Abstract Granitic weathering profiles display highly diverse morphologies, reflecting the complex relationships between climate and weathering rates. Some profiles exhibit abrupt transitions from fresh bedrock to highly weathered material over short ( 30 m granitic weathering profile from the cool, temperate, Lysina catchment in the NW Czech Republic, from which we calculated mass transfer, weathering indices, and mineral specific weathering rates. The Lysina profile exhibits limited weathering extending >30 m into fractured bedrock, dominated by albite weathering at a rate of 9.3 × 10−17 mol m2 s−1. To identify environmental and geological controls on weathering front morphology and chemical weathering rates, Lysina was compared to previously published granitic weathering profiles from around the world. Weathering front morphology and weathering rates were calculated for the additional sites from published data and were correlated to mean annual precipitation (MAP), mean annual temperature (MAT), and erosion rates, with MAP having the strongest relationship. Higher MAP likely promotes lower saturation indices in pore waters, allowing weathering reactions to occur further from equilibrium. Comparison of erosion rates amongst the granitic catchments revealed an inconsistent effect on chemical weathering rates, but high erosion rates may promote weathering by reducing the thickness of the regolith and exposing the bedrock to reactive fluids. Mean annual temperatures appear to only have significant impacts on weathering fronts in environments with high precipitation and high erosion rates. Fractured bedrock profiles (Lysina and Rio Icacos) have higher weathering intensities, than the other sites studied here. High connected porosity in fractured rocks enhances water movement allowing more efficient removal of weathering products, thus reducing thermodynamic saturation, increasing weathering rates, and producing sharper weathering gradients. These findings indicate that CO2 drawdown on geological timescales is also likely to be governed by precipitation rates, as well as temperature, and that much of the climate-significant weathering may occur within very narrow zones of the Earth's surface.

中文翻译：

---

对比气候下花岗岩风化锋面的控制

摘要 花岗岩风化剖面显示出高度多样化的形态，反映了气候与风化速率之间的复杂关系。一些剖面表现出从新鲜基岩到高度风化材料的突然转变（来自捷克共和国西北部凉爽、温带的 Lysina 集水区的 30 m 花岗岩风化剖面，我们从中计算了传质、风化指数和矿物特定风化率。 Lysina 剖面表现出有限的风化作用，延伸 > 30 m 进入裂隙基岩，以 9.3 × 10−17 mol m2 s−1 的钠长石风化为主。为了确定对风化锋形态和化学风化率的环境和地质控制，Lysina 是与之前发布的世界各地的花岗岩风化剖面相比。风化锋形态和风化率是根据已发表的数据为其他地点计算的，并与年平均降水量 (MAP)、年平均温度 (MAT) 和侵蚀率相关，其中 MAP 具有最强的关系。较高的 MAP 可能会促进孔隙水中较低的饱和指数，从而使风化反应远离平衡发生。花岗岩集水区侵蚀率的比较显示对化学风化率的影响不一致，但高侵蚀率可能会通过减少风化层的厚度和将基岩暴露于反应流体来促进风化。年平均温度似乎只对高降水和高侵蚀率环境中的风化锋产生重大影响。断裂的基岩剖面（Lysina 和 Rio Icacos）比这里研究的其他地点具有更高的风化强度。裂隙岩石中的高连通孔隙度增强了水的运动，从而可以更有效地去除风化产物，从而降低热力学饱和度，增加风化速率，并产生更陡峭的风化梯度。这些发现表明，地质时间尺度上的 CO2 下降也可能受降水率和温度的控制，而且许多对气候具有重要意义的风化作用可能发生在地球表面非常狭窄的区域内。增加风化率，并产生更陡峭的风化梯度。这些发现表明，地质时间尺度上的 CO2 下降也可能受降水率和温度的控制，而且许多对气候具有重要意义的风化作用可能发生在地球表面非常狭窄的区域内。增加风化率，并产生更陡峭的风化梯度。这些发现表明，地质时间尺度上的 CO2 下降也可能受降水率和温度的控制，而且许多对气候具有重要意义的风化作用可能发生在地球表面非常狭窄的区域内。