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111.
The coupled tectonic and depositional history of extensional basins is usually described in terms of stratigraphic sequences linked with the activity of normal faults. This depositional-kinematic interplay is less understood in basins bounded by major extensional detachments or normal fault systems associated with significant exhumation of footwalls. Of particular interest is the link between tectonics and sedimentation during the migration of normal faulting in time and space across the basin. One area where such coupled depositional-kinematic history can be optimally studied is the Late Oligocene - Miocene Sarajevo-Zenica Basin, located in the Dinarides Mountains of Bosnia and Herzegovina. This intra-montane basin recorded Oligocene – Pliocene sedimentation in an endemic and isolated lake environment. We use field kinematic and sedimentological mapping in outcrops correlated with existing local and regional studies to derive a high-resolution evolutionary model of the basin. The novel results demonstrate a close correlation between moments of normal faulting and high-order sedimentological cycles, while the overall extensional basin was filled by a largely uni-directional sediment supply from the neighbouring mountain chain. The migration in time and space of listric NE-dipping normal faults was associated with a gradual shift of the sedimentological environment. Transgressive-regressive cycles reflect sequential displacements on normal faults and their footwall exhumation, defining a new sedimentological model for such basins. This Early - Middle Miocene extension affected the central part of the Dinarides and was associated with the larger opening of the neighbouring Pannonian Basin. The extension was preceded and followed by two phases of contraction. The Oligocene - Early Miocene thrusting took place during the final stages of the Dinarides collision, while the post-Middle Miocene contraction is correlated with the regional indentation of the Adriatic continental unit. This latter phase inverted the extensional basin by reactivating the inherited basal listric detachment. 相似文献
112.
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
113.
全球离散格网:回顾与展望(英文) 总被引:2,自引:0,他引:2
迈克尔F·古德切尔德 《地理与地理信息科学》2012,28(1):1-6
全球离散格网是数字球体表达的基本数据模型,它提供了一种栅格化表达地球弯曲表面的方法,催生了数字地球。该文回顾全球离散格网与数字地球的发展史,评析了以谷歌地球为代表的第一代数字地球的技术实现。在为科学界及社会公众提供地表与近地表信息交流方面,数字地球的有效性面临挑战,第一代数字地球在很多方面存在不足,其中最显著的缺陷是不能基于社会与环境过程模型模拟地球的将来状态。展望未来,简要分析了下一代数字地球应具有的基本特征。 相似文献
114.
115.
在层序地层学的Exxon时代,在强调陆上不整合面形成层序界面的概念体系中,科学家们总结认为,陆相层序形成在基准面上升期间,以一个从聚合的河道相砂岩到孤立的河道相砂岩组成的向上变细的沉积序列为特征,这代表了一个重要的概念进步;但是,运用海相层序地层的“体系域”名称,如海侵体系域和高水位体系域等,来划分和解释陆相层序的时候,又产生了若干的概念体系不协调。基于此,产生了陆相层序体系域构成的“非常规”体系域概念,成为陆相层序研究的第2个概念进步。更为重要的是,与海相地层一样,主要的沉积作用发生在基准面上升期间,但是,在基准面下降期间也可能产生相应的沉积,从而进一步说明了陆相地层复杂的堆积作用和响应机制,也表明了陆相层序更多的变化性。陆相层序的上述特征成为近年来关注的焦点之一。追逐这些概念变化和进步,将有益于深入理解陆相层序复杂的形成过程而具有重要的科学意义,同时也代表了层序地层学研究的一个重要进展。 相似文献
116.
层序地层学体系域划分的局限性--以二连盆地WL凹陷为例 总被引:3,自引:1,他引:2
陆相层序地层学的一个主要内容是将三级层序划分为“低水位体系域、湖进体系域和高水位体系域”等三个水位域沉积体系 ,分别代表着一个湖盆沉积的三个阶段。低水位体系域和高水位体系域水体较浅 ,沉积较粗 ,而湖进水位域则水体较深 ,沉积较细。长期以来 ,从国外传入的三个水位域沉积体系划分成为研究陆相沉积的经典模式。以内蒙古二连盆地 WL 凹陷为例 ,指出这种模式具有一定的局限性 ,生搬套用可能产生一些错误的认识 ,甚至直接影响研究成果的可靠性 相似文献
117.
GIS-based hydrogeological databases and groundwater modelling 总被引:4,自引:2,他引:2
Radu Gogu Guy Carabin Vincent Hallet Valerie Peters Alain Dassargues 《Hydrogeology Journal》2001,9(6):555-569
Reliability and validity of groundwater analysis strongly depend on the availability of large volumes of high-quality data.
Putting all data into a coherent and logical structure supported by a computing environment helps ensure validity and availability
and provides a powerful tool for hydrogeological studies. A hydrogeological geographic information system (GIS) database that
offers facilities for groundwater-vulnerability analysis and hydrogeological modelling has been designed in Belgium for the
Walloon region. Data from five river basins, chosen for their contrasting hydrogeological characteristics, have been included
in the database, and a set of applications that have been developed now allow further advances. Interest is growing in the
potential for integrating GIS technology and groundwater simulation models. A "loose-coupling" tool was created between the
spatial-database scheme and the groundwater numerical model interface GMS (Groundwater Modelling System). Following time and
spatial queries, the hydrogeological data stored in the database can be easily used within different groundwater numerical
models.
Electronic Publication 相似文献
118.
Keith Storey 《The Australian geographer》2001,32(2):133-148
Adoption of fly-in/fly-out (FIFO) or commute work systems in the Western Australian mining industry has increased rapidly over the last decade, with metropolitan Perth becoming the main source of labour and the base for major mining supply and service companies in the state. This situation has led to increasing concern on the part of many regional authorities about the loss of local benefits through 'fly-over' effects, and implications for regional development in their smaller resource-based communities. To date, the state government has paid little attention to these issues, but, at the same time, the regions have done relatively little to help themselves. The paper explores the reasons for the growth of this work system, the nature of the regions' concerns, the measures taken to address them, and options for future action. 相似文献
119.
集合预报系统及其产品应用综述 总被引:3,自引:0,他引:3
本文简要介绍了数值天气预报的一个重要分支——集合预报系统的研究背景,开发研究思路,集合预报产品输出的形式,集合预报输出的处理和统计解释,以及国外应用集合预报的情况。作为一项新的预报技术,集合预报将越来越受到重视。 相似文献
120.