scispace - formally typeset
Search or ask a question

Showing papers on "Foraminifera published in 2018"


Book
15 Aug 2018
TL;DR: In this paper, the Mesozoic larger benthic foraminifera assemblages in the understanding of the global distribution of carbonate sediments and their value in contributing raw data to palaeoenvironmental and palaeoclimatic models.
Abstract: 1. Biology and history of larger benthic foraminiferaHistory and biological classification of foraminiferaEcology of the living larger foraminiferaPalaeontological and evolutionary history of the larger foraminiferaTaxanomic features used in larger foraminiferal classificationBiostratigraphic distribution over time of larger foaminiferaGeneral factors effecting the evolution of marine species in the mid to late Phanerozic2. The Palaeozoic larger benthic foraminifera: The Carboniferous and PermianMorphology and taxonomy of Palaeozoic larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of the fusulinidsPalaeogeographic distribution of the fusulinids3. The Mesozoic larger benthic foraminifera: the TriassicMorphology and taxonomy of Triassic larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Triassic foraminiferaPalaeogeographic distribution of Triassic foraminifera4. The Mesozoic larger benthic foraminifera: the JurassicMorphology and taxonomy of Jurassic larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Jurassic foraminiferaPalaeogeographic distribution of Jurassic foraminifera5. The Mesozoic larger benthic foraminifera: the CretaceousMorphology and taxonomy of Cretaceous larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Cretaceous foraminiferaPalaeogeographic distribution of Cretaceous foraminifera6. The Palaeogene larger benthic foraminiferaMorphology and taxonomy of Palaeogene larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Palaeogene foraminiferaPalaeogeographic distribution of Palaeogene foraminifera7. The Neogene larger benthic foraminiferaMorphology and taxonomy Neogene larger benthic foraminiferaBiostratigraphy and phylogenetic evolutionPalaeoecology of Neogene foraminiferaPalaeogeographic distribution of Neogene foraminifera8. SynthesisImportance of application of larger foraminifera in biostratigraphyImportance of larger foraminifera as marine environmental indicatorsThe significance of the larger foraminifera assemblages in the understanding of the global distribution of carbonate sediments and their value in contributing raw data to palaeoenvironmental and palaeoclimatic modelsAppendixNomenclature terminology and glossary

299 citations



Journal ArticleDOI
TL;DR: Large-scale genome and transcriptomes analyses reveal the presence of a denitrification pathway in foraminifera species of the genus Globobulimina as well as a wide range of nitrite/nitrate transporters, including the enzymes nitrite reductase and nitric oxide reductases.

64 citations


Journal ArticleDOI
Willem Renema1
TL;DR: In this paper, the occurrences of individual species of the, in most environments, most abundant Central Indo-Pacific LBF, the Amphisteginidae, Calcarinidae and Nummulitidae are reviewed.

63 citations


Journal ArticleDOI
TL;DR: In this article, a new calibration data set based on 234 replicate analyses of 9 planktonic and 2 benthic species of foraminifera collected from recent core-top sediments, with calcification temperatures ranging from −2 to 25°C.

59 citations


Book
30 Apr 2018
TL;DR: BouDagher-Fadel et al. as mentioned in this paper presented a comprehensive reference work on the evolution and Geological significance of larger benthic foraminifera, including a palaeogeographic interpretation of the shallow marine late Paleozoic to Cenozoic world.
Abstract: Evolution and Geological Significance of Larger Benthic Foraminifera is a unique, comprehensive reference work on the larger benthic foraminifera. This second edition is substantially revised, including extensive re-analysis of the most recent work on Cenozoic forms. It provides documentation of the biostratigraphic ranges and paleoecological significance of the larger foraminifera, which is essential for understanding many major oil-bearing sedimentary basins. In addition, it offers a palaeogeographic interpretation of the shallow marine late Paleozoic to Cenozoic world. Marcelle K. BouDagher-Fadel collects and significantly adds to the information already published on the larger benthic foraminifera. New research in the Far East, the Middle East, South Africa, Tibet and the Americas has provided fresh insights into the evolution and palaeographic significance of these vital reef-forming forms. With the aid of new and precise biostratigraphic dating, she presents revised phylogenies and ranges of the larger foraminifera. The book is illustrated throughout, with examples of different families and groups at the generic levels. Key species are discussed and their biostratigraphic ranges are depicted in comparative charts.

