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

这项研究是在圣加布里埃尔山脉进行的一项为期三年的合作研究工作，旨在系统地研究从土壤覆盖的蠕变和拉威尔主导的山坡到岩石基岩滑坡主导的山坡的关键过渡过程中坡面和渠道对岩石隆起速率增加的响应。已发表的数据和初步的地形分析结合河流沉积物中宇宙成因10Be的测量表明：(1)侵蚀速率在0.1~=1公里/Ma范围内有系统地变化；(2)碎屑宇宙成因10Be是该景观中有效的侵蚀速率监测工具。在圣加布里埃尔山脉岩性和气候条件相对一致(已知地形降雨模式)的情况下，侵蚀速率自西向东的系统性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。将测试对进一步定量理解构造和地形之间的关系至关重要的六个具体的可测试假设，并确定一套具体的现场和方法，这些假设应该产生这些假设的最终测试以及基本过程的量化。这项工作的更广泛影响跨越了用于促进扩大研究范围的五个一般NSF标准。从根本上说，该项目符合我们的主要教育目标：将实地研究纳入对不同受众的教育，加深他们对地球表面过程的了解，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.