Revised geochronology, correlation, and dinosaur stratigraphic ranges of the Santonian-Maastrichtian (Late Cretaceous) formations of the Western Interior of North America
- Published
- Accepted
- Subject Areas
- Evolutionary Studies, Paleontology
- Keywords
- Biostratigraphy, Stratigraphy, Dinosaur, Cretaceous, 40Ar/39Ar, Radiometric dating
- Copyright
- © 2017 Fowler
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2017. Revised geochronology, correlation, and dinosaur stratigraphic ranges of the Santonian-Maastrichtian (Late Cretaceous) formations of the Western Interior of North America. PeerJ Preprints 5:e2554v2 https://doi.org/10.7287/peerj.preprints.2554v2
Abstract
Interbasinal stratigraphic correlation provides the foundation for all consequent continental-scale geological and paleontological analyses. Correlation requires synthesis of lithostratigraphic, biostratigraphic and geochronologic data, and must be periodically updated to accord with advances in dating techniques, changing standards for radiometric dates, new stratigraphic concepts, hypotheses, fossil specimens, and field data. Outdated or incorrect correlation exposes geological and paleontological analyses to potential error.
The current work presents a high-resolution stratigraphic chart for terrestrial Late Cretaceous units of North America, combining published chronostratigraphic, lithostratigraphic, and biostratigraphic data. 40Ar / 39Ar radiometric dates are newly recalibrated to both current standard and decay constant pairings. Revisions to the stratigraphic placement of most units are slight, but important changes are made to the proposed correlations of the Aguja and Javelina Formations, Texas, and recalibration corrections in particular affect the relative age positions of the Belly River Group, Alberta; Judith River Formation, Montana; Kaiparowits Formation, Utah; and Fruitland and Kirtland formations, New Mexico.
The stratigraphic ranges of selected clades of dinosaur species are plotted on the chronostratigraphic framework, with some clades comprising short-duration species that do not overlap stratigraphically with preceding or succeeding forms. This is the expected pattern that is produced by an anagenetic mode of evolution, suggesting that true branching (speciation) events were rare and may have geographic significance. The recent hypothesis of intracontinental latitudinal provinciality of dinosaurs is shown to be affected by previous stratigraphic miscorrelation. Rapid stepwise acquisition of display characters in many dinosaur clades, in particular chasmosaurine ceratopsids, suggests that they may be useful for high resolution biostratigraphy.
Author Comment
This is the latest version (May 2017) of the manuscript as submitted elsewhere. Most changes concern tone (removal of "I" etc), although significant additions are made to the section on the Judith River Formation terminology; further explanation of corrections to previous recalibrations; and additional explanation and discussion on how the hypothesis of latitudinal biogeographic provinciality was strongly affected by stratigraphic miscorrelation. The chart itself has some additions to the faunal list (as per recommendations made from comments on PeerJ preprints), and new taxa described since the first version of the chart was submitted in Winter 2016.
Supplemental Information
Stratigraphic Chart
Stratigraphic correlation of Upper Cretaceous terrestrial strata of the North American Western Interior from the Santonian through to the K-Pg boundary. Dinosaur taxon ranges plotted on to correlated geological units.
Recalibration Sheet
This sheet shows recalibration calculations for over 200 published Ar / Ar radiometric dates. These are recalibrated to the two current standards (Kuiper et al., 2008; Renne et al., 2011), shown on separate tabs. References are given within pop up notes for the respective recalibrated date(s).
References for Stratigraphic Chart
This text file lists all the references used in construction of the stratigraphic chart (Table S1).
