The Palaeozoic tectono-metallogenic evolution of the northern Tasman Fold Belt System, Australia: Interplay of subduction rollback and accretion     

I.M.A. Vos  F.P. Bierlein  D. Phillips 《Ore Geology Reviews》2007,30(3-4):277-296

The Tasman Fold Belt System in eastern Australia provides a record of the Palaeozoic geological history and growth of the Australian continent along the proto-Pacific margin of Gondwana inboard of an extensive and long-lived subduction system. The Hodgkinson and Broken River provinces represent prominent geological elements of this system and together form the northern Tasman Fold Belt System. Geochronological age dating of the timing of gold formation in the Amanda Bel Goldfield in the Broken River Province and the Hodgkinson Goldfield in the Hodgkinson Province provides constraints on the occurrence of a deformation and mineralisation episode in the Late Devonian–Early Carboniferous. Integration of these newly-obtained data with petrogenetic constraints and a time–space evaluation of the geological evolution of the Hodgkinson and Broken River provinces, as well as other terranes in the northern Tasman Fold Belt System, allows for the development of a geodynamic model for the Palaeozoic evolution of the northern Tasman Fold Belt System. Our model indicates that three cycles of extension–contraction occurred during the Palaeozoic evolution of the northern Tasman Fold Belt System. Episodes of extension were controlled by rollback of the subduction system along the proto-Pacific margin of Gondwana, whereas episodes of contraction resulted from accretion following the arrival of positively buoyant segments (i.e., micro-continental blocks/oceanic plateaus) at the subducting trench.Our composite interpretative model on the geodynamic evolution of the northern Tasman Fold Belt System integrates the timing of the development of mineral deposits throughout this part of the system and provides a significant advancement in the understanding of Palaeozoic geodynamics along the margin of Gondwana in northeast Australia and allows comparison with the southern part of the Tasman Fold Belt System.  相似文献   

北方落叶果树嫁接适宜气象条件调查与研究     

赵变茂  贺延梅  李化龙 《陕西气象》2007,(4):30-31

本文介绍了山西省气象局气象科技数字图书馆的构架及服务功能，从数字图书馆技术方面分析了气象科技图书馆的主要特点，同时对数字图书馆开通以来的使用情况进行了统计分析，为数字图书馆的进一步完善和发展提出构想。  相似文献   

广西中尺度数值模式格点产品检验系统     

刘泽军黄嘉宏  林振敏 《广西气象》2007,28(4):34-36

根据WMO规定的数值预报标准化检验方案开发的数值预报格点产品检验系统,可以实时检验广西中尺度数值预报产品及9210下发的多种数值产品,可为数值模式的改进及数值产品的业务化应用提供直接的参考依据。  相似文献   

Testing satellite and ground thermal imaging of low-temperature fumarolic fields: The dormant Nisyros Volcano (Greece)   总被引：1，自引：0，他引：1  

E. Lagios  S. Vassilopoulou  V. Sakkas  V. Dietrich  B.N. Damiata  A. Ganas 《ISPRS Journal of Photogrammetry and Remote Sensing》2007,62(6):447-460

The Nisyros Volcano (Greece) was monitored by satellite and ground thermal imaging during the period 2000–2002. Three night-scheduled Landsat-7 ETM⁺ thermal (band 6) images of Nisyros Island were processed to obtain land surface temperature. Ground temperature data were also collected during one of the satellite overpasses. Processed results involving orthorectification and 3-D atmospheric correction clearly show the existence of a thermal anomaly inside the Nisyros Caldera. This anomaly is associated mainly with the largest hydrothermal craters and has land surface temperatures 5–10 °C warmer than its surroundings. The ground temperature generally increased by about 4 °C inside the main crater over the period 2000–2002. Ground thermal images of the hydrothermal Stephanos Crater were also collected in 2002 using a portable thermal infrared camera. These images were calibrated to ground temperature data and orthorectified. A difference of about 0–2 °C was observed between the ground thermal images and the ground temperature data. The overall study demonstrates that satellite remote sensing of low-temperature fumarolic fields within calderas can provide a reliable long-term monitoring tool of dormant volcanoes that have the potential to reactivate. Similarly, a portable thermo-imager can easily be deployed for real-time monitoring using telemetric data transfer. The operational costs for both systems are relatively low for an early warning system.  相似文献   

GPS应用于垂直位移监测的方案设计及数据处理方法     

莫乃鹤  李向新 《国土资源信息化》2007,(2):28-30

本文主要研究了GPS变形监测中垂直位移的问题。通过对误差分析,建立GPS大地高高差平差模型,以便提高GPS变形监测在垂直位移方向上的精度。从而真正的达到GPS三维监测。  相似文献   

省级国土资源管理信息化发展研究     

岳建伟  李京 《国土资源信息化》2007,2(4):9-12

本文在对当前国土资源信息化存在的问题分析的基础上,提出进行数据整合、可复用构件提取、业务整合、登录门户整合、建立标准、在对国土资源信息化现状调查和对未来信息化发展趋势分析的基础上制定中远期发展规划和相应的具体实施方案来解决这些问题。  相似文献   

恒星干涉仪星光方向矫正伺服系统     

王正明  李再雄 《时间频率学报》1998,21(1):65-73

恒星干涉仪的关键技术之一是用自适应光学技术来调节两相干光束之间的夹角,以保证干涉条纹可见度的损失最小。在我们的恒星干涉仪实验系统中,光束方向矫正系统就是为这一目的而研制的．该系统中的光子计数系统和8098单板机的软、硬件组成了补偿光束方向随大气扰动而变的系统．文章介绍了该伺服系统以及在实验系统联调时的试验结果。  相似文献   

关于建立我国卫星电视授时系统的方案   总被引：2，自引：1，他引：1  

宋金安 《时间频率学报》1998,21(2):1-4

提出搭载现存的卫星TV广播系统进行高精度授时的方案,改进和提高我国的授时服务。该方案与现存的短波、长波授时比较,有许多优点：精度高、复盖面大、用户设备简单,能24小时连续服务,并包含有更多的时间信息、自动定时和输出标准频率。2～3年就能建成本系统．即可以投入使用,且投资很少。  相似文献   

GIS面向用户的模型库及其管理系统的设计与实现——以GIS中地形分析为例     

王卉 《测绘学院学报》1998,(3)

主要阐述了 GIS中模型库及其管理系统的基本概况 ,介绍了在 Windows 95环境下 ,用动态连接库 (DLL)实现模型的存储 ,用面向用户的方式实现模型维护的一种方法 ,并以此为基础建立了军事地形分析模型库。  相似文献   

开放数据库互联与地理信息系统   总被引：1，自引：0，他引：1  

吴升  王家耀 《测绘学院学报》1998,(3)

论述了开放数据库互联的基本原理 ,从技术角度探讨了在地理信息系统中应用开放数据库互联技术的实际价值 ,并建立了一个在客户 /服务器模式下两者集成的可行性模型。  相似文献