上海市近岸海域表层沉积物类型与元素丰度相关关系特征

通过上海市近岸海域多目标区域地球化学调查,共采集947件表层沉积物样品,分析测试了52种化学元素以及pH值和有机碳等指标。总结了该区域表层沉积物及深层沉积物类型和分布特征,沉积物类型主要为细砂、粉砂质砂、砂质粉砂、粉砂、粘土质粉砂,其中粘土质粉砂分布最为广泛。元素含量与砂含量呈正相关的元素主要为SiO2、Sr、Na2O等。其它指标大都与粘土含量呈正相关关系。     

The contrasting geochemical behaviours of iodine and bromine in recent sediments from the Namibian shelf

The vertical distribution of iodine, bromine and organic carbon has been examined in sediment cores from a range of environments on the Namibian shelf. The relationship between Br and C org. is linear, and that between I and C org. is variable, for all surface sediments; I/C org. ratios show a decrease of about one order of magnitude between the outer shelf oxidising sediments ($\text{250 × 10}{}^{\mathrm{?4}}$) and the organic-rich inner shelf sediments ($\text{20 × 10}{}^{\mathrm{?4}}$). The contrasting behaviour of the halogens in surface sediments is explained by differences in the amount of halogen absorbed by living organisms within the euphotic zone and on seston on the seabed. It is suggested that sorption by seston occurs only in oxidising sediment where free O₂ is available. Hence, iodine is sorbed by seston in the outer shelf environment, but is not sorbed by the reducing sediments of the inner shelf. Here the iodine in the sediment represents only that taken up by plankton. On the outer shelf, 50–80% of the total iodine in the organic matter is sorbed by seston. The principal site of Br uptake is not known.The distribution of C org. in subsurface sediments broadly reflects that found at the surface, although there is a slight decrease with depth in the outer shelf cores due to dilution by terrigenous materials. In the inner shelf cores, there is no change in the relationship of iodine and bromine to organic carbon at depth. Those from the mid shelf, and especially the outer shelf, on the other hand, show decreases in both I/C org. and Br/C org. ratios, reaching values at about 70 cm depth that are similar to those in surface reduced sediments from the inner shelf. Over this depth interval I/C org. ratios decrease by a factor of five while Br/C org. ratios show a two fold decrease. These changes in the ratios at depth imply that diagenesis within the reducing cores is negligible compared with that of oxidised sediments. The implications of diagenesis with regard to halogen recycling in sediments are briefly discussed.     

深海沉积物贯入阻力影响因素及其变化规律

深海沉积物土工力学特性是深海资源开发设备设计的重要依据。根据现有的深海土工力学原位测量和取样实验的数据,分析沉积物物性参数与贯入阻力的相关关系,建立含水率、湿密度和孔隙比与压力沉陷的关系式。结果表明:研究区深海沉积物以砂质粉砂、黏土质粉砂为主,具有高含水率、大孔隙比、低密度等特征;物理参数与贯入阻力之间有较好的相关关系,其中,含水率、孔隙比、孔隙度与贯入阻力呈反比相关关系;而湿密度与贯入阻力呈正比相关关系;以含水率、湿密度和孔隙比为自变量的多变量回归分析方程能更好地表达沉积物物理特性与贯入阻力的相关关系;基于Bekker沉陷模型,建立接地比压与贯入阻力的关系,能客观反映深海沉积物的沉陷特性与承载特性。     

Deglaciation of the southeastern Norwegian Sea towards the end of the last glacial age

In a region of generally thin Holocene sediment cover along the outer Norwegian continental margin, a 565 cm long piston core was taken, which contained more than 4 m of Holocene clayey silty sediments. A several decimetres thick sandy horizon separated the glacial marine clays with ice-dropped components and the fine-grained Holocene sediments which have bulk sedimentation rates of more than 40 cm/1000 years. The scarcity of biogenous sediment components in the glacial sediments and the increasing frequency of benthonic as well as planktonic fossils in the Holocene deposits points to important changes in the Norwegian Sea hydrography during the time of the Scandinavian deglaciation.     

