Download or read book Constraining the Paleobiological Response of Benthic Foraminifera to the Paleocene Eocene Thermal Maximum in an Active Margin Record written by Gabriel J. Valov (Graduate student) and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Paleoecology of Planktonic and Benthic Foraminifera During the Paleocene eocene Thermal Maximum PETM at San Agustin Cuba written by Christina R. Spielbauer and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 55 million years ago (ma) the Earth experienced an abrupt 4-8°C global temperature increase known as the Paleocene Eocene Thermal Maximum (PETM). The preservation of the PETM interval within the rock record is limited and one of the best examples within the Caribbean region is the San Agustin section in northwestern Cuba. Previous work on the San Agustin section included studies of the calcareous nannofossils as well as the planktonic foraminifera, this research expands on the original work to include benthic foraminifera. In the San Agustin section planktonic foraminiferal biostratigraphy shows a range from P4c due to the occurrence of Globanomalina pseudomenardii in the earliest samples and into E2 due to the occurrence of Globorotaloides quadrocameratus in the latest sample. This extends the planktonic foraminiferal biostratigraphy earlier than previously thought. Utilizing the identified species at the San Agustin section and Planktonic/Benthic (P/B) ratio data collected an understanding of aspects of the paleoenvironment were deduced. The San Agustin data shows a distinct increase in water depth at the site correlating with the Paleocene Eocene Thermal Maximum. Rock samples also occurred which contained very low to no foraminiferal return. In the western region of Cuba during the late Paleocene into the early Eocene the North American plate collided with the Greater Antillean Volcanic Arc. It is theorized that the low foraminiferal return is due to the active tectonics causing uplift and creating a lowstand, which lead to sediment shedding, and diluted the foraminifera within the sediments. This process of uplift and increased erosion appears to have occurred in the region multiple times before and after the PETM acting as the driving force of paleobathymetry. The exception to which is during the sea-level rise caused by the PETM warming which obscured the regional tectonics effect on the paleobathymetry.

Download or read book The Planktonic Foraminiferal Response to the Paleocene Eocene Thermal Maximum on the Atlantic Coastal Plain written by Caitlin Livsey and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cores on the Atlantic Coastal Plain contain an expanded record of the onset of the Paleocene Eocene Thermal Maximum (PETM), an abrupt global warming event occurring 55 mya. Though a seemingly well-studied event, details about what exactly occurred during the PETM are still lacking due to differential local effects, absence of precise time resolution, and considerable dissolution of deep sea carbonates at the onset of the event. Here we present high-resolution planktonic foraminiferal assemblage data from cores from Maryland and New Jersey that show significant changes in surface ocean habitats immediately before and during the onset of the event. Assemblages immediately below the PETM show evidence for environmental stress including oligotrophy, while marked changes in assemblages at the onset of the event reflect an increase in stratification. An anomalously high abundance of the stress indicating triserial/biserial planktonic foraminifera in the late Paleocene support the increase in environmental stress directly prior to the event on the coastal plain. We observe Acarinina sibaiyaensis, a species previously thought to have originated during the PETM, below the event at both sites. The appearance of A. sibaiyaensis prior to the PETM in the Atlantic Coastal Plain suggests that it evolved on the shelf in response to oligotrophy and tracked these conditions to the open ocean during the event. Planktonic foraminifera diversified on the shelf during the PETM likely due to a combination of sea level rise, warming of the coastal waters, and consequent increased stratification, which provided new habitats. We present the occurrence of variant morphologies of several planktonic foraminifera near the peak of the carbon isotope excursion at Bass River, which may signal the response of the assemblage to environmental perturbation. These high-resolution records of planktonic foraminifera from before and during the onset of the PETM offer insights into how the local environment shifted across the event, and what that meant for the evolution of Acarinina sibaiyaensis.

