Publication Date:
2019-07-13
Description:
Ocean Drilling Program Leg 189 recovered a potentially complete shallow marine record of the Cretaceous-Paleogene boundary (KPB) at Site 1172 on the East Tasman Plateau. Here we present high-resolution (cm-scale) data from micropaleontology, geochemistry, sedimentology, and paleomagnetism that provide no evidence for a complete KPB, but instead suggest a boundary-spanning hiatus of at least 0.8 Ma. We interpret this hiatus to represent the sequence boundary between the uppermost Maastrichtian Tal.1 and lowermost Danian Ta1.2/ Da- 1 3rd-order sequence stratigraphic cycles. Microfloral assemblages indicate generally shallow paleodepths, restricted circulation, and eutrophic conditions through the section. Paleodepths progressively shallow through the late Maastrichtian, while more oceanic and warmer conditions dominate the early Danian. The Site 1172 KPB section is broadly comparable to other southern highlatitude sections in Antarctica and New Zealand, but appears to record a shallower and more restricted environment that permitted a eustatically-driven hiatus across the KPB mass extinction event.
Keywords:
Lunar and Planetary Science and Exploration
Type:
The Cenozoic Southern Ocean: Techtonics, Sedimentation and Climate Change Between Australia and Antarctica; 151; 93-112
Format:
text
Permalink