海相细粒沉积层理类型及其油气勘探开发意义

海相细粒沉积层理是恢复沉积环境的重要标志,更是影响着细粒沉积岩的储层品质及可压裂性。细粒物质通过生物作用、生物化学作用和机械分化作用形成之后,以单颗粒、絮凝颗粒、泥岩内碎屑、岩屑、有机—矿物集合体（“海洋雪”）及浮游动物粪球粒等形式,通过风力、低密度流、重力及底流等搬运至海洋,最终以垂直沉降和/或侧向加积的方式沉降下来。细粒物质可形成2种纹层（泥纹层和粉砂纹层）、2种纹层组（泥纹层组和粉砂纹层组）和2种层（递变层和均质层）,并构成5大类层理（块状层理、递变层理、韵律层理和年纹层、水平层理和交错层理）。黑色海相细粒岩泥纹层和粉砂纹层由于物质组成、孔隙类型及结构、面孔率、孔径分布、微裂缝类型及密度等差异,从而造成不同层理类型细粒岩储层品质差异。同时,不同层理细粒岩由于纹层发育程度、单纹层厚度、泥纹层和粉砂纹层比例、连续性、形态和几何关系等差异,从而造成其岩石力学性质及裂缝扩展规律差异。     

Major ion composition and carbonate equilibrium in the sediment pore water of the Razdol’naya River estuary of Amur Bay,the Sea of Japan

The complex study of the river water and pore solutions from the bottom sediments in the lower reaches of the Razdol’naya River was conducted in February 2010. The major ion composition of the waters indicates the submarine origin of the near-bottom and pore waters in the lower reaches of the Razdol’naya River in the winter. The river estuary extends upstream for more than 20 km. It was established that the studied sediments are reduced oozes containing pyrite, hydrotroilite, and iron monosulfide, which is direct evidence for sulfate-reduction in the sediments. The diagenesis of organic matter is the main reason for the considerable decrease in the amount of sulfates and the increase in the alkalinity of the sediment pore water. The sedimentary pore water sampled from the deep river pits is characterized by excess alkalinity that cannot be explained by sulfate-reduction and methane genesis. It was suggested that the chemical weathering of silicate minerals and the bacterial mineralization of salts of organic acids could result in the excess alkalinity of the sediment pore water.     

Geochemistry of surface sediments in the southwestern East/Japan Sea

We analyzed 77 surface sediment samples collected in the southwestern East/Japan Sea from the Korea Strait through the Ulleung Basin and the Korea Plateau for grain size, calcium carbonate, organic carbon, and major (Na, Mg, Al, Fe, K, Ca, and Ti) and trace elements (P, Mn, Sr, Li, Sc, V, Cr, Co, Ni, Zn, Cu, and Pb).The chemical composition of the surface sediments was found to be highly variable spatially. Cluster analysis of surface sediment chemical compositions indicated five major geochemical sedimentary environments: basin, lower slope, coast and upper slope, inner shelf, and outer shelf. Continental-shelf sediments were rich in shell fragments and had relict and coarse-grained characteristics. Recent fine-grained sediments were only distributed in coastal, slope, and basin areas. Concentrations of Al, K, Ca, Ti, Cr, and Sc were highest in the coastal and upper slope areas and decreased with water depth. Elemental ratios using major and trace elements indicated that coastal and upper slope detrital sediments were mixtures of sediments derived from the Changjiang (Yangtze) and Nakdong Rivers. Although the concentrations of organic carbon, P, Mn, V, Co, Ni, Cu, and Pb increased with water depth, their distribution patterns indicated authigenic (V, Cu, and Pb) and diagenetic (Fe, P, Mn, Co, and Ni) origins. The distribution pattern with water depth suggested that the chemical composition of surface sediment was determined by sedimentologic and geochemical processes, such as the supply of detrital and biogenic materials, and authigenic and post-depositional diagenetic processes in sediments.     

Environmental change of the fluvial-estuary system in relation to Arase Dam removal of the Yatsushiro tidal flat,SW Kyushu,Japan

Chemical composition of 24 elements for sediments and suspended solids, water parameters and the diatoms from Yatsushiro Bay tidal flat, Kuma River, and Arase Dam have been determined to examine changes from 2002 to 2013. In 2002, sediment delivered to the bay by the Kuma River was restricted by the Arase Dam; however, in April 2010 two gates were opened and also repeated seasonal flushing allowing resumption of natural sediment transport. Bulk chemical composition of the tidal flat sediments has changed since 2002, with marked decreases in concentrations of As, Zn, Pb and total sulfur. Decreased heavy metal contents in 2012 and 2013 for bay sediments after opening the dam and repeated flushing is attributed to dilution by previously impounded quartz and feldspar. Restoration of natural sediment transport by opening the dam and repeated flushing has thus brought about a recovery in the Yatsushiro marine environment.     