51 citations


Journal ArticleDOI
TL;DR: In this paper, a diversity index based on living benthic foraminifera is proposed to assess the EcoQ of marine waters using the diversity index Exp(H' bc ) based on BFA.

48 citations


Journal ArticleDOI
TL;DR: In this paper, a new Cenozoic record of sulfur isotopes, using carbonate-associated sulfate hosted in the calcite lattice of single-species foraminifera, is presented.
Abstract: Understanding the changes in, and drivers of, isotopic variability of sulfur in seawater sulfate (δ34SSO4-sw) over geological time remains a long-standing goal, particularly because of the coupling between the biogeochemical sulfur and carbon cycles. The early Cenozoic has remained enigmatic in this regard, as the existing seawater sulfate isotopic records appear to be decoupled from the well-defined carbon isotope composition of the ocean. Here, we present a new Cenozoic record of sulfur isotopes, using carbonate-associated sulfate hosted in the calcite lattice of single-species foraminifera. The vastly improved stratigraphy afforded by this record demonstrates that carbon and sulfur cycles, as recorded by their isotopes, are not fully decoupled in the early Cenozoic. With a model driven by partial coupling of the carbon and sulfur cycles, we demonstrate that a change in sulfur isotopic fractionation of the pyrite burial flux best explains the large increase in δ34SSO4-sw ~53 million years ago (Ma) and the subsequent long steady state. We suggest that the locus of pyrite burial changed from shallow epicontinental seas and shelf environments to more open-ocean sediments around 53 Ma. Loss of extensive shelf environments corresponds to Cretaceous–Palaeogene sea-level changes and tectonic reorganization, occurring as the Himalayan arc first collided with Asia. A Cenozoic reconstruction of the δ34S of marine sulfate suggests a shift in the locus of pyrite burial from shallow seas to the open ocean during the early Eocene.

43 citations


Journal ArticleDOI
TL;DR: A new, quantitative biological proxy for determining ocean paleo-oxygen concentrations is described: the surface area of pores in the tests of deep-sea benthic foraminifera collected alive from 22 locations, demonstrating a strong, negative logarithmic correlation between bottom-water oxygen concentrations and pore surface area.
Abstract: The negative consequences of fossil fuel burning for the oceans will likely include warming, acidification and deoxygenation, yet predicting future deoxygenation is difficult. Sensitive proxies for oxygen concentrations in ancient deep-ocean bottom-waters are needed to learn from patterns of marine deoxygenation during global warming conditions in the geological past. Understanding of past oxygenation effects related to climate change will better inform us about future patterns of deoxygenation. Here we describe a new, quantitative biological proxy for determining ocean paleo-oxygen concentrations: the surface area of pores (used for gas exchange) in the tests of deep-sea benthic foraminifera collected alive from 22 locations (water depths: 400 to 4100 m) at oxygen levels ranging from ~ 2 to ~ 277 μmol/l. This new proxy is based on species that are widely distributed geographically, bathymetrically and chronologically, and therefore should have broad applications. Our calibration demonstrates a strong, negative logarithmic correlation between bottom-water oxygen concentrations and pore surface area, indicating that pore surface area of fossil epifaunal benthic foraminifera can be used to reconstruct past changes in deep ocean oxygen and redox levels.

37 citations


Journal ArticleDOI
TL;DR: In this article, the authors developed a Late Pleistocene and Holocene stratigraphic framework, using stable oxygen and carbon isotope signatures (δ^(18)O, δ(13)C) of benthic and planktic foraminifera, the mineralogical and carbon-oxide composition of methane-derived authigenic carbonate (MDAC) and sediment geochemical data of ten sediment cores to assess methane seepage variability on Vestnesa Ridge.

35 citations


Journal ArticleDOI
TL;DR: In this article, a long outcrop section in the Jeirankechmez river valley, Azerbaijan, near the western coast of the Caspian Sea has been studied, including the upper part of the Pliocene Productive Series and overlying Plio-Pleistocene Akchagylian and Apsheronian regional stages.

