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921.
Evolution model and formation mechanism of bio-thermocatalytic transitional zone gas 总被引:1,自引:0,他引:1
As a new genetic type of natural gas exploration area, the bio-thermocatalytic transitional zone gas (BTTZG) has been highly
stressed by geologists both at home and abroad. Systematic study on the generation mechanism of hydrocarbon at the transitional
zone is presented. Based on simulating experiments and geochemistry analysis of the source rock with lower evolution, a hydrocarbon-forming
model at the transitional zone has been established. The mechanism is proposed that under the condition of low temperature
and pressure combining with extremely active structural stress and clay mineral catalysis, BTTZG is formed by de-group of
soluble organic matter and polarized compositions through orthocarbon ion as well as by condensation polymerization of aromatic
ring-rich insoluble organic matter. This mechanism controls the formation of BTTZG, and furthermore, BTTZG is the product
of superimposition and interaction of all the factors mentioned above. 相似文献
922.
In this contribution we discuss the geometry-free GPS single baseline model and show how the least-squares ambiguities are affected by changes in the stochastic model. We particularly pay attention to the effect of time correlation, cross-correlation and satellite elevation dependence. We also differentiate between the impact on the location of the ambiguity search space and the impact on the size and shape of the search space. The analysis is carried out for both the model in which the ionospheric delays are assumed absent, and for the model in which they are assumed present. The former model is applicable to short baselines only. 相似文献
923.
Gennady A. Kivman 《Surveys in Geophysics》1997,18(6):621-643
The problem of deriving tidal fields from observations by reason of incompleteness and imperfectness of every data set practically available has an infinitely large number of allowable solutions fitting the data within measurement errors and hence can be treated as ill-posed. Therefore, interpolating the data always relies on some a priori assumptions concerning the tides, which provide a rule of sampling or, in other words, a regularization of the ill-posed problem. Data assimilation procedures used in large scale tide modeling are viewed in a common mathematical framework as such regularizations. It is shown that they all (basis functions expansion, parameter estimation, nudging, objective analysis, general inversion, and extended general inversion), including those (objective analysis and general inversion) originally formulated in stochastic terms, may be considered as utilizations of one of the three general methods suggested by the theory of ill-posed problems. The problem of grid refinement critical for inverse methods and nudging is discussed. 相似文献
924.
925.
926.
在计算覆盖整个黄晔裂谷200口人工井(包括少部分探井)沉降量的基础上,总结本区二种基本沉降曲线模式。统计出热沉降(St)与初始沉降(Si)之比为0.6,依此为约束条件与大陆岩石圈伸展的地球动力学正演模式进行对比,与简单剪切模式预测的热沉降与初始沉降之比值及几何效应更接近。进一步证实黄骅裂谷以简单剪切机制形成的地球动力学模式更合理,这与著名的以纯剪模式形成的北海伸展盆地不同 相似文献
927.
酸性污染物欧拉型输送转化模式的研究 总被引:2,自引:0,他引:2
数值模式是研究酸性污染及其长距离输送特性的一种重要方法。70年代以来,国内外发展了许多欧拉型的输送转化模式,我国在欧拉型酸性污染物长距离输送模式的研究中也取得了重要进展。主要介绍了国内外的欧拉酸性污染物输送转化模式,并就模式的发展方向进行了讨论。 相似文献
928.
星载合成孔径雷达遥感及多卫星遥感数据融合方法 总被引:5,自引:0,他引:5
合成孔径雷达(SAR)数据,以其特有的成像机理和对地物信息的属性描述及其全天时、全天候作业能力,形成了对传统多光谱遥感数据的互补。通过数据融合技术,可以优化遥感信息资源,实现多卫星遥感数据的优势互补,使遥感信息得到最大限度的利用,从而为地学研究中的各种模型方法和决策系统提供科学依据。根据信息的抽象程度不同,融合可分为原始数据融合、目标级融合和决策级融合三个层次。在不同的层次具有相对应的信息融合方法。 相似文献
929.
根据矿床的地球物理地球化学异常特征,磁异常与金矿体的关系,地球化学异常及其垂向分带规律,归纳出矿床地球物理地球化学找矿模式和找矿标志。 相似文献
930.
Yang Wunian Zhu Zhangsen Institute of Remote Sensing GIS Chengdu University of Technology Chengdu Sichuan Liu Xinzhu Yang Wencai 《《地质学报》英文版》1997,71(3):344-354
The structural feature shown on a remote sensing image is a synthetic result ofcombination of the deformations produced during the entire geological history of an area.Therefore, the respective tectonic stress field of each of the different stages in the complexdeformation of an area can be reconstructed in three steps: (1) geological structures formed atdifferent times are distinguished in remote sensing image interpretation; (2) structuraldeformation fields at different stages are determined by analyzing relationships betweenmicrostructures (joints and fractures) and the related structures (folds and faults); and (3)tectonic stress fields at different stages are respectively recovered through a study of the featuresof structural deformation fields in different periods. Circular structures and related circlular and radial joints are correlated in space to con-cealed structural rises. The authors propose a new method for establishing a natural model ofthe concealed structural rises and calculating the tectonic stress field by using quantitative dataof the remote sensing information of circular structures and related linear structures. 相似文献