The late Wisconsinan Savanna Terrace in tributaries to the upper Mississippi River

The Savanna Terrace, composed of alternating red and gray clayey sediments of late Wisconsinan age, can be found in five states along the upper Mississippi valley from Pepin County, Wisconsin, to Jackson County, Illinois. The terrace is the highest glaciofluvial-lacustrine deposit without a loess cover in the upper Mississippi valley. Chemical, physical, and mineralogical data show that two different sources provided sediment. The red clay is believed to have come from Lake Superior sources, while the gray clay is believed to have come from sources farther west. Large-scale flood events from glacial Lakes Agassiz, Grantsburg, and Superior were probably the main contributors of the sediments. The red clay in the terrace is similar in composition to red glaciolacustrine sediment found in eastern and northern Wisconsin. It also is mineralogically similar to the Hinckley Sandstone and the Fond du Lac Formation, which occur under and around Lake Superior. Radiocarbon dates obtained from the lower Illinois valley indicate that the terrace sediments were deposited sometime between about 13,100 and 9500 yr ago. Soils developed on the terrace are variable in their physical, chemical, and mineralogical properties, which reflect the composition of the clayey sediments.     

Hydrothermally altered clayey sediments in the rift zone of Iceland (influence of microbiota on accumulation of minor elements)

Results of the first detailed study of mineral and chemical compositions in the rift zone of Iceland near the town of Hveragerði are presented. The major clayey components represented by dioctahedral smectites (mainly, montmorillonite with variable Fe contents) are associated with the subordinate kaolinite. The geological setting, timing, and composition of metasomatic clay minerals and their synthesized counterparts precipitated from solution in the course of interaction of hot groundwaters with basaltic volcanics and sedimentary clayey rocks are considered. Based on textural-structural features and (or) compositions, the sediments are divided into three types: (1) massive unsorted sediments with abundant fine-grained sand to silt-sized clay pellets, (2) horizontally laminated clayey sediments, and (3) organogenic sediments. The massive unsorted sediments enclose remnants of microorganisms replaced by smectite, while laminated clayey sediments host a siliceous layer with abundant mineralized remains of filamentous microorganisms. Clayey rocks of hydrothermally altered hyaloclastites and sediments related to their redeposition are similar in the composition of petrogenic elements. However, they differ notably from each other in the contents of some minor elements (Au, As, Se, Sb, and Hg). Increase in the share of minor elements in sediments is explained by the active influence of bacteria and fungi on their accumulation. The data obtained shed light on some specific features in the composition of clayey rocks, which can be used for mud cure of arthritis and rheumatism in the Health and Rehabilitation Clinic of the Nature Health Association of Iceland, Hveragerði.     

Mass property variability of some estuarine sediments

Bottom sediments from two areas of the York River Estuary of southeastern Virginia were systematically sampled to depths of 40 cm and analyzed for their mass properties, i.e., water content, unit weight, and shearing strength. The samples fell into: (1) a coarse-grained group of clayey sands, silty sands, and sand—silt—clays; and (2) a fine-grained group of silty clays and clayey silts. Analysis of variance between both groups revealed distinct differences in the mass properties. Means, variances, and coefficients of variation for each parameter were determined and made possible a statistical characterization of each sediment type.The data presented may be used to predict expectable values of mass properties for similar sediments, having experienced similar depositional histories, e.g., from neighboring estuaries and Chesapeake Bay.     

Depositional processes on an ancient and modern muddy shelf, northern California

The modern Eel River shelf and analogous Pleistocene Rio Dell Formation in northern California provide an ideal opportunity to combine the advantages of studying a modern environment with those of studying an ancient sequence, and thereby enables further understanding of muddy-shelf processes. The modern shelf is the site of accumulation of a thick deposit of Holocene mud. Both large-scale sediment distribution patterns and small-scale stratigraphy on the shelf indicate that river floods play an important role in sediment accumulation, even on a high-energy, ‘storm-dominated’ coast. The major factors in preservation of this flood ‘signature’ are the cohesive behaviour of fine-grained sediments and episodically rapid rates of sediment input. The Rio Dell Formation includes approximately 400 m of mostly fine-grained shelf deposits that accumulated offshore from a palaeo-Eel River mouth. The shelf sediments comprise four depositional sequences. Sequence 1 records progradation from outer to inner shelf depths. Facies trends closely resemble across-shelf trends on the modern shelf, suggesting that processes were similar. Detailed examination of these deposits provides insight into the nature and role of various processes on both the ancient and modern shelf. Muddy facies of the Rio Dell sequence are characterized by bioturbated, clayey silts, interbedded with event layers of several types. Clay-rich silt layers are interpreted as flood deposits and physically stratified, coarse-silt layers are interpreted to record transport and deposition of coarse silt on the midshelf during storms. Sediment-transport calculations and consideration of grain-size distributions of bioturbated sediments, which form the bulk of the Rio Dell sequence, suggest that these sediments are the result of biological homogenization of the fine-grained flood deposits and of the coarser-grained storm deposits. The results of this study in general indicate that fine-grained shelf deposits do preserve a distinguishable, if subtle, record of depositional processes.     

