...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Asian earth sciences >Carbonatites in China: A review
【24h】

Carbonatites in China: A review

机译：中国的碳酸盐岩：回顾

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

There are 27 known occurrences of carbonatites in China. Brief descriptions are given of all occurrences including geographical coordinates, geological setting, associated rocks, carbonatite forms, ages, mineralogy, mineralisation, and carbon and oxygen isotopic data. About half of the occurrences lie along the margins of orogenic belts and the rest close to the margins and within tectonic blocks. All appear to be located on, or near to, major intraplate fractures. All the major carbonatite types are represented, including major complexes associated with alkaline silicate rocks such as ijolite, nepheline syenite, etc. several comprising dyke swarms, with or without associated silicate rocks, and extrusive carbonatite complexes. Several of the occurrences that are interpreted as being extrusive are problematic, three of these being Proterozoic in age and having field relationships which are difficult to interpret. Nineteen carbonatites have been dated and 15 of these give dates lying in the range 4-265 Ma. Two occurrences give Proterozoic dates, but a further three undated occurrences are considered to be Proterozoic, based on their field relationships. Dating of the Bayan Obo complex indicates emplacement of carbonatite dykes at 2070 Ma, but the complex appears to have been affected by four subsequent periods of mineralisation. Three occurrences are being mined for REE, and Fe, P and vermiculite are also being produced.
机译：在中国有27个已知的碳酸盐岩。简要描述了所有发生的事件，包括地理坐标，地质环境，相关的岩石，碳酸盐岩形式，年龄，矿物学，矿化作用以及碳和氧同位素数据。大约一半的事件发生在造山带边缘，其余的靠近边缘并在构造块内。所有这些都似乎位于或严重的板内骨折附近。代表了所有主要的碳酸盐类型，包括与碱性硅酸盐岩石有关的主要配合物，如ijolite，霞石正长岩等。若干包括堤群，有或没有相关的硅酸盐岩石，以及挤出的碳酸盐配合物。某些被解释为是挤压性的事件是有问题的，其中三个在年龄上是元古代的，并且具有难以解释的场关系。已有19个碳酸盐岩定年，其中15个碳酸盐岩定年在4-265 Ma之内。有两个事件给出了元古代的日期，但根据它们的田间关系，又有三个未注明日期的事件被认为是元古代的。 Bayan Obo复合体的年代表明碳酸盐岩堤坝在2070 Ma时就位，但该复合体似乎已受到随后四个成矿期的影响。正在开采三处稀土矿，也正在生产铁，磷和ver石。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号