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51.
有机质热演化与极低级变质作用 总被引:8,自引:0,他引:8
岩石中有机质热演化特征可以灵敏于反映岩石的成岩作用到变质作用之间(即极低级变质作用)的温度、压力变化情况。笔者对有机质热变指标在极低级变质作用界线、变质带划分和变质作用温度、压力和时间演化等方面的应用进行了综述和探讨。 相似文献
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东秦岭北缘煤的变质作用与板块构造的关系 总被引:2,自引:1,他引:2
以河南省东秦岭造山带北缘山西组二1煤层的煤岩、煤质、煤有机地球化学和“晶核”结构的综合研究为前提,结合板块构造和地球物理场的研究分析,认为该区二1煤的变质热源主要与长期复杂的板块俯冲、A型碰撞所引起的地壳结构调整而使前陆盆地区岩石圈结构变化,大地热流急增的结果有关。二1煤的变质主要经历了早期(印支期前)的区域深成变质(达肥-气煤)和后期(印支-燕山期)的典型异常热变质作用(达无烟煤-高阶无烟煤)。 相似文献
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Water is the most active component in all geological systems.It has an important effect on the physical properties of minerals and melts.It also plays a key role in the evolution of the Earth.Accurate thermodynamics data on water are currently confined to pressures below 1.0GPa and temperatures below 900℃.Presented in this paper are new data available on the P-T properties of water at pressures up to 5.0GPa,develoged from differential thermal analysis and ultrasonic wave amplitude analysis.It has been found that there may exist another ternary point at 3.0GPa and that ultrasonic wave amplitude change of ice-water transition shows two inflection points above 2.0GPa, consistent with the two peaks of differential thermal curves above 2.0GPa .It may be a new phenomenon which needs further study. 相似文献
56.
In this paper,a comprehensive analysis and review of the advances in the research of human body comfort degree is made.Based on the studies of human thermal equilibrium theories contributed by previous researchers,different apparent temperature models corresponding to different environments are set up in accordance with the current situation and the characteristics of metabolism in different groups of people in China.After case studies and comparison with present dominant human body comfort degree statistical models,it is proved that the apparent temperature models have high rationality and wide adaptability.Furthermore,the comfort scaling standard according to apparent temperature is suggested,which is suitable for the middle latitude regions in China. 相似文献
57.
This paper designs three quasi-geostrophic barotropic models with a radial/horizontal grid length being 2 kin,one in the polar coordinates,one on a stationary typhoon circulation condition and another on a non-stationary typhoon circulation condition in the Cartesian coordinates,to investigate the effects of azimuthal and radial linear advections,and nonlinear advection on the inward propagation of mesoscale vorticity and the changes of typhoon intensity.Results show that the azimuthal linear advection may result in the formation of spiral vorticity bands;the radial linear advection in a certain parameter set is able to transfer vorticity inwards,leading to a slight enhancement of typhoon;the nonlinear advection of perturbation vorticity on a stationary typhoon circulation condition may transfer more vorticities inwards,thus resulting in a distinct enhancement of typhoon;and the nonlinear advection on a non-stationary typhoon circulation condition possesses duality,i.e.on the one hand,the advection increases the vorticity of inward propagation,thus favorable to the intensification of typhoon,and on the other hand,in the inward propagation process of vorticity the originally concentric and axisymmetric structure of typhoon basic flow is damaged,and a complex flow pattern forms,which in turn tends to weaken the circulation of typhoon.At last the paper discusses the possible applications of those results in typhoon intensity prediction. 相似文献
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1IntroductionThecarbonisotopiccompositionofnaturalgasesisregardedasacontanttracerusedinthegeochemicalresearchofnaturalgases .Basedonthecarbonisotopiccomposition ,thegenetictypesofnaturalgasesarebasicallydividedtodeterminethematurationofnaturalgasesandmakegas sourcecorrelations (Stahl,1 973;StahlandCarey ,1 975;Stahletal.,1 977;James ,1 983;Schoell,1 983,1 988;DaiJinxingetal.,1 992 ;FuJiamoetal.,1 992 ;XuYongchang ,1 994 ) .Theformationofnaturalgasescouldbededucedintermsofcarbonisotopicvar… 相似文献
59.
Zhuravlev Igor Igorevich 《冰川冻土》2004,26(Z1):128-132
Complex experimental research of thermal properties of oil-contaminated frozen soils was carried out. On the basis of the obtained results the influence of the various factors connected with oil pollution on heat transfer in frozen soils was analyzed. And the model of heat transfer in frozen soils was offered. 相似文献
60.
多年冻土地区建筑物地基的热稳定性技术 总被引:1,自引:0,他引:1
Thermal stabilization of soils (including freezing of thawed soils and cooling of permafrost) is known to be the effective method providing stable support for buildings and structures in cold regions.Seasonal thermo-stabilizers (STS) are mainly used in construction. The predicted climate warming because of natural and man-caused factors determines wide application of STS in permafrost regions. A STS transfers heat from its underground part (evaporator) to the aerial part (condenser) owing to natural temperature difference between them during a cold season. We have been working out and manufacturing different types of two-phase, vapor-liquid STS. Aluminum alloys are used in our STS to prevent corrosion and to increase their efficiency. They are successfully used in the northern regions of Western Siberia, in particular, at the railway Obskaya Bovanenkovo. The paper presents some technical parameters of new STS, the results of their experimental study and computer simulation, as well as experience features. 相似文献