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在调研了国内外气烟囱研究成果与思路的基础上,通过全新的地震解决方案——OpendTect平台提供的基于属性多层感知器(MLP)的人工神经网络(ANN)的方法预测气烟囱的发生概率体,并利用倾角导向体对算法进行改进,提出倾角控制下的地震气烟囱识别技术,很好地补充并发展了模式识别技术在地震勘探领域的应用。通常该技术一方面可以解释运移通道和浅层气成藏的原因;另一方面,形成的气烟囱地震数据体还可以预测源岩的发育情况;此外,对于判别断层封闭性也非常适用。最后应用这一技术对海拉尔盆地贝尔凹陷一含油区块的运移通道和成藏规律进行研究,分析该研究区的断裂发育特征和运移通道类型,总结了油源、通道、储层和盖层的空间配置关系,并建立相应的成藏模式。 相似文献
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C. Werner S. Hurwitz W.C. Evans J.B. Lowenstern D. Bergfeld H. Heasler C. Jaworowski A. Hunt 《Journal of Volcanology and Geothermal Research》2008
We characterize and quantify volatile emissions at Hot Spring Basin (HSB), a large acid-sulfate region that lies just outside the northeastern edge of the 640 ka Yellowstone Caldera. Relative to other thermal areas in Yellowstone, HSB gases are rich in He and H2, and mildly enriched in CH4 and H2S. Gas compositions are consistent with boiling directly off a deep geothermal liquid at depth as it migrates toward the surface. This fluid, and the gases evolved from it, carries geochemical signatures of magmatic volatiles and water–rock reactions with multiple crustal sources, including limestones or quartz-rich sediments with low K/U (or 40?Ar/4?He). Variations in gas chemistry across the region reflect reservoir heterogeneity and variable degrees of boiling. Gas-geothermometer temperatures approach 300 °C and suggest that the reservoir feeding HSB is one of the hottest at Yellowstone. Diffuse CO2 flux in the western basin of HSB, as measured by accumulation-chamber methods, is similar in magnitude to other acid-sulfate areas of Yellowstone and is well correlated to shallow soil temperatures. The extrapolation of diffuse CO2 fluxes across all the thermal/altered area suggests that 410 ± 140 t d− 1 CO2 are emitted at HSB (vent emissions not included). Diffuse fluxes of H2S were measured in Yellowstone for the first time and likely exceed 2.4 t d− 1 at HSB. Comparing estimates of the total estimated diffuse H2S emission to the amount of sulfur as SO42− in streams indicates ~ 50% of the original H2S in the gas emission is lost into shallow groundwater, precipitated as native sulfur, or vented through fumaroles. We estimate the heat output of HSB as ~ 140–370 MW using CO2 as a tracer for steam condensate, but not including the contribution from fumaroles and hydrothermal vents. Overall, the diffuse heat and volatile fluxes of HSB are as great as some active volcanoes, but they are a small fraction (1–3% for CO2, 2–8% for heat) of that estimated for the entire Yellowstone system. 相似文献
176.
The gold contents of 59 samples of mantle-derived xenoliths, along with 85 samples of sulfide assem-blages in them, of Cenozoic basalt from eight districts in eastern China are analyzed. The gold contents of mantle xenoliths usually fall in the range of 10-9―10-8, whereas those of the sulfide assemblages fall in the range of 10-4―10-2. This implies that the latter are several hundred thousand times higher than the former, and thus that Au in the mantle is concentrated mostly in sulfide assemblages. Gold con-tents of both mantle-derived xenoliths and sulfide assemblages in them are inhomogeneous spatially, but their distribution rules are similar. Except the samples from Hainan Province, either the mantle xenoliths with high gold content or sulfide assemblages of the mantle-derived xenoliths with high gold content are distributed mostly on the north and south margins of the North China platform (Hannuoba of Hebei Province and Linqu, Changle of Shandong Province), corresponding to districts with concen-trated gold deposits in northwest Hebei Province and Jiaodong Peninsula of Shandong Province. This may reflect the correlativity in age, nature and composition between the continental crust and the un-derlying lithospheric mantle. The underlying lithospheric mantle of the North China platform is an an-cient gold-rich lithospheric mantle. The gold-rich lithospheric mantle may be the material source of later activation, enrichment, transportation and mineralization of gold by auriferous CO2 mantle fluids. 相似文献
177.
