age-determined shelf core sediments through the measurement of Pb isotope ratios in the HCl-leached fraction using multi-collector inductively coupled plasma-mass spectrometry (MC ICP/MS). Anthropogenic Pb has accumulated in shelf core sediments since 1910, and its isotope ratios were estimated as 0.863–0.866 and 2.119–2.125 for ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb, respectively, from the mixing relationships of the two endmembers. River mouth sediments exhibited enough distinction in anthropogenic Pb isotope ratios to be discriminated: 0.874 (2.144) in the Huanghe, 0.856 (2.129) in the Han, 0.857 (2.122) in the Geum, and 0.854 (2.101) in the Changjiang for ²⁰⁷Pb/²⁰⁶Pb (²⁰⁸Pb/²⁰⁶Pb), respectively. Although isotope ratios of geogenic Pb in sediments dating before 1910 showed narrow ranges (0.842–0.845 and 2.088–2.100 for ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb, respectively), distinct isotope ratios in each core permitted source identification of sediments in the Yellow Sea based on geographic locations and the geogenic Pb of each river. By comparing the isotope ratios of the estimated anthropogenic Pb to source-related materials, the provenances of anthropogenic Pb in Chinese river sediments were presumed to be Chinese coal or ore, which is also a major source of atmospheric particulate Pb. The anthropogenic Pb in the shelf core sediments in the northern Yellow Sea originated from northern Chinese cities such as Beijing and Tianjin through atmospheric pathways. Pb isotope ratios indicated that Pb in Korean river sediments was characteristic of local Korean ores.     

广东红海湾、珠江口及电白—阳江近海第四纪沉积

根据物探和钻探资料，研究区内第四纪沉积物可分为两部分，下部地震反射结构复杂，斜层理发育，粒度较粗，为晚更新世产物；上部的地震反射结构简单，呈水平状或近水平状结构，粒度较细，为全新世沉积。     

Pb and other ore metals in modern seafloor tectonic environments: Evidence from melt inclusions

Many modern seafloor tectonic environments are host to hydrothermal systems and associated polymetallic sulfide deposits. Metal transport and precipitation are controlled by magmatic processes such as pre-eruptive degassing and the hydrothermal cycle. The original availability of Pb and other ore metals in a given setting is dependent on concentrations in the original magmatic source or additional enrichment processes. We have examined the Pb budget of melt inclusions from nine modern seafloor settings representing back-arcs, mid-ocean ridges and seamounts. Melt inclusions provide information on the characteristics of parental magmas, including insights into metal budgets. Trace element data in melt inclusions hosted in plagioclase, olivine and pyroxene were obtained by laser-ablation inductively-coupled mass-spectrometry.Results from back-arcs emphasize the impact of slab-subduction and dehydration processes on the chemical characteristics of generated magmas. Volatile- and fluid-mobile element-rich melt inclusions at Manus basin and Okinawa trough reflect a robust contribution of elements from the subducting slab as evidenced by relatively low Ce/Pb ratios. At Bransfield strait, on the other hand, melt inclusions are volatile poor, and fluid-mobile element ratios are similar to mid-ocean ridge values indicating little or no contribution from the slab. High Cu concentrations at Manus basin and Okinawa trough can be explained by fluxing of ferric iron from the subducting slab benefiting the production of sulfate over sulfide.Metal budgets for seamounts located on and nearby the axis of mid-ocean ridge segments appear to be independent of any input of mantle plume material. Results from the southern Explorer ridge (strong lower mantle influence, transitional- and enriched-MORBs), Pito and Axial seamounts (moderate lower mantle influence, transitional-MORBs) and a Foundation near-ridge seamount (little to no mantle influence, normal-MORB) show that, despite similar tectonic environments and varying contributions of mantle plume material, Cu, Zn and Pb values do not vary significantly between the enriched and non-enriched magma components of a given setting.     

杭州湾南岸潮滩的~(210)Pb分布及其沉积学意义

杭州湾南岸潮滩的~(210)Pb垂向分布具有随深度波动的特征。湖滩颗粒物在吸附模拟系统中的~(210)Pb分配系数,主要受颗粒物含量的影响。本文从潮滩沉积~(210)Pb初始比度在低于平衡点一侧波动的机理,以及被沉积间断所分隔的有效封闭段的存在出发,提出选择常态沉积层的高~(210)Pb比度窗口,建立以CIC模式估计潮滩沉积速率的方法。     

近1300年来古胶州港位置的变迁

本文主要依据有关方志、文史资料，着重考证了近１３００年来古胶州港位置的变迁，研究发现，古胶州港的位置自唐代至清末近１３００年间，沿胶州湾西、北岸大致经历了７次变更，特别自明代开始，港口位置变迁尤为频繁，作者初步分析认为这与历史时期胶州湾内西、北岸的不断淤涨和胶莱南河、大沽河口的冲淤作用有关。