Not a bathtub: A consideration of sea-level physics for archaeological models of human migration
Not a bathtub: A consideration of sea-level physics for archaeological models of human migration
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DOI：
10.1016/j.jas.2021.105507
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发表时间：
2021-11-11
影响因子：
2.8
通讯作者：
Tryon, Christian
中科院分区：
文献类型：
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作者：
Borreggine, Marisa;Powell, Evelyn;Tryon, Christian
准确重建过去的海平面是模拟包括早期智人在内的古人类潜在迁徙路径的关键。古人类迁徙事件的模型通常使用“浴缸”模型来构建对古环境的估计，在“浴缸”模型中，假设海平面随着时间的推移根据“海平面”(全球平均)值而上升和下降。然而，过去冰盖的大小和形状存在很大的不确定性，特别是在最后一次冰川最大(LGM)之前，类似于26,000年前。此外，由于冰川均衡调整(GIA)的影响，区域海平面变化很大。这一过程包括地球在冰河时期对表面(冰和海洋)负荷变化的重力、形变和旋转反应。在这里，我们提供了GIA引起的海平面变化的最新物理描述，并考虑了这些影响以及新出版的冰盖历史对上一次冰川周期海平面变化的影响。作为例证，我们强调了这些问题对于研究古人类从Sunda迁移到Sahul的重要性，以及对于多佛海峡最后一次末次大冰川洪灾的时间安排。这些例子证明了将最新的冰盖历史和精确的海平面物理纳入考古研究的重要性。
Accurately reconstructing past sea level is key to simulating potential migration pathways of ancient hominins, including early Homo sapiens. Models of ancient human migration events commonly construct estimates of paleoenvironments using the "bathtub" model, in which sea level is assumed to rise and fall according to a "eustatic" (global average) value over time. However, large uncertainties exist on past ice sheet sizes and shapes, particularly prior to the Last Glacial Maximum (LGM), similar to 26,000 years ago. Moreover, regional sea level varies significantly due to the effects of glacial isostatic adjustment (GIA). That process includes Earth's gravitational, deformational, and rotational response to changing surface (ice plus ocean) loads across the ice age. Here, we offer an updated account of the physics of GIA-induced sea-level change and consider the impacts of these effects, together with a newly published ice sheet history, on sea-level changes across the last glacial cycle. As illustrations, we highlight the significance of these issues for studies of ancient human migration from Sunda to Sahul and for the timing of the final, post-LGM flooding of the Strait of Dover. These examples demonstrate the importance of incorporating updated ice sheet histories and accurate sea-level physics into archaeological research.