نتایج جستجو برای: paleocene

تعداد نتایج: 1189  

Journal: :Botanical Gazette 1908

2017
Richard E. Zeebe Kate Littler James C. Zachos

Multimillion-year proxy records across the Paleocene and Eocene show prominent variations on orbital time scales. The cycles, which have been identified at various sites across the globe, preferentially concentrate spectral power at eccentricity and precessional frequencies. It is evident that these cycles are an expression of changes in global climate and carbon cycling paced by astronomical f...

2003
D. V. Kent B. S. Cramer L. Lanci D. Wang R. Van der Voo

We hypothesize that the rapid onset of the carbon isotope excursion (CIE) at the Paleocene/Eocene boundary (V55 Ma) may have resulted from the accretion of a significant amount of 12C-enriched carbon from the impact of a V10 km comet, an event that would also trigger greenhouse warming leading to the Paleocene/Eocene thermal maximum and, possibly, thermal dissociation of seafloor methane hydrat...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2011
Anjali Goswami Guntupalli V R Prasad Paul Upchurch Doug M Boyer Erik R Seiffert Omkar Verma Emmanuel Gheerbrant John J Flynn

India's Late Cretaceous fossil mammals include the only undisputed pre-Tertiary Gondwanan eutherians, such as Deccanolestes. Recent studies have suggested a relationship between Deccanolestes and African and European Paleocene adapisoriculids, which have been variably identified as stem euarchontans, stem primates, lipotyphlan insectivores, or afrosoricids. Support for a close relationship betw...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2016
Alexander Gehler Philip D Gingerich Andreas Pack

The Paleocene-Eocene Thermal Maximum (PETM) is a remarkable climatic and environmental event that occurred 56 Ma ago and has importance for understanding possible future climate change. The Paleocene-Eocene transition is marked by a rapid temperature rise contemporaneous with a large negative carbon isotope excursion (CIE). Both the temperature and the isotopic excursion are well-documented by ...

2000
P. PELÁEZ-CAMPOMANES N. LÓPEZ-MARTÍNEZ

A new species of multituberculate mammal, Hainina pyrenaica n. sp. is described from Fontllonga-3 (Tremp Basin, Southern Pyrenees, Spain), correlated to the later part of chron C29r just above the K/T boundary. This taxon represents the earliest European Tertiary mammal recovered so far, and is related to other Hainina species from the European Paleocene. A revision of the species of Hainina al...

2015
Yi-Ming Cui Bin Sun Hai-Feng Wang David Kay Ferguson Yu-Fei Wang Cheng-Sen Li Jian Yang Qing-Wen Ma Navnith K.P. Kumaran

Thuja, a genus of Cupressaceae comprising five extant species, presently occurs in both East Asia (3 species) and North America (2 species) and has a long fossil record from Paleocene to Pleistocene in the Northern Hemisphere. Two distinct hypotheses have been proposed to account for the origin and present distribution of this genus. Here we recognize and describe T. sutchuenensis Franch., a ne...

2007
GISLE FOSSE SAM SON

Cretaceous multituberculate mammals of Europe are poorly known, as a rule represented by isolated teeth. The only exception is the Late Cretaceous (Maastrichtian) monotypic genus Kogaionon Riidulescu & Samson, 1996 from Romania, represented by a single skull, without dentaries, assigned to Kogaionidae Rhdulescu & Samson, 1996, Another kogaionid genus is Hainina Vianey-Liaud, 1979, represented b...

Journal: :Science 2006
Carlos Jaramillo Milton J Rueda Germán Mora

Several mechanisms have been proposed to explain the high levels of plant diversity in the Neotropics today, but little is known about diversification patterns of Neotropical floras through geological time. Here, we present the longest time series compiled for palynological plant diversity of the Neotropics (15 stratigraphic sections, 1530 samples, 1411 morphospecies, and 287,736 occurrences) f...

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