气候变化领域集成服务门户(CCPortal): Millennial-scale denudation rates of the Santa Lucia Mountains, California: Implications for landscape evolution in steep, high-relief, coastal mountain ranges

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DOI	10.1130/B31907.1
	Millennial-scale denudation rates of the Santa Lucia Mountains, California: Implications for landscape evolution in steep, high-relief, coastal mountain ranges
	Young H.H.; Hilley G.E.
发表日期	2018
ISSN	167606
起始页码	1809
结束页码	1824
卷号	130 期号:2021-11-12
英文摘要	We used a suite of topographic metrics and cosmogenic 10Be-derived catchmentaveraged denudation rates from 18 watersheds to evaluate patterns of millennial-scale erosion of the Santa Lucia Mountains and test the explanatory power of the power-law incision rule for this landscape. Catchmentaveraged denudation rates in the study area vary between ~0.07 and 0.4 mm/yr, with a single drainage yielding a rate > 0.45 mm/yr. Channel steepness ranges from ~90 to 390 m for these catchments. We used these observations to test two forms of the power-law incision rule, one incorporating multiple, lithologically dependent erodibilities, and one containing a single erodibility term. Statistical analyses indicated the power-law incision rule provides an improved fit relative to a model that does not relate erosion rate to channel steepness. However, tests comparing both model forms indicate no significant improvement in model fit when using unique erodibility and channel steepness terms for each lithology. Estimates of erodibility coefficients were ~10-6-10-5 m0.2/yr for all rock types evaluated. Where range asymmetry was most pronounced, watershed divides were identified as mobile by the χ landscape metric, yet we resolved no cross-divide change in erosion rate. Conversely, divides predicted by χ to be close to an equilibrium configuration showed markedly different erosion rates in adjoining basins. These conflicting data sets, considered in conjunction with geomorphic indicators of river capture, may suggest that divide migration occurs in abrupt, punctuated episodes, rather than by gradual migration of divides. Finally, erosion rates measured here are broadly consistent with late Pleistocene uplift rates recorded by geomorphic markers and are a factor of 2-6 lower than previously reported rates of exhumation gauged by apatite helium thermochronology. This suggests that there has been a secular slowing of erosion, and perhaps rock uplift rates, between the Pliocene and today. © 2018 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184992
作者单位	Department of Geological Sciences, Stanford University, Braun Hall, Building 320, 450 Serra Mall, Stanford, CA 94305, United States
推荐引用方式 GB/T 7714	Young H.H.,Hilley G.E.. Millennial-scale denudation rates of the Santa Lucia Mountains, California: Implications for landscape evolution in steep, high-relief, coastal mountain ranges[J],2018,130(2021-11-12).
APA	Young H.H.,&Hilley G.E..(2018).Millennial-scale denudation rates of the Santa Lucia Mountains, California: Implications for landscape evolution in steep, high-relief, coastal mountain ranges.Bulletin of the Geological Society of America,130(2021-11-12).
MLA	Young H.H.,et al."Millennial-scale denudation rates of the Santa Lucia Mountains, California: Implications for landscape evolution in steep, high-relief, coastal mountain ranges".Bulletin of the Geological Society of America 130.2021-11-12(2018).