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Based on the examination of the global researches on oil and gas provinces and large gas fields and the analysis of the features, attributes and distribution of large gas provinces and gas fields, this paper puts forward three indicators of determining large oil and gas provinces: spatial indicator, reservoir-forming indicator and resource indicator. It classifies the gas accumulated areas and large gas provinces in China and analyzes the controlling factors on the distribution of large gas provinces and large gas fields: the lateral distribution is mainly controlled by high-energy sedimentary facies and constructive diagenetic facies, palaeo-highs and their periclinal zones, deep faults, etc, and the vertical distribution is mainly controlled by unconformities, series of evaporates and deep low-velocity highly-conductive beds, etc. It also reveals the main geological characteristics of large gas provinces and large gas fields in China. Large gas fields in four-type basins have their own characteristics and onland large gas fields are dominantly developed in foreland basins and craton basins; there are three types of gas sources, of which, coal is the main source with high gas generating intensity and varying origins; reservoir rocks of the large gas fields (provinces) are of various types and dominated generally by low-middle permeability and porosity pore-type reservoirs; structural traps and litho-stratigraphic traps coexist in Chinese large gas fields and form dense high abundance and large-area low and middle-abundance large gas fields; most of the large gas fields have late hydrocarbon-generation peaks and reservoir formation, and experienced the process of multiple-stage charging and late finalization; large gas provinces (fields) have good sealing and preservation conditions, and evaporates seals are largely developed in large and extra-large gas fields. This paper intends to shed light on the exploration and development of large gas fields (provinces) through analyzing their geological characteristics. 相似文献
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我国地震科技进步的回顾与展望(一) 总被引:9,自引:2,他引:9
本文对近半个世纪以来我国地震科技发展所经历的艰辛历程和所取得的长足进步作了简要回顾。阐明了如下3点:(1)全社会对减轻地震灾害及减轻地震对社会经济生活影响的强烈要求是推动我国地震科技发展的强劲动力;(2)为人民生命财产安全、经济可持续发展和社会稳定提供更好的保障是推动我国地震科技发展的根本目的;(3)坚持地震监测等技术系统建设与地震科学研究的辩证统一,并处理好任务性、科学性、可行性之间的关系是推动我国地震科技进步性质遵循的重要原则。地震预报预防工作所取得的某些成功和所遭受的许多挫折不断加深了人们对地震的发生条件和孕育发生过程复杂性的认识,促进了地震监测等技术系统的改造与现代化建设和地震科学研究的深入。尤其是20世纪最后5年,地震监测等技术系统的改造和现代化建设使地震预报预防研究与实践的技术支撑得到较明显的改善,既突出重点,又广泛探索的地震科学研究,使人们对我国大陆地震的发生条件和孕育发生过程,以及震害特征与机理研究等取得一些新的重要认识。所取得的长足进步不仅使防震减灾工作实效得以明显提高,而且为加速新世纪,首先是“十五”期间我国地震科技的进步进一步奠定了基础。在回顾历史的基础上,阐明了当前和今后一段时期我国地震科技发展的总体要求和应重点加强的10个方面的工作,即地震观测台网的数字化改造与建设;地震前兆观测台网的改造与建设;强地震动观测台网的建设;地震实验室的建设;地震信息和应急指挥与紧急救援技术系统的建设;地震短临预报的研究;地震中长期预报的研究;地震动衰减和震害机理与震害控制的研究;城市地震活动断层探测与震害预测的研究;地震科学和地球科学有关领域的基础研究。期望通过这些努力使我国地震科技全面达到国际先进水平,地震预报预防的理论、技术、方法显著改进,防震减灾工作实效显著提高。 相似文献
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地震科技期刊改革与发展的构想 总被引:5,自引:2,他引:5
科技期刊是反映一个国家科技学术创新水平的窗口,是科技信息的使者。其作为忠实记录、连续积累和储备科技信息的重要载体及时传播、交流着70%以上的科技信息,地震科技期刊亦是如此。从地震科技期刊如何走向世界的视角,对地震科技期刊的现状、加入世贸组织后面临的挑战、生存、发展的对策,以及如何加快国际化进程等方面提出了看法、建议和构想,指出,只有将地震科技期刊做大、做美、做强,才能增强国际竞争力,才能形成自己的拳头产品,才能向国际地震品牌期刊行列讲军。 相似文献
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梳理近年来山西省防震减灾社会宣教工作的发展历程,分析其现状,进一步探索防震减灾社会宣教工作在建立完善联动机制,广泛发动社会力量参与,加强防震减灾文化建设并充分利用宣传阵地开展深度宣传,加强产品研发及宣传效果跟踪调研工作等方面的发展新思路。 相似文献