Journal ArticleDOI
TL;DR: In this article, the neodymium isotopic composition of mixed planktonic foraminifera from core MD77-176 from an intermediate depth in the Northern Indian Ocean was used to reconstruct the past evolution of intermediate water during deglaciation.

Journal ArticleDOI
TL;DR: In the Huangliu Formation, the O-18 and C-13 stable isotopes suggest that dolomitization was mediated by slightly modified seawater, and the Sr-87/Sr-86 ratios from the dolostones suggest that the original carbonate sediments accumulated in water that was < 30 m deep.

Journal ArticleDOI
TL;DR: In this article, the authors explore how varying bottom water conditions across a large hydrographic gradient in the Baltic Sea correlate with benthic foraminiferal faunal assemblages and the geochemical composition of their calcite tests.
Abstract: . Current climate and environmental changes strongly affect shallow marine and coastal areas like the Baltic Sea. This has created a need for a context to understand the severity and potential outcomes of such changes. The context can be derived from paleoenvironmental records during periods when comparable events happened in the past. In this study, we explore how varying bottom water conditions across a large hydrographic gradient in the Baltic Sea affect benthic foraminiferal faunal assemblages and the geochemical composition of their calcite tests. We have conducted both morphological and molecular analyses of the faunas and we evaluate how the chemical signatures of the bottom waters are recorded in the tests of several species of benthic foraminifera. We focus on two locations, one in the Kattegat (western Baltic Sea) and one in Hano Bay (southern Baltic Sea). We show that seawater Mn∕Ca , Mg∕Ca , and Ba∕Ca ( Mn∕Casw , Mg∕Casw , and Ba∕Casw ) variations are mainly controlled by dissolved oxygen concentration and salinity. Their respective imprints on the foraminiferal calcite demonstrate the potential of Mn∕Ca as a proxy for hypoxic conditions, and Ba∕Ca as a proxy for salinity in enclosed basins such as the Baltic Sea. The traditional use of Mg∕Ca as a proxy to reconstruct past seawater temperatures is not recommended in the region, as it may be overprinted by the large variations in salinity (specifically on Bulimina marginata), Mg∕Casw , and possibly also the carbonate system. Salinity is the main factor controlling the faunal assemblages: a much more diverse fauna occurs in the higher-salinity ( ∼32 ) Kattegat than in the low-salinity ( ∼15 ) Hano Bay. Molecular identification shows that only Elphidium clavatum occurs at both locations, but other genetic types of both genera Elphidium and Ammonia are restricted to either low- or high-salinity locations. The combination of foraminiferal geochemistry and environmental parameters demonstrates that in a highly variable setting like the Baltic Sea, it is possible to separate different environmental impacts on the foraminiferal assemblages and therefore use Mn∕Ca , Mg∕Ca , and Ba∕Ca to reconstruct how specific conditions may have varied in the past.

Journal ArticleDOI
TL;DR: The remarkable similarity among records from different ocean regions suggests that the degree of ocean carbonate change was globally near uniform, and attribute the global extent of surface ocean acidification to elevated atmospheric carbon dioxide levels during the main phase of the PETM.
Abstract: Geologically abrupt carbon perturbations such as the Palaeocene-Eocene Thermal Maximum (PETM, approx. 56 Ma) are the closest geological points of comparison to current anthropogenic carbon emissions. Associated with the rapid carbon release during this event are profound environmental changes in the oceans including warming, deoxygenation and acidification. To evaluate the global extent of surface ocean acidification during the PETM, we present a compilation of new and published surface ocean carbonate chemistry and pH reconstructions from various palaeoceanographic settings. We use boron to calcium ratios (B/Ca) and boron isotopes (δ11B) in surface- and thermocline-dwelling planktonic foraminifera to reconstruct ocean carbonate chemistry and pH. Our records exhibit a B/Ca reduction of 30-40% and a δ11B decline of 1.0-1.2‰ coeval with the carbon isotope excursion. The tight coupling between boron proxies and carbon isotope records is consistent with the interpretation that oceanic absorption of the carbon released at the onset of the PETM resulted in widespread surface ocean acidification. The remarkable similarity among records from different ocean regions suggests that the degree of ocean carbonate change was globally near uniform. We attribute the global extent of surface ocean acidification to elevated atmospheric carbon dioxide levels during the main phase of the PETM.This article is part of a discussion meeting issue 'Hyperthermals: rapid and extreme global warming in our geological past'.

