Limestone-marl alternations: A warm-water phenomenon?
Limestone-marl alternations: A warm-water phenomenon?
复制标题
石灰岩-泥灰岩交替：温水现象？
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
A. Munnecke
中科院分区：
文献类型：
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作者：
H. Westphal;A. Munnecke
古代石灰岩-泥灰岩交替集中在类似于现代世界霰石堆积场所的环境中。它们通常出现在热带-亚热带气候带的陆架上，被动大陆边缘的数量远多于活跃大陆边缘，并且在上升流区很少见。在最近的研究中，文石被认为在大多数石灰岩-泥灰岩交替典型的差异成岩作用中发挥着重要作用。古代石灰岩-泥灰岩交替沉积环境与现代霰石堆积的巧合是这一假设的有力例证。如果得到证实，它可以为广泛的古环境解释提供一个有价值的工具。另一种不同类型的石灰岩-泥灰岩交替是由于白垩纪方解石浮游生物生产力的爆炸性结果：这些中上层浮游生物的成岩作用方式根本不同。
Ancient limestone-marl alternations are concentrated in settings analogous to loci of aragonite accumulation in the modern world. They typically occur on shelves in the tropical-subtropical climate belt, are far more abundant on passive continental margins than on active ones, and are rare in upwelling zones. In recent studies, aragonite was proposed to play an important role in differential diagenesis typical of most limestone-marl alternations. The coincidence of depositional settings of ancient limestone-marl alternations and modern aragonite accumulation is a strong case for this hypothesis. If confirmed, it could provide a valuable tool for broad-scale paleoenvironmental interpretations. An additional, different type of limestone-marl alternations resulted from the Cretaceous explosion in productivity of calcitic plankton: these pelagic ones are fundamentally different in their style of diagenesis.