天津滨海地区晚新生代地层自然固结与地面沉降研究

天津滨海地区地处渤海湾西岸,晚新生代沉积了巨厚的松散沉积物。地下水位下降、地层自然固结、地表载荷的加速增长等复合因素造成了严重的地面沉降。利用在天津滨海新区塘沽地区施工的一眼1 226 m全取芯钻孔,通过原状样品测试分析,系统研究了晚新生代土层的物理力学性质、黏性土固结特征,并结合欠固结黏性土层沉降量计算等方法阐述了土层固结状态空间特征,探讨了土层固结特征与地面沉降的相关关系。结果表明：该地区0～100 m深度土层具有低天然密度、高孔隙比、高含水率、高压缩性等特点,表现出软土的性质,在地表荷载增大的情况下,易发生地面沉降;100～550 m的黏性土大都处于超固结和微超固结状态,主要是由于过去地下水的大量开采造成的;550 m以下的黏性土多为正常固结,局部存在欠固结黏性土夹层。钻孔中存在合计约218 m的欠固结黏性土夹层,这些欠固结黏性土夹层在自重应力下的最终沉降量为1 985 mm,沉降量最大的土层对应于第1、6含水组,分别达614 mm和665 mm,这一沉降过程完成所需时间为数十年甚至上百年。     

Shift in detrital sedimentation in the eastern Bay of Bengal during the late Quaternary

Down-core variations of granulometric, geochemical and mineral magnetism of a 70-cm long sediment core retrieved from the eastern Bay of Bengal abyssal region were studied to understand sedimentation pattern and sediment provenance during the last ～12 kyr BP. Based on down-core physical and elemental variations, three units were identified: unit 3 (70–43 cm) is a ～30 cm thick clayey silt organic carbon-rich (0.5–0.92%) turbidite probably delivered by the Brahmaputra River during the late Quaternary period. Units 2 (43–24 cm) and 1 (24–0 cm) represent enhanced and reduced supply of coarse-grained detrital sediments from the Ganges River during early and late Holocene period, respectively. Increased terrigenous supply dilutes calcium carbonate (CaCO₃) and biogenic elements (P, Ba and Cu) in units 3 and 2. On the contrary, a reduction in detrital input enhances CaCO₃ and biogenic elements in unit 1. Lithogenic elements (Ti, Al, K and Rb) and shale-normalized REE patterns in all three units suggest terrigenous source. The shift in provenance from the Brahmaputra to the Ganges derived sediments is evident by a sharp increase in sediment grain size, increased concentration and grain size assemblages of magnetic minerals, lithogenic elements concentration and La_n/Yb_n ratio. This study highlights terrigenous dilution on biogenic sedimentation in the eastern Bay of Bengal sediments.     

The importance of changing oceanography in controlling late Quaternary carbonate sedimentation on a high-energy, tropical, oceanic ramp: north-western Australia

