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43.
埕岛油田海上石油平台基础冲刷研究 总被引:6,自引:1,他引:6
海洋石油平台的建立会改变平台周围的水动力条件,其中平台的基础及与之连接的海底管缆(输油管道、注水管道、海底电缆等)附近产生冲刷现象,对平台和海底管缆的安全造成威胁。根据对研究区典型平台的4次实洲水深并结合以往资料,分析了埕岛油田海上石油平台基础冲刷的过程及其规律。 相似文献
44.
南海北缘东部盆地油气资源研究 总被引:5,自引:0,他引:5
南海北缘东部的珠江口盆地及台西南盆地蕴藏着十分丰富的油气资源,根据区域构造背景、盆地发育分布的特点及中、新生代的油气地质条件,结合含油气构造、油气田、油气井的分布规律,利用油气资源评价的理论、方法,对区内的油气资源进行了综合研究,并按照油气资源状况划分出油气富集区、油气潜力区、油气远景区,在此基础上,再进一步划分出4条油气富集带、11条油气潜力带、8条油气远景带,充分显示了该区石油、天然气的分布规律和油气地质特点,为商业性的勘探开发和理论研究奠定了基础。 相似文献
45.
REEdistributioninwater-sedimentinterfacesystematdeepoceanfloor¥ZhangLijie;LiuJihuaandYaoDe(ReceivedFebruary1,1994;acceptedMay... 相似文献
46.
东太平洋沉积物U的地球化学 总被引:4,自引:0,他引:4
本文对地矿部“海洋四号”科学考察船1987-1989年在东赤道太平洋CC区所取得的27个深海表层沉积样品进行U的地球化学分析,探讨了U在深海沉积中的地球化学行为,结果表明,不同类型沉积的U含量不同,平均值由大至小的次序的含沸石粘土(2.16×10^-6),硅质粘土(1.95×10^-6),硅质软泥(1.65×10^-6),钙质硅质粘土(1.59×10^-6),在同类型沉积中U的分散性较大;U在区域 相似文献
47.
A. A. De Almeida 《Earth, Moon, and Planets》1992,56(1):61-74
Emission fluxes of CN, C2 and C3 carbon-bearing molecular species observed in the coma of comets Bennett (1969i 1970II), West (1975n 1976VI), P Halley (1982i), Hartley-Good (19851) and Bradfield (1987s) are analysed in the framework of Haser model. CN, C2 and C3 production rates are determined using recently derived fluorescence efficiencies. The dependence of CN, C2 and C3 production rates on the heliocentric distance and the possible correlations among these radicals is studied and briefly discussed. 相似文献
48.
Apatite fission-track (AFT) thermochronological modeling as a diagnostic tool for periods of stability (peneplanation) and tectonic activity (orogeny) has been broadly used in tectonic studies of Central Asia in recent years. We discuss more than 100 AFT ages of samples from the Kyrgyz Tien Shan and Altai and compare them with AFT data from northern Kazakhstan. Geological, geomorphological, and AFT data indicate intense activity in the Late Cenozoic Eurasian continental interior. The impact from the India-Eurasia collision on the northern Tien Shan, Altai, and northern Kazakhstan regions showed up at 11, 5, and 3 Ma, respectively, as a result of stress propagation into the continent, with the ensuing reactivation and mountain growth. We hypothesize that a distant effect of the Late Cenozoic India-Eurasia collision was to rejuvenate Paleozoic fault zones and to deform the Mesozoic sedimentary cover north of the collision front as far as the West Siberian Plate. The reactivation facilitated formation of tectonic oil and gas traps. The activity in northern Central Asia under the effect of the Indian indentation into Eurasia appears to continue and may evolve to include uplift of southern West Siberian plate with uplift. 相似文献
49.
Elisa Sacchi Gian Maria Zuppi Luca Pizzino Fedora Quattrocchi Salvatore Lombardi 《Aquatic Geochemistry》2008,14(4):301-319
The EC funded Geochemical Seismic Zonation program (EEC GSZ Project 1996–1998) chose Sardinia as a low-seismicity site, in which the relationships between fluid geochemistry and seismo-tectonics
had to be investigated and results compared with outcomes from other selected high-seismicity sites. A first article, examining
the role of fault segmentation and seismic quiescence on the geochemical composition of groundwaters and gases, has already
been presented (Angelone et al. 2005). This article deals with environmental isotopes which, together with selected hydrochemical data, give hints on tectonically-related
fluid circulations. Four water-dominated hydrothermal systems were considered, all located along regional fault systems and
discharging groundwaters belonging to the Na–HCO3 and Na–Cl facies. In the considered systems, groundwater circulation takes place, principally, in the Palaeozoic Crystalline
Basement (PCB), with the exception of the Logudoro system, where hydrological circuits develop in the Mesozoic Carbonate Platform
(MCP). The high CO2 contents, the non-attainment of fluid-rock equilibrium and the large lithological variability prevent the construction of
a unique hydrogeological–geochemical conceptual model. In this case, stable isotopes provide a useful tool to describe the
origin of fluids and their subterranean movements. Stable isotopes of water, integrated with hydrochemical data, indicate
that fluids are derived from three main end members. The dominant component is a relatively recent local meteoric water; the
second one is marine water; and the third one is a fossil freshwater, depleted in heavy isotopes with respect to modern rains.
The latter end member entered the aquifer system in the past, when climatic conditions were greatly different from today.
At least two circulation systems can be recognised, namely a shallow cold system and a deep hydrothermal system, as well as
two distinct hydrological processes: (1) gravity-controlled descent of cold water towards greater depths and (2) convection
linked to a thermal gradient, causing deep fluids to rise up from the hydrothermal reservoir towards the surface. The highly
variable δ13CTDIC values suggest the presence of two distinct CO2 sources, namely, a biogenic one and a thermogenic one. The relation between the isotopic compositions of CO2 and He indicates an increased mantle signature in uprising CO2-rich fluids. 相似文献
50.
B. R. De 《Astrophysics and Space Science》1996,239(1):25-33
Maxwell's displacement current equation is interpreted in the light of recent work to show that static magnetic field in free space should have a colocated and contemporaneous mass that is neither embodied in, nor can be anticipated from, the mass-energy relation. Thus magnetostatic field in the universe represents an invisible mass. Some consequences are discussed. 相似文献