Download or read book The Paleocene Eocene Thermal Maximum Marine Response written by Tina M. J. Nielsen and published by . This book was released on 2008 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fluvial Response to the Paleocene Eocene Thermal Maximum in Western North America written by Brady Z. Foreman and published by . This book was released on 2013 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Paleocene-Eocene boundary ca. 56 million years ago is characterized by an extreme global warming event, known as the Paleocene-Eocene Thermal Maximum (PETM). The event is linked to the massive exogenic release of isotopically-light carbon into Earth's oceans and atmosphere, and is recognizable in the geologic record by an abrupt negative carbon isotope excursion in both organic and inorganic proxy records for duration of approximately 200,000 years. Previous studies indicate the PETM instigated massive changes in ocean and atmospheric circulation, which perturbed both terrestrial and marine environmental conditions and biotic systems. This study exploits the PETM to examine the effects of abrupt climate change on fluvial stratigraphy. The negative carbon isotope excursion associated with the PETM allows the timing and duration of the climate change to be identified independent of lithostratigraphic markers. Local climate shifts are constrained using circulation models, soil geochemistry, and paleobotanical records. Two areas are studied in detail, the Piceance Creek Basin of Colorado and the northern Bighorn Basin of Wyoming. In both areas anomalously thick and laterally persistent fluvial sand-bodies correlate with the PETM interval. In the Piceance Creek Basin the shift in fluvial deposition directly correlates with the onset of the PETM and persists beyond the carbon isotope excursion, whereas in the northern Bighorn Basin the shift appears to lag the isotope excursion by 10-20 thousand years and ends prior to the return to background climatic conditions. In the Piceance Creek Basin the change in sand-body geometry is associated with a shift to deeper paleoflow depths, wider channels, greater preservation of upper flow regime structures, prevalent crevasse splay deposits, and poorer drained floodplain soils. In contrast, within the Bighorn Basin there are no such changes and, apart from greater amalgamation, fluvial deposition appears to be largely unaffected by the PETM. When combined with other PETM terrestrial localities, the records demonstrate the PETM had substantial, but spatially diverse effects on basin-scale grain-size partitioning, discharge regimes, and river-floodplain dynamics. Aspects of the responses in the various basins are reminiscent of those predicted by two-dimensional basin-fill models, however, key differences highlight the role non-linearities, feedback loops, relaxation times, basin geometry, seasonality of precipitation, and vegetation factors play in determining large-scale depositional patterns. Consequently, it is concluded that short-term climatic events such as the PETM hold the potential to strongly alter basin sedimentation patterns, but that the sedimentologic-recorded climatic signal cannot be used to directly reconstruct paleoclimatic conditions. Instead a more appropriate approach is advocated that uses fluvial stratigraphy in concert with geochemical and other proxies to iteratively produce a more robust image of paleolandscape dynamics.

