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[1] A rock magnetic cyclostratigraphy, based on anhysteretic remanent magnetization (ARM) intensity variations, was developed for the Eocene Arguis Formation in the Spanish Pyrenees. The Arguis Formation was sampled for ARM cyclostratigraphy, rock magnetic, and paleomagnetic analyses. Rock magnetic measurements indicate that the dominant magnetic mineral controlling the ARM cyclostratigraphy is...

The Arctic Coring Expedition (ACEX) proved to be one of the most transformational missions in almost 40 year of scientific ocean drilling. ACEX recovered the first Cenozoic sedimentary sequence from the Arctic Ocean and extended earlier piston core records from ∼1.5 Ma back to ∼56 Ma. The results have had a major impact in paleoceanography even though the recovered sediments represents only 29%...

Geochemical and modeling studies suggest that the transition from the "greenhouse" state of the Late Eocene to the "icehouse" conditions of the Oligocene 34-33.5 Ma was triggered by a reduction of atmospheric pCO2 that enabled the rapid buildup of a permanent ice sheet on the Antarctic continent. Marine records show that the drop in pCO2 during this interval was accompanied by a significant dec...

The origins of South America's exceptional plant diversity are poorly known from the fossil record. We report on unbiased quantitative collections of fossil floras from Laguna del Hunco (LH) and Río Pichileufú (RP) in Patagonia, Argentina. These sites represent a frost-free humid biome in South American middle latitudes of the globally warm Eocene. At LH, from 4,303 identified specimens, we rec...

The Eocene-Oligocene Boundary (~34 million years ago) marks one of the largest extinctions of marine invertebrates in the world oceans and of mammalian fauna in Europe and Asia in the Cenozoic era. A shift to a cooler climate across this boundary has been suggested as the cause of this extinction in the marine environment, but there is no manifold evidence for a synchronous turnover of flora, f...

the eocene volcanic rocks from the southwest of the jandaq (kuh-e-godar-e-siah, central-east iran micro-continent) are andesitic basalt and andesite in composition. these rocks contain xenoliths with granulitic mineralogy. mineral assemblage of these xenoliths is plagioclase + phlogopite + corundum + sillimanite + chlorite + phengite with granublastic, poiklioblastic and foliated textures in th...

The early Eocene is a period of significant change in the composition of North American turtle faunas. Over the first 2.2 million years of the Eocene, the fossil record documents several immigrations into depositional basins of the Western Interior and an expansion in the ecological niches of turtles toward herbivory. Focusing on the Willwood Formation, we document change in generic and species...

Samples of bentonite layers from altered volcanic ash layers of the Anthering Formation in Salzburg, Austria, which most likely covers the Paleocene/Eocene boundary, were analyzed for their chemical composition. The results of the major and trace element determination confirm the previously suggested appearance from at least two different primary localities. One sample has low abundances in TiO...

Benthic foraminifera were studied as part of an investigation of the Fortuna Section (Betic Cordillera, Southeastern Spain), undertaken to document a candidate section for the Global Stratotype Section and Point (GSSP) for the base of the Lutetian Stage (Ypresian/Lutetian boundary). Benthic foraminiferal assemblages in this section are mostly dominated by calcareous taxa (~50-96%) and by infaun...