Journal ArticleDOI
TL;DR: In this article, the authors investigated the palaeoenvironmental resolution potential provided by benthic foraminifera and ostracoda within a Pleistocene lagoonal succession of the Romagna coastal plain (northern Italy).
Abstract: . Integrated analyses of multiple groups of microfossils are frequently performed to unravel the palaeoenvironmental evolution of subsurface coastal successions, where the complex interaction among several palaeoecological factors can be detected with benthic assemblages. This work investigates the palaeoenvironmental resolution potential provided by benthic foraminifera and ostracoda within a Pleistocene lagoonal succession of the Romagna coastal plain (northern Italy). Quantitative approaches and statistical techniques have been applied to both groups in order to understand the main factors that controlled the composition of assemblages and compare the palaeoecological record provided by single fossil groups. The two faunal groups are characterized by the high dominance of opportunistic species (Ammonia tepida–Ammonia parkinsoniana and Cyprideis torosa); however, detailed palaeoecological information is inferred from less common taxa. Benthic foraminiferal assemblages are mainly determined by the frequencies of abnormal individuals and species related to high concentrations of organic matter, showing two assemblages: a stressed assemblage, consistent with a brackish-water environment subject to salinity and oxygen fluctuations, and an unstressed assemblage, which indicates more stable conditions. Despite the lower number of species, ostracoda show more significant differences in terms of species composition and ecological structure between their three assemblages, formed in response to a salinity gradient and indicative of inner, central, and outer lagoon conditions. The stratigraphic distribution of ostracod assemblages shows a general transgressive–regressive trend with minor fluctuations, whereas benthic foraminifera highlight the presence of a significant palaeoenvironmental stress. In this case, the higher abundance along the stratigraphic succession, the higher differentiation of the assemblages, and the well-defined relationship between taxa and ecological parameters determine Ostracoda as the most reliable fossil group for precise palaeoenvironmental reconstructions. Nevertheless, benthic foraminifera indicate palaeoenvironmental stress and can be used to refine the environmental interpretation in the presence of monospecific ostracod assemblages.

Journal ArticleDOI
TL;DR: In this paper, the authors used Ca and Sr isotopes (δ44/40Ca and 87Sr/86Sr), coupled with elemental ratios, to better understand the water source apportionment and carbonate output in the Coorong, Lower Lakes and Murray Mouth Estuary, which represents the terminus of Australia's longest river system.

Journal ArticleDOI
TL;DR: In this article, the authors reconstructed the climate evolution of the last 2700 years in the central Mediterranean Sea from marine sediment records by integrating planktonic foraminifera and geochemical signals.

Journal ArticleDOI
TL;DR: In the early Mesozoic, Dinoflagellates and coccolithophores are two of the most important groups of phytoplankton in the modern oceans as mentioned in this paper, and their evolution is linked to a positive carbon isotope shift and an interval of enhanced productivity driven by a shift to a more humid climate, enhanced continental weathering and nutrient flux, or by changes in ocean circulation and upwelling.

Journal ArticleDOI
TL;DR: Benthic and planktonic foraminifera, stable isotopes and other geochemical and sedimentological parameters have been investigated in a sediment core from Vestnesa Ridge in order to reconstruct the palaeoceanographic and palaeoenvironmental evolution of the eastern Fram Strait during the last 14,000 years as mentioned in this paper.

Journal ArticleDOI
TL;DR: In this article, three detailed sections of the Tortonian/Messinian sedimentary succession were measured and sampled in three different basins (from west to east: Chania, Heraklion, and Sitia).

