47 results on '"Head, Martin"'
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2. Critique of Proposals 258–260 to eliminate contradiction between Articles 11.7 and 11.8 and to equate non-fossil with fossil names of dinophytes for purposes of priority, by Elbrächter & al. (2023), and ensuing recommendations
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Head, Martin J., Fensome, Robert A., Mertens, Kenneth, Herendeen, Patrick S., Head, Martin J., Fensome, Robert A., Mertens, Kenneth, and Herendeen, Patrick S.
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- 2024
- Full Text
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3. Dinoflagellate cysts and other marine palynomorphs from Lower Eocene through Lower Pliocene sediments of the Labrador Sea and Baffin Bay
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Head, Martin James
- Subjects
551 ,Palynoflora ,Oceanic ,Neritic ,Temperature - Abstract
Cenozoic sediments recovered during Leg 105 of the Ocean Drilling Program in Baffin Bay (Site 645) and the Labrador Sea (Sites 646 and 647) have yielded a persistent record of dinoflagellates and other marine palynomorphs. Hole 647A in the Labrador Sea contains an almost complete deep-water record of early Eocene through early late Oligocene sedimentation. Dinoflagellate assemblages indicate outer neritic to oceanic conditions throughout, but with possible increased influence from shelf environments during the early Eocene. Lower Eocene dinoflagellate assemblages are similar to coeval assemblages from the Rockall Plateau, but those from the middle through upper Eocene have mixed affinities, and are perhaps related to intensification of the proto-Gulf Stream. Oligocene dinoflagellate assemblages suggest the influence of both Arctic and North Atlantic watermasses at this site. A diverse marine palynoflora was recovered from upper Miocene and lowermost Pliocene sediments of Hole 646B in the central Labrador Sea. Palynomorph assemblages are thought to be largely allochthonous and may reflect changing bottom-water paleocurrents. The dinoflagellate flora consists of both oceanic and neritic species and indicates temperate surface-water conditions. Lower through lower upper Miocene dinoflagellates recovered from Baffin Bay (Hole 645E) indicate a cool-water, neritic environment. Assemblages have North Atlantic and Norwegian Sea affinities, but also contain notable protoperidiniacean elements. Dinoflagellate biostratigraphy estimates initiation of ice rafting in Baffin Bay at between 7.4 and 9.5 Ma. Increased terrigenous influx and apparent disappearance of certain dinoflagellate taxa occur in the middle to late Miocene and may be related to oceanographic changes or climatic deterioration. The erection of three new dinoflagellate genera, 19 new dinoflagellate species, and three new acritarch species, are among the many taxonomic proposals contained in this study of the Miocene. Several Miocene holotypes from Japan, have also been studied and compared to the Leg 105 material.
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- 1990
4. The Great Acceleration is real and provides a quantitative basis for the proposed Anthropocene Series/Epoch
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Head, Martin J., Steffen, Will, Fagerlind, David, Waters, Colin N., Poirier, Clement, Syvitski, Jaia, Zalasiewicz, Jan A., Barnosky, Anthony D., Cearreta, Alejandro, Jeandel, Catherine, Leinfelder, Reinhold, McNeill, J. R., Rose, Neil L., Summerhayes, Colin, Wagreich, Michael, Zinke, Jens, Head, Martin J., Steffen, Will, Fagerlind, David, Waters, Colin N., Poirier, Clement, Syvitski, Jaia, Zalasiewicz, Jan A., Barnosky, Anthony D., Cearreta, Alejandro, Jeandel, Catherine, Leinfelder, Reinhold, McNeill, J. R., Rose, Neil L., Summerhayes, Colin, Wagreich, Michael, and Zinke, Jens
- Abstract
The Anthropocene was conceptualized in 2000 to reflect the extensive impact of human activities on our planet, and subsequent detailed analyses have revealed a substantial Earth System response to these impacts beginning in the mid-20th century. Key to this understanding was the discovery of a sharp upturn in a multitude of global socio-economic indicators and Earth System trends at that time; a phenomenon termed the ‘Great Acceleration’. It coincides with massive increases in global human-consumed energy and shows the Earth System now on a trajectory far exceeding the earlier variability of the Holocene Epoch, and in some respects the entire Quaternary Period. The evaluation of geological signals similarly shows the mid-20th century as representing the most appropriate inception for the Anthropocene. A recent mathematical analysis has nonetheless challenged the significance of the original Great Acceleration data. We examine this analytical approach and reiterate the robustness of the original data in supporting the Great Acceleration, while emphasizing that intervals of rapid growth are inevitably time-limited, as recognised at the outset. Moreover, the exceptional magnitude of this growth remains undeniable, reaffirming the centrality of the Great Acceleration in justifying a formal chronostratigraphic Anthropocene at the rank of series/epoch.
