Strong slope‐aspect control of regolith thickness by bedrock foliation
Strong slope‐aspect control of regolith thickness by bedrock foliation
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基岩叶理对风化层厚度的强坡向控制
DOI：
10.1002/esp.4947
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发表时间：
2020
影响因子：
3.3
通讯作者：
Russell P. Callahan
中科院分区：
文献类型：
--
作者：
J. D. Leone;W. S. Holbrook;C. Riebe;J. Chorover;Ty P.A. Ferré;B. Carr;Russell P. Callahan
地壳的多孔近地表层（关键区域）构成了生态系统的重要水库，为溪流提供基流，引导深层含水层补给，过滤地下水中的污染物，并调节地貌的长期演变。最近的研究表明，对风化层厚度的控制包括气候、构造、岩性和植被。然而，在景观尺度上对风化层结构和特性的观测相对较少，这意味着关键区域结构的理论模型没有得到完整的测试。在这里，我们提出了地震折射和电阻率调查，彻底描述了美国亚利桑那州圣卡塔利娜山脉一个小流域的地下结构特征，根据植被的差异，预计该流域的坡向对风化层结构的影响。我们的结果显示，相对斜坡上的物理特性和推断的风化层厚度存在鲜明对比，但与环境模型和观察到的植被模式的预期相反。尽管北坡的植被（以归一化植被指数 [NDVI] 表示）较密集，但南坡的风化层厚四倍（如较低的地震速度和电阻率所示）。这种对比无法用地形应力或传统山坡形态模型的变化来解释。相反，风化层厚度似乎是由变质叶理控制的：当叶理深入地形时，风化层较厚，而当叶理几乎平行于表面时，风化层较薄。我们假设，在该流域中，水力传导率和渗透能力控制风化：当叶理与地表地形平行时，渗透受到阻碍，风化层较薄，而当叶理与地形以较大角度相交时，水渗透更深，风化层较厚。这些结果表明，基岩叶理，或许还有沉积层理，可以控制风化层厚度，并且必须在关键区域发育模型中予以考虑。 © 2020 约翰威利父子公司。
The porous near‐surface layer of the Earth's crust – the critical zone – constitutes a vital reservoir of water for ecosystems, provides baseflow to streams, guides recharge to deep aquifers, filters contaminants from groundwater, and regulates the long‐term evolution of landscapes. Recent work suggests that the controls on regolith thickness include climate, tectonics, lithology, and vegetation. However, the relative paucity of observations of regolith structure and properties at landscape scales means that theoretical models of critical zone structure are incompletely tested. Here we present seismic refraction and electrical resistivity surveys that thoroughly characterize subsurface structure in a small catchment in the Santa Catalina Mountains, Arizona, USA, where slope‐aspect effects on regolith structure are expected based on differences in vegetation. Our results show a stark contrast in physical properties and inferred regolith thickness on opposing slopes, but in the opposite sense of that expected from environmental models and observed vegetation patterns. Although vegetation (as expressed by normalized difference vegetation index [NDVI]) is denser on the north‐facing slope, regolith on the south‐facing slope is four times thicker (as indicated by lower seismic velocities and resistivities). This contrast cannot be explained by variations in topographic stress or conventional hillslope morphology models. Instead, regolith thickness appears to be controlled by metamorphic foliation: regolith is thicker where foliation dips into the topography, and thinner where foliation is nearly parallel to the surface. We hypothesize that, in this catchment, hydraulic conductivity and infiltration capacity control weathering: infiltration is hindered and regolith is thin where foliation is parallel to the surface topography, whereas water infiltrates deeper and regolith is thicker where foliation intersects topography at a substantial angle. These results suggest that bedrock foliation, and perhaps by extension sedimentary layering, can control regolith thickness and must be accounted for in models of critical zone development. © 2020 John Wiley & Sons, Ltd.
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DOI：
10.1073/pnas.1404763111
发表时间：
2014-04
期刊：
Proceedings of the National Academy of Sciences
影响因子：
--
作者：
D. Rempe;W. Dietrich
通讯作者：
D. Rempe;W. Dietrich
探索方位的影响，以了解气候驱动的页岩风化变化的未来地球预报
DOI：
10.1029/2017jf004556
发表时间：
2019
期刊：
Journal of Geophysical Research: Earth Surface
影响因子：
--
作者：
Sullivan, P. L.;Goddéris, Y.;Shi, Y.;Gu, X.;Schott, J.;Hasenmueller, E. A.;Kaye, J.;Duffy, C.;Jin, L.;Brantley, S. L.
通讯作者：
Brantley, S. L.
影响因子：
5.3
作者：
N. West;E. Kirby;A. Nyblade;S. Brantley
通讯作者：
N. West;E. Kirby;A. Nyblade;S. Brantley
预测未来的关键区域
DOI：
10.12952/journal.elementa.000019
发表时间：
2013
期刊：
Elementa: Science of the Anthropocene
影响因子：
--
作者：
Goddéris, Yves;Brantley, Susan L
通讯作者：
Brantley, Susan L
山坡基岩风化和侧流协同演化的低维模型：2. 对风化和渗透性剖面、排水水力学和溶质输出路径的控制
影响因子：
3.2
作者：
Harman, Ciaran J.;Cosans, Cassandra L.
通讯作者：
Cosans, Cassandra L.