...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Geochemistry, geophysics, geosystems >Emergence/Subsidence Histories Along the Carnegie and Cocos Ridges and Their Bearing Upon Biological Speciation in the Galápagos
【24h】

Emergence/Subsidence Histories Along the Carnegie and Cocos Ridges and Their Bearing Upon Biological Speciation in the Galápagos

机译：沿着卡内基和Cocos山脊的出现/沉降历史及其在Galápagos的生物学形态的轴承

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

Using plate motion reconstructions for the Nazca, Cocos, and South American plates in relation to the Galápagos hotspot, we find that age-depth dependence of bathymetry, Galápagos plume dynamic topography, crustal relaxation, and magmatic production permit reasonable estimates for the subsidence of former islands along the Carnegie and Cocos Ridges. Our dynamic topography estimates are partially based upon geodynamic theory (fluidmechanics and elasticity) and also upon detailed bathymetric observations and analysis. For three different target areas over Carnegie Ridge and two over Cocos Ridge, we infer subaerial landmasses over the past ~20 Ma.We provide rough estimates of the surface areas of these paleo-archipelagos, which were comparable to that of the present-day Galápagos archipelago. We construct a history of emerged (paleo-island) topography along the conjugate pair Carnegie-Cocos hotspot tracks and infer that significant subaerial landscapes existed for at least the past ~20 Ma. The genetic ancestors of endemic faunal species in Galápagos (e.g., marine iguanas) migrated away from South America, genetically diverging from their land counterpartsmuch earlier than the age of the present Galápagos Islands (~3Ma). At 16.5Ma, the total emerged landmass on the Carnegie Ridge alone may have been ~2.5 times that of the current Galápagos archipelago. (The conjugate landmass along the Cocos Ridge has been subducted.) We propose that this large landmass, at least one-fourth the size of Iceland, be called Darwinia in recognition of its importance in the evolution of some Galápagos endemic flora and fauna made famous by Darwin's explorations. Summary Using reconstructed motions of the Nazca, Cocos, and South American tectonic plates with respect to the upwelling Galápagos mantle plume (hotspot), we studied the regional mechanical and thermal evolution of the crust and lithosphere. Using the theory of viscous fluids, elastic solids, and thermodynamics, and consider
机译：利用纳斯卡，Cocos和南美板的板式运动重建与Galápagos热点有关，我们发现年龄深度依赖性的沐浴池，Galápagos羽毛动态地形，地壳放松和岩浆生产允许合理的估计为前者的沉降沿着卡内基和Cocos山脊的岛屿。我们的动态地形估计部分基于地磁理论（流体机械和弹性）以及详细的碱基观察和分析。对于Carnegie Ridge的三个不同的目标区域和两个穿过Cocos Ridge，我们在过去〜20 ma的底座陆地上推断出底座陆地。我们提供了这些古群岛的表面区域的粗略估计，其与本今Galápagos相当群岛。我们构建沿共轭对Carnegie-Cocos热点轨道的出现（Paleo-Island）地形的历史，并推断至少过去〜20 mA存在显着的血管景观。生殖病群的遗传祖先在Galápagos（例如海洋鬣蜥）迁移远离南美洲，遗传地从他们的土地对应于目前的Galápagos群岛（〜3mA）的年龄差异。在16.5mA，仅仅是Carnegie Ridge上的总陆地可能是当前Galápagos群岛的2.5倍。 （沿着Cocos Ridge的共轭地陆地已经被压制了。）我们建议这一大型陆地，至少四分之一的冰岛大小，被称为达尔文尼亚，以认识到其在一些Galápagos流行病群和动物群中的重要性由达尔文的探索。总结使用Nazca，Cocos和南美构造板的重建动作以及升起的Galápagos地幔羽流（热点），我们研究了地壳和岩石圈的区域机械和热演变。使用粘性液体理论，弹性固体和热力学，并考虑

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