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- 2022
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5. The Standard Auxiliary Boundary Stratotype: a proposed replacement for the Auxiliary Stratotype Point in supporting a Global boundary Stratotype Section and Point (GSSP)
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Head, Martin J., Aubry, Marie-Pierre, Piller, Werner E., Walker, Mike, Head, Martin J., Aubry, Marie-Pierre, Piller, Werner E., and Walker, Mike
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Auxiliary boundary stratotypes have unquestionable value in extending the knowledge of a Global boundary Stratotype Section and Point (GSSP) between continents, biogeographic provinces, climatic zones, depositional facies and preservational states. Two kinds of such stratotypes are in use, the Auxiliary Stratotype Point and the Auxiliary Stratotype Section, although only the Auxiliary Stratotype Point is recognised by the International Commission on Stratigraphy (ICS). The Standard Auxiliary Boundary Stratotype, which is based on the Auxiliary Stratotype Section, is proposed here as a formal replacement for the Auxiliary Stratotype Point. As such, it would provide a detailed complementary expression of the boundary interval without the designation of a specific point – no such points can replicate the precise level defined by a GSSP either conceptually or in practice. We recommend that requirements for future Standard Auxiliary Boundary Stratotypes broadly follow ICS guidelines for GSSPs but be applied with greater flexibility. Past practice reveals inconsistency in the protocols used for approving such auxiliary boundary stratotypes. We propose that in future they require approval by the respective ICS subcommission. More than one Standard Auxiliary Boundary Stratotype may support a single GSSP but restraint should be exercised in approving them, and each will always be subordinate to the GSSP itself.
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- 2022
6. Epochs, events and episodes: Marking the geological impact of humans
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Geología, Geologia, Waters, Colin N., Williams, Mark, Zalasiewicz, Jan, Turner, Simon D., Barnosky, Anthony D., Head, Martin J., Wing, Scott L., Wagreich, Michael, Steffen, Will, Summerhayes, Colin P., Cundy, Andrew B., Zinke, Jens, Fialkiewicz-Koziel, Barbara, Leinfelder, Reinhold, Haff, Peter K., McNeill, J. R., Rose, Neil L., Hajdas, Irka, McCarthy, Francine M. G., Cearreta Bilbao, Alejandro, Galuszka, Agnieszka, Syvitski, Jaia, Han, Yongming, An, Zhisheng, Fairchild, Ian J., Ivar do Sul, Juliana A., Jeandel, Catherine, Geología, Geologia, Waters, Colin N., Williams, Mark, Zalasiewicz, Jan, Turner, Simon D., Barnosky, Anthony D., Head, Martin J., Wing, Scott L., Wagreich, Michael, Steffen, Will, Summerhayes, Colin P., Cundy, Andrew B., Zinke, Jens, Fialkiewicz-Koziel, Barbara, Leinfelder, Reinhold, Haff, Peter K., McNeill, J. R., Rose, Neil L., Hajdas, Irka, McCarthy, Francine M. G., Cearreta Bilbao, Alejandro, Galuszka, Agnieszka, Syvitski, Jaia, Han, Yongming, An, Zhisheng, Fairchild, Ian J., Ivar do Sul, Juliana A., and Jeandel, Catherine
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Event stratigraphy is used to help characterise the Anthropocene as a chronostratigraphic concept, based on analogous deep-time events, for which we provide a novel categorization. Events in stratigraphy are distinct from extensive, time-transgressive ‘episodes’ – such as the global, highly diachronous record of anthropogenic change, termed here an Anthropogenic Modification Episode (AME). Nested within the AME are many geologically correlatable events, the most notable being those of the Great Acceleration Event Array (GAEA). This isochronous array of anthropogenic signals represents brief, unique events evident in geological deposits, e.g.: onset of the radionuclide ‘bomb-spike’; appearance of novel organic chemicals and fuel ash particles; marked changes in patterns of sedimentary deposition, heavy metal contents and carbon/nitrogen isotopic ratios; and ecosystem changes leaving a global fossil record; all around the mid-20th century. The GAEA reflects a fundamental transition of the Earth System to a new state in which many parameters now lie beyond the range of Holocene variability. Globally near-instantaneous events can provide robust primary guides for chronostratigraphic boundaries. Given the intensity, magnitude, planetary significance and global isochroneity of the GAEA, it provides a suitable level for recognition of the base of the Anthropocene as a series/epoch.
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- 2022
7. Formal ratification of subseries for the Pleistocene Series of the Quaternary System
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Head, Martin J., Pillans, Brad, Zalasiewicz, Jan A., the ICS Subcommission on Quaternary Stratigraphy, Head, Martin J., Pillans, Brad, Zalasiewicz, Jan A., and the ICS Subcommission on Quaternary Stratigraphy
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The Pleistocene Series/Epoch of the Quaternary System/Period has been divided unofficially into three subseries/subepochs since at least the 1870s. On 30th January, 2020, the Executive Committee of the International Union of Geological Sciences ratified two proposals approved by the International Commission on Stratigraphy formalizing: 1) the Lower Pleistocene Subseries, comprising the Gelasian Stage and the superjacent Calabrian Stage, with a base defined by the GSSP for the Gelasian Stage, the Pleistocene Series, and the Quaternary System, and currently dated at 2.58 Ma; and 2) the term Upper Pleistocene, at the rank of subseries, with a base currently undefined but provisionally dated at ~129 ka. Defining the Upper Pleistocene Subseries and its corresponding stage with a GSSP is in progress. The Middle Pleistocene Subseries is defined by the recently ratified GSSP for the Chibanian Stage currently dated at 0.774 Ma. These ratifications complete the official division of the Pleistocene into three subseries/subepochs, in uniformity with the similarly subdivided Holocene Series/Epoch.
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- 2021
8. The Anthropocene: Comparing Its Meaning in Geology (Chronostratigraphy) with Conceptual Approaches Arising in Other Disciplines
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Geología, Geologia, Zalasiewicz, Jan, Waters, Colin N., Ellis, Erle C., Head, Martin J., Vidas, Davor, Steffen, Will, Thomas, Julia Adeney, Horn, Eva, Summerhayes, Colin P., Leinfelder, Reinhold, McNeill, J. R., Galuszka, Agnieszka, Williams, Mark, Barnosky, Anthony D., Richter, Daniel de B., Gibbard, Philip L., Syvitski, Jaia, Jeandel, Catherine, Cearreta Bilbao, Alejandro, Cundy, Andrew B., Fairchild, Ian J., Rose, Neil L., Ivar do Sul, Juliana A., Shotyk, William, Turner, Simon, Wagreich, Michael, Zinke, Jens, Geología, Geologia, Zalasiewicz, Jan, Waters, Colin N., Ellis, Erle C., Head, Martin J., Vidas, Davor, Steffen, Will, Thomas, Julia Adeney, Horn, Eva, Summerhayes, Colin P., Leinfelder, Reinhold, McNeill, J. R., Galuszka, Agnieszka, Williams, Mark, Barnosky, Anthony D., Richter, Daniel de B., Gibbard, Philip L., Syvitski, Jaia, Jeandel, Catherine, Cearreta Bilbao, Alejandro, Cundy, Andrew B., Fairchild, Ian J., Rose, Neil L., Ivar do Sul, Juliana A., Shotyk, William, Turner, Simon, Wagreich, Michael, and Zinke, Jens
- Abstract
