云南点苍山冰川湖泊沉积物磁化率的影响因素及其环境意义

文章通过对点苍山海拔3820m冰水沉积剖面的粒度参数、磁化率、氧化铁含量和有机质含量的综合实验分析,并讨论了这些指标的相互关系及其环境意义。实验结果表明,磁化率的强度与粗砂组分的含量成正相关,而与粘土等细粒组分含量成负相关;同时与有机质含量成负相关,与氧化铁含量成正相关。矿物组分分析实验表明,沉积物主要磁性来源于磁化铁。根据以上结果,结合冰川湖泊流域面积小、高寒环境的特点,其磁化率的影响因素与一般湖泊不同,认为冰川湖泊沉积中,因为物源较近导致外源磁性矿物主要赋存于粒度较粗的碎屑颗粒中,而高寒的环境条件使得有机质对沉积物的磁性矿物起到了稀释的作用,而很难有积极的贡献。根据磁化率的环境意义,恢复了全新世以来点苍山的古气候,从中可以划分6个不同的气候阶段:11.5～10.6kaB.P.,10.6～8.9kaB.P.,8.9～5.5kaB.P.,5.5～3.3kaB.P.,3.3～0.8kaB.P.和0.8kaB.P.至今,代表了末次冰期结束以后湖泊从产生至消亡的全过程。根据与其他相关地区的对比,分析了西南季风演变的一些规律。     

油气资源预测统计模型及其应用

松辽盆地北部的油气勘探程度虽然较高,但仍然有一些尚未发现的油气资源。本文在对预测油气资源的分形分布模型和截断帕雷托(TSP)分布模型两种统计模型进行系统研究的基础上,结合油气藏地质规律,通过预测该区未发现的油(气)田数量及其储量规模分布,认为方法可行,结果供参考,并待实践进一步验证。得出主要结论是:分形分布模型是一种预测油气田数量和储量(资源量)的可靠方法,在勘探程度较高的盆地或区带应用效果较好,而在勘探新区应用则有一定难度;截断帕雷托分布模型相对于分形分布模型不很完善,但应用该模型进行油气资源分布预测受具体盆地地质条件的影响较小,具有应用价值。     

The distribution, sources and toxicity risks of polycyclic aromatic hydrocarbons and n-alkanes in riverine and estuarine core sediments from the Daliao River watershed

The burial characteristics and toxicity risks associated with n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in the riverine and estuarine sediments of the Daliao River watershed were investigated based on three sediment cores. The sum of the n-alkane and PAH concentrations, normalized to organic carbon (OC), ranged from 0.27 to 63.09 μg g^?1OC^?1 and 6.60 to 366.20 μg g^?1OC^?1, respectively. The features and the history of industrial activities, such as the oil and chemical industries and port activities near the river and estuary, resulted in different distributions and sources of hydrocarbons. The sources of pollution were identified based on n-alkane indexes and on diagnostic ratios of PAHs. The diagnostic ratios indicated that the n-alkanes were derived from both biogenic and petrogenic sources in different proportions and that the PAHs were derived primarily from petrogenic combustion sources. A hierarchical cluster analysis grouped the core samples into two clusters. The first cluster, river sediments, corresponded to industrial activities; the second cluster, estuarine sediments, corresponded to port shipping activities. The toxic potency of the PAHs in the cores was assessed in terms of toxic equivalents (TEQs) of dibenzo[a,h]anthracene and benzo[a]pyrene. The top layer of the sediment in the cores had a relatively high toxicity. The TEQ values for benzo(a)pyrene (TEQ_BaP) and dioxins (TEQ_TCDD) furnished a consistent assessment of the PAHs in the sediment cores.     

