This report summarizes the international divisions and ages in the Geologic Time Scale, published in 2012 (GTS2012). Since 2004, when GTS2004 was detailed, major developments have taken place that directly bear and have considerable impact on the intricate science of geologic time scaling. Precam brian now has a detailed proposal for chronostratigraphic subdivision instead of an outdated and ab...

The fossil record indicates that crinoids have exhibited remarkable regenerative abilities since their origin in the Ordovician, abilities that they likely inherited from stem-group echinoderms. Regeneration in extant and fossil crinoids is recognized by abrupt differences in the size of abutting plates, aberrant branching patterns, and discontinuities in carbon isotopes. While recovery is comm...

—Four vascular plant lineages, the ferns, sphenopsids, progymnosperms, and seed plants, evolved laminated leaves in the Paleozoic. A principal coordinate analysis of 641 leaf species from North American and European floras ranging in age from Middle Devonian through the end of the Permian shows that the clades followed parallel trajectories of evolution: each clade exhibits rapid radiation of l...

Analyses of bulk petrographic data indicate that during the Late Paleozoic wildfires were more prevalent than at present. We propose that the development of fire systems through this interval was controlled predominantly by the elevated atmospheric oxygen concentration (p(O2)) that mass balance models predict prevailed. At higher levels of p(O2), increased fire activity would have rendered vege...

Basement rocks in the 17,000-square-mile region of southern Oklahoma crop out in the Wichita and Arbuckle Mountains and have been studied in subsurface samples from 175 wells. The rocks are divided into two contrasting provinces, each completely different from the other in age and petrologic character. Each province has played a different role in guiding the stratigraphic and structural evoluti...

Argillaceous minerals in deposits of various sedimentary formations are characterized by specific chemical-mineralogical and morphological genetic features changing different stages sedimentogenesis, diagenesis, catagenesis, metagenesis. their associations terrigenous, terrigenous carbonate, volcanic, halogenic characterized. Detail characterization is given for argillaceous early sedimentogene...