资源环境科技发展态势分析平台

Spatial analysis of discrepancies in sea‐level estimates derived from “backstripping” Mid‐Atlantic margin cores reveals a coherent signal that can be fit with a 10^3‐km wavelength, 45‐m amplitude sinusoid that moved across the margin at a rate and direction of motion generally opposite to that of the North American Plate. This signal we observe suggests topographical uplift occurred over much of the Mid‐Atlantic region since 35 Ma and may be superimposed upon a longer‐wavelength signal of Cenozoic subsidence associated with the subducted Farallon plate passing beneath the Mid‐Atlantic margin. Our statistical modeling of Mid‐Atlantic margin strata suggests that: 1) Cenozoic subsidence is likely to have occurred, but is very unlikely to have exceeded 100 m in magnitude; and 2) variations in ocean basin volume are likely to have contributed to 39 ± 24 m (1σ) of global‐mean geocentric sea‐level fall over the past 55 million years.

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