• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Astrobiology >Iron-Magnesium Silicate Bioweathering on Earth (and Mars?)
【24h】

Iron-Magnesium Silicate Bioweathering on Earth (and Mars?)

机译：铁镁硅酸盐生物风化在地球上（还有火星？）

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

We examined the common, iron-magnesium silicate minerals olivine and pyroxene in basalt and in mantle rocks to determine if they exhibit textures similar to bioweathering textures found in glass. Our results show that weathering in olivine may occur as long, narrow tunnels (1-3 μm in diameter and up to 100 μm long) and as larger irregular galleries, both of which have distinctive characteristics consistent with biological activity. These weathering textures are associated with clay mineral by-products and nucleic acids. We also examined olivine and pyroxene in martian meteorites, some of which experienced preterrestrial aqueous alteration. Some olivines and pyroxenes in the martian meteorite Nakhla were found to contain tunnels that are similar in size and shape to tunnels in terrestrial iron-magnesium silicates that contain nucleic acids. Though the tunnels found in Nakhla are similar to the biosig-natures found in terrestrial minerals, their presence cannot be used to prove that the martian alteration features had a biogenic origin. The abundance and wide distribution of olivine and pyroxene on Earth and in the Solar System make bioweathering features in these minerals potentially important new biosignatures that may play a significant role in evaluating whether life ever existed on Mars.
机译：我们检查了玄武岩和地幔岩石中常见的铁镁硅酸盐矿物橄榄石和辉石，以确定它们是否表现出类似于玻璃中发现的生物风化纹理。我们的结果表明，橄榄石的风化可能会发生在狭窄的长隧道（直径为1-3μm，最长可达100μm）和较大的不规则画廊中，这两者都具有与生物活性一致的独特特征。这些风化质地与粘土矿物副产物和核酸有关。我们还检查了火星陨石中的橄榄石和辉石，其中一些经历了陆地前的水相变化。发现火星陨石纳赫拉中的一些橄榄石和辉石的隧道在大小和形状上与包含核酸的陆地铁镁硅酸盐中的隧道相似。尽管在纳赫拉（Nakhla）发现的隧道与在陆地矿物中发现的生物特征相​​似，但是它们的存在不能用来证明火星蚀变特征具有生物成因。地球和太阳系中橄榄石和辉石的丰富和广泛分布使这些矿物质的生物风化特征成为潜在的重要新生物特征，可能在评估火星上是否存在生命方面发挥重要作用。

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