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1.
中国古生教授学会微体古生物学分会举行代表大会和学术年会中国古竽物学会微体古物学分会第五次会员代表大分暨第六次不术年会于1996年1月24日到30日在福州市召开。来自全国地质、石油、煤炭的和产、科研和大学的100多位代表参加了这次大会和学术研讨。大会共... 相似文献
2.
Yehuda Ben-Zion 《Geophysical Journal International》1990,101(3):507-528
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E. Tóth F. Deak C. S. Gyurkócza Z. S. Kasztovszky R. Kuczi G. Marx B. Nagy S. Oberstedt L. Sajó-Bohus C. S. Sükösd G. Toth N. Vajda 《Environmental Geology》1997,31(1-2):123-127
A steady radon exhalation is assumed in most publications. In a village of North-East Hungary, however, high radon concentrations
have been measured, differing strongly in neighbouring houses and varying in time, due to the interplay of geochemical phenomena.
Received: 20 November 1995 · Accepted: 18 June 1996 相似文献
5.
柴达木盆地北缘侏罗系不同沉积环境烃源岩生物标志物特征及其应用 总被引:2,自引:0,他引:2
柴达木盆地北缘地区侏罗系(中下侏罗统)的优质烃源岩主要发育于湖相与三角洲相环境。研究了不同时代、不同沉积环境中烃源岩的生物标志物组成特征,结果发现,有3类化合物的分布与组成差异显著,包括三环萜烷(C19、C20、C21)的分布型式、重排藿烷的丰度以及规则甾烷的相对组成。其中,不同时代的差异主要体现在规则甾烷组成上;而不同沉积环境的差异主要体现为三环萜烷(C19、C20、C21)的分布型式及重排藿烷的丰度。分析认为,这些差异与烃源岩的沉积环境及其生源组成有密切关系。据此,初步将这些参数应用于两方面研究,一是为划分地层沉积环境提供“生物标志物相标志”,二是研究油源对比,取得良好效果。因此,本文研究结果具有重要实用价值与参考意义。 相似文献
6.
Thomas B. Boving Mark H. Stolt Janelle Augenstern Brian Brosnan 《Environmental Geology》2008,55(3):571-582
The control of polluted surface runoff and the assessment of possible impacts on groundwater is a concern at the local and
regional scale. On this background, a study investigates possible impacts of organic and inorganic pollutants (including bacteria)
originating from a permeable asphalt parking lot on the water quality immediately beneath it. The functioning of the permeable
pavement, including clogging and restricted vertical percolation, was also evaluated. Four nested sample ports (shallow and
deep) were installed below low- and high-traffic areas, including one port outside the parking lot. At least initially there
was a good hydraulic connection between the parking surface and the shallow sample ports. The presence of a geotextile layer
at the base of the parking lot structure, however, was identified in lab tests as one factor restricting vertical percolation
to the deeper ports. Clogging of the permeable surface was most pronounced in heavy traffic areas and below snow pile storage
areas. Corroborated by high electric conductivity and chloride measurements, sand brought in by cars during winter was the
principal cause for clogging. No bacteria or BOD were found in percolating water. Polycyclic aromatic hydrocarbons (PAH) were
present at concentrations near minimum detection limit. Nutrients (nitrate and phosphate) were being leached into the ground
via the permeable parking lot surface at annual flux rates of 0.45–0.84 g/m2/year. A multi-species tracer test demonstrated a retention capacity of the permeable parking lot structure of >90% for metals
and 27% for nutrients, respectively. 相似文献
7.
This paper presents an example of application of the double solid reactant method (DSRM) of Accornero and Marini (Environmental
Geology, 2007a), an effective way for modeling the fate of several dissolved trace elements during water–rock interaction. The EQ3/6 software
package was used for simulating the irreversible water–rock mass transfer accompanying the generation of the groundwaters
of the Porto Plain shallow aquifer, starting from a degassed diluted crateric steam condensate. Reaction path modeling was
performed in reaction progress mode and under closed-system conditions. The simulations assumed: (1) bulk dissolution (i.e.,
without any constraint on the kinetics of dissolution/precipitation reactions) of a single solid phase, a leucite-latitic
glass, and (2) precipitation of amorphous silica, barite, alunite, jarosite, anhydrite, kaolinite, a solid mixture of smectites,
fluorite, a solid mixture of hydroxides, illite-K, a solid mixture of saponites, a solid mixture of trigonal carbonates and
a solid mixture of orthorhombic carbonates. Analytical concentrations of major chemical elements and several trace elements
(Cr, Mn, Fe, Ni, Cu, Zn, As, Sr and Ba) in groundwaters were satisfactorily reproduced. In addition to these simulations,
similar runs for a rhyolite, a latite and a trachyte permitted to calculate major oxide contents for the authigenic paragenesis
which are comparable, to a first approximation, with the corresponding data measured for local altered rocks belonging to
the silicic, advanced argillic and intermediate argillic alteration facies. The important role played by both the solid mixture
of trigonal carbonates as sequestrator of Mn, Zn, Cu and Ni and the solid mixture of orthorhombic carbonates as scavenger
of Sr and Ba is emphasized.
相似文献
Luigi Marini (Corresponding author)Email: |
8.
Samples of O isotopic tracer were mlleMed at Sections P3,P25,PcM-t/2-E and PCM-1/2.w in both the Fast China Sea and the area to the east of the Ryūkyū-gunto during October-November,1991.Analytical results of the δ18O are as follows: (1) In the Kuroshio area,the δ18O isolines are almost parallel to the 200 m isobath.The value of δ18O is negative and reaches minimum mt the main axis of the Kuroshio,and increases on both sides.(2) In the Taiwan Warm Current (TWC) area there is a high δ18O tongue extending to the northeast.(3) In the area near the coast,the distribution of δ18O isoline shows that the Changjiang River runoff diffuses seaward and the land-ocean isotopic effect from the nearshore to the offshore.(4) The values of δ18O are from -1.0×10-3 to -0.5×10-3 in the shelf.(5) There is a low mre of δ18O value(<-1.6×10-3) at the 600 m layer in the Kuroshio area,which is quite in accord with the existence of a low salinity mre (S G 34.30) between the 600 and 800 m layers in the same area.Finally,the mrrelations of the δ18O with the salinity and temperature,the upwelling and so on are discussed. 相似文献
9.
南黄海陆架沉积学研究 总被引:4,自引:0,他引:4
黄海中部、济州岛西南,存在厚层的泥质沉积,它们分别与上述地区的冷涡活动区相对应。在两个泥质沉积区之间又出现连接它们的通道,形成别有特征的“冷涡-通道”沉积体系。经分析发现,这个沉积体系,完全受控于黄海暖流、冷涡及其相关的环流体系。此外,在黄海西南部及东海北部海底发现大面积砂岩及其砾石,揭示了黄、东海陆架沉积物的新源地。 相似文献
10.
东营城区高精度三维地震采集方法研究 总被引:3,自引:0,他引:3
根据东营城区内建筑物较多,环境干扰较大,地下构造复杂,断裂非常发育,目的层埋藏深,资料信噪比较低的特点,以地震老资料和钻井资料为基础,建立地震地质模型,利用射线追踪技术选取合适的观测系统参数。充分利用卫星数字地图,没计了灵活多变的观测系统,采用可控震源与炸药震源配合使用方法,及时对城区内地下面元的覆盖次数、方位角和炮检距的分布进行质量监控,利用现场处理系统对资料进行及时分析,提高了地震资料品质。所获得的东营城区高精度三维地震采集资料显示,其浅中层分辨率和中深层信噪比都有了明显改善,取得了良好的地质效果。 相似文献