The North West Shelf is an ocean‐facing carbonate ramp that lies in a warm‐water setting adjacent to an arid hinterland of moderate to low relief. The sea floor is strongly affected by cyclonic storms, long‐period swells and large internal tides, resulting in preferentially accumulating coarse‐grained sediments. Circulation is dominated by the south‐flowing, low‐salinity Leeuwin Current, upwelling associated with the Indian Ocean Gyre, seaward‐flowing saline bottom waters generated by seasonal evaporation, and flashy fluvial discharge. Sediments are palimpsest, a variable mixture of relict, stranded and Holocene grains. Relict intraclasts, both skeletal and lithic, interpreted as having formed during sea‐level highstands of Marine Isotope Stages (MIS) 3 and 4, are now localized to the mid‐ramp. The most conspicuous stranded particles are ooids and peloids, which ¹⁴C dating shows formed at 15·4–12·7 Ka, in somewhat saline waters during initial stages of post‐Last Glacial Maximum (LGM) sea‐level rise. It appears that initiation of Leeuwin Current flow with its relatively less saline, but oceanic waters arrested ooid formation such that subsequent benthic Holocene sediment is principally biofragmental, with sedimentation localized to the inner ramp and a ridge of planktic foraminifera offshore. Inner‐ramp deposits are a mixture of heterozoan and photozoan elements. Depositional facies reflect episodic environmental perturbation by riverine‐derived sediments and nutrients, resulting in a mixed habitat of oligotrophic (coral reefs and large benthic foraminifera) and mesotrophic (macroalgae and bryozoans) indicators. Holocene mid‐ramp sediment is heterozoan in character, but sparse, most probably because of the periodic seaward flow of saline bottom waters generated by coastal evaporation. Holocene outer‐ramp sediment is mainly pelagic, veneering shallow‐water sediments of Marine Isotope Stage 2, including LGM deposits. Phosphate accumulations at ≈ 200 m water depth suggest periodic upwelling or Fe‐redox pumping, whereas enhanced near‐surface productivity, probably associated with the interaction between the Leeuwin Current and Indian Ocean surface water, results in a linear ridge of pelagic sediment at ≈ 140 m water depth. This ramp depositional system in an arid climate has important applications for the geological record: inner‐ramp sediments can contain important heterozoan elements, mid‐ramp sediments with bedforms created by internal tides can form in water depths exceeding 50 m, saline outflow can arrest or dramatically slow mid‐ramp sedimentation mimicking maximum flooding intervals, and outer‐ramp planktic productivity can generate locally important fine‐grained carbonate sediment bodies. Changing oceanography during sea‐level rise can profoundly affect sediment composition, sedimentation rate and packaging.     

天鹅洲长江故道湿地地下水砷的时空分布特征及控制机理

高砷地下水不仅直接危害供水安全,还可通过与湿地之间的交互作用,影响湿地水质进而威胁湿地生态安全.长江中游河湖平原已被报道广泛分布有高砷地下水,而位于长江中游故道区域的天鹅洲湿地地下水中砷的空间分布特征尚不明确,湿地与地下水的交互作用对地下水中砷季节性动态的控制机理尚不明确.本研究在天鹅洲湿地采集2个水文地质钻孔的35件沉积物样品、12个分层监测井不同季节的共72组地下水样和18组地表水样,通过水位-水化学监测、沉积物地球化学组成分析和砷、铁形态表征探究天鹅洲湿地地下水中砷的时空分布规律及控制机理.研究发现天鹅洲湿地地下水砷含量为1.08~147 μg/L,牛轭湖外侧浅井（10 m）地下水砷含量普遍高于深井（25 m）和牛轭湖内侧浅井（10 m）、深井（25 m）地下水,枯水期和平水期的砷含量高于丰水期.牛轭湖外侧浅层地下水系统具有更厚的粘土、亚粘土沉积,沉积物中总砷、强吸附态砷和易还原的铁氧化物的含量更多,吸附砷的水铁矿等无定形铁氧化物还原性溶解导致砷释放进入地下水中.枯水期天鹅洲湿地底部向牛轭湖外侧浅层含水层输送不稳定的有机质,使天鹅洲湿地地下水-地表水界面成为砷释放的热点区域.丰水期时牛轭湖外侧含水层受长江补给的影响,还原环境发生改变使地下水中的砷和铁被氧化固定从而不利于砷向地下水释放.      

Metals in the sediments of Ensenada de San Simón (inner Rı́a de Vigo), Galicia,NW Spain

The Ensenada de San Simón is the inner part of the Rı́a de Vigo, one of the major mesotidal rı́as of the Galician coast, NW Spain. The geochemistry of its surface sediments, and the river sediments which drain into it from a granitic and metamorphic hinterland, are described. Multivariate statistical analysis of the sediment compositions (using ridge regression and mixture-modelling) enabled the major- and trace-element distributions to be accounted for in terms of both natural and anthropogenic sources: Between 60 and 80% of the Cr, Cu, Ni, Pb and Zn concentrations of the bottom sediments of the Ensenada can be explained by sediment input from the combined R. Oitaben and R. Verdugo, the R. Redondela and faecal matter from mussel rafts, but there is additional enrichment towards the mouth of the Ensenada. This enrichment is attributed to marine water entering the Ensenada from the polluted industrial areas of the adjacent Rı́a de Vigo. It is suggested that these metals are carried landwards in solution by the tidal incursion of marine water (the volume of which, on an annual basis, greatly exceeds that contributed by the rivers). Although the incoming marine waters may also be important in supplying Pb to the outer Ensenada, this element may also be delivered by land run-off, or by windborne vehicular emissions to the Ensenada as a result of the surrounding network of roads and a road bridge over the Estrecho de Rande.     