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Imaging the PP- and PS-wave for the elastic vector wave reverse-time migration requires separating the P- and S-waves during the wave field extrapolation. The amplitude and phase of the P- and S-waves are distorted when divergence and curl operators are used to separate the P- and S-waves. We present a P- and S-wave amplitude-preserving separation algorithm for the elastic wavefield extrapolation. First, we add the P-wave pressure and P-wave vibration velocity equation to the conventional elastic wave equation to decompose the P- and S-wave vectors. Then, we synthesize the scalar P- and S-wave from the vector Pand S-wave to obtain the scalar P- and S-wave. The amplitude-preserved separated P- and S-waves are imaged based on the vector wave reverse-time migration (RTM). This method ensures that the amplitude and phase of the separated P- and S-wave remain unchanged compared with the divergence and curl operators. In addition, after decomposition, the P-wave pressure and vibration velocity can be used to suppress the interlayer reflection noise and to correct the S-wave polarity. This improves the image quality of P- and S-wave in multicomponent seismic data and the true-amplitude elastic reverse time migration used in prestack inversion. 相似文献
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In this paper, the long time series data of the well water-level data of 12 wells in the Sichuan and Yunnan area is analyzed by the Baytap-G tidal analysis software, and well water level tidal response characteristic parameters (amplitude ratio and phase change) are extracted. We analyzed the features of the shape and stage change, and characteristic parameters of the tidal response of well water level before and after the earthquakes, which can provide a new method and approach to analyzing the response relationships between well water level and earth tide and barometric pressure. The results show that Luguhu Well and 9 other wells are affected by earth tides, and their well water level amplitude ratios and phases are relatively stable; the Nanxi Well and Dayao Well water level changes are affected by the barometric pressure combined with tide force, and their well water level amplitude ratios and phases are more discrete. The water level amplitude ratios and phases of Jiangyou Well, Luguhu Well and Dongchuan Well are significant to large earthquakes, and the relationship between seismic energy density and water level amplitude ratios and phases of M2 wave of the three wells are presented. 相似文献
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流域土地利用/覆被变化的水文效应及洪水响应 总被引:17,自引:1,他引:17
干旱与洪涝灾害已成为全球关心的重大问题.土地利用/覆被变化影响雨水的截留、下渗、蒸发等水文要素及其产汇流过程,并进而影响流域出口断面的流量过程,加大流域洪涝灾害发生的频率和强度.深入研究土地利用/覆被变化对洪涝灾害的影响,对于社会经济可持续发展具重要意义.通过分析和总结已进行的有关流域土地利用/覆被变化的水文效应及洪水响应研究工作进展,讨论了其研究内容、方法及现有工作的不足之处. 相似文献
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《中国科学D辑(英文版)》2008,(Z1)
Based on the examination of the global researches on oil and gas provinces and large gas fields and the analysis of the features,attributes and distribution of large gas provinces and gas fields,this paper puts forward three indicators of determining large oil and gas provinces:spatial indicator,reservoir-forming indicator and resource indicator.It classifies the gas accumulated areas and large gas provinces in China and analyzes the controlling factors on the distribution of large gas provinces and large gas fields:the lateral distribution is mainly controlled by high-energy sedimentary facies and constructive diagenetic facies,palaeo-highs and their periclinal zones,deep faults,etc,and the vertical distribution is mainly controlled by unconformities,series of evaporates and deep low-velocity highly-conductive beds,etc.It also reveals the main geological characteristics of large gas provinces and large gas fields in China.Large gas fields in four-type basins have their own characteristics and onland large gas fields are dominantly developed in foreland basins and craton basins;there are three types of gas sources,of which,coal is the main source with