The term Anthropocene initially emerged from the Earth System science community in the early 2000s, denoting a concept that the Holocene Epoch has terminated as a consequence of human activities. First associated with the onset of the Industrial Revolution, it was then more closely linked with the Great Acceleration in industrialization and globalization from the 1950s that fundamentally modified physical, chemical, and biological signals in geological archives. Since 2009, the Anthropocene has been evaluated by the Anthropocene Working Group, tasked with examining it for potential inclusion in the Geological Time Scale. Such inclusion requires a precisely defined chronostratigraphic and geochronological unit with a globally synchronous base and inception, with the mid-twentieth century being geologically optimal. This reflects an Earth System state in which human activities have become predominant drivers of modifications to the stratigraphic record, making it clearly distinct from the Holocene. However, more recently, the term Anthropocene has also become used for different conceptual interpretations in diverse scholarly fields, including the environmental and social sciences and humanities. These are often flexibly interpreted, commonly without reference to the geological record, and diachronous in time; they often extend much further back in time than the mid-twentieth century. These broader conceptualizations encompass wide ranges and levels of human impacts and interactions with the environment. Here, we clarify what the Anthropocene is in geological terms and compare the proposed geological (chronostratigraphic) definition with some of these broader interpretations and applications of the term "Anthropocene," showing both their overlaps and differences.
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- 2021
9. Subseries/Subepochs approved as a formal rank in the international stratigraphic guide
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Aubry, Marie-Pierre, Head, Martin J., Piller, Werner E., Berggren, William A., Aubry, Marie-Pierre, Head, Martin J., Piller, Werner E., and Berggren, William A.
- Abstract
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Aubry, M., Head, M. J., Piller, W. E., & Berggren, W. A. Subseries/Subepochs approved as a formal rank in the international stratigraphic guide. Episodes, 43(4), (2020): 1041-1044, doi:10.18814/epiiugs/2020/020066., The International Subcommission on Stratigraphic Classification, as the constituent body of the International Commission on Stratigraphy (ICS) responsible for the International Stratigraphic Guide, has voted to include the subseries/ subepoch as a formal rank in the next edition of the Guide. This acknowledges the recent ratification of formal subseries and their corresponding stages for the Holocene Series/Epoch but allows individual subcommissions within ICS the freedom to decide whether or not to adopt this rank for their particular stratigraphic/time interval., We are grateful to the ISSC membership for discussions and to Secretary Jochen Erbacher for organizing the vote; to Mike Walker for sharing an unpublished manuscript with us; to the many colleagues who have expressed their support for formalization of subseries; and to Dennis Kent and an anonymous reviewer for their reviews of the manuscript.
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- 2021
10. Formal ratification of subseries for the Pleistocene Series of the Quaternary System
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Geomorfologie, Head, Martin J., Pillans, Brad, Zalasiewicz, Jan A., the ICS Subcommission on Quaternary Stratigraphy, Geomorfologie, Head, Martin J., Pillans, Brad, Zalasiewicz, Jan A., and the ICS Subcommission on Quaternary Stratigraphy
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- 2021
11. Taxonomy and nomenclature in palaeopalynology: basic principles, current challenges and future perspectives
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Gravendyck, Julia, Fensome, Robert A., Head, Martin J., Herendeen, Patrick S., Riding, James B., Bachelier, Julien B., Turland, Nicholas J., Gravendyck, Julia, Fensome, Robert A., Head, Martin J., Herendeen, Patrick S., Riding, James B., Bachelier, Julien B., and Turland, Nicholas J.
