They ask if this supposed evolution happened six and half or nearer seven million years ago, but the circular reasoning that underlies evolutionary ages suggests they should ask if the millions of years ever really occurred.
The youngest geomagnetic polarity reversal, the Matuyama-Brunhes boundary (MBB), provides an important datum plane for sediments, ice cores, and lavas.
We apply this method simultaneously to one Greenland (NGRIP) and three Antarctic (EPICA Dome C, EPICA Dronning Maud Land, and Vostok) ices cores, and refine existent chronologies.Our results show that consistent ice and gas chronologies can be derived for depth intervals that are well-constrained by relevant glaciological data.PY - 2015/4/24Y1 - 2015/4/24N2 - The youngest geomagnetic polarity reversal, the Matuyama-Brunhes boundary (MBB), provides an important datum plane for sediments, ice cores, and lavas.Its frequently cited age of 780 ka is based on orbital tuning of marine sedimentary records, and is supported by 40Ar/39Ar dating of Hawaiian lavas using recent age calibrations.This method enables us to gather widespread chronological information and to use regional or global markers (i.e., methane, volcanic sulfate, Beryllium-10, tephra layers, etc.) to link the core chronologies stratigraphically.
Confidence intervals of the new dating scenarios can be calculated thanks to the probabilistic formulation of the new method, which takes into account both modeling and data uncertainties.Here, we present a U-Pb zircon age of 772.7 ± 7.2 ka from a marinedeposited tephra just below the MBB in a forearc basin in Japan.U-Pb dating has a distinct advantage over Ar dating in that it is relatively free from assumptions regarding standardization and decay constants.The poles could have flipped much faster back then.Often, researchers will transfer age assignments from a published geologic chart to local field observations.Climate physicist Jake Hebert kicked the supports out from beneath the whole enterprise of orbital tuning by pointing out that scientists started to use a different age assignment than the original one used to establish the validity of orbital tuning. Beneath layers of tech talk, we find a dog chasing its tail.