...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth and Planetary Science Letters: A Letter Journal Devoted to the Development in Time of the Earth and Planetary System >Canyon incision and knickpoint propagation recorded by apatite He-4/He-3 thermochronometry
【24h】

Canyon incision and knickpoint propagation recorded by apatite He-4/He-3 thermochronometry

机译：磷灰石He-4 / He-3热年代计记录的峡谷切口和拐点传播

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

In many regions of the world, deeply incised canyons demonstrate the net effects of physical processes active at Earth's surface in response to surface uplift. Low-temperature thermochronometry can constrain the timing and rates of bedrock incision, which is necessary for relating canyon incision to surface uplift over geological timescales. We analyzed four samples from the Cotahuasi-Ocona canyon system in southwest Peru using He-4/He-3 thermochronometry and we present a new inversion model to identify continuous low-temperature cooling histories that are consistent with the observed data. Derived cooling histories limit the onset of fluvial incision to similar to 13 to 8 Ma. This is in agreement with previously reported interpretations based on a three-dimensional thermal model interpolation to a much larger set of conventional apatite (U-Th)/He ages. However, because He-4/He-3 thermochronometry constrains an independent cooling history for each sample, the results also permit testing of landscape-evolution models with greater spatial variability in exhumation compared to those models that can be tested by a geographically scattered set of conventional (U-Th)/He ages. The different cooling histories of the four samples require asynchronous incision along at least part of the canyon system that is best explained by headward propagation of fluvial incision by knickpoint migration.
机译：在世界许多地区，深切的峡谷显示了响应地表抬升而活跃在地球表面的物理过程的净效应。低温测温法可以限制基岩切开的时间和速率，这对于将峡谷切开与地质时标上的地面隆起联系​​起来是必不可少的。我们使用He-4 / He-3热年代计分析了秘鲁西南部Cotahuasi-Ocona峡谷系统的四个样本，并提出了一个新的反演模型，以识别与观测数据一致的连续低温降温历史。导出的冷却历史将河流切口的发作限制在大约13至8 Ma。这与先前报道的基于三维热模型插值的解释相一致，该三维热模型插值用于更大范围的常规磷灰石（U-Th）/ He年龄。但是，由于He-4 / He-3热计时法为每个样品限制了独立的冷却历史，因此与可以通过地理上分散的一组检验的那些模型相比，结果还允许在挖掘中具有更大空间变异性的景观演化模型进行试验。传统（U-Th）/ He年龄。四个样品的冷却历史不同，需要沿峡谷系统的至少一部分进行异步切割，这最好通过用拐点移动引起的河道切口向前方传播来最好地解释。

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