Yuan Xiaoping, Li Yuqiang, Brune Sascha, Li Kai, Pons Michaël, Wolf Sebastian G
State Key Laboratory of Biogeology and Environmental Geology, Hubei Key Laboratory of Critical Zone Evolution, School of Earth Sciences, China University of Geosciences, Wuhan, China.
Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences, Potsdam, Germany.
Nat Commun. 2024 Nov 28;15(1):10362. doi: 10.1038/s41467-024-54690-4.
Crustal thickening associated with orogenic growth elevates topography, causing orographic enhancement of precipitation, which in turn facilitates local erosion and possibly intensifies localization of deformation. How these three processes-deformation, precipitation, and erosion-coordinate during orogenic growth remains unknown. Here, we present a numerical model where tectonics, surface processes, and orographic precipitation are tightly coupled, and explore the impact on low, intermediate, and high erodibility orogens. We show that, for intermediate erodibility models, rock uplift rates and precipitation rates correlate well with erosion rates during the formation of orogenic plateaus with high correlation coefficients of ~0.9 between rock uplift and erosion rates, and ~0.8 between precipitation and erosion rates. We demonstrate a cyclicity of correlation evolution among uplift, precipitation, and erosion rates through the development of new faults propagating outward. These results shed insights into the relative tectonic or climatic control on erosion in active orogens (e.g., Himalayas, Central Andes, and Southern Alps of New Zealand), and provide a plausible explanation for several conflicting data and interpretations in the Himalayas, which depend on the stage of maturity of the newest fault and the relative locations to old faults.
与造山带生长相关的地壳增厚使地形抬升，导致降水的地形增强，这反过来又促进了局部侵蚀，并可能加剧变形的局部化。在造山带生长过程中，变形、降水和侵蚀这三个过程如何协调仍不清楚。在这里，我们提出了一个数值模型，其中构造、地表过程和地形降水紧密耦合，并探讨了对低、中、高侵蚀性造山带的影响。我们表明，对于中等侵蚀性模型，在造山高原形成过程中，岩石隆升速率和降水速率与侵蚀速率具有良好的相关性，岩石隆升与侵蚀速率之间的相关系数约为0.9，降水与侵蚀速率之间的相关系数约为0.8。通过向外扩展的新断层的发育，我们展示了隆升、降水和侵蚀速率之间相关性演化的周期性。这些结果为活跃造山带（如喜马拉雅山脉、安第斯山脉中部和新西兰南阿尔卑斯山）侵蚀的相对构造或气候控制提供了见解，并为喜马拉雅山脉中几个相互矛盾的数据和解释提供了合理的解释，这取决于最新断层的成熟阶段以及与老断层的相对位置。
