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81.
Seasonal variations of adsorption/desorption equilibrium were investigated by collecting overlying water and seasonal sediment from the Meiliang Bay, Taihu Lake, China. At the same time, seasonal variations of TP and P fractions' concentrations in the initial and end of adsorption experiment were also carried out. In addition, the effects of temperature on the P translocation process were also conducted and discussed. The following conclusions were obtained: The sequence of adsorption/desorption equilibrium concentrations of P at water-sediment interface was spring〈winter〈autumn. In sediment the concentrations of TP decline. Concentration P decreased with temperature.  相似文献   
82.
氟铝交互作用对茶园土壤氟吸附动力学特征的影响   总被引:1,自引:0,他引:1  
在氟的不同初始浓度及不同水土比情况下,茶园土壤对氟的吸附平衡时间均在25min左右,但对动力学方程拟合效果有一定差异,除了初始浓度为4.0mg/L(水土比10∶1)、20.0mg/L(水土比40∶1)、100.0mg/L(水土比40∶1和20∶1)处理氟的吸附动力学不能用一级动力学方程或二级动力学方程描述外,其余处理均可以用双常数方程、Elovich方程、一级动力学方程、二级动力学方程和抛物线方程这5个动力学方程描述。在铝存在下,不同氟铝比对氟的吸附动力学过程有明显影响,表现为吸附速率下降,吸附平衡时间延长,50min左右达吸附平衡。动力学方程拟合效果虽然有一定差异,但均可以用这5个动力学方程描述。在有无铝存在下,茶园土壤氟的吸附动力学特征用双常数方程和Elovich方程描述的效果更好。  相似文献   
83.
胶东金矿成矿流体同位素的地质特征   总被引:13,自引:0,他引:13  
胶东大、中型金矿床成矿流体的H、O同位素组成显示出金矿床的初生成矿流体以岩浆水为主,在重熔花岗岩形成作用中继承了部分变质水,在高温阶段的成矿作用中以岩浆水为主,其后逐渐向大气降水方向演化,只有少部分矿床属大气降水成因。本文探讨了H.P.泰勒的水岩反应同位素交换质量平衡方程的应用条件,当水/岩比很小时,该方程不能确切判定关于成矿流体的成因,本文提供了以地质条件为前提的解析方法。成矿流体的Rb-Sr年龄揭示出胶东金矿主要成矿期为燕山晚期,成矿流体的ISr与玲珑花岗质杂岩体中的郭家店、郭家岭型岩体一致,而成矿作用特别是与郭家岭型岩体重熔形成作用有关。  相似文献   
84.
Based on the theoretical modelling of water-rock δD-δ18O isotopic exchange process, the evolution and sources of ore-forming fluid in four metallogenic epochs of the Jinduicheng superlarge-scale porphyry-type molybdenum deposit were investigated. It was revealed that in the pre-metallogenic and early-metallogenic epochs, the ore-forming fluid was a residual fluid derived from magmatic water-wall rock interaction at middle to high temperatures (T = 250–500°C) and lower W/R ratios (0.1> = W/R>0.001), while in the metallogenic and postmetallogenic epochs, the ore-forming fluid was a residual fluid derived from meteoric water-wall rock interaction at middle to lower temperatures (T = 150–310°C) and relatively high W/R ratios (0.5>W/R≥0.1). The meteoric water played an important role in molybdenum mineralization, and at the main metallogenic epoch the W/R ratio reached its maximum value. This project was financially supported by both the National Natural Science Foundation of China and the Key Research Project of the Ministry of Geology and Mineral Resources of China.  相似文献   
85.
成矿流体的浓缩作用及浓缩方式研究   总被引:12,自引:3,他引:9  
林文蔚  殷秀兰 《地球学报》1998,19(2):158-165
几乎所有的大中型热液矿床中都广泛存在着热液蚀变现象,且伴随强烈的成矿流体的浓缩作用。初始浓度较稀薄的含矿流体,通过水岩反应生成富水矿物的交代带使热液中的自由水固化在蚀变岩石中,热液中的自由水与C、S等组分反应而被大量地消耗,流体的减压沸腾都可极大地促进成矿热液中自由水的减少,从而使残余流体中金属浓度增高。可以通过构造-蚀变岩填图、实验模拟、特征指示性元素性状研究和交代剖面的数学模拟获得成矿溶液浓缩的幅度,进而判定矿化规模,通常在大、中型矿床中都发生过多次流体浓缩作用,依据水岩反应中流体浓缩理论,建立了含矿  相似文献   
86.
夹皮沟金矿北西向剪切带存在着长英质和镁铁质两类糜棱岩系列岩石,韧性变形中伴随的大量流体与糜棱岩之间发生了强烈的水岩反应:斜长石绢云母化和钠化,暗色矿物绿泥石化,以及大范围强烈的碳酸盐化。  相似文献   
87.
