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991.
992.
Seventy-six samples of formation waters were collected from oil wells producing from the Aux Vases or Cypress Formations in the Illinois Basin. Forty core samples of the reservoir rocks were also collected from the two formations. Analyses of the samples indicated that the total dissolved solids content (TDS) of the waters ranged from 43,300 to 151,400 mg/L, far exceeding the 35,400 mg/L of TDS found in typical seawater. Cl-Br relations suggested that high salinities in the Aux Vases and Cypress formation waters resulted from the evaporation of original seawater and subsequent mixing of the evaporated seawater with concentrated halite solutions. Mixing with the halite solutions increased Na and Cl concentrations and diluted the concentration of other ions in the formation waters. The elemental concentrations were influenced further by diagenetic reactions with silicate and carbonate minerals. Diagenetic signatures revealed by fluid chemistry and rock mineralogy delineated the water-rock interactions that took place in the Aux Vases and Cypress sandstones. Dissolution of K-feldspar released K into the solution, leading to the formation of authigenic illite and mixed-layered illite/smectite. Some Mg was removed from the solution by the formation of authigenic chlorite and dolomite. Dolomitization, calcite recrystallization, and contribution from clay minerals raised Sr levels significantly in the formation waters. The trend of increasing TDS of the saline formation waters with depth can be explained with density stratification. But, it is difficult to explain the combination of the increasing TDS and increasing Ca/Na ratio with depth without invoking the controversial 'ion filtration' mechanism. 相似文献
993.
秦山核电站邻近水域浮游动物的群落结构和年际变化 总被引:2,自引:0,他引:2
描述了1995~1996年度秦山核电站邻近水域浮游动物的生物量、丰度、群落结构及其与环境因子的关系,并与1989~1990年度的资料进行了对比分析。结果表明,秦山核电Ⅰ期工程运行以来,对该水域浮游动物群落结构未产生明显的影响 相似文献
994.
东沙群岛西南海域单站潮流及温盐特征分析 总被引:1,自引:0,他引:1
利用东沙群岛西南海域定点站(20°41’N,115°49’E)3个航次观测的海流、水温资料及同期的温、盐度断面资料,用谱分析方法对该站海流、水温时间序列进行分析。结果表明,该站海流和水温的时间变化都具有明显的全日周期和半日周期波动的特征,潮流为不规则全日潮,主轴顺时针方向旋转。内潮为全日内潮占优,且具有间歇特征。和总流动类似,斜压运动也主要是顺时针方向旋转的。 相似文献
995.
伶仃河口湾铜鼓水域水沙净输运分析 总被引:7,自引:1,他引:6
根据对珠江伶仃河口湾铜鼓水域丰水期9个测站大、中、小潮三次同步水文泥沙资料及57个底质样品的分析结果,本文讨论了此水域的水沙净输运趋势。结果表明,铜鼓水域表层余流向海,浅滩测站中底层余流指向河口方向,欧拉余流主要由径流构成。沟槽悬沙输运以净平流作用为主,浅滩区则以向上游的潮抽吸输运为主。沉积物净输运趋势显示铜鼓浅滩是海陆双向底质输运的汇聚地带 相似文献
996.
北京地区地热测井与热储层研究 总被引:3,自引:0,他引:3
北京地热测井由电阻率,自电,天然放射性,井温,井径形成地热测井系列,在划分地层,了解井温,水量等方面取得重要参数资料,为北京地热的勘探,开发,评价提供必要的依据。 相似文献
997.
Giorgio Capasso Rocco Favara Salvatore Francofonte Salvatore Inguaggiato 《Journal of Volcanology and Geothermal Research》1999,88(3):209
Gas samples from some fumaroles at ‘La Fossa' crater and Baia di Levante on Vulcano Island and from a diffuse soil gas emission were analysed during 1995–1996, along with water samples from thermal wells in the area of Vulcano Porto. During 1996, we observed a significant increase both in the gas/steam ratio and in the CO2 concentration, as well as strong variations in δ13CCO2, δDH2O and δ18OH2O of fumarolic gases. These variations are probably related to an increased inflow of deep fluids of magmatic origin. The temperatures of fumaroles did not show remarkable variations except for fumarole F11. In this case, temperature increased by about 80°C from February to August 1996. During the same period, remarkable variations in temperature, phreatic level and chemical and isotopic composition of water were also recorded in one of the geothermal wells in the Vulcano Porto area (Camping Sicilia; T60°C). The observed variations in this well are probably related to a pressure build-up, occurring at least in the surficial part of the system, because of increased gas flux and/or decreased permeability of the fumarolic degassing system. Chemical and isotopic composition of the water showed that during this evolutionary phase, the content of fumarolic condensate in this well was about 80 to 90%. Based on the observation of physical and chemical variables of the Camping Sicilia fluids, during this phase of activity, it is concluded that this area is affected by a phreatic eruption hazard if a volcanic episode with high energy discharge in a limited time span occurs. It follows that this well may be considered as a preferential point for volcanic activity monitoring, both in the case of normal routine surveillance and in the case of inaccessibility to the crater area. 相似文献
998.
999.
浙江宁波协和石油化工厂附近水域浮游植物的研究 总被引:3,自引:0,他引:3
对1993年8月(夏季)和12月(冬季)在协和石化厂区附近水域获得的浮游植物样品作了鉴定和分析。结果表明,调查区共有浮游植物4门29属60种,可划分为三个生态类群:广布性类群、暖水性类群和温带性类群。浮游植物细胞丰度达66×103~2107×103个/m3。具有明显的季节变化。冬季平均细胞丰度(746.6×103±630.8×103个/m3)大于夏季(201.8×103±146.8×103个/m3)。主要优势种为中肋骨条藻,琼氏圆筛藻和有棘圆筛藻。浮游植物丰度的昼夜变化有随着日照增强而增高的趋势,最高细胞丰度(10221×103个/m3)出现在12时。影响浮游植物丰度分布的主要环境因子是径流、水温和日照等。 相似文献
1000.
台湾东北和西北部沿岸海域的浮游多毛类 总被引:2,自引:0,他引:2
本文报道东北季风初期台湾东北和西北部沿岸海域的浮游多毛类,计11种。文中对2种新纪录种类作了描述。 相似文献