high gas generating intensity and varying origins;reservoir rocks of the large gas fields(provinces)are of various types and dominated generally by low-middle permeability and porosity pore-type reservoirs;structural traps and litho-stratigraphic traps coexist in Chinese large gas fields and form dense high abundance and large-area low and middle-abundance large gas fields;most of the large gas fields have late hydrocarbon-generation peaks and reservoir formation,and experienced the process of multiple-stage charging and late finalization; large gas provinces(fields)have good sealing and preservation conditions,and evaporates seals are largely developed in large and extra-large gas fields.This paper intends to shed light on the exploration and development of large gas fields(provinces)through analyzing their geological characteristics. 相似文献
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Eric Tabacchi Johannes Steiger Dov Corenblit Michael T. Monaghan Anne-Marie Planty-Tabacchi 《Aquatic Sciences - Research Across Boundaries》2009,71(3):279-289
The structure and function of alluvial Highly Dynamic River Systems (HDRS) are driven by highly variable hydrological disturbance
regimes, and alternate between resistant, metastable states and resilient, transitional states. These are in turn subject
to influences of feedback loops within hydrogeomorphic and biological processes. Here we consider how resistance and resilience
largely determine HDRS ecosystem trajectories and how these characteristics can be modified by natural and anthropogenic processes.
We review the mechanisms by which biodiversity can affect both resistance and resilience and introduce a conceptual framework
that incorporates some unique HDRS characteristics. We suggest that resilient and resistant patterns frequently coexist in
the active tract of these river systems, and that this coexistance promotes the return of metastable states after major disturbances.
In contrast, highly resistant and poorly resilient patterns dominate at their external boundaries. The loss of these natural
dynamics resulting from direct and indirect human impacts causes deviations to resistance and resilience patterns and therefore
to HDRS trajectory. We propose that understanding the role of interactions between biological and physical processes that
control resistance and resilience is crucial for system restoration and management. 相似文献
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The change of frozen soil environment is evaluated by permafrost thermal stability, thermal thaw sensibility and surface landscape stability and the quantitatively evaluating model of frozen soil environment is proposed in this paper. The evaluating model of frozen soil environment is calculated by 28 ground temperature measurements along Qinghai-Xizang Highway. The relationships of thermal thaw sensibility and freezing and thawing processes and seasonally thawing depth, thermal stability and permafrost table temperature, mean annual ground temperature and seasonally thawing depth, and surface landscape stability and freezing and thawing hazards and their forming possibility are analyzed. The results show that thermal stability, thermal thaw sensibility and surface landscape stability can be used to evaluate and predict the change of frozen soil environment under human engineering action. 相似文献
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关于科技成果奖励若干问题的思析 总被引:1,自引:0,他引:1
科技成果奖励是对科技人员的一种评价。在总结实施地震科技成果奖励的管理办法与条例工作的基础上,就限额奖励、限额主要完成人的利弊,评审的方法,科技人员与管理人员的矛盾,效益证明材料等问题以及鉴定与验收的矛盾等进行了分析,提出了若干建议 相似文献
