全安盆地水文地质特征及热水成因分析

在简要分析全安盆地水文地质特征、地下水赋存条件及划分地下水类型基础上,对盆地西部周地—暖水塘地区地下热水形成原因、赋存环境进行研究,认为多期次构造运动形成的断裂、裂隙沟通深部地下热水是盆地热水来源的主要原因;采取地下热水样品并开展氢氧稳定同位素、逸出气体、水化学成份测试,认为地下热水由大气降水补给,长期水动态观测结果也显示大气降水与地下热水关系较密切。     

羊八井地热田水文地球化学特征

西藏羊八井地热田热流体化学成分主要是以氯化钠为主的地下热水.在地热田未开采的深部,地热流体是处于高温高压过饱和的液相状态,其中溶解有大量的CO_2、H_2S等气体.当地热流体从地下深部往地表上升过程中,由于压力、温度迅速降低,地热流体变成了三相,详见表1.液相—流出井口的地下热水或出露地表的温泉水;气相—溶解气体因压力降低而     

山东德州凹陷地下热水地球化学特征及成因

典型地区地下水成因和演化机制的研究不仅对于热水资源的合理利用与开发具有重要的指导意义,而且可以为日后的地热资源勘查评价提供重要信息。笔者通过对德州凹陷的地下热水的化学成分、同位素及其水文地质特征的分析,进而对这一地区的地下热水的成岩和演化过程进行了研究。结果显示地下热水的形成受区内深大断裂和基底构造对地热形成的控制,地下热水补给是来自大气降水,为入渗变质水,水化学成分以易溶盐溶解作用为主,其气体组分主要起源于大气、地壳和地幔的混合物,反映了地下水长期径流及深循环中各种水化学作用。     

渭南市地下热水水化学形成作用研究

通过对渭南地下热水水化学特征的分析,对比研究不同水化学成分之间的关系,结合研究区岩性及矿物性质,全面的分析了各热水样所经历的各种水化学作用及主控作用.研究表明:渭南不同区域地下热水水化学类型存在较大差异,不同水样所经历的水化学作用亦差别较大,除经历不同程度的溶滤作用与阳离子交替作用外各具特征,指示地下热水赋存环境存在较...     

河北廊坊南部地区地热水化学特征及成因机制

地热资源的开发利用带来了良好的经济效益和社会价值,但不合理地开发利用地热资源,会对地表水及浅层地下水造成重大污染。通过水化学分析和水文地球化学模拟手段,分析了廊坊南部地区地下热水水化学特征及水质的成因机制。研究表明：新近系孔隙热储中,明化镇组热储地下热水主要水化学类型为HCO₃-Na型、HCO₃·Cl-Na型;馆陶组热储地下热水水化学类型以Cl-Na型、Cl·HCO₃-Na型为主,该层水力联系较好,地热水径流区内主要水岩作用为硫酸盐、硅酸盐矿物的溶解作用,以及阳离子交替吸附作用。基岩裂隙热储地下热水水化学类型为Cl-Na型,该层水力联系较弱,阳离子交替吸附作用是水化学演化的主要水岩相互作用。基于PHREEQC的水文地球化学定量模拟,揭示了地质背景、水文地质条件及人类活动因素共同控制的地下热水的流场和水岩相互作用的程度,在研究廊坊地区地热水水化学演化机理及地热水动态特征方面具有一定的意义。     

聊城市东部岩溶地热田地下热水水化学特征及成因分析

通过对聊城市东部岩溶地热田的地下热水的化学成分、同位素及其水文地质特征的分析,对这一地区的地下热水的形成和演化过程进行了研究。结果显示地下热水的形成受区内深大断裂和基底构造的控制。本区地下热水的形成是在漫长的地质历史发展过程中各种自然因素综合作用的结果。δD和δ18O的关系及氚（T）值和水化学特征系数说明地下热水为近代大气降水入渗起源的中度或高度变质水,以40年前的古水占优势,新近入渗水的补给量较小。水化学成分的形成以溶滤、溶解作用为主,微量元素成分丰富,反映了地下水经过了漫长和复杂的径流及深循环过程。      

