کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6428921 1634751 2014 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Astronomical calibration of the Danian stage (Early Paleocene) revisited: Settling chronologies of sedimentary records across the Atlantic and Pacific Oceans
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
پیش نمایش صفحه اول مقاله
Astronomical calibration of the Danian stage (Early Paleocene) revisited: Settling chronologies of sedimentary records across the Atlantic and Pacific Oceans
چکیده انگلیسی


• The Zumaia and ODP Legs 198 and 208 records are tuned at the short-eccentricity level.
• The Danian stage consists of 11 consecutive ∼405-kyr long eccentricity cycles.
• The La2011 astronomical solution produces the best match to the geological record.
• Zumaia is proposed as Danian unit stratotype that has a duration of 4.415 My ±80 ky.
• Atlantic and Pacific Ocean stable isotope chronologies synchronised.

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 δ13C 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 ∼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 Ma66.022±0.040 Ma and 61.607±0.040 Ma61.607±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.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth and Planetary Science Letters - Volume 405, 1 November 2014, Pages 119–131