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x随着GIS在地质中的应用，地质GIS数据模型在几何描述与表达方面日趋完善，但是对地质构造现象的语义描述与表达却较为有限，制约了地质研究者对地质GIS地理解与应用。为了增强地质GIS数据模型中的语义信息，本文采用面向对象的方法，通过地质对象来统一描述和表达地质构造现象的几何与语义特征，设计了几何与语义统一的区域地质构造GIS数据模型。本文设计了基于＂词汇概念-名词解释-几何图例＂的地质构造现象的语义三角描述方法。依据区域地质构造的语义特征，采用线性分类法将区域地质构造现象划分为3个大类、10个中类和33个小类，在此基础上定义了地质构造现象的基本要素集和要素类，并基于地质对象之间的几何和语义关系，建立了区域地质构造现象要素的基本几何网络。采用ArcGIS Diagrammer Geodatabase建模工具，构建了几何与语义统一的地质GIS数据模型。最后，以宁镇山脉区域地质构造现象为例对该数据模型进行了试验验证，结果表明该模型具有较好的实用性。

The Neogene sediments of Gansu Group from northwestern China contain eolian and fluvial deposits. The origins of these sediments are very important for exploring the onset of Asian inland aridification, the pattern of paleo-atmospheric circulation, and the regional tectonics and geomorphic evolution during the Miocene. Here we present detrital-zircon age spectra of typical eolian and fluvial deposits from highlands and subsidence basin, and compare them with those of surrounding eroded mountain（such as the West Qinling Mountains and Liupan Mountains） materials and Quaternary loess derived from the Asian inlands. The results reveal that（1） the detrital-zircon age spectrum of the Miocene eolian sample is remarkably different from the eroded materials of the West Qinling Mountains and the Miocene fluvial deposits from Tianshui region, but very similar to the Quaternary loess deposits. This indicates that the provenance of Miocene eolian sediments is similar with the Quaternary loess, and thus further confirms the previous conclusions that the distribution of Asian arid lands and the pattern of atmospheric circulation during the Miocene are broadly similar with the Quaternary.（2） The detrital-zircon age spectrum of the fluvial deposits（with age about 11.5 Ma） from Tianshui region is different from the eroded materials of West Qinling Mountains, but similar with that of the Liupan Mountains to the east, which may suggest that the Liupan Mountains have already been exhumed by 11.5 Ma.

Guizhou （贵州） Province, Southwest China, is rich in coalbed methane （CBM） resources, wherein its geological structure is complicated. We discuss the occurrence characteristics of CBM based on CBM borehole test data and geological setting. In combination with the analysis of the regional tectonics, macro-and micro-scopic geological structures and pore size distributions, the structural controls on CBM reservoirs were further discussed from the aspects involving tectonic evolution, structural features, and deformation of coal. The results show that the CBM enrichment was mainly controlled by the regional tectonic subsidence and weak structural deformation on coal reservoirs after coal formation. The Yangmeishu （杨梅树） syncline and topography are the main controlling factors to the current distribution pattern of CBM, which is higher in the north than the south and trending toward the NE direction. Normal faults and fractures can be divided into open, closed, and occluded types. The open type reduces both gas content and methane concentration of nearby coal seams. The closed type causes the decrease of gas content, while methane concentration is still high. The occluded type fail to reduces gas content, and even results in the enrichment of CBM in small areas near fault. Moderate brittle deformation can improve the pore structure and development of structural fracture of coal reservoir.Cataclastic structural coals with well-developed fractures and relatively uniformly distributed pore structures are common in the Faer （发耳） coal mine, which are favorable for the production of CBM.

欧亚北极地区西部,西起北大西洋东岸,东至上扬斯克山脉,区域地质构造复杂。根据其构造特征,以乌拉尔-新地岛-泰梅尔造山带为界,可以分为东西两区。西区主要构造单元包括前寒武纪的波罗的克拉通与斯瓦尔巴微板块以及蒂曼造山带、加里东造山带和乌拉尔-新地岛造山带等,而东区主要包括西伯利亚克拉通及上扬斯克造山带。本区主要经历4次大的构造事件:(1)新元古代至早寒武世的蒂曼造山运动,使得波罗的古陆与斯瓦尔巴-喀拉微板块碰撞造山,形成蒂曼造山带;(2)早古生代,奥陶纪-志留纪的加里东造山运动,使波罗的与劳伦碰撞造山,形成加里东造山带;(3)晚古生代,哈萨克斯坦板块与波罗的古陆与西伯利亚古陆的碰撞,形成乌拉尔-新地岛-泰梅尔造山带;(4)早白垩世,科雷马-奥莫隆复合超地体及阿拉斯加-楚科塔微板块与西伯利亚大陆边缘碰撞拼贴,形成上扬斯克造山带和南阿纽伊缝合线。

The geometry and timing of amalgamation of the North China craton（NCC） have been controversial,with three main models with significantly different interpretations of regional structure,geochronology,and geological relationships.The model of Zhao G C et al.suggests that the eastern and western blocks of the NCC formed separately in the Archean,and an active margin was developed on the eastern block between 2.5 and 1.85 Ga,when the two blocks collided above an east dipping subduc-tion zone.The model of Kusky et al.presumes that the eastern block rifted from an unknown larger continent at circa 2.7 Ga,and experienced a collision with an arc（perhaps attached to the western block） above a west-dipping subduction zone at 2.5 Ga,and the 1.85 Ga metamorphism is related to a collision along the northern margin of the craton when the NCC joined the Columbia supercontinent.The model of Faure et al.suggests two collisions in the central orogenic belt,at 2.1 and 1.88 Ga.Recent seismic results support both the models of Ku