山东莘县凹陷（聊城段）地下热水化学特征及成因

典型地区地下水成因和演化机制的研究不仅对于热水资源的合理利用与开发具有重要的指导意义,而且可以为日后的地热资源勘查评价提供重要信息。通过对莘县凹陷聊城段的地下热水的化学成分、同位素及其水文地质特征的分析,进而对这一地区的地下热水的成岩和演化过程进行了研究。地下热水的形成受区内深大断裂和基底构造对地热形成的控制,地下热水补给是来自大气降水,为入渗变质水,水化学成分以易溶盐溶解作用为主,反映了地下水长期径流及深循环中各种水化学作用。     

因子分析法在深层地下热水水化学组分形成作用中的应用

地下热水水质是地下热水的重要特征之一,也是地下热水资源评价的主要内容,其为制定地下热水合理开发利用方案提供重要依据。研究地下热水水化学组分形成作用一直是国内外水文地球化学的研究重点。利用R型因子分析法对咸阳市区地下热水水样的水化学数据进行分析,分析研究可知:咸阳市区南部热水起源成因复杂,水化学成分多样HCO3·SO4-Na、Cl·SO4-Na型为主。北部热流体水化学类型主要为Cl-Na型,纵向上随深度增加基本不变化,其主要发生的水化学形成作用有溶滤作用和脱硫酸作用,次为阳离子交替吸附、脱碳酸作用和石膏的溶解作用。     

柴北缘大柴旦地区地下热水成因：来自水化学及氢、氧、锶同位素的约束

为探究柴达木盆地北缘的大柴旦地热田的水化学特征及成因模式,本文对研究区14组地下热水进行了水化学组分和同位素(δD,δ¹⁸O,⁸⁷Sr/⁸⁶Sr,³H)分析。结果表明,大柴旦地下热水出露温度为52～74℃,溶解性总固体浓度(TDS)为959.8～1451.3 mg/L。地下热水的水化学类型为Cl-Na型,区内地下热水的水化学成分主要来源于蒸发岩和硅酸盐矿物的溶解;氢、氧稳定同位素特征表明,大气降水及冰雪融水是地下热水主要补给来源,且部分温泉有岩浆水的补给,估算的补给高程为3591～4374 m。³H测年结果表明,区内地下热水主要由1952年之前的古水补给、蒸发作用和水-岩反应增强导致。XSWQ-06和XSWQ-07样品有明显的氧漂移。基于SiO₂地热温标、多矿物平衡法和硅焓模型估算出的地下热水的热储温度为171～227℃,循环深度为4.7～6.9 km。该地区地热资源具有较大的开发利用潜力。     

西安凹陷热储流体环境同位素研究

为了了解西安凹陷地下热水的补给循环及其赋存环境特征,对西安凹陷地下热水D、^18O、^13C、^14C、^34S分布特征进行了测定与分析。研究表明：西安城区地下热水中环境同位素δ（^180）、δ（^13C）、δ（^34S）的分布规律与其所在的关中盆地存在相反趋势,指示西安城区地下深部存在欠压实作用,表明西安是一个年轻的快速沉积盆地或其深部存在开启性断裂。通过水化学分析表明西安地区主要水化学类型为SO4-Na型,咸阳主要为Cl—Na型,指示咸阳地区的地质环境更为封闭。根据补给高程计算,西安、咸阳城区地下热水补给来源分别为秦岭和北山末次冰期高山雪水补给。     

Comparative urbanization in Ghana and Kenya in time and space

There are few inter-African country urban analyses because of the continent’s enormous size and socioeconomic diversity, language barriers, and wide variations in national and regional urban research capacity. Nevertheless, comparative urban studies are critical in understanding contemporary African urbanization. In this comparative spatial and temporal analysis of Ghana and Kenya’s urbanization, we find that both countries are urbanizing rapidly and are faced with many common urban problems. Moreover, Ghana is more urbanized than Kenya and has a larger indigenous urban imprint and a more widely dispersed urban pattern. Besides their physiographic and population conditions, we trace these countries’ convergent and divergent urban trends to their shared but unique experiences of colonialism, nationalism and globalization.     

