首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2篇
  免费   0篇
测绘学   1篇
地质学   1篇
  2017年   1篇
  2002年   1篇
排序方式: 共有2条查询结果,搜索用时 62 毫秒
1
1.
A petrological study was carried out on Mg-skarn-bearing dunitecumulates that are part of the Neo-Proterozoic Ioko-Dovyrenintrusion (North Baikal region, Russia). Skarn xenoliths containbrucite pseudomorphs after periclase, forsterite and Cr-poorspinel. Fine-grained forsterite–spinel skarns occur withthe brucite skarns or as isolated schlieren. Field relationshipsreveal that the Mg-skarns formed from silica-poor dolomiticxenoliths by interaction with the mafic magma of the Ioko-Dovyrenintrusion. Rapid heating of dolomitic xenoliths by the maficmagma caused the decomposition of dolomite into calcite + periclase,releasing much CO2. Further heating quantitatively melted thecalcite. A periclase-rich restite was left behind after extractionof the low-density, low-viscosity calcite melt. The extractedcalcite melt mixed with the surrounding mafic melt. This resultedin crystallization of olivine with CaO contents up to 1·67wt %. A local decrease in the silica concentration stabilizedCaAl2SiO6-rich clinopyroxene. Brucite/periclase-free forsterite–spinelskarns probably originated by crystallization from the maficmelt close to the xenoliths at elevated fO2. The high fO2 wascaused by CO2-rich fluids released during the decompositionof the xenoliths. The above case study provides the first evidencefor partial melting of dolomite xenoliths during incorporationby a mafic magma. KEY WORDS: dunite; dolomite assimilation; partial melting  相似文献   
2.
针对摄影测量三维建模向全自动化发展的背景,该文基于SURE摄影测量软件,实现了自动化建立三维场景。阐述了主要的处理环节,包括密集匹配、平差交会、三角构网及贴图等,可生产的产品包括密集点云、真正射影像、数字表面模型、不规则三角网及三维贴图场景;通过分析匹配效率及点云和数字表面模型的精度,显示出其产品均可达到测量级精度。使用高重叠度或倾斜影像,SURE还可以生产出精美的三维城市模型;充分挖掘每一个像素的高精度三维坐标,是其在同类软件中的一大特色。  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号