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901.
裂谷盆地生油层中火山岩及其矿物与有机质的相互作用——油气生成的催化和加氢作用研究进展及展望 总被引:40,自引:0,他引:40
我国裂谷盆地生油层中常有火山岩发育。在研究它们共生模式的基础上,利用地球化学和模拟实验等手段探索埋藏成岩期火山矿物与有机质的相互作用。初步成果表明,一些火山矿物对有机质生烃具有催化和加氢作用,可以使生油岩在较低温度和压力条件下生成较多的油气。但是不同火山矿物对油气生成的催化加氢效果及其动力学特征、这种成因类型的油气识别方法、成藏模式等,还需深入研究。因此,本研究对于丰富油气成因理论、提供新的找油领域具有重要意义。 相似文献
902.
本文通过对东南沿海地震背景和地震破坏性经济损失,结合国内外城市化进程中防震减灾经济性对比研究,认为地震破坏的负面效应所带来的经济损失十分巨大。因而必须加强防震减灾工作为保障城市化顺利发展服务。 相似文献
903.
Tianshan is one of the longest and most active intracontinental orogenic belts in the world. Due to the collision between Indian and Eurasian plates since Cenozoic, the Tianshan has been suffering from intense compression, shortening and uplifting. With the continuous extension of deformation to the foreland direction, a series of active reverse fault fold belts have been formed. The Xihu anticline is the fourth row of active fold reverse fault zone on the leading edge of the north Tianshan foreland basin. For the north Tianshan Mountains, predecessors have carried out a lot of research on the activity of the second and third rows of the active fold-reverse faults, and achieved fruitful results. But there is no systematic study on the Quaternary activities of the Xihu anticline zone. How is the structural belt distributed in space?What are the geometric and kinematic characteristics?What are the fold types and growth mechanism?How does the deformation amount and characteristics of anticline change?In view of these problems, we chose Xihu anticline as the research object. Through the analysis of surface geology, topography and geomorphology and the interpretation of seismic reflection profile across the anticline, we studied the geometry, kinematic characteristics, fold type and growth mechanism of the structural belt, and calculated the shortening, uplift and interlayer strain of the anticline by area depth strain analysis.
In this paper, by interpreting the five seismic reflection profiles across the anticline belt, and combining the characteristics of surface geology and geomorphology, we studied the types, growth mechanism, geometry and kinematics characteristics, and deformation amount of the fold. The deformation length of Xihu anticline is more than 47km from west to east, in which the hidden length is more than 14km. The maximum deformation width of the exposed area is 8.5km. The Xihu anticline is characterized by small surface deformation, simple structural style and symmetrical occurrence. The interpretation of seismic reflection profile shows that the deep structural style of the anticline is relatively complex. In addition to the continuous development of a series of secondary faults in the interior of Xihu anticline, an anticline with small deformation amplitude(Xihubei anticline)is continuously developed in the north of Xihu anticline. The terrain high point of Xihu anticline is located about 12km west of Kuitun River. The deformation amplitude decreases rapidly to the east and decreases slowly to the west, which is consistent with the interpretation results of seismic reflection profile and the calculation results of shortening. The Xihu anticline is a detachment fold with the growth type of limb rotation. The deformation of Xihu anticline is calculated by area depth strain analysis method. The shortening of five seismic reflection sections A, B, C, D and E is(650±70) m, (1 070±70) m, (780±50) m, (200±40) m and(130±30) m, respectively. The shortening amount is the largest near the seismic reflection profile B of the anticline, and decreases gradually along the strike to the east and west ends of the anticline, with a more rapidly decrease to the east, which indicates that the topographic high point is also a structural high point. The excess area caused by the inflow of external material or outflow of internal matter is between -0.34km2 to 0.56km2. The average shortening of the Xihubei anticline is between(60±10) m and(130±40) m, and the excess area caused by the inflow of external material is between 0.50km2 and 0.74km2. The initial locations of the growth strata at the east part is about 1.9~2.0km underground, and the initial location of the growth strata at the west part is about 3.7km underground. We can see the strata overlying the Xihu anticline at 3.3km under ground, the strata above are basically not deformed, indicating that this section of the anticline is no longer active. 相似文献
In this paper, by interpreting the five seismic reflection profiles across the anticline belt, and combining the characteristics of surface geology and geomorphology, we studied the types, growth mechanism, geometry and kinematics characteristics, and deformation amount of the fold. The deformation length of Xihu anticline is more than 47km from west to east, in which the hidden length is more than 14km. The maximum deformation width of the exposed area is 8.5km. The Xihu anticline is characterized by small surface deformation, simple structural style and symmetrical occurrence. The interpretation of seismic reflection profile shows that the deep structural style of the anticline is relatively complex. In addition to the continuous development of a series of secondary faults in the interior of Xihu anticline, an anticline with small deformation amplitude(Xihubei anticline)is continuously developed in the north of Xihu anticline. The terrain high point of Xihu anticline is located about 12km west of Kuitun River. The deformation amplitude decreases rapidly to the east and decreases slowly to the west, which is consistent with the interpretation results of seismic reflection profile and the calculation results of shortening. The Xihu anticline is a detachment fold with the growth type of limb rotation. The deformation of Xihu anticline is calculated by area depth strain analysis method. The shortening of five seismic reflection sections A, B, C, D and E is(650±70) m, (1 070±70) m, (780±50) m, (200±40) m and(130±30) m, respectively. The shortening amount is the largest near the seismic reflection profile B of the anticline, and decreases gradually along the strike to the east and west ends of the anticline, with a more rapidly decrease to the east, which indicates that the topographic high point is also a structural high point. The excess area caused by the inflow of external material or outflow of internal matter is between -0.34km2 to 0.56km2. The average shortening of the Xihubei anticline is between(60±10) m and(130±40) m, and the excess area caused by the inflow of external material is between 0.50km2 and 0.74km2. The initial locations of the growth strata at the east part is about 1.9~2.0km underground, and the initial location of the growth strata at the west part is about 3.7km underground. We can see the strata overlying the Xihu anticline at 3.3km under ground, the strata above are basically not deformed, indicating that this section of the anticline is no longer active. 相似文献
904.
