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31.
将现代人工神经网络方法应用于地质学的判别分析,通过实例计算表明,无论是对于两组判别分析还是多组判别分析,人工神经网络方法都是切实可行的。 相似文献
32.
电感耦合等离子体质谱(ICP—MS)具有灵敏度高、检出限低、选择性好、线性范围宽、能进行多元素和同位素比测定等优点,广泛应用于环境、地质、医药、食品和高纯物质等领域。ICP—MS与其他进样及分析技术的联用,大大地扩展了其应用范围。重点介绍了ICP—MS与激光烧蚀(LA)、高效液相色谱(HPLC)及气相色谱(GC)的联用技术,探讨了它们在海洋地质研究中的应用前景。 相似文献
33.
等深流沉积研究现状与展望 总被引:6,自引:0,他引:6
本文根据国内外等深流及其沉积的研究成果,概述了它们的研究进展,且详细阐述了等深流沉积特征和沉积类型,并指出等深岩丘的发现是该领域最为重要、最具特色的突出成果以及等深流沉积研究的油气勘探意义.虽然随着深海钻探计划和大洋钻探项目的开展,等深流沉积研究取得了较大进展,但现代等深流沉积和古代等深流沉积的研究在一定程度上发展尚不平衡,仍存在着较多问题,尤其是在古代等深流沉积研究方面显得更为薄弱.最为重要的是,等深流沉积的识别是该领域研究的最大难题.因此,在其未来研究上,应注意运用地震波识别、遥感等现代科技调查手段,进行多学科综合研究,尽快建立一套完善的识别标志,如沉积学标志、古生物标志等,以促使其逐渐成为海洋沉积学中一个更为完善的研究领域. 相似文献
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青岛胶州湾3.2级地震构造背景与控震断裂 总被引:1,自引:0,他引:1
本文应用构造分析的方法 ,对青岛胶州湾 3.2级地震发生的地震地质背景和构造背景进行分析。结果表明 :胶州湾 3.2级地震主要受 NEE向郝官庄断裂和 NNW向大沽河断裂控制 ,并根据现代活动断裂的标志 ,对上述 2组断裂活动性特征作了阐述 相似文献
38.
Detailed structural interpretation of the recently acquired deep seismic multichannel profiles along the Iberian Atlantic Margins (IAM Project) provides new results on the geodynamic evolution of the eastern part of the Azores-Gibraltar plate boundary. Thrusting and folding of the oceanic basement and of Mesozoic and Cenozoic sedimentary cover of the Gorringe Bank region are consistent with the N–S convergence of Iberia and Africa. Compressive structures in the Gorringe Bank region are spread over a wide area. Deformation under compression took place mainly in Tertiary times, as is evidenced by a basal unconformity and several discontinuities in Tertiary sediments, although some deformation has also been recorded in Quaternary sediments. The compressive structures in the Gulf of Cadiz are E–W oriented thrusts, folds and related diapiric structures. N–S oriented transpressive deformation is likely to occur in the western Portuguese platform. There is no continuity of structures from the oceanic to the continental domain, suggesting that deformation transfers from one side to the other through a transcurrent fault zone. The fault contact between the two domains is located in the ocean-continent transition zone. 相似文献
39.
通过电镜、电子探针和X射线等项分析,对东海沉积物中的有孔虫、腹足类、双壳类、苔藓、珊瑚、海胆等骨屑进行了矿物学研究,确定了矿物成分与生物属种的关系,并基于有孔虫壳体化学成分将壳体分为均质壳和异质壳,生物碳酸盐中镁主要富集在方解石及镁方解石中,锶在方解石和镁方解石中的分配系数(D)相似,为0.11—0.14;在文石质骨屑中D=1.09-1.20。碳氧同位素组成与生物属种有明显关系。据一些有孔虫壳体氧同位素偏差值计算的水温来看,本次测定的有孔虫属种的骨屑不能作为理想的骨屑温度计。 相似文献
40.
Theoretical aspects of cap-rock and fault seals for single- and two-phase hydrocarbon columns 总被引:6,自引:0,他引:6
Cap-rock seals can be divided genetically into those that fail by capillary leakage (membrane seals) and those whose capillary entry pressures are so high that seal failure preferentially occurs by fracturing and/or wedging open of faults (hydraulic seals). A given membrane seal can trap a larger oil column than gas column at shallow depths, but below a critical depth (interval), gas is more easily sealed than oil. This critical depth increases with lower API gravity, lower oil GOR and overpressured conditions (for the gas phase). These observations arise from a series of modelling studies of membrane sealing and can be conveniently represented using pressure/ depth (P/D) profiles through sealed hydrocarbon columns. P/D diagrams have been applied to the more complex situation of the membrane sealing of a gas cap underlain by an oil rim; at seal capacity, such a two-phase column will be always greater than if only oil or gas occurs below the seal.These conclusions contrast with those for hydraulic seals where the seal capacity to oil always exceeds that for gas. Moreover, a trapped two-phase column, at hydraulic seal capacity will be less than the maximum-allowed oil-only column, but more than the maximum gas-only column. Unlike membrane seals, hydraulic seal capacity should be directly related to cap-rock thickness, in addition to the magnitude of the minimum effective stress in the sealing layer and the degree of overpressure development in the sequence as a whole.Fault-related seals are effectively analogous to membrane cap-rocks which have been tilted to the angle of the fault plane. Consequently, all of the above conclusions derived for membrane cap-rocks apply to both sealing faults sensu stricto (fault plane itself seals) and juxtaposition faults (hydrocarbon trapped laterally against a juxtaposed sealing unit). The maximum-allowed two-phase column trapped by a sealing fault is greater than for equivalent oil-only and gas-only columns, but less than that predicted for a horizontal membrane cap-rock under similar conditions. Where a two-phase column is present on both sides of a sealing fault (which is at two-phase seal capacity), a deeper oil/water contact (OWC) in one fault block is associated with a deeper gas/oil contact (GOC) compared with the adjacent fault block. If the fault seal is discontinuous in the gas leg, however, the deeper OWC is accompanied by a shallower GOC, whereas a break in the fault seal in the oil leg results in a common OWC in both fault blocks, even though separate GOC's exist. Schematic P/D profiles are provided for each of the above situations from which a series of fundamental equations governing single- and two-phase cap-rock and fault seal capacities can be derived. These relationships may have significant implications for exploration prospect appraisal exercises where more meaningful estimates of differential seal capacities can be made.The membrane sealing theory developed herein assumes that all reservoirs and seals are water-wet and no hydrodynamic flow exists. The conclusions on membrane seal capacity place constraints on the migration efficiency of gas along low-permeabiligy paths at depth where fracturing, wedging open of faults and/or diffusion process may be more important. Contrary to previous assertions, it is speculated that leakage of hydrocarbons through membrane seals occurs in distinct pulses such that the seal is at or near the theoretically calculated seal capacity, once this has been initially attained.Finally, the developed seal theory and P/D profile concepts are applied to a series of development geological problems including the effects of differential depletion, and degree of aquifer support, on sealing fault leakage, and the evaluation of barriers to vertical cross-flow using RFT profiles through depleted reservoirs. It is shown that imbibition processes and dynamic effects related to active cross-flow across such barriers often preclude quantitative analysis and solution of these problems for which simulation studies are usually required. 相似文献