Download or read book The Impact of the Paleocene Eocene Thermal Maximum on Benthic Foraminiferal Shelf Communities written by Peter Stassen and published by . This book was released on 2012 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Paleocene Eocene Thermal Maximum in the Southern Indian Ocean written by Laura Jean Mitchell and published by . This book was released on 2007 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Planktonic Foraminifera Shell Response to the Paleocene Eocene Thermal Maximum written by Timothy Logan Lindemann and published by . This book was released on 2013 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Deep time Perspectives on Climate Change written by Mark Williams and published by Geological Society of London. This book was released on 2007 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cenozoic Record of Elongate Cylindrical Deep sea Benthic Foraminifera in the Southern and North Pacific Oceans and the Impact of the Early Eocene Global Warming Events written by Liesbeth Marie-Thérèse Karel Van Kerckhoven and published by . This book was released on 2014 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study was undertaken as a contribution to trying to determine the causes of the late Pliocene-middle Pleistocene extinction of a group of elongate deep-sea benthic foraminifera with specialised apertures (the “Extinction Group”, EG). The full Cenozoic evolutionary history of the EG was documented in the Southern and North Pacific Oceans in an attempt to identify palaeoenvironmental drivers of evolution of this group. A second objective was to assess whether the EG species were impacted by the late Palaeoecene-early Eocene warm events, like the ~30 % of deep-sea benthic foraminifera that became extinct during the Palaeocene/Eocene thermal maximum (PETM). The EG consists of the families Chrysalogoniidae, Glandulonodosariidae, Stilostomellidae, Ellipsoidinidae, Pleurostomellidae, Plectofrondiculariidae and several species from the Family of Nodosariidae. In this study, I recorded 102 species of the EG, including 15 taxa that had not been recognised previously. Five of these have now been formerly described as new species – Anastomosa boomgaarti Hayward and Van Kerckhoven, 2012; Anastomosa loeblichi Hayward and Van Kerckhoven, 2012; Siphonodosaria robertsoni Hayward and Van Kerckhoven, 2012; Ellipsoidella tappanae Hayward and Van Kerckhoven, 2012; Nodosarella kohli Hayward and Van Kerckhoven, 2012. Census counts on 98 EG species in 211 faunal samples (>63 mm) between the early Palaeocene (~65.5 Ma) and middle Eocene (~40 Ma) in Southern Ocean ODP Sites 689 and 690, and North Pacific Ocean ODP Site 865 indicated that there were no extinctions of these taxa during the PETM, and only three EG species had their global lowest occurrences within 0.5 myr of the PETM. However, this extreme warm event did impact on EG faunal composition on a global scale, with Strictocostella spp. becoming less dominant to the advantage of pleurostomellids and several other EG taxa. In terms of abundances and species richness, the EG was not or only slightly impacted by the PETM, and impacts differed between regions. The increase in species richness at the start of the PETM in the Southern Ocean possibly reflects a survival mechanism of the EG to the changing environmental conditions. Census counts on 92 EG species in 160 faunal samples between the late Cretaceous (~67.9 Ma) and Pleistocene (~0.5 Ma) in Southern Ocean ODP Site 689 and North Pacific Ocean ODP Site 1211 confirmed the EG thrived during the middle Eoceneearly Oligocene and went through periods of enhanced turnover and faunal composition changes during the rapid Eocene/Oligocene cooling event and the middlelate Miocene coolings. The Oligocene announced the start of the “Tweenhouse World” during which relative abundances of the EG in the benthic foraminiferal fauna started to decrease. However, EG diversity remained high during the Oligocene worldwide, possibly as a survival mechanism to compete with the benthic foraminiferal species with new ecological strategies (phytodetritus-feeding). Miocene decreases in EG relative abundances were mostly marked at the abyssal location, where EG faunal composition also went through major changes at ~10 Ma. Both locations, at opposite sides of the world, had 52 EG species in common, including most of the most common species. Average EG species duration was ~25 myrs in the Southern Ocean, and ~27 myrs in the North Pacific Ocean, concurring with findings of previous Cenozoic studies on the EG. From these studies, I conclude that the EG was affected by both warming and cooling extreme events in the deep-sea, possibly indirectly via their food source, to which they were highly adapted with specialised apertural modifications. The repeated preferred targeting of the usually highly successful stilostomellids, suggests species from this family were most specialised and also more vulnerable to extreme changes in environmental conditions. The decline in EG abundance and diversity during the “Tweenhouse” and “Icehouse World” oceans and their eventual extinction during the Mid-Pleistocene Transition were likely related to progressive and episodic global cooling impacting on the food source of this specialised group of deep-sea benthic foraminifera.