Changing depositional environment revealed from sediment components,west of “Swatch of No Ground”, northern Bay of Bengal

The sediment cores of 20 cm length collected from 31 to 83 m range of water depth from the inner shelf of Bay of Bengal west of “Swatch of No Ground” were analyzed for grain size, organic carbon, total nitrogen, calcium carbonate and clay mineralogy. Grain size analysis revealed that the sediment size decreases from west to east within the study area indicating a possible direction of transport towards east parallel to the coast. The grain size also decreases with increasing water depth, i.e. north to south, indicating sediment contribution to the area of study from Hooghly and other local rivers. In the cores studied, illite was the dominant clay mineral which seems to be a product of glacial weathering under arid conditions with its source being the Himalayan region. The organic carbon content was low in the sediments and was attributed to low plankton production or intense oxidation processes. Low calcium carbonate percentage also supports the view of a low productivity in this region. Organic carbon increases gradually from west to east indicating its association with finer sediments and also indicates transport due to currents which drift the organic carbon away before it settles down within the sediments. Higher values relatively closer to the coast in the eastern side indicate additional contribution from Sunderban mangroves. The C/N ratio obtained indicates mixed source of terrestrial and marine for the organic matter in the sediments. Sedimentation rates available for deltaic plains and shelves off Bangladesh when adopted for the present area revealed that a 20 cm long sediment column was deposited in around 10 years. In most of the cores studied, a change in the trend of sediment components and organic carbon was observed at around 10 cm where grain size increases and organic carbon decreases towards the surface inferring that during the last 5 years, possible floods during NE monsoon or due to melting of ice in Himalaya are responsible for releasing additional water and material which brought a change in hydrodynamic conditions. The surface depletion of organic carbon indicates its dilution by the addition of coarser materials.     

Environmental geochemistry of the Pichavaram mangrove ecosystem (tropical), southeast coast of India

 Spatial and temporal geochemical variations of various parameters in the water and sediment of a relatively small mangrove situated on the southeast coast of India were examined in detail for the first time. The water quality generally reflects the impact of seawater and the Vellar estuary (mixing effect) aided by evaporation and in situ biological productivity. The depletion and fluctuation of dissolved silica are controlled by biological processes. Nitrate and phosphate are contributed by fertilizer input from adjoining agriculture fields. Total suspended matter (TSM) shows an erratic range and trend due to deforestation and resuspension processes. Sand and silt constitute 70–90% of the sediments. Statistical analysis of the sediments shows the prevalence of a moderately high-energy environment with very effective winnowing activity. Organic matter content is higher in the mangrove sediments in comparison to adjacent estuaries. Water and sediment show fluctuations in their chemical concentration, but no specific trends could be identified. Heavy metals are also enriched in the mangrove sediments, indicating their unique chemical behavior and the existence of trapping mechanisms. Factor analysis and correlation analysis of water and sediments show the complexity of the system and the multitude of contributing sources. The core sediment chemistry suggests the depletion of metal input due to the damming of the detrital inputs. The Pichavaram mangrove seems to be relatively unpolluted, since the anthropogenic signal observed is small and acts as a sink for heavy metals contributed from a multitude of sources without an adverse effect. Received: 5 November 1997 · Accepted: 30 March 1998     

东海陆架泥质沉积物中固相Fe形态及其对有机质、Fe、S成岩路径的制约意义

利用化学提取法对中国东海具有不同陆源物质的内陆架(0701)和外陆架(0508)泥质沉积物柱样进行的多种形态固相铁含量及其剖面分布研究结果表明,Fe形态及其分布对有机质、Fe和S早期成岩作用具有明显的制约意义.0508和0701两站点柱状沉积物总活性Fe平均含量分别为12.14 mg/g和10.03 mg/g,其中,氧...