Journal ArticleDOI
TL;DR: In this article, a multiproxy approach was used to quantitatively constrain bottom water carbonate chemistry and oxygenation to estimate historic changes in respired carbon storage, and the results suggest enhanced mixing of lower Circumpolar Deep Water (LCDW) to EEP mid water depths and provide evidence for the importance of circulation for oceanic-atmospheric CO2 exchange.


Journal ArticleDOI
TL;DR: Radiocarbon signatures measured for organic carbon in differing grain-size sediment fractions and foraminifera in a sediment core retrieved from the southwest Iberian margin spanning the last ~25,000 yr underscore an important link between regional hydrodynamics and interpretations of down-core sedimentary proxies.
Abstract: Ocean dynamics served an important role during past dramatic climate changes via impacts on deep-ocean carbon storage. Such changes are recorded in sedimentary proxies of hydrographic change on continental margins, which lie at the ocean–atmosphere–earth interface. However, interpretations of these records are challenging, given complex interplays among processes delivering particulate material to and from ocean margins. Here we report radiocarbon (14C) signatures measured for organic carbon in differing grain-size sediment fractions and foraminifera in a sediment core retrieved from the southwest Iberian margin, spanning the last ~25,000 yr. Variable differences of 0–5000 yr in radiocarbon age are apparent between organic carbon in differing grain-sizes and foraminifera of the same sediment layer. The magnitude of 14C differences co-varies with key paleoceanographic indices (e.g., proximal bottom-current density gradients), which we interpret as evidence of Atlantic–Mediterranean seawater exchange influencing grain-size specific carbon accumulation and translocation. These findings underscore an important link between regional hydrodynamics and interpretations of down-core sedimentary proxies.

Journal ArticleDOI
TL;DR: In this article, the authors explore the use of Mg/Ca ratios in six Arctic Ocean benthic foraminifera species as bottom water palaeothermometers.

Journal ArticleDOI
TL;DR: Evaluating the organic matter accumulation effects on the foraminiferal distribution in the Itaipu lagoon (Brazil) finds that low density or absence of living foraminifera corresponds to a low quality organic matter enriched area (North, Southwest and Centre).

Journal ArticleDOI
TL;DR: The results of the present study enhance future high-resolution paleo-environmental interpretations based on benthic foraminifera in transitional environments along the English Channel and southern North Sea.

Journal ArticleDOI
TL;DR: In this paper, the authors provide a comprehensive ancient sedimentary DNA record of both fossilizing and non-fossilizing protists and their response to OMZ variability in the NE Arabian Sea over the last 43 ka.

Journal ArticleDOI
TL;DR: This work targets planktonic foraminifera, a group of protists whose known morphological diversity is limited, taxonomically resolved and linked to ribosomal DNA barcodes, and identifies 69 genetic types belonging to 41 morphotaxa in the metabarcoding dataset.
Abstract: Since the advent of DNA metabarcoding surveys, the planktonic realm is considered a treasure trove of diversity, inhabited by a small number of abundant taxa, and a hugely diverse and taxonomically uncharacterized consortium of rare species. Here we assess if the apparent underestimation of plankton diversity applies universally. We target planktonic foraminifera, a group of protists whose known morphological diversity is limited, taxonomically resolved and linked to ribosomal DNA barcodes. We generated a pyrosequencing dataset of ~100,000 partial 18S rRNA foraminiferal sequences from 32 size fractioned photic-zone plankton samples collected at 8 stations in the Indian and Atlantic Oceans during the Tara Oceans expedition (2009–2012). We identified 69 genetic types belonging to 41 morphotaxa in our metabarcoding dataset. The diversity saturated at local and regional scale as well as in the three size fractions and the two depths sampled indicating that the diversity of foraminifera is modest and finite. The large majority of the newly discovered lineages occur in the small size fraction, neglected by classical taxonomy. These unknown lineages dominate the bulk [>0.8 µm] size fraction, implying that a considerable part of the planktonic foraminifera community biomass has its origin in unknown lineages.

Journal ArticleDOI
TL;DR: In this article, the nitrogen isotope ratios (N) of planktic foraminifera collected from upper-ocean net tows (surface to 200m), moored sediment traps, and core-top sediments at the Bermuda Time-series Site in the northern Sargasso Sea between 2009 and 2013 were reported.