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地下岩石由岩石骨架和孔隙流体组成,通常流体含黏性.地震波在地下介质中传播时受岩石骨架和黏性流体的影响会呈现出复杂的变化.本文将流、固体位移和应力连续作为边界条件,推导出含黏性流体孔隙介质分界面上反透射系数方程;通过建立上层为饱油、下层为饱盐水的砂岩孔隙介质模型,开展反透射系数特征研究,分别分析不同频率、不同黏滞系数条件下,含黏性流体孔隙介质分界面上反透射系数随入射角的变化.研究表明,孔隙介质分界面上和等效介质分界面上的反透射系数分别随入射角的变化趋势基本一致,说明方程推导和数值计算的正确性;快纵波反透射系数受频率、流体黏性的影响较小,而快横波反透射系数在一定入射角范围内受频率、流体黏性的影响比较大;由于黏性孔隙流体的作用,慢纵波和慢横波的反透射系数受入射角、频率及流体黏性的影响都很大. 相似文献
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砂雨法是开展砂质土层和构筑物离心试验应用广泛的模型制备技术,以密实程度与均匀性为关键控制对象,直接关系试验结果的准确性和可靠性。针对砂雨装置、控制要素和均匀度测试等几个方面,概况总结了国内外离心模型砂雨法制备技术的研究进展与暴露的关键问题,归纳了现有砂雨装置的基本组成、操控特点和分类方法,阐述了稳态密实度范围及影响关键因素。综述模型空间均匀度的不同量测与评价方法,评述了各自优缺点与归一化评价标准。综合现状与不足,讨论了离心模型砂雨法制备技术的发展方向与趋势。 相似文献
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Belize Lane Irene Garousi-Nejad Melissa A. Gallagher David G. Tarboton Emad Habib 《水文研究》2021,35(7):e14273
The era of ‘big data’ promises to provide new hydrologic insights, and open web-based platforms are being developed and adopted by the hydrologic science community to harness these datasets and data services. This shift accompanies advances in hydrology education and the growth of web-based hydrology learning modules, but their capacity to utilize emerging open platforms and data services to enhance student learning through data-driven activities remains largely untapped. Given that generic equations may not easily translate into local or regional solutions, teaching students to explore how well models or equations work in particular settings or to answer specific problems using real data is essential. This article introduces an open web-based module developed to advance data-driven hydrologic process learning, targeting upper level undergraduate and early graduate students in hydrology and engineering. The module was developed and deployed on the HydroLearn open educational platform, which provides a formal pedagogical structure for developing effective problem-based learning activities. We found that data-driven learning activities utilizing collaborative open web platforms like CUAHSI HydroShare and JupyterHub to store and run computational notebooks allowed students to access and work with datasets for systems of personal interest and promoted critical evaluation of results and assumptions. Initial student feedback was generally positive, but also highlighted challenges including trouble-shooting and future-proofing difficulties and some resistance to programming and new software. Opportunities to further enhance hydrology learning include better articulating the benefits of coding and open web platforms upfront, incorporating additional user-support tools, and focusing methods and questions on implementing and adapting notebooks to explore fundamental processes rather than tools and syntax. The profound shift in the field of hydrology toward big data, open data services and reproducible research practices requires hydrology instructors to rethink traditional content delivery and focus instruction on harnessing these datasets and practices in the preparation of future hydrologists and engineers. 相似文献
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湖冰光谱特征是湖冰遥感反演的物理基础,是研究湖冰光学特性和空间分布的理论依据。本文以查干湖为例,使用ASD Field Spec 4便携式地物光谱仪采集冰封期不同类型湖冰、积雪和水体光谱,利用Savitzky-Golay滤波法和包络线去除法分析白冰、灰冰、黑冰、雪冰、积雪和水体的反射光谱特征,探索气泡对湖冰反射光谱特征的影响。积雪和雪冰、白冰和灰冰、黑冰和水体的反射特征随着波长的变化特征基本一致,冰的反射率介于积雪和水体之间,其中白冰的反射率高于灰冰和黑冰,在包络线去除结果中,黑冰和水体在440 nm吸收谷处的吸收面积为5.184和10.878、吸收深度为0.052和0.106,雪、雪冰、白冰、灰冰在800和1030 nm吸收谷处的吸收面积和吸收深度的变化表现为雪<雪冰<灰冰<白冰。气泡是影响湖冰光谱特征的重要因素,气泡使白冰反射率减小和黑冰反射率增大,并且气泡使得白冰在800/1030nm和黑冰在440 nm处的吸收面积和吸收深度减小,其中气泡大小和疏密程度的不同会导致湖冰反射率的影响程度存在差异。同时,本文选取时间同步的Landsat 8 OLI遥感影像,在完成辐... 相似文献
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Nearly 55% of Chinese GNP is out of and 70% of large-middle cities are located in the coastal regions, where there are vast plains and river-mouth deltas, covering 14% of the total land area and 40% of the nation抯 population. Since the 1980s, the coastal… 相似文献