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121.
From 1985 to 1987, four new localities with abundant fossil mammals were dis-covered by Cao, Tian and others in the Zhoukoudian (Choukoutien) area, Beijing. They are theEast, West, Shangdian and Donglingzi caves. The East Cave fauna consists of 28 speices ofmammals and its age is middle Early Pleistocene. The East Cave assemblage shows that a tem-perature-falling event took place at around 1.20 Ma B.P. at Zhoukoudian. Sixteen species ofmammals were collected from the West Cave, which are mainly forms of late Early Pleistoceneage. The West Cave fauna represents a transitional fauna from the East Cave fauna (dry-cold)to the fauna (warm) at locality 9. The Shangdian Cave fauna is composed of four forms, beingMiddle Pleistocene in age. The Donglingzi Cave fauna contains 21 Late Pleistocene forms. Inthe cave two fossil horizons may be distinguished. The age of the lower horizon is early LatePleistocene, which is equivalent to that of the New Cave fauna; while the fauna of the upper ho-rizon may be correlated with the Upper Cave fauna.  相似文献   
122.
A study has been made about the structural attribute of the NNW-trendingShizikou linear image belt in the head area of the reservoir of the Yangtze River Gorges and theevaluation of its crustal stability. On the basis of regional geological surveys and by making astructural analysis and a multidisciplinary study, it has been ascertained that the segment withthe best displayed image characteristics is marked by a gravity gliding structure with a multilay-er gliding fold type architecture. This paper also analyzes the medium conditions, slope struc-ture and dynamic setting for the formation of the structure system.  相似文献   
123.
Twenty orthosequences and their corresponding sea-level change (SLC) cycles have been recognized in the Devonian overlying the Caledonian unconformity, of which 9, 5.5 and 5.5 occurred in the Lower, Middle and Upper Devonian respectively. They can be grouped into 4 orthosequence sets, in which the maximum flooding surfaces lie in the sulcutus Zone (D12), perbonus Zone (D13), Middle and Upper varcus Zone (D22) and gigas Zone (D21) respectively. Four instant palaeogeographical reconstructions of South China have been made in the Emsian and Givetian. Devonian sea-level change rhythms of South China can be divided into 3 categories: the autorhythmic, the worldwide and regional allorhythmic, and the coupling-rhythmic. They developed respectively in the Famennian, Pragian, Eifelian, Lochkovian, Emsian, Givetian, Frasnian and the F / F (between the Frasnian and Famennian) event. The cause of the worldwide allorhythmic SLC of the Pragian and Eifelian under comparatively dry, warm and tranquil conditions may be  相似文献   
124.
A typical HP/MT (high pressure/medium temperature) eclogite from Xiongdian, northwestern Dabie Mountains, has been geochronologically studied using the single-zircon U-Pb, 40Ar-39Ar and Sm-Nd methods. Prismatic zircons occurring as inclusions within garnets define a minimum crystallization age of 399.5±1.6 Ma. 40Ar-39Ar dating on amphibole gives a plateau age.of 399.2 ± 4 Ma, which is interpreted as a retrogression age of amphibolite facies. This integrated study enables us to conclude that the age of high-pressure metamorphism is older than 399.5 ± 1.6 Ma, suggesting Caledonian collision between the North China and Yangtze plates. Round zircon within the aggregate of quartz and muscovite gives a concordant age of 301± 2 Ma, reflecting a later retrogression event. An age profile of post-eclogite metamorphism is documented, including amphibolite facies metamorphism at 399.2 Ma shortly after eclogitization and later retrogressive metamorphism at 301 Ma. Sm-Nd mineral isochron of garnet+omphacite gives  相似文献   
125.
中国石油学会物探专业委员会于1997年4月19日至24日在河南开封召开了“南方地区第八次石油物探技术研讨会”。近30个单位的代表在会上交流了各类论文共36篇。会议主要围绕南方复杂构造地区的地震勘探方法、资料采集、处理、解释和其它物探方法的应用等展开了讨论。其中,有关海相地层油气勘探技术方法研究和前景分析的部分内容如下。  相似文献   
126.
The close relationship between the genesis of coal metamorphism and the evolution of the regional tectonic framework is expounded on the basis of an analysis of the geological factors causing the metamorphic zonation of the Late Palaeozoic coals in southern North China; in terms of the mechanism for the formation of palaeogeothermal anomalies, the effects of thermal groundwater on coal metamorphism is highlighted and a geological model for thermal groundwater metamorphism of coal established; with the concept of the palaeogeotherm-coal metamorphism system, the genesis of coal metamorphism is analysed according to the distribution pattern of three geological factors: heat source, heat-carrier and channel, and heat-collector.  相似文献   
127.
地震救助生命搜索与定位技术研究进展   总被引:1,自引:0,他引:1  
生命搜索是地震紧急救援中最重要的问题,由于时间紧迫、环境条件恶劣也是最困难的问题。先进的技术与装备是提高救助成功率,最大限度减轻人员伤亡的技术保障。本文简要介绍了利用国内外目前较为成熟的相关技术,研制开发光学探生仪、声波/振动探生仪、红外热像仪3种先进、轻便、高效、实用的地震救助现场生命搜索与定位技术设备,以及利用系统工程学原理和现代管理理论,开展地震灾害现场生命搜索与救援支持系统的研究,从而初步建立地震救助生命搜索定位技术系统的基本情况。  相似文献   
128.
罗红明  朱培民 《世界地质》2004,23(2):187-191,200
地震属性是具体表征和研究地震数据内部所包含的时间、振幅、频率、相位以及衰减特性的指标。序列属性分析法作为一种地震属性数据的统计分析方法,可以使很细微的、不易被发现的统计规律会变得很明显。提取选定对比层位的序列属性参数的均值,在分别对同一属性的各层位数据排序的基础上,对各层排序情况进行总体评价,分析预测储层的含油气情况。经过与井资料反演和高阶统计量分析结果对比验证,证明了本方法储层预测的可行性。  相似文献   
129.
开合构造与岩浆活动   总被引:3,自引:0,他引:3  
邱家骧 《地质通报》2004,23(3):222-231
研究了开合构造与岩浆活动的关系。对与开合构造有关的火成岩的分类、命名、系列、组合、类型、成因进行了分析;对构造-岩浆活动的旋回进行了讨论,应用岩石地球化学图解法阐述了构造环境的演化,估算了开合作用的速度与距离;简介了中国一些地区开合构造-岩浆演化的实例。  相似文献   
130.
This paper discusses the characteristics of coal accumulation of transfor-extensional basins in linearfracture zones on the basis of an analysis of tectonic evolution and sequence stratigraphy in the Meihekou basin.Coal accumulation of the basin occurred mainly in the accelerated rifting period of the transtentional regime and inthe late period of tectonic transformation of the transpressional regime. In the former period, swamps developed inshallow lakes. The thickness of coal seams was controlled by the activity of fault block. Thick coal was formed in adownfaulted trough. In the latter period, swamps developed in a braided fan delta plain. The coal seams are thin andhave poor lateral continuity. The thickness of coal seams was controlled by the migration of water channels in thebraided plain.  相似文献   
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