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91.
齐永安  胡斌 《沉积学报》1998,16(1):22-26
在层序地层学研究中,海进(transgrssion)常被认为是快速形成的,序列简单,并以少量沉积为特征。对塔里木盆地下志留统塔塔埃尔塔格组痕迹化石及沉积特征研究表明,海进期沉积及海进体系域比人们想象的要复杂,由三类沉积组成:(1)与海进侵蚀有关,包括海进滞留沉积,发育固底控制Glossifungites痕迹相;(2)与海进初期的海面缓慢上升或总体海进过程中的静止期有关,包括前滨和临滨砂泥岩,发育Skolithos痕迹相和近端Gruziana痕迹相;(3)与海面快速上升有关,包括滨外泥岩,发育远端Gruziana痕迹相。  相似文献   
92.
本文在分析断陷湖盆陡坡带不同构造部位的可容空间变化规律及其沉积响应特征的基础上,探讨了断陷湖盆陡坡带参照井选取的可容空间机理,并阐明了参照井的选择原则;根据参照井处的沉积相迁移特征及体系域叠置样式,建立了在参照井的背景下,Ⅰ型与Ⅱ型陆相层序划分及其层序界面判识的标准,以及低水位体系域(LST)、水进体系域(TST)、高水位体系域(HST)及水退体系域(RST)的识别模式。本文以泌阳断陷双河~赵凹地区下第三系核三上段为例,采用泌207井为参照井,对研究区目的层段开展了断陷湖盆陡坡带陆相层序地层学的尝试性研究,并编制了研究区目的层段的陆相层序地层等时框架模式。研究结果表明,采用选取参照井的办法,可以有效地解决断陷湖盆陡坡带陆相层序地层分析中的“沉积滨线坡折”问题。  相似文献   
93.
右江盆地层序充填动力学初探   总被引:21,自引:4,他引:21  
在盆地分析及层序地层研究成果基础上,采用层序 -盆地 -地球系统的动态成因分析方法,对右江盆地进行了初步的层序充填动力学研究。首次识别出 5个级别的层序界面及相应的沉积层序,讨论了层序界面与地质事件、层序级别与盆地类型等的关系,进而建立了右江盆地层序地层格架。通过对裂谷盆地层序发育明显受同沉积断裂及基底沉降控制的分析,建立了层序成因与盆地构造活动的关系模型。在此基础上,探讨了层序充填动力学过程及其与盆地演化的关系。右江盆地层序充填过程包括陆内裂陷、陆缘裂谷、弧后裂谷和前陆造山四个阶段,经历了海西 -印支期由拉张到挤压的完整构造旋回。  相似文献   
94.
歧北凹陷沙河街组层序地层学研究   总被引:6,自引:2,他引:6  
吴元燕  刘震 《沉积学报》1996,14(1):167-175
本文从地震、古生物、沉积和测井等多方面的资料入手,用层序地层学方法研究了黄骅坳陷歧北凹陷沙河街组的地层层序,将其划分为两个大层序,即层序Ⅰ(沙三段)和层序Ⅱ(沙二、沙一段)。在每个层序中,又进一步划分出低位、湖进和高位三个体系域,总结了各个体系域的特征,进而指出有利的油气聚集相带和地段。  相似文献   
95.
Chemometrics is defined as the application of mathematical and statistical methods to chemical systems.Systems theory is seen to be useful for organizing and categorizing the inputs to and outputs fromchemical systems.Advances in measurement science in the 1950s and 1960s,particularly in analyticalchemistry,created a need for a multivariate approach to data analysis.Early chemometrics emphasizedthe use of structure-finding methods for existing data sets.In many instances,data sets can be obtainedfrom designed experiments.Such data sets are more likely to contain the desired information and the datacan usually be acquired at less cost.Renewed interest in statistical process control will provide many new,more robust data sets in the future.  相似文献   
96.
从生产资产到生态资产:资产—资本完备性   总被引:9,自引:0,他引:9  
胡聃 《地球科学进展》2004,19(2):289-295
本研究探讨从生产资产(produc edassets)到生态资产的完备化理论。其内容主要包括:资产-资本完备化;生态资产定义、构成、分类与比较;经济权与完备化,为该研究的第一部分内容。首先,回顾了国内外环境、资源与生态经济学领域有关资产和资本的研究概况,指出当前该领域的前沿热点之一是从生产资产走向生态资产的综合与系统化,这一发展趋势突出体现在关于资产-资本的完备化研究。通过简要地分析新古典经济学中资产和资本范畴的局限性及其所产生的不完备性,总结出其主要表现是概念不完备性、价值不完备性和权义不完备性,而价值不完备性是当前研究的核心问题。在此基础上,进一步评述了现代经济学在资产或资本完备化研究中所取得的重要进展及有待解决的重大问题。该文从系统学意义上提出,推出完备化过程首先需要建立系统资产和资本概念,并进一步讨论了系统资产和资本的基本内涵,提出了资产-资本完备化的 5个法则。  相似文献   
97.