Hydrogen and carbon in solid solution in oxides and silicates

The dissolution of H₂O and CO₂ in structurally dense, nominally anhydrous and non-carbonate oxide matrices such as MgO and CaO is reviewed. H₂O and CO₂ are treated as gaseous oxide components which enter into solid solution with the refractory oxide hosts. They form anion complexes associated with cation vacancy sites. Evidence is presented that OH^? pairs which derive from the dissolution of H₂O are subject to a charge transfer (CT) conversion into peroxy moieties and molecular hydrogen, O ₂ ^2? ... H₂. Because the O ₂ ^2? moiety is small (O^?-O^? distance ≈ 1.5 Å) high pressure probably favors the CT conversion. Mass spectroscopic studies show that molecular H₂ may be lost from the solid which retains excess oxygen in the form of O ₂ ^2? , leading to the release of atomic O. The dissociation of O ₂ ^2? moieties into a vacancy-bound O^? state and an unbound O^? state can be followed by measuring the internal redox reactions involving transition metal impurities, the transient paramagnetism of the O^? and their effect on the d.c. conductivity. Evidence is presented that CO₂ molecules dissolve dissociatively in the structurally dense oxide matrix, as if they were first to dissociate into CO+O and then to form separate solute moieties CO ₂ ^2? and O ₂ ^2? , both associated with cation vacancy sites. In the CO ₂ ^2? moiety (C-O^? distance 1.2–1.3 Å, OCO angle ≈ 130°) the C atom probably sits off center. The transition of the C atom into interstitial sites is accompanied by dissociation of the CO ₂ ^2? moiety into CO^? and O^?. This transition can be followed by infrared spectroscopy, using OH^? as local probes. Further support derives from magnetic susceptibility, thermal expansion, low frequency dielectric loss and low temperature deformation measurements. The recently observed emission of O and Mg atoms besides a variety of molecules such as CO, CO₂, CH₄, HCN and other hydrocarbons during impact fracture of MgO single crystals is presented and discussed in the light of the other experimental data.     

岩溶地区现代土壤与洞穴石笋中单甲基支链烷烃与烷基环己烷对比研究

利用GC-MS（气相色谱—质谱仪）,对采自湖北清江流域和尚洞洞顶的土壤样品与洞内石笋样品进行分析,发现土壤中存在的七个系列单甲基支链烷烃在所有的石笋样品中均可以找到,呈现相似的分布模式,石笋中七个系列支链烷烃有可能来自洞穴滴水携带的土壤中的支链烷烃,但是也不能排除石笋原地生长的微生物的贡献。烷基环己烷的分布在土壤与石笋中呈现了相似的分布模式,但是主峰碳数有所变化,高碳数部分与低碳数部分的相对含量也发生了变化。主要原因可能是微生物选择性降解的结果,也有可能是土壤与石笋中微生物种类分布差异所造成的。本次研究初步显示了相对封闭稳定的洞穴沉积物与上覆土壤层中生物标志化合物的异同。      