A nonlinear critical layer and a Kelvin cat's eye excited thereupon are simulated through four schemes in the context of a nonlinear quasi-geostrophic barotropic vorticity equation model with forced stationary wave acting along the southern boundary to investigate effects of tropical steady forcing on the genesis,maintenance and oscillation of a subtropical high(STH).Evidence suggests that the southern forcing is responsible for the planetary quasi-steady anticyclonic Kelvin cat's eye-form flow field inside the nonlinear critical layer,with the eye shifting,vigor and shape changing quite similar to the behaviors of a summer STH,in striking contrast to the northern stationary forcing.As such,the southern boundary-caused cat's eye is likely to be an even more important mechanism for STH genesis and evolution.In addition,a physical mechanism is introduced for quasi-steady planetary wave moving through the critical layer at subtropical latitudes. 相似文献
905.
There were 102 meso-α-scale convective systems(MαCSs)generated over China and theneighboring sea during June—August 1995.Those MαCSs were concentrated in three major areas:the west of South China,Sichuan Basin,and the middle and lower reaches of the Changjiang andthe Huanghe River Basin.Six cases of MαCS in different regions are given to show the variety ofthe MαCS genesis and development by the distributions of their cold-cloud-shield black bodytemperature. 相似文献
906.
应用地震波速CT和吸收CT相结合的方法对山东省招远市界河金矿隐伏采空区进行了联合探测研究.波速CT是利用地震波走时资料反演地质体内部波速结构;吸收CT是通过能量变化观测反演吸收系数分布.地震波速对岩性敏感,吸收系数与岩石的完整性关系更密切在界河金矿采空区探测中利用地震波速和吸收系数为层析物理量,在巷道和地表间进行透射观测,以优于2m的分辨率清楚地揭示了测区内采空区和断裂破碎带的分布,探测结果已被后期的采掘所证实.探测的成功为解决同类问题提供了一种可行的方案,对促进工程地球物理探测技术的发展也有重要意义. 相似文献
907.
908.
The Yiluo River is the largest tributary for the middle and lower reaches of the Yellow River below Sanmenxia Dam. Changes of the hydrological processes in the Yiluo River basin, influenced by the climatic variability and human activities, can directly affect ecological integrity in the lower reach of the Yellow River. Understanding the impact of the climatic variability and human activities on the hydrological processes in the Yiluo River basin is especially important to maintain the ecosystem integrity and sustain the society development in the lower reach of the Yellow River basin. In this study, the temporal trends of annual precipitation, air temperature, reference evapotranspiration (ET0) and runoff during 1961–2000 in the Yiluo River basin were explored by the Mann‐Kendall method (M‐K method), Yamamoto method and linear fitted model. The impacts of the climatic variability and vegetation changes on the annual runoff were discussed by the empirical model and simple water balance model and their contribution to change of annual runoff have been estimated. Results indicated that (i) significant upwards trend for air temperature and significant downwards trend both for precipitation and ET0 were detected by the M‐K method at 95% confidence level. And the consistent trends were obtained by the linear fitted model; (ii) the abrupt change started from 1987 detected by the M‐K method and Yamamoto method, and so the annual runoff during 1961–2000 was divided into two periods: baseline period (1961–1986) and changeable period (1987–2000); and (iii) the vegetation changes were the main cause for change of annual runoff from baseline period to changeable period, and climatic variability contributed a little to the change of annual runoff of the Yiluo River. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
909.
Guimei WAN Liangjie TANG Wenzheng JIN . Basin Reservoir Research Centre China University of Petroleum Beijing China. Key Laboratory for Hydrocarbon Accumulation Mechanism of Ministry of Education China University of Petroleum Ministry of Education Beijing China 《东北亚地学研究》2007,10(2):156-165
Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective. 相似文献
910.
目的:通过数据挖掘分析针刺治疗支气管哮喘的选穴规律。方法:检索中国知网(CNKI)、维普中文科技期刊数据库(VIP)、万方数据(WANFANG DATA)、中国生物医学文献服务系统(SinoMed)自建库至2022年9月20日收录的针刺治疗支气管哮喘的临床研究文献,通过中医传承辅助平台系统V2.5进行频次、关联规则、聚类、核心处方分析。结果:共纳入42篇文献,包含52个腧穴,总使用频次为272次,使用频次排前10位的腧穴依次为:肺俞、定喘、足三里、丰隆、膻中、尺泽、列缺、天突、风门、大椎;常用腧穴主要分布于足太阳膀胱经、手太阴肺经、任脉。特定穴多选用背俞穴、交会穴及五输穴。腧穴配伍以肺俞-定喘最为常见。核心腧穴处方:肺俞、定喘、足三里、丰隆、膻中、风门。结论:特定穴的选用是针刺治疗哮喘组方的重要组成部分,临床应重视“治脏者,治其俞”之选穴思想,突出“局部配穴”“远近配穴”“前后配穴”之配穴特点,从而体现“扶正祛邪,标本兼顾”之治疗原则。 相似文献