Colorado River terraces in the canyonlands region of southeastern Utah can be dated and analyzed to address the controls of incision and nature of the Colorado Plateau’s largest channel-steepness anomaly, Cataract Canyon. Field correlations supported by luminescence and cosmogenic-nuclide ages on strath terraces along Meander Canyon, upstream of Cataract Canyon, reveal a complex record of unsteady incision over the past ~340 k.y. at an average rate of ~0.4 mm/yr. Both an upstream progression of rapid incision and a unique sigmoidal long-profile pattern of terraces indicate incision in response to episodic baselevel fall. Also, terraces converge downstream with the anomalously low-gradient modern channel above Cataract Canyon. We interpret these results as indicating that growth of the Cataract Canyon knickzone is due to an erosion-salt tectonics feedback since at least the Mid Pleistocene, which has imparted unsteady, and currently elevated, local baselevel. More broadly, the canyonlands region is marked by rapid and unsteady incision that is complicated by local geologic controls even while being absent of any regional or mantle-driven uplift.

中文翻译：

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峡谷地地区（美国犹他州）的更新世科罗拉多河阶地记录了盐构造对卡内特峡谷峡谷带的不稳定、短暂的切割和生长

可以对犹他州东南部峡谷地地区的科罗拉多河阶地进行年代测定和分析，以解决科罗拉多高原最大的河道陡度异常——卡内特峡谷的切割和性质的控制问题。由卡内特峡谷上游 Meander Canyon 沿线的地​​层阶地的发光和宇宙成因核素年龄支持的场相关性揭示了过去约 340 ky 中以约 0.4 毫米/年的平均速率发生不稳定切割的复杂记录。快速切口的上游进展和梯田独特的 S 形长轮廓图案都表明切口是对偶发性基准面下降的响应。此外，梯田在下游与大瀑布峡谷上方异常低梯度的现代河道汇合。我们将这些结果解释为表明白内障峡谷尼克带的增长是由于至少自更新世中期以来的侵蚀盐构造反馈，这导致了不稳定的、目前升高的当地基准面。更广泛地说，峡谷地区的特点是快速且不稳定的切割，即使在没有任何区域或地幔驱动的隆起的情况下，局部地质控制也使这种切割变得复杂。