Underwater acoustic technologies may be used for remote sensing of estuarine and coastal benthic habitat in addition to more traditional methods of assessing the seabed. These systems use reflected sound energy to identify surface objects, texture, and subbottom density discontinuities, and to classify benthic habitat. We evaluated the ability of subbottom profiling systems, side scan sonar, and acoustic seabed classification systems (ASCS) to assess oyster habitat in the Chesapeake Bay. Our criteria were the systems' abilities to assess the quality and quantity of oyster shell resources and to integrate with Geographical Information Systems (GIS) technology for the charting of the seabed. Although all systems examined have previously been used for benthic habitat assessment, we found that ASCS offered the most promise as a stand alone system for mapping complex and heterogeneous habitat typical of oyster bottoms. The results from this study suggest that ASCS technology is highly suited for the identification and charting of oyster shell as well as distinguishing among different combinations of shell and fine sediments. Such systems also offer excellent linkage with GIS display and analysis capability.  相似文献   
98.
Environmental Prognostics is proposed as an integrated explanatory framework for adverse changes in whole systems, from cells to animals to ecosystems. The aim is to develop such frameworks for the evaluation of "health of the environment" and prediction of consequences resulting from future environmental events based on integrating the reactions of biomarkers for cellular and physiological processes, through conceptual, statistical and computational modelling. These are urgently needed to synthesise complex information on environmental chemistry and injurious effects of pollutants into predicted harmful impact on health of sentinel animals.  相似文献   
99.
Traditional agricultural heritage research has a very long history. Programme on “The conservation and adaptive management of Globally Important Agricultural Heritage Systems (GIAHS)” initiative launched by FAO in 2002, aimed at not only preserving agricultural heritage system, but also applying the principle of dynamic conservation to promote rural development to benefit local community, to assure food security and maintaining the ecosystem. Since then, many more scientists have been enrolled in the new field focusing on the function and value, application and management, conservation and development and other aspects of these traditional agricultural systems which facilitate an emerging cross-discipline. In this paper, based on the concepts and characteristics of GIAHS and China Nationally Important Agricultural Heritage Systems (China-NIAHS), the author specifies that Agri-cultural Heritage is a compound heritage that integrates the characteristics of natural, cultural and intangible cultural heritage, and a typical social-economic-natural complex ecosystem composed of economic, biological, technological, cultural and landscape components. For their conservation and development, the joint efforts of scientists from economics, ecology, geography, history, management sciences, culturology, ethnology, sociology and other subjects are needed. Based on progresses studies and perspectives of the field, the author felt that although a good start of the research on Agri-cultural Heritage has been made, there is still much room for development which show a steady growth trend and suggested 32 priority areas in research; a new subject of Agroheritology could emerge in the near future.  相似文献   
100.
An assessment of gully erosion along road drainage-release sites is critical for understanding the contribution of roads to soil loss and for informed land management practices. Considering that road-related gully erosion has traditionally been measured using field methods that are expensive, tedious and limited spatially as well as temporally, it is important to identify affordable, timely and robust methods that can be used to effectively map and estimate the volume of gullies along the road networks. In this study, gullies along major roads were identified from remotely sensed data sets and their volumes were estimated in a Geographic Information Systems environment. Also, the biophysical and climatic factors such as vegetation cover, the road contributing surface area, the gradient of the discharge hillslope and rainfall were derived from remotely sensed data sets using Geographic Information Systems techniques to find out whether they could explain the morphology of gullies that existed in this area. The results of this study indicate that hillslope gradient (R2?=?0.69, α = 0.00) and road contributing surface area (R2?=?0.63, α = 0.00) have a strong influence on the volume of gullies along the major roads in the south-eastern region of South Africa, as might have been expected. However, other factors such as vegetation cover (R2 = 0.52, α = 0.00) and rainfall (R2 = 0.41 and α = 0.58) have a moderately weaker influence on the overall volume of gullies. Overall, the findings of this study highlight the importance of using remote sensing and Geographic Information Systems technologies in investigating gully erosion occurrence along major roads where detailed field work remains a challenge.  相似文献   
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