Spatial and Temporal Variations of Incision Rate of the Middle Yellow River and Its Tributaries

Abstract

AbstractWe present a model to reconstruct spatiotemporal variation of uplift along the Jinshan Gorge of the Yellow River of Northern China based on quantitative analysis of the river channel profiles. We focus on the tributaries along the gorge that drain from the Loess Plateau on the Ordos crustal block. Base level fall on a tributary is genetically related to its trunk channel incision through the incision rate of the confluence point. We leverage this relationship to reconstruct a scaled incision history at each confluence point from an inversion analysis of tributary networks governed by the stream power law. In this way, we create an artificial geomorphic marker, that we refer to as a “pseudo‐terrace.” These metrics provide information on the incision history of the Yellow River. Our result shows a recent acceleration of river incision along the southern Jinshan Gorge, including spatial variations indicative of tectonic activity. The northern gorge exhibits more uniform and steady incision rates. This pattern can be attributed to on‐going lithospheric mantle upwelling beneath the southern Ordos Block.