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Eocene

 

 

Books about Eocene

Eocene Biodiversity - Unusual Occurrences and Rarely Sampled Habitats
Initially, this work was designed to document and study the diversification of modern mammalian groups and was quite successful and satisfying. However, as field and laboratory work continued, there began to develop a suspicion that not all of the Eocene story was being told. It became apparent that most fossil samples, especially those from the American West, were derived from similar preservational circumstances and similar depositional settings. A program was initiated to look for other potential sources of fossil samples, either from non-traditional lithologies or from geographic areas that were not typically sampled. As this program of research grew it began to demonstrate that different lithologies and different geographic areas told different stories from those that had been developed based on more typical faunal assemblages. This book is conceived as an introduction to non-traditional Eocene fossils samples, and as a place to document and discuss features of these fossil assemblages that are rare or that come from rarely represented habitats.
The Terrestrial Eocene-Oligocene Transition in North America
The transition from the Eocene to the Oligocene epoch, occurring approximately 47 to 30 million years ago, was the most dramatic episode of climatic and biotic change since the demise of the dinosaurs. The mild tropical climates of the Paleocene and early Eocene were replaced by modern climatic conditions and extremes, including glacial ice in Antarctica. The first part of this book summarizes the latest information in the dating and correlation of the strata of late middle Eocene through early Oligocene age in North America. The second part reviews almost all the important terrestrial reptiles and mammals found near the Eocene-Oligocene boundary, in the White River Chronofauna--from the turtles, snakes and lizards to the common rodents, carnivores, oreodonts and deer of the Badlands. This is the first comprehensive treatment of these topics in over sixty years, and will be invaluable to vertebrate paleontologists, geologists, mammalogists and evolutionary biologists.
Paleoceanographic variability of extreme climates in the early Paleogene
Chapter 1 explores the relationship between the magnitude of the ETM-1 carbon isotope excursion (CIE) and paleo water depth in order to provide greater constraints on the wide ranging approximations of CIE magnitude. An accurate estimate of this value is crucial for developing realistic models of climate change and carbon cycle dynamics during the ETM-1 event and recovery, a full understanding of which may provide valuable predictive insights about current and future climate changes. The results of this study prove conclusively that the effects of truncation due to differential carbonate dissolution in response to shifts of lysocline/CCD depth during the characteristic ocean acidification of ETM-1 control the magnitude of the ETM-1 CIE as recorded in sediments as a function of depth. The apparent CIE magnitude decreases with increasing depth and dissolution. New analyses at the shallower Site 1263 provide the lowest delta13C values ever recorded at a pelagic site during this event, -2.2‰. These results also indicate that the full magnitude of the carbon cycle perturbation is larger than previously predicted from deep sea proxy records, at least -3.5‰. The implementation of new advances in geochemical methods allowed this study to also identify the maximum possible value for the CIE using compound specific stable isotope analysis of n-alkanes from terrestrial leaf waxes that had been deposited at Site 1263. By tapping into the potential of non-carbonate, dissolution resistant tracers of the global carbon cycle we know the maximum possible value of the ETM-1 CIE is -5.0‰. Chapter 2 of this work focuses on the timing, and ultimately, causes and consequences of transient perturbations of the global carbon system through the construction of an orbitally-tuned, high resolution carbon isotope stratigraphy for the late Paleocene and early Eocene. The high resolution delta 13C record is based on analyses of bulk carbonate materials from ODP Site 1262 in the SE Atlantic, Walvis Ridge, which has the only stratigraphically continuous section spanning the entire upper Paleocene and lower Eocene, and thus has the potential to provide insight on driving forces that contributed to the triggering of ETM-1. The role of orbital forcing with respect to the initiation of ETM-1 and ETM-2 has previously been posited based on occurrence coincident with eccentricity maxima, but this relationship has not been concretely established from a causal perspective (Lourens et al., 2005). The complete nature of this core and high resolution sampling interval make it the most likely candidate to become the reference section for studying the ETM-1 event. High sedimentation rates and relatively undisturbed deposition allow for the construction of a highly accurate, and most importantly, astronomically calibrated age model for cores from Site 1262 (Westerhold et al., 2005; Westerhold et al., 2007; Westerhold et al., 2008). Band pass Gaussian filters of delta 13C, delta18O, and Fe intensity reveal evolution of eccentricity cycles over time. Increased high amplitude cycles in the orbital frequency corresponding to the period of long eccentricity (400 kyr) dominate the Paleocene, indicating a highly unstable general climate state with frequently changing fluxes between oxidized and reduced reservoirs of carbon. This condition terminates abruptly at ETM-1 when the 400 kyr eccentricity cycles are significantly reduced in amplitude. The component of climate change caused by variation in the eccentricity of earth's orbit is amplified during the early Paleogene, possibly by the alignment of perihelion and equinox (vernal and autumnal).

The Rise of Mammals: The Paleocene & Eocene Epochs
The Paleocene epoch was a time of recovery for mammals and birds, survivors of the Mesozoic era. As the Earth continued to change as the continents drifted further apart, it was a world of evolutionary experiments, as birds and mammals each found ways to fill the ecological gaps left vacant by the disappearance of the dinosaurs. "The Rise of Mammals" details the pattern of bird and mammal evolution prior to the Cenozoic era as well as the critical first 10-million-year span of the Cenozoic known as the Paleocene epoch, during which mammals and birds rapidly adapted to the new ecological conditions. By the end of the Paleocene epoch, the roots of most modern birds and mammal families had been set, forging a series of divergent and specialized paths that continue to radiate some 55 million years later.
Late Paleocene-Early Eocene Biotic and Climatic Events in the Marine and Terrestrial Records
The editors have produced a well-organized state of the art compendium, which will form the baseline for studies of this problem well into the next millennium.
Global Warming: Greenhouse gas, Greenhouse effect, Solar variation, Effects of global warming, Temperature record, Paleocene-Eocene Thermal Maximum, Global climate model, Ocean acidification
Global Warming - Greenhouse gas, Greenhouse effect, Solar variation, Effects of global warming, Temperature record, Paleocene?Eocene Thermal Maximum, Global climate model, Ocean acidification, Climate change and agriculture, Shutdown of thermohaline circulation, Shutdown of thermohaline circulation, Economics of global warming, Mitigation of global warming, Kyoto Protocol, Geoengineering, Adaptation to global warming, Low-carbon economy, Global warming controversy, Politics of global warming, Climate change denial, Global dimming, Global cooling, List of scientists opposing scientific assessment of global warming.
Eocene
 The Eocene epoch, lasting from 55.8 ± 0.2 to 33.9 ± 0.1 Ma (million years ago), is a major division of the geologic timescale and the second epoch of the Palaeogene period in the Cenozoic era. The Eocene spans the time from the end of the Paleocene epoch to the beginning of the Oligocene epoch. The start of the Eocene is marked by the emergence of the first modern mammals. The end is set at a major extinction event called Grande Coupure (the "Great Break" in continuity), which may be related to the impact of one or more large bolides in Siberia and in what is now Chesapeake Bay. As with other geologic periods, the strata that define the start and end of the epoch are well identified, though their exact dates are slightly uncertain. The name Eocene comes from the Greek (eos, dawn) and (kainos, new) and refers to the "dawn" of modern ('new') mammalian fauna that appeared during the epoch.