A global analysis of controls on submarine-canyon geomorphology
A global analysis of controls on submarine-canyon geomorphology
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DOI：
10.1016/j.earscirev.2022.104150
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发表时间：
2022-08
影响因子：
12.1
通讯作者：
Laura H. Bührig;L. Colombera;Marco Patacci;N. Mountney;W. McCaffrey
中科院分区：
文献类型：
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作者：
Laura H. Bührig;L. Colombera;Marco Patacci;N. Mountney;W. McCaffrey
利用从文献和开源世界水深测量中整理的282个全球分布的现代实例的数据库，研究了可能的控制因素在影响海底峡谷地貌中的作用。峡谷地貌通过峡谷的最大尺寸和平均尺寸、峡谷弯曲程度、平均峡谷海平面坡度和最大峡谷侧壁陡度来定量描述。评估了峡谷顶端相对于陆架断裂的位置、大陆边缘类型、陆源到汇系统环境、海洋环境和纬度的地貌特征如何变化。主要发现如下：(I)一些描述峡谷形态的尺度关系(例如，峡谷最大尺寸之间的比例关系，最大峡谷侧壁陡度与最大峡谷宽度和深度的关系)可以在全球范围内识别，表明它们的一般预测价值；(Ii)水动力过程(例如上升流、沿岸流和沿坡流)与峡谷形态之间可能存在的因果联系；(3)峡谷地貌方面的潜在预测因素包括峡谷是切入陆架还是局限于坡度、大陆边缘类型、海洋环境、纬度和陆架断裂深度；(4)所有环境中最大宽度与最大深度比分布的相似性表明，峡谷边缘侵蚀和峡谷内沉积的相对幅度不会因环境或峡谷大小而有很大差异。本研究中确定的峡谷地貌与环境变量之间的关系可以纳入描述峡谷地貌及其与深水系统其他要素的关系以及与更广泛的源汇背景的概念模型。这些结果为今后峡谷地貌的实验和数值研究提供了一个框架。
The role of possible controlling factors in influencing the geomorphology of submarine canyons has been investigated using a database of 282 globally distributed modern examples collated from the literature and open-source worldwide bathymetry. Canyon geomorphology has been characterised quantitatively in terms of maximum and average canyon dimensions, canyon sinuosity, average canyon thalweg gradient, and maximum canyon sidewall steepness. An assessment is made of how geomorphological characteristics vary with respect to the position of the canyon apex relative to the shelf break, continental-margin type, terrestrial source-to-sink system setting, oceanographic environment, and latitude. Scaling relationships between canyon morphometric parameters, and correlations between these and attributes of the canyon physiographic settings, terrestrial catchments, and continental shelves and slopes, have been quantified.Key findings are as follows: (i) a number of scaling relationships describing canyon morphometry (e.g. scaling between maximum canyon dimensions, relationships of maximum canyon sidewall steepness with maximum canyon width and depth) can be recognised globally, suggesting their general predictive value; (ii) possible causal links are identified between hydrodynamic processes (e.g. upwelling, longshore- and along-slope currents) and canyon morphology; (iii) potential predictors of aspects of canyon geomorphology include whether a canyon is incised into the shelf or confined to the slope, the continental-margin type, the oceanographic environment, latitude, and shelf-break depth; (iv) similarity in the distributions of maximum width-to-maximum depth ratios across all settings suggests that the relative magnitudes of canyon-margin erosion and intra-canyon deposition do not vary greatly depending on setting or canyon size.The relationships between canyon geomorphology and environmental variables identified in this study may be incorporated into conceptual models describing canyon geomorphology and its relationship both to other elements of deep-water systems, and to its broader source-to-sink context. The results provide a framework for future experimental and numerical studies of canyon geomorphology.