Download or read book Deconvolving Climate and Biotic Signals from Taphonomic Overprints in Deep sea Records of the Paleocene eocene Thermal Maximum written by Brittany Nicole Hupp and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Paleocene-Eocene Thermal Maximum (PETM), an ancient global warming event that occurred ~56 Ma, was closely associated with a rapid perturbation to the global carbon cycle, making the event an exceptionally-relevant analog for evaluating the future consequences of modern climate change. Here I examine deep-sea, planktic foraminifer records of the PETM from the Weddell Sea (ODP Site 690), southern Indian Ocean (ODP Site 1135), and equatorial Pacific Ocean (ODP Site 865). This dissertation seeks to (1) better characterize geochemical and biotic changes at various latitudes in response to PETM conditions through application of novel techniques, and (2) use the stratigraphic record of the PETM to assess how taphonomic processes such as sediment mixing and diagenesis have distorted deep-sea records of abrupt climate change. In chapters 1 and 2, I use stable carbon (Îþ13C) and oxygen (Îþ18O) isotope records constructed with graduated series of size-segregated planktic foraminifer shells to show how size-dependent sediment mixing has distorted the stratigraphic structure of the Site 690 PETM reference section. Chapter 3 demonstrates how the stable isotope signatures of individual foraminifer shells can be used to deconvolve the deleterious effects of sediment mixing on microfossil assemblages associated with abrupt biogeochemical perturbations. Application of this "isotopic filtering" method on the Site 865 PETM record reveals a transient but significant decrease in the diversity of tropical planktic foraminifer communities at the onset of the event, contrary to previous interpretations. Application of the aforementioned isotopic filtering method to high-latitude planktic foraminiferal assemblages of the PETM record of Site 1135 in chapter 4 revealed a similar, short-lived decrease in diversity, previously undetectable in the unfiltered assemblages. Lastly, in chapter 5, I generate parallel Îþ13C records of the carbon isotope excursion (CIE) marking the PETM in the Site 1135 section using traditional gas source mass spectrometry (GSMS) requiring analysis of whole foraminifer shells and secondary ion mass spectrometry (SIMS) where in-situ Îþ13C measurements are made on micrometer-scale domains within individual foraminifer shells. Comparison of these parallel Îþ13C records shows how GSMS analyses fail to capture the full magnitude of the CIE due to incorporated measurement of diagenetic calcite.

Download or read book Applications of Non Pollen Palynomorphs written by F. Marret and published by Geological Society of London. This book was released on 2021-10-29 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-awaited book about non-pollen palynomorphs (NPPs) aims to cover gaps in our knowledge of these abundant but understudied palynological remains. NPPs, such as fungal spores, testate amoebae, dinoflagellate cysts, acritarchs and animal remains, are routinely recovered from palynological preparations of marine or terrestrial material, from Proterozoic to recent geological times. This book gives the reader a comprehensive overview of the different types of NPPs, with examples from diverse time periods and environments. It provides guidance on sample preparation to maximize the recovery of these NPPs, detailed information on their diversity and ecological affinity, clarification on the nomenclature and demonstrates their value as environmental indicators. This volume will become the reference guide for any student, academic or practitioner interested in everything else in their palynological preparations.

Download or read book The Environmental Impact of the Paleocene eocene Thermal Maximum on the Coastal Ocean written by Thomas G. Quattlebaum (Jr.) and published by . This book was released on 2004 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sea surface Temperature Estimation written by C. J. Van Vliet and published by . This book was released on 1967 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: An autocorrelation analysis of six temperature records from the North Pacific and North Atlantic up to 40 years in length showed the existence of an oscillatory function with period 1 year for all the stations studied, and of another oscillatory function with period 0.5 year for most of the stations. A regression model containing annual and semiannual oscillatory terms was found to provide a good statistical fit to the observed daily temperatures. No long-term trends were detected in the sequences of annual mean temperatures, but there were significant differences among these temperatures. (Author).

Download or read book Paleocene Eocene Bathyal and Abyssal Benthic Foraminifera from the Atlantic Ocean written by R. C. Tjalsma and published by . This book was released on 1983 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Foraminiferal Ecology and Paleoecology written by Jere H. Lipps and published by . This book was released on 1979 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Impact of the Paleocene eocene Thermal Maximum on Benthic Foramiferal Shelf Communities written by Peter Stassen and published by . This book was released on 2012 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: