Collaborative Research: Tectonics and Topography in the Transverse Ranges: Landscape Response to Rock Uplift Rate across the Transition from Soil-Mantled to Rocky Slopes

这项研究是在圣盖博山脉进行的一项为期三年的合作研究，旨在系统地研究在从土壤覆盖的、蠕变和瑞波主导的山坡到岩石、基岩滑坡主导的山坡的关键转变过程中，山坡和河道对岩石隆升率增加的反应。已发表的数据和初步的地形分析以及河流沉积物中宇宙成因10Be的测量结果表明：(1)侵蚀速率在0.1至= 1 km/Ma的范围内系统地变化；(2)碎屑宇宙成因10Be是该景观中有效的侵蚀速率监测仪。圣盖博山脉在相对统一的岩性和气候条件下（具有已知的地形降雨模式），从西到东的侵蚀速率系统变化，为回答景观演变中的几个关键问题提供了前所未有的机会。将测试六个具体的可测试的假设，这些假设对于进一步发展对构造和地形之间关系的定量理解至关重要，并确定一套具体的实地地点和方法，这些地点和方法应该对这些假设进行明确的测试，并对潜在过程进行量化。这项工作的广泛影响跨越了用于促进扩展研究范围的五个一般NSF标准。从根本上说，这个项目符合我们的主要教育目标：将实地研究融入不同受众的教育中，进一步加深他们对地球表面过程的理解，并帮助弥合理论与应用以及科学与政策之间的差距。

This study is a three-year collaborative research effort in the San Gabriel Mountains to systematically study both hillslope and channel response to increasing rock uplift rate across the critical transition from soil-mantled, creep- and ravel-dominated hillslopes to rocky, bedrock landslide-dominated hillslopes. Published data and preliminary topographic analyses coupled with measurements of cosmogenic 10Be in river sediments demonstrate that (1) erosion rates vary systematically throughout the range from 0.1 to = 1 km/Ma, and (2) detrital cosmogenic 10Be is an effective erosion-rate monitor in this landscape. The systematic west-to-east variation in erosion rate with relatively uniform lithologic and climatic conditions (with a known orographic rainfall pattern) in the San Gabriel Mountains affords an unprecedented opportunity to answer several key questions in landscape evolution. Six specific testable hypotheses that are critical to further development of a quantitative understanding of the relationship between tectonics and topography will be tested, and a specific suite of field sites and methods are identified that should yield definitive tests of these hypotheses as well as quantification of the underlying processes. Broader impacts of this work span the five general NSF criteria used to promote extending the reach of the research. Fundamentally, this project fits into our main educational objective: to integrate field studies into the education of diverse audiences, furthering their understanding of Earth surface processes and helping to bridge the gaps between theory and application as well as science and policy.