CRET1 CHRONOSTRATIGRAPHIC DATABASE

INTRODUCTION

The CRET1 Chronostratigraphic Database is a compilation of more than 3400 fossil taxa and marker beds from numerous published worldwide sections that span from the Jurassic/Cretaceous boundary to the Cretaceous/Paleogene boundary (Table 1). The numerical ages of the ranges have been interpolated by graphic correlation of the sections listed in (Table 2). The ranges of first and last occurrences (FO/LO) are presented in mega-annums calibrated to Global Stratotype and Section Points or to standard reference sections where GSSPs are not yet accepted (Table 3). The ages of the taxa and marker beds are preliminary for two reasons: 1) conversion from the 1990 time scale in which the age of the Cenomanian/Turonian boundary was 90.5 Ma to the 1993/2004 age of 93.3-93.5 Ma is not yet complete so that the FO of some taxa limited to the Cenomanian are calibrated to the old time; 2) ranges of some taxa are constrained by very few sections so that their ranges may extend as new sections are added.

This database may be used as a look-up table or as a point of reference for various quantitative methods of interpolation and calibration of other stratigraphic sections. Please note errors and discrepancies in an email to: rwscott@ix.netcom.com Comments are welcome.

Table 1. Preliminary File: Cretaceous 1 DATABASE; First/ Last Occurrences (FO/LO) of some Cenomanian/Turonian taxa not yet re-calibrated from 1990 age of Cen/Tur boundary at 90.5 Ma to revised age at 93.00 Ma (within the error bar of 93.3±0.2 Ma (Obradovich, 1993, Geol. Assoc. Canada, Spec. Paper 39:379-396) and 93.06±0.25 Ma (Kowallis et al., 1995, Cret. Res., p. 127).

Table 2. Section Catalog Files for Cretaceous Chronostratigraphic Database.

Table 3. Cretaceous stage type localities, criteria, and GSSPs in CRET1 Chronostratigraphic Database.