河北省灵寿县西石门金矿黄铁矿热电性标型及其找矿意义

河北省灵寿县西石门石英脉型金矿位于华北地台太行隆起区之南东部的阜平矿集区,与该区石湖大型金矿受不同断裂控制。黄铁矿是矿床的主要载金矿物,以4个世代产出于黄铁矿-石英阶段(I)、石英-黄铁矿阶段(II)、多金属硫化物阶段(III)和石英-碳酸盐阶段(IV)等4个成矿阶段,其中,石英-碳酸盐阶段的黄铁矿十分稀少。本矿段黄铁矿单晶热电系数变化范围为-328~341μV/℃,从早期到晚期,4个世代的黄铁矿热电系数离散性先增大再减小,石英黄铁矿阶段（II）离散性最大。从黄铁矿-石英阶段(I)至石英-碳酸盐阶段(IV),黄铁矿热电导型的变化规律是P>N(III)→P>>N (IV); P型黄铁矿热电系数均值αP和出现率P%由浅部到深部,总体为逐渐降低,局部呈波状起伏,与矿石金品位呈正相关关系.黄铁矿的热电系数温标计算和投图表明,该矿床的成矿温度集中在168～330℃,为中低温矿床。热电系数在50—200μV/℃之间的黄铁矿是富金矿段的标志。综合分析认为,该矿床290m以下仍有良好的找矿潜力。     

高压力下原状层间错动带三轴不排水剪切特性及其影响因素分析

针对某大型水电站揭露的原状层间错动带试样,模拟现场快速施工可能会产生的不排水边界条件,在围压5～30 MPa的高压力条件下开展了不固结不排水三轴试验,并结合试样物理性质的差异,分析讨论了原状层间错动带的力学特性。试样试验曲线和破坏模式主要由高围压控制：其应力-应变关系曲线均为应变硬化型且破坏后呈腰鼓状为塑性破坏。此外,较湿颗粒发生了大规模的颗粒破碎,其是造成高饱和度试样强度包线的趋势线随围压降低的根本原因。试验结果明显受物理性质影响造成了试验数据离散性,敏感性分析表明,围压P和饱和度 对初始弹性模量 和破坏强度 的影响最大,其次是孔隙比e,颗粒粒径（ ）分布对其影响程度最小。根据试样剪切特性建立的强度特征（ 和 ）初步预测公式可供实际工程参考。     

宁夏吴忠市金积水源地地下水水质影响因素的多元统计分析

根据吴忠市金积水源地地下水饮用水用途选择11项水化学指标,采集32个地下水水样进行测试分析及处理。在分析金积水源地地下水流场及水化学特征基础上,综合利用因子分析法和系统聚类分析方法对水质影响因素进行评价,2种方法评价结果基本一致。结果表明,该区地下水水质影响因素主要有：以Cl^-、SO^2-₄、Mg²⁺、NO^-₃、Ca²⁺质量浓度为代表变量的溶滤作用,该作用表现为西强东弱,综合主成分贡献率48.40%;以EC、总硬度及TDS、Na⁺、HCO^-质量浓度为代表变量的蒸发浓缩作用,沿补给区和排泄区作用较强,综合主成分贡献率39.66%;以NH₄-N质量浓度为主要载荷变量的人类活动影响因素,因子得分较高区域与企业分布及排污范围分布一致,综合主成分贡献率11.94%。水质影响因素分布总体表现为黄河沿岸蒸发浓缩作用相对较强;汉渠以北主要受溶滤作用及地下水蒸发浓缩共同影响;南干沟及南干沟入黄河口附近氨氮污染较明显。     

海河流域严重干旱500hPa信号场异常信号分析

基于严重少雨旬的定义,分析海河流域1961～2009年严重少雨旬的分布特征,进而对汛期40个典型严重少雨旬的500hPa信号场进行经验正交分解(EOF分析).结果表明:EOF第一模态的方差贡献率达到35.3％,远高于其他模态;第一模态呈现出2个负异常区和1个正异常区,在对应的环流背景下,海河流域受暖性高压控制,高纬冷空气及低纬暖湿气流难以到达流域上空交绥,持续高温少雨造成流域严重干旱.     