Two kinds of mylonite series rocks,felsic and mafic,have been recognized in the NW-striking shear zone of the Jiapigou gold belt.During ductile deformation, a large amount of fluid interacted intensively with the mylonite series rocks:plagioclases were sericitized and the An values declined rapidly,finally all of them were transformed to albites;dark minerals were gradually replaced by chlorites(mostly ripidolite).Meanwhile,large-scale and extensive carbonation also took place,and the carbonatization minerals varied from calcite to dolomite and ankerite with the development of deformation.Theδ^13 Cvalues of the carbonates are-3.0‰--5.6‰suggesting a deep source of carbon.The ductile deformation is nearly an iso-volume one(fv=1).With the enhancement of shear deformation,SiO2 in the two mylonite series rocks was depleted,while volatile components such as CO2 and H2O,and some ore-forming elements such as Au and S were obviously enriched.But it is noted that the enrichment of Au in both the mylonite series rocks did not reach the paygrade of gold.The released SiO2 from water-rock interactions occurred in the form of colloids and absorbed gold in the fluid.When brittle structures were formed locally in the ductile in the ductile shear zone,the ore-forming fluids migrated to the structures along microfractures,and precipitated auriferous quartz because of reduction of pressure and temperature.Fluid inclusion study shows that the temperature and pressure of the ore-forming fluids are 245-292℃and 95.4-131.7MPa respectively;the salinity is 12.88-16.33wt% NaCl;the fluid-phase is rich in Ca^2 ,K^ ,Na^ ,Mg^2 ,F^- and Cl^-,while the gaseous phases are rich in CO2 and CH4.The δD and δ^18O values of the ore-forming fluid are -84.48‰--91.73‰and -0.247‰- 2.715‰respectively,suggesting that the fluid is composed predominantly of meteoric water.  相似文献   
88.
以大豆“中黄-14”为试验材料, 利用OTC-1型农田开顶式气室, 首次模拟研究单独CO2和O3浓度倍增及其交互作用对大豆生物量、产量及其构成因子、同化产物分配形式和收获指数的影响。与未通CO2和O3的处理相比, 单独CO2浓度倍增对生物量、产量、荚果串数、荚数、籽粒数、籽粒重具有正效应, O3为明显的负效应, 通气时段越长效果越明显; 持续的CO2浓度和O3浓度倍增交互作用表现为CO2的影响大于O3; CO2和O3交互作用逐渐达到浓度倍增的处理, 由于O3剂量逐渐累积和阶段性增加, 对大豆刺激逐渐增强, 最终O3的负效应与CO2的正效应相近。单独O3浓度倍增抑制光合产物向根和籽粒的输送, 向叶茎的输送明显增强, 使根冠比 (RSR)、子粒与茎杆比 (GCR) 明显下降, 长期作用可使大豆收获指数 (HI) 减小, 叶重比 (LWR) 显著增加, 且随通气时间的延长影响增大; CO2浓度倍增及其交互作用对RSR、LWR、GCR和HI影响相对较小, 仅在±10%左右。  相似文献   
89.
Vibratory excitation generates not only reflections and refractions of wave fields on the subsurface interfaces but also electromagnetic waves with different frequencies. In this paper we address the vibration-induced effects on the spontaneous potential field. The effects of controllable vibration on the spontaneous potential field were studied under real field geologic conditions. Experimental data confirmed that the vibration-induced effects on the spontaneous potential field do exist under field conditions. Monitoring records over a long time interval showed that there existed three information zones in the vibration-induced effects on spontaneous potential field:These are the signal-variant zone, the extreme-stable zone and the relaxation-recovery zone. Combined with different well-site data, it was concluded that the time-variant features of the anomalies in the information zones was closely related to the properties of the subsurface liquid (oil and water).  相似文献   
90.
水-岩相互作用模拟的研究进展   总被引:9,自引:0,他引:9  
水 岩相互作用的地球化学模拟已在模型建立和软件的开发方面取得了较大的进展。地球化学模型发展经历了从反向模拟到正向模拟,以及到现在的反应性溶质运移模拟的发展过程。许多计算模拟软件被开发出并投入到实际应用中,现在的模拟技术已能处理较大范围内温度变化、压力变化、组分变化,以及各种地质条件下的水 岩地球化学作用。许多水 岩相互作用问题要回答地质作用的过去历史,要解释或预测未来可能水环境变化,通过模拟已获得满意的解决。目前水 岩作用地球化学模拟取得的重要进步是动力学模型和耦合运移模拟已取得了实质性进展,并应用于实际研究之中。  相似文献   
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