Analyses of trace elements of the Lower Palaeozoic carbonate rock strata in Beijing show that the contents of As, Hg, F increase from primary carbonate rocks to weathered carbonate rocks and from primary carbonate rocks to the soil coexisting with carbonate rocks, but the distribution regularity of S is not obvious. In the whole weathered stages, the sorption of As is mainly affected by Fe2O3. In soil Fe2O3 is also the main affecting factor of Hg enrichment. The main existing forms of Hg in primary carbonate rocks should simply be physical adsorption, coprecipitation and false isomorphous form between surface of carbonate rock and Hg. In soil the enrichment of F has little relationship with sul-fides and Fe2O3. In primary carbonate rocks, F is mainly absorbed by sulfides and clay minerals, etc. Weathered samples have closer genetic relationships with primary carbonate rocks. This also implies that weathered carbonate rocks have the close existing forms to that of primary carbonate rocks. In primary carbonate rocks FeS2 and FeS are the main forms of S, and sulfides have fixation effect on some heavy metals, whereas in weathered carbonate rocks and soil the fixation effect is weakened. 相似文献
178.
铜镍硫化物矿床的成冈——以诺里尔斯克(俄罗斯)和金川(中国)为例 总被引:15,自引:0,他引:15
与超基性岩浆作用有关的铜镍硫化物矿床主要有两种成矿建造,一种为含铬建造,另一种为含铂建造。尖晶石类矿物成分的变化清楚地反映了这两类建造的成矿属性,含铬建造的尖晶石属于铬铁矿-尖晶石系列,含铂建造中则为尖晶石-磁铁矿系列。从含铬建造向含铂建造转变的原因,可以解释为超基性岩艇中硫的作用增加,从而引起反应:4FeO+S=FeS+Fe3O4(磁铁矿),同时分散性铂族元素的专属性特征也发生相应变化(Ru+Os+Ir)→(Pt+Pd)。因此,含铬建造中主要富含Ru、Os和Ir,而含铂建造中则富含Pt和Pd。超基性岩浆作用中硫的化学活动性增加与基碱度增加直接有关。因此,含铂的超基性岩大多数情况下与富碱的玄武岩形成共生组合,当富铁熔浆发生硫化作用时,将会导致硫化物与硅酸岩熔浆的不混融,从而形成矿浆,据此,金川含铂铜镍矿石不是矿 相似文献
179.
WANG Ruiting MAO Jingwen HE Ying WANG Dongsheng TANG Zhongli 《大地构造与成矿学(英文版)》2005,29(2):152-163
The platinum-group element geochemistry of rocks and ores from Jinchuan super-large copper-nickel sulfide deposit is systemically studied in this paper. The Cu/Pd mean ratio of Jinchuan intrusion is lower than that of original mantle magma, which indicates that these ultrabasic rocks were crystallized from magma that lost Pd in the form of melting segregation of sulfides. The PGE of the rocks show trend of partial melting, similar to that of mantle peridotite, which shows that magma formation occurs during rock-forming and ore-forming processes. The chondrite normalized PGE patterns of the rocks and ores are well related to each other, which signifies the signatures of multi-episode magmatic intrusion, melting and differentiation in the formation processes of rocks and ores. In addition, analyses about the relation between PGE and S, and study on Re-Os isotopes indicate that few contamination of the crustal substances occurred during the magmatic intrusion and the formation of deposit. However, contamination by crustal substances helps to supply part of the S for the enrichment of PGE. Meanwhile, the hydrothermal process is also advantageous for the enrichment of PGE, especially lbr Pt and Pd, due to deep melting segregation. The characteristic parameters (such as Pt/(Pt+Pd), (Pt+Pd)/(Ru+Ir+Os), Pd/Ir, Cu/(Ni+Cu), and so on.) for platinum-group elements for Jinchuan sulfide copper-nickel deposit show the same features as those for sulfide copper-nickel deposit related to basic magma, which also illustrates its original magma property representative of Mg-high tholeiite. Therefore, it is the marie (not ultramafic) magma that resulted in the formation of the superlarge sulfide copper-nickel deposit enriched in Cu and PGE. To sum up, the geochemical characteristics of platinum-group elements in rocks and ores from Jinchuan copper-nickel sulfide deposit are constrained by the continental rift tectonic environment, the parent magma features, the enriched mantel magma source, the complex metallogenesis and PGE geochemical signatures, and this would be rather significant for the study about the genetic mechanism of copper-nickel sulfide deposits. 相似文献
180.
峨口铁矿中硫化物的特征与成因研究 总被引:1,自引:0,他引:1
硫是铁矿中的有害元素。峨口铁矿中硫主要以磁黄铁矿和黄铁矿两种形式存在。本区硫化物有三个形成期次。第五期为变质作用形成的星点状硫化物;第二期为变质后热液阶段形成的脉状硫化物;第三期为后期热液阶段形成的裂隙充填式硫化物。 相似文献