Astronomical calibration of the Danian stage (Early Paleocene) revisited: Settling chronologies of sedimentary records across the Atlantic and Pacific Oceans
Astronomical calibration of the Danian stage (Early Paleocene) revisited: Settling chronologies of sedimentary records across the Atlantic and Pacific Oceans
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DOI：
10.1016/j.epsl.2014.08.027
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发表时间：
2014-11-01
影响因子：
5.3
通讯作者：
Kroon, Dick
中科院分区：
文献类型：
--
作者：
Dinares-Turell, Jaume;Westerhold, Thomas;Kroon, Dick
从天文学上调整沉积记录到精确的轨道解，在地质时间尺度上取得了前所未有的分辨率。然而，由于405-kyr偏心旋回的确切数量和关键记录之间的精确相关性的不确定性，古新世的一致天文时间尺度的构建存在争议。在这里，我们提出了一个新的大年综合地层格架，利用巴斯克盆地的陆地Zumaia和Sopelana半深海剖面和海洋钻探计划（ODP）第198条（北太平洋Shatsky隆起）和第208条（南大西洋Walvis Ridge）期间钻探的深海记录，解决了之前的差异。新的相干地层学利用了ODP岩心的合成图像、Zumaia新的全岩三角洲C-13同位素记录和Sopelana的新磁地层数据。我们在所有研究的大年系序列中一致观察到11 405-kyr的偏心旋回。我们在所有研究剖面之间的生物事件和稳定同位素事件在类似于100 kyr的短偏心水平上实现了强大的相关性，这是古气候解释的先决条件。通过与最新轨道解La2011的对比和后续调整，白垩纪-古近纪（K-Pg）和达尼安-塞兰迪（D-S）边界的天文校准年龄分别为66.022 +/- 0.040 Ma和61.607 +/- 0.040 Ma。低沉积速率在中大年期的所有记录中都很常见，包括在过去妨碍了旋回正确识别的海洋记录中明显的凝聚期。这里应用的综合盆地间方法揭示了时间尺度构建的陷阱，特别是滤波技术，并表明在构建轨道年表时必须谨慎和仔细。最后，祖玛亚剖面已经承载了Selandian全球边界层型剖面和点（GSSP），未来可以作为全球大年单元层型。(C) 2014 Elsevier B.V.版权所有
Astronomical tuning of sedimentary records to precise orbital solutions has led to unprecedented resolution in the geological time scale. However, the construction of a consistent astronomical time scale for the Paleocene is controversial due to uncertainties in the recognition of the exact number of 405-kyr eccentricity cycles and accurate correlation between key records. Here, we present a new Danian integrated stratigraphic framework using the land-based Zumaia and Sopelana hemipelagic sections from the Basque Basin and deep-sea records drilled during Ocean Drilling Program (ODP) Legs 198 (Shatsky Rise, North Pacific) and 208 (Walvis Ridge, South Atlantic) that solves previous discrepancies. The new coherent stratigraphy utilises composite images from ODP cores, a new whole-rock delta C-13 isotope record at Zumaia and new magnetostratigraphic data from Sopelana.We consistently observe 11 405-kyr eccentricity cycles in all studied Danian successions. We achieve a robust correlation of bioevents and stable isotope events between all studied sections at the similar to 100-kyr short-eccentricity level, a prerequisite for paleoclimatic interpretations. Comparison with and subsequent tuning of the records to the latest orbital solution La2011 provides astronomically calibrated ages of 66.022 +/- 0.040 Ma and 61.607 +/- 0.040 Ma for the Cretaceous-Paleogene (K-Pg) and Danian-Selandian (D-S) boundaries respectively. Low sedimentation rates appear common in all records in the mid-Danian interval, including conspicuous condensed intervals in the oceanic records that in the past have hampered the proper identification of cycles. The comprehensive interbasinal approach applied here reveals pitfalls in time scale construction, filtering techniques in particular, and indicates that some caution and scrutiny has to be applied when building orbital chronologies. Finally, the Zumaia section, already hosting the Selandian Global Boundary Stratotype Section and Point (GSSP), could serve as the global Danian unit stratotype in the future. (C) 2014 Elsevier B.V. All rights reserved.