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991.
The distribution of Oil & gas fields shows their close relationship with the most active tectonic regions. This is not a coincidence but having a scientific reasons. The crustal active regions, refer to the places where the active natural earthquake, volcanic activities, underground water happened, and the areas of the leaking off of natural gas to the surface of the crust. The magma of volcanic activities brings the organic "kitchen range body" hydrocarbon- generating model and inorganic genetic hydrocarbon to the regions covered by volcanic rock. Underground water brings a catalytic hydrocarbongenerating model for organic matter, and the leaking- off of H2 and CO2 contributes a synthetic hydrocarbon - generating model. Volcanic activities bring the assemblage of Source, Reservoir and Seal formed by the sediments and magma the sedimentary basins, and the hydrocarbon - generating system with a "water - volcano" binary structure is formed. All these conditions are favorable and excellent for the formation of oil & gas fields. The distribution of American oil & gas fields have very close relationship with the mines of Fe, Mn, Ct, Mo, W and V, deposits of Zn, Cu, V, Pb, Al and Hg, and the deposits of fluorite, sulfur, potassium salt, phosphate and halite, and the distribution of sulfate- chloride of river water. The reason why few oil & gas fields discovered in the regions covered by volcanic rock in western America maybe because of the view of "inconsistency between petroleum and volcano". Further more, It's very difficult to carry out a geophysical exploration in such kinds of regions.This paper examined a few hydrocarbon-generating models (systems) mentioned above and came up with some fresh ideas on the exploration in the areas covered with volcanic rocks. 相似文献
992.
对秦岭造山带区域成矿背景、矿床的时空分布、典型矿床矿田赋存部位、区域成矿元素地球化学背景、多重岩片控矿理论,构造成矿体系、成矿物质来源、矿床成因类型、矿床区域成矿模式进行了讨论,在对大量资料研究的基础上提出了新认识。最后指出秦巴地区进一步寻找大型矿床的地区。 相似文献
993.
This paper proposes a numerical model for jointed rock masses within the 3‐D numerical manifold method (NMM) framework equipped with a customized contact algorithm. The strength of rock sample containing a few sets of discontinuities is first investigated. The results of models with simple geometries are compared with the available analytical solutions to verify the developed computer code, whereas models with complex geometries are simulated to better understand the fundamental behavior and failure mechanism of jointed rock mass. Furthermore, the stability of jointed rock mass in an underground excavation is studied, where rock failure process is determined by the 3‐D NMM simulation. The simulation results provide valuable guidance on excavation process design and stabilization design in rock engineering practice. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
994.
滩间山地壳自中元古代蓟县纪以来经历了长期复杂的演化历史。金矿床的形成与本区地壳构造演化密切相关。蓟县纪早期,万洞沟群黑色岩系沉积于NE 向同生断裂控制的凹陷中,矿源层产生;蓟县纪晚期,区域变质作用为成矿奠定了基础;加里东期,韧性剪切带对金矿富集有重要作用;华力西期,脉岩型矿石生成;印支期,伴随推覆作用有微弱矿化的叠加;喜山期,氧化矿石形成。因此,滩间山金矿床是本区地壳构造演化的产物,属黑色岩系同构造多因复成金矿床,即滩间山型金矿床。 相似文献
995.
北秦岭存在A、B、C三类火山岩系列,对应着幔源型、壳幔混染型和壳幔混合型成因类型。火山岩系列和成因类型的系统变化,反映了多旋回壳幔物质迁移特证。 相似文献
996.
Two-phase flow in fractured rock is an important phenomenon for a range of practical problems, not the least of which is
non-aqueous phase liquid (NAPL) contamination of groundwater. Although multiphase systems have long been studied in the petroleum
field, in the hydrogeological field progress has only just reaches the point where models are being developed. Scale effect
is one of the main issues of concern. Although models presented in this paper have the potential to provide useful predictions,
they can only be used to investigate a variety of possible scenarios with parameters being specified in the form of distribution
of values. The calibration and validation of all but the simplest of these models poses a formidable task, with great demands
on hydrogeologists and geophysicists to provide adequate data.
Received: 20 May 1996 · Accepted: 19 August 1996 相似文献
997.
Equilibrium erosion of soft rock shores with a shallow or absent beach under increased sea level rise 总被引:1,自引:0,他引:1
A process-based numerical model was used to explore the response of soft rock shores with low volume beaches to variable rates of sea level rise. Equilibrium recession rates were simulated for ranges of wave height and period, tidal amplitude, rock strength, beach volume and rate of sea level rise. Equilibrium shore profiles were found to be steeper with higher rates of sea level rise. Beaches were represented as protective surfaces yet were found to cause no significant reduction in equilibrium recession rate when their volumes were below a critical threshold. Reduced equilibrium recession rates were found with beaches that extended sufficiently far below low tide level. The model results imply that, given several constraints, a very simple relationship exists between increased rates of sea level rise and the response of eroding composite soft rock/low volume beach shores. 相似文献
998.
在总结分析现有复杂断层及倒转褶皱3维建模方法的基础上,提出一种基于广义三棱柱(GTP)的3维交互建模方法(岩柱体分区RPBP建模法)。文中定义了岩柱体、界限三角形两个重要概念,RPBP法可以通过构建断层界限三角形,将复杂断层系转化为多个简单断层系,然后采用构建简单断层系模型的方法来实现复杂断层系的3维建模;而对于倒转褶皱,RPBP法则通过构建褶皱轴界限三角形避免数据局部重复和冲突,使GTP建模过程得以顺利进行。实验表明,该方法能便捷可靠地实现含多断层相互切割、倒转褶皱等复杂地质体的真3维建模。 相似文献
999.
姜修道 《地球科学与环境学报》1995,(2)
驾鹿金矿床是小秦岭金矿带中一个比较特殊的矿床类型,产于古老韧性剪切带中,围岩蚀变强烈而广泛,尤其是成脉前的钾长石化。蚀变带及其中的石英脉控制了金矿体的产出,矿床属蚀变岩型金矿,成矿时代为燕山晚期.本文在论述矿床地质特征的基础上,通过稳定同位素研究,认为燕山期构造热事件是成矿的主导控制因素,成矿溶液来自大气降水,成矿物质则部分来自太华群,部分来自上覆中元古界高山河组,矿床成因属大气降水热液矿床. 相似文献
1000.