Studies of Cenozoic Deep-sea Benthonic Foraminifera in the Southern Ocean PDF Download

Author: Bruce Hayward Corliss
Publisher:
ISBN:
Category : Foraminifera, Fossil
Languages : en
Pages : 522

View

Book Description

Author: Liesbeth Marie-Thérèse Karel Van Kerckhoven
Publisher:
ISBN:
Category : Extinction (Biology)
Languages : en
Pages : 463

View

Book Description
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.

Author: C. Hillaire-Marcel
Publisher: Elsevier
ISBN: 0080525040
Category : Science
Languages : en
Pages : 863

View

Book Description
The present volume is the first in a series of two books dedicated to the paleoceanography of the Late Cenozoic ocean. The need for an updated synthesis on paleoceanographic science is urgent, owing to the huge and very diversified progress made in this domain during the last decade. In addition, no comprehensive monography still exists in this domain. This is quite incomprehensible in view of the contribution of paleoceanographic research to our present understanding of the dynamics of the climate-ocean system. The focus on the Late Cenozoic ocean responds to two constraints. Firstly, most quantitative methods, notably those based on micropaleontological approaches, cannot be used back in time beyond a few million years at most. Secondly, the last few million years, with their strong climate oscillations, show specific high frequency changes of the ocean with a relatively reduced influcence of tectonics. The first volume addresses quantitative methodologies to reconstruct the dynamics of the ocean andthe second, major aspects of the ocean system (thermohaline circulation, carbon cycle, productivity, sea level etc.) and will also present regional synthesis about the paleoceanography of major the oceanic basins. In both cases, the focus is the “open ocean leaving aside nearshore processes that depend too much onlocal conditions. In this first volume, we have gathered up-to-date methodologies for the measurement and quantitative interpretation of tracers and proxies in deep sea sediments that allow reconstruction of a few key past-properties of the ocean( temperature, salinity, sea-ice cover, seasonal gradients, pH, ventilation, oceanic currents, thermohaline circulation, and paleoproductivity). Chapters encompass physical methods (conventional grain-size studies, tomodensitometry, magnetic and mineralogical properties), most current biological proxies (planktic and benthic foraminifers, deep sea corals, diatoms, coccoliths, dinocysts and biomarkers) and key geochemical tracers (trace elements, stable isotopes, radiogenic isotopes, and U-series). Contributors to the book and members of the review panel are among the best scientists in their specialty. They represent major European and North American laboratories and thus provide a priori guarantees to the quality and updat of the entire book. Scientists and graduate students in paleoclimatology, paleoceanography, climate modeling, and undergraduate and graduate students in marine geology represent the target audience. This volume should be of interest for scientists involved in several international programs, such as those linked to the IPCC (IODP – Integrated Ocean Drilling Program; PAGES – Past Global Changes; IMAGES – Marine Global Changes; PMIP: Paleoclimate Intercomparison Project; several IGCP projects etc.), That is, all programs that require access to time series illustrating changes in the climate-ocean system. Presents updated techniques and methods in paleoceanography Reviews the state-of-the-art interpretation of proxies used for quantitative reconstruction of the climate-ocean system Acts as a supplement for undergraduate and graduate courses in paleoceanography and marine geology

Author:
Publisher:
ISBN:
Category : Marine biology
Languages : en
Pages : 764

View

Book Description

Author: Y. Takayanagi
Publisher:
ISBN:
Category : Benthos
Languages : en
Pages : 472

View

Book Description

Author: United States. National Oceanic and Atmospheric Administration
Publisher:
ISBN:
Category : Marine biology
Languages : en
Pages : 1200

View

Book Description

Author: Ann Holbourn
Publisher: John Wiley & Sons
ISBN: 1118452526
Category : Science
Languages : en
Pages : 1115

View

Book Description
An up-to-date atlas of an important fossil and living group, with the Natural History Museum. Deep-sea benthic foraminifera have played a central role in biostratigraphic, paleoecological, and paleoceanographical research for over a century. These single–celled marine protists are important because of their geographic ubiquity, distinction morphologies and rapid evolutionary rates, their abundance and diversity deep–sea sediments, and because of their utility as indicators of environmental conditions both at and below the sediment–water interface. In addition, stable isotopic data obtained from deep–sea benthic foraminiferal tests provide paleoceanographers with environmental information that is proving to be of major significance in studies of global climatic change. This work collects together, for the first time, new morphological descriptions, taxonomic placements, stratigraphic occurrence data, geographical distribution summaries, and palaeoecological information, along with state-of-the-art colour photomicrographs (most taken in reflected light, just as you would see them using light microscopy), of 300 common deep-sea benthic foraminifera species spanning the interval from Jurassic - Recent. This volume is intended as a reference and research resource for post-graduate students in micropalaeontology, geological professionals (stratigraphers, paleontologists, paleoecologists, palaeoceanographers), taxonomists, and evolutionary (paleo)biologists.

Author:
Publisher:
ISBN:
Category : Antarctica
Languages : en
Pages : 328

View

Book Description

Author: James P. Kennett
Publisher: Geological Society of America
ISBN: 0813711630
Category : Science
Languages : en
Pages : 518

View

Book Description

Author: Frank P. C. M. Van Morkhoven
Publisher:
ISBN:
Category : Benthos
Languages : en
Pages : 440

View

Book Description