Re-Os and Pd-Ag systematics in Group IIIAB irons and in pallasites

Using improved analytical techniques, which reduce the Re blanks by factors of 8 to 10, we report new Re-Os data on low Re and low PGE pallasites (PAL-anom) and IIIAB irons. The new pallasite samples nearly double the observed range in Re/Os for pallasites and allow the determination of an isochron of slope 0.0775 ± 0.0008 (T = 4.50 ± 0.04 Ga, using the adjusted λ¹⁸⁷Re = 1.66 × 10⁻¹¹ a⁻¹) and initial (¹⁸⁷Os/¹⁸⁸Os)₀ = 0.09599 ± 0.00046. If the data on different groups of pallasites (including the “anomalous” pallasites) are considered to define a whole-rock isochron, their formation would appear to be distinctly younger than for the iron meteorites by ∼60 Ma. Five IIIAB irons (Acuna, Bella Roca, Chupaderos, Grant, and Bear Creek), with Re contents ranging from 0.9 to 2.8 ppb, show limited Re/Os fractionation and plot within errors on the IIAB iron meteorite isochron of slope 0.07848 ± 0.00018 (T = 4.56 ± 0.01 Ga) and initial (¹⁸⁷Os/¹⁸⁸Os)₀ = 0.09563 ± 0.00011. Many of the meteorites were analyzed also for Pd-Ag and show ¹⁰⁷Ag enrichments correlated with Pd/Ag, requiring early formation and fractionation of the FeNi metal, in a narrow time interval, after injection of live ¹⁰⁷Pd (t_1/2 = 6.5 Ma) into the solar nebula. Based on Pd-Ag, the typical range in relative ages of these meteorites is ≤10 Ma. The Pd-Ag results suggest early formation and preservation of the ¹⁰⁷Pd-¹⁰⁷Ag systematics, both for IIIAB irons and for pallasites, while the younger Re-Os apparent age for pallasites suggests that the Re-Os system in pallasites was subject to re-equilibration. The low Re and low PGE pallasites show significant Re/Os fractionation (higher Re/Os) as the Re and PGE contents decrease. By contrast, the IIIAB irons show a restricted range in Re/Os, even for samples with extremely low Re and PGE contents. There is a good correlation of Re and Ir contents. The correlation of Re and Os contents for IIIAB irons shows a similar complex pattern as observed for IIAB irons (Morgan et al., 1995), and neither can be ascribed to a continuous fractional crystallization process with uniform solid-metal/liquid-metal distribution coefficients.     

Geogenic and anthropogenic zinc in epiphytic and terricolous lichens in Finland

At 31 sites in Finland the Zn content was determined of the epiphytic lichen Hypogymnia physodes (L.) Nyl. growing on pine and birch, the terricolous lichen Cladina spp. in pine bark, and the inner part of birch bark. The anomalous contents of Zn in H. physodes on pine and Cladina spp. in soil appeared to be strongly related to sulphide ore deposits. Anthropogenic Zn correlated closely with S and Fe in H. physodes on pine and with Fe in Cladina spp. The binding of geogenic Zn was related to iron hydroxides, and was attributed to the different uptake mechanism of S in these lichens. Elevated values of Zn in H. physodes on birch were due to both geogenic and anthropogenic sources. Zinc in pine bark increased with the Zn content in H. physodes and reached a limiting value.     

煤中气孔和镶嵌结构及其在煤变质研究中的意义

河南省禹县、新密和荥巩煤田山西组Ⅱ₁煤的贫煤和无烟煤中,气孔发育。气孔形态有椭圆状（图版1）、圆状及不规则状（图版2）,有的几个气孔连在一起呈大的朵状气孔(图版3)。此外,在荥巩煤田西部无烟煤中还发育有镀嵌结构(图版4)。      

Amphibole and chlorite in mafic and ultramafic rocks in the lower crust and upper mantle

Stabilities of amphibole and chlorite in mafic and ultramafic compositions have been considered in the model system CaO+MgO+Al₂O₃+SiO₂+H₂O. From topological arguments two petrogenetic grids have been constructed. Although available experimental data in CMASH are compatible with the grid in which amphibole reacts out before chlorite in model ultramafic compositions for the pressure range 6 to 15 kbar, naturally observed mineral assemblages and some experimental data in more complex systems favour the other grid in which chlorite reacts out before amphibole at all pressures. This discrepancy between natural and model systems is due to differential movement of the dehydration equilibria of the two hydrates reflecting the variation of activity of H₂O or of components other than CMASH.     

Water-extractable and exchangeable phosphate in Martian and carbonaceous chondrite meteorites and in planetary soil analogs