Investigation of manganese tolerance and accumulation of two Mn hyperaccumulators Phytolacca americana L. and Polygonum hydropiper L. in the real Mn-contaminated soils near a manganese mine

Up to date, very few studies have examined the phytoextraction ability of hyperaccumulators in the real soils contaminated with heavy metals following the identification of the hyperaccumulators using hydroponics tests. In the present study, amended with a chemical-mobilizing agent of ethylene diamine triacetic acid (EDTA), the manganese accumulation, tolerance and the hyperaccumulating ability of two hyperaccumulators Phytolacca americana L. (Phytolaccaceae) and Polygonum hydropiper L. (Polygonaceae) proved by previous hydroponics tests were examined using pot experiments with paddy soils contaminated with Mn (1,047 ± 53 mg kg^?1) collected from one site in the vicinity of one manganese mine in Xiushan county of Chongqing, China. Results showed that the root and shoot biomass of P. americana and the chlorophyll production of P. hydropiper were significantly inhibited by EDTA treatments while the chlorophyll production of P. americana was oppositely obviously promoted by EDTA. It is noteworthy that, with or without EDTA treatment, the shoot Mn concentrations of both plant species were significantly below the hyperaccumulator threshold, indicating these two plants concealed their hyperaccumulating ability in the studied soils. Thus, further detailed studies need to be conducted to promote the metal hyperaccumulating capacity of these two plant species under comparably low Mn-contaminated soil conditions as shown in this study before the successful application of these Mn hyperaccumulators identified in laboratories to the phytoextraction of lightly or moderately Mn-contaminated agricultural soils.     

High-resolution profiles of iron, manganese, cobalt, cadmium, copper and zinc in the pore water of estuarine sediment

The remobilization of iron, manganese, cobalt, cadmium, copper and zinc in the pore water of estuarine sediment cores at Yingkou was assessed using diffusive equilibrium in thin films and diffusive gradients in thin films techniques. A relatively anoxic system (+33.7 to ?224.1 mV) in the sediment cores might cause the reductive release of iron, manganese and cobalt into pore water from the estuarine sediment. High-average concentrations of iron (47.85 μg ml^?1) and manganese (3.81 μg ml^?1) were observed using diffusive equilibrium in thin films on the sediment core, but the concentration of cobalt (18.02 ng ml^?1) was relatively low. A strong correlation between iron and cobalt was observed based on the vertical profiles of the metals. Manganese and iron were more readily released from the solid phase to the solution. The peak cobalt, copper and zinc concentrations were observed in the upper layer (2–4 cm) measured using diffusive gradients in thin films. However, the peak iron, manganese and cobalt concentrations were located in the deeper layer (≥7 cm). In addition, the concentration profiles measured using diffusive gradients in thin films of cobalt, copper and zinc were independent of the iron, manganese and cobalt distribution with respect to depth.     

松辽盆地榆树林油田下白垩统泉头组扶余油层浅水三角洲沉积特征及其演化

松辽盆地榆树林油田下白垩统泉头组四段扶余油层沉积时期发育大型浅水三角洲沉积。本文基于12 口探井岩心与
2268 口钻井资料,通过单井岩心相分析、测井相分析、连井相对比和平面沉积微相研究,认为研究区发育浅水三角洲平原、
内前缘、外前缘和前三角洲亚相,以浅水三角洲平原亚相为主,平原分流河道和内前缘水下分流河道为主要沉积微相。在
扶三段（F Ⅲ）早期,研究区主要为浅水三角洲内前缘亚相,物源只来自北部 ;其后,三角洲向南进积,全区变为平原亚
相 ;F Ⅲ 3 小层沉积时期,南部物源进入,并与北部物源交汇,一直持续至扶一段（F Ⅰ）末期;在 F Ⅰ 3 小层沉积末期,湖
平面快速上升,南北两个三角洲退积,研究区中部依次出现浅水三角洲内前缘、外前缘和前三角洲。