Classification of large-scale subaqueous bedforms; a new look at an old problem
Classification of large-scale subaqueous bedforms; a new look at an old problem
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DOI：
10.2110/jsr.60.160
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发表时间：
1990
影响因子：
2
通讯作者：
G. Ashley
中科院分区：
文献类型：
--
作者：
G. Ashley
1987年在德克萨斯州奥斯汀召开的SEPM年中会议上召开了一个题为“大规模水流-横向底形分类”的专题讨论会，目的是研究在河流、潮间带和海洋环境中形成的大型水下水流-横向底形分类所涉及的问题，并建议修改命名法。与会者的共识是，尽管大规模的流动横向底形（不包括沙丘）的形态范围很广，他们都占据了类似的位置，在较低的流量制度序列之间的涟漪和上平面床。各种各样的形式反映了次级效应，如渠化、水位波动、不稳定和反向流动。底形似乎不属于具有自然边界的大小类别，而是形成一个连续体，间距从不到1米到超过1 000米。因此，研讨会小组建议它们应该只有一个名字，DUNE。沙丘是首选，因为它在历史上优先于其他使用的术语，如megaripple和沙波。“沙丘”一词应该用形状的主要描述词来修饰（即，二维或三维）和基于间距的大小（小（0.6-5米），中（5-10米），大（10-100米）或非常大（> 100米）和形容词水下，当区分它们与风成沙丘很重要时。专家组建议采用一种描述性的基于形态学的分类，并提供潜在的遗传学依据。沉积物粒度和底形叠加等二级描述子可以更全面地描述自然界中水下沙丘的多样性。
A Symposium entitled "Classification of Large-Scale Flow-Transverse Bedforms" was convened at the 1987 Mid-Year Meeting of SEPM in Austin, Texas with the purpose of examining the problems involved in classifying large subaqueous flow-transverse bedforms developed in fluvial, intertidal, and marine environments, and recommending changes in nomenclature. The consensus of the participants is that despite the wide spectrum of morphologies of large-scale flow-transverse bedforms (excluding antidunes), they all occupy a similar position in the lower-flow-regime sequence between ripples and upper plane bed. The wide variety of forms is a reflection of secondary effects such as channelization, fluctuating water levels, and unsteady and reversing flows. The bedforms appear not to fall into size classes with naturally occurring boundaries but rather form a continuum with spacing from just under 1 m to over 1,000 m. The symposium panel proposes, therefore, that they should have only one name, DUNE. Dune is preferred as it has historical precedence over other terms in use, such as megaripple and sand wave. The term "dune" should be modified by primary descriptors of shape (i.e., 2-D or 3-D) and size based on spacing (small (0.6-5 m), medium (5-10 m), large (10-100 m) or very large (> 100 m) and the adjective subaqueous when it is important to distinguish them from eolian dunes. The panel recommends a morphologically based classification that is descriptive, with an underlying genetic rationale. Second order descriptors such a sediment size and bedform superposition may be used to describe more thoroughly the variety of subaqueous dunes in nature.