Aqueous extraction contributes to the formation and weathering of planetary materials and renders electrolytes such as phosphate available for biology. In this context, the solubility of phosphate is measured in planetary materials, represented by the Mars meteorites Nakhla, Dar al Gani 476 (DaG 476), Elephant Morraine 79001 (EETA 79001), and terrestrial analogs, and in the Murchison CM2 and Allende CV3 carbonaceous chondrites. The Mars meteorites contain high levels of phosphate that is readily extracted by water, up to 15 mg kg⁻¹ in Nakhla and DaG 476 and 38 mg kg⁻¹ in EETA 79001, while the terrestrial analogs and the carbonaceous chondrites contain 0.5 to 6 mg kg⁻¹. Correspondingly, high phosphate concentrations of 4 to >28 mg L⁻¹ are obtained in extracts of the Mars meteorites at high solid/solution ratios, exceeding the concentrations of 0.4 to 2.0 mg L⁻¹ in the extracts of the terrestrial analogs. A wide range of planetary conditions, including N₂ and CO₂ atmospheres, solid/solution ratios of 0.01 to 1.0 kg L⁻¹, extraction times of 1 to 21 d, and temperatures of 20 to 121°C affect the amounts of extractable phosphate by factors of only 2 to 5 in most materials. Phosphate-fixing capacity and exchangeable phosphate are assessed by the isotopic exchange kinetics (IEK) method, which quantifies the amount of P isotopically exchangeable within 1 min (E_1min) and between 1 min and 3 months (E_1min-3m) and the amount of P that cannot be exchanged within 3 months (E_>3m). The IEK results show that the DaG 476 Mars meteorite and terrestrial analogs have low P-fixing capacities, while the carbonaceous chondrites have high P-fixing capacities. Aqueous processing under early planetary CO₂ atmospheres has large effects on the available phosphate. For example, the fraction of total P that is exchangeable in 3 months increases from 1.6 to 11%, 13 to 51.6%, and 43.9 to 90.4% in the DaG 476 Mars meteorite, Allende, and Murchison, respectively. The results show that solutions with high phosphate concentrations can form in the pores of planetary lava ash and basalts and in carbonaceous asteroids and meteorites. These solutions can help prebiotic synthesis and early microbial nutrition. The Martian and carbonaceous chondrite materials contain sufficient phosphate for space-based agriculture.     

Discovery of Cinnabar in Soils in Hg Anomalous Zones in City and Town Areas and Their Surroundings and Its Significance

As a result of systematic study on heavy minerals in soils at city and town areas and their surroundings,cinnabar was discovered for the first time in areas of Hg anomalies in China, and it was found that the distribution of cinnabar was basically coincident in scope with that of Hg anomalies, showing that Hg anomalies were‘closely related to cinnabar. This finding provides a theoretical basis for a verification of Hg anomalies in soils in city and town areas and their surroundings, as well as evaluation of its ecological effects, and is significant to revealing the occurrence modes and origin of Hg in soils.     

Temporal and spatial variations in water discharge and sediment load in the Alaknanda and Bhagirathi Rivers in Himalaya, India

The Alaknanda and Bhagirathi Rivers originate in the mountainous regions of the Himalayas (Garhwal) and result in high sediment yields causing flood hazards downstream of the Ganga River and high sediment flux to the Bay of Bengal. The rivers are perennial, since runoff in these rivers is controlled by both precipitation and glacial melt. In the present study, three locations in the upper reaches of the Ganga River were monitored for 1 yr (daily observations of, more than >1000 samples) for suspended sediment concentrations. In addition, more than one hundred samples were collected from various locations of the Alaknanda and Bhagirathi Rivers at different periods to observe spatial and temporal variations in river suspensions. Further, multi-annual data (up to 40 yrs) of water flow and sediment concentrations were used for inferring the variations in water flow and sediment loads on longer time scales. In most previous studies of Himalayan Rivers, there has been a general lack of long term water flow and sediment load data. In the present study, we carried out high frequency sampling, considered long term discharge data and based on these information, discussed the temporal and spatial variations in water discharge and sediment loads in the rivers in the Himalayan region. The results show that, >75% of annual sediment loads are transported during the monsoon season (June through September). The annual physical weathering rates in the Alaknanda and Bhagirathi River basins at Devprayag are estimated to be 863 tons km⁻² yr⁻¹ (3.25 mm yr⁻¹) and 907 tons km⁻² yr⁻¹ (3.42 mm yr⁻¹) respectively, which are far in excess of the global average of 156 tons km⁻² yr⁻¹ (0.58 mm yr⁻¹).