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Effective communication of taxonomic concepts is crucial to meaningful application in all biological sciences, and thus the development and following of best practices in taxonomy and the formulation of clear and practical rules of nomenclature underpin a wide range of scientific studies. The International Code of Nomenclature for algae, fungi and plants (the Code), currently the Shenzhen Code of 2018, provides these rules. Although early versions of the Code were designed mainly with extant plants in mind, the Code has been increasingly used for fossil plants and, in recent decades, for organic-walled microfossils, the study of which is called palaeopalynology, or simply palynology. However, rules embodied in the Code do not fully reflect the needs and practices of this discipline; and taxonomic practices between fossil applications, especially in palynology, have tended to diverge from practices for extant plants. Differences in these rules and practices present specific challenges. We therefore review the Shenzhen Code as it applies to palynology, clarifying procedures and recommending approaches based on best practices, for example, in the designation and use of nomenclatural types. The application of nomenclatural types leads to taxonomic stability and precise communication, and lost or degraded types are therefore problematic because they remove the basis for understanding a taxon. Such problems are addressed using examples from the older European literature in which type specimens are missing or degraded. A review of the three most important conventions for presenting palynological taxonomic information, synonymies, diagnoses/descriptions and illustrations, concludes with recommendations of best practices. Palynology continues to play an important role in biostratigraphy, palaeoenvironmental analyses, and evolutionary studies, and is contributing increasingly to our understanding of past climates and ocean systems. To contribute with full potential to such ap
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- 2021
12. Formal ratification of subseries for the Pleistocene Series of the Quaternary System
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Beu, Alan G., Cohen, Kim M., Gibbard, Philip L., Head, Martin J., Knudsen, Karen Luise, Kolfschoten, Thijs van, Lirer, Fabrizio, Litt, Thomas, Liu, Jaiqi, Marks, Leszek, McManus, Jerry F., Pillans, Brad, Piotrowski, Jan A., Räsänen, Matti, Rasmussen, Sune O., Saito, Yoshiki, Tesakov, Alexey, Turner, Charles, Walker, Mike, Zalasiewicz, Jan A., Zazo, Caridad, Beu, Alan G., Cohen, Kim M., Gibbard, Philip L., Head, Martin J., Knudsen, Karen Luise, Kolfschoten, Thijs van, Lirer, Fabrizio, Litt, Thomas, Liu, Jaiqi, Marks, Leszek, McManus, Jerry F., Pillans, Brad, Piotrowski, Jan A., Räsänen, Matti, Rasmussen, Sune O., Saito, Yoshiki, Tesakov, Alexey, Turner, Charles, Walker, Mike, Zalasiewicz, Jan A., and Zazo, Caridad
- Abstract
The Pleistocene Series/Epoch of the Quaternary System/Period has been divided unofficially into three subseries/subepochs since at least the 1870s. On 30 January, 2020, the Executive Committee of the International Union of Geological Sciences ratified two proposals approved by the International Commission on Stratigraphy formalizing: 1) the Lower Pleistocene Subseries, comprising the Gelasian Stage and the superjacent Calabrian Stage, with a base defined by the GSSP for the Gelasian Stage, the Pleistocene Series, and the Quaternary System, and currently dated at 2.58 Ma; and 2) the term Upper Pleistocene, at the rank of subseries, with a base currently undefined but provisionally dated at ~129 ka. Defining the Upper Pleistocene Subseries and its corresponding stage with a GSSP is in progress. The Middle Pleistocene Subseries is defined by the recently ratified GSSP for the Chibanian Stage currently dated at 0.774 Ma. These ratifications complete the official division of the Pleistocene into three subseries/subepochs, in uniformity with the similarly subdivided Holocene Series/Epoch.
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- 2021
13. An overview and brief description of common marine organic-walled dinoflagellate cyst taxa occurring in surface sediments of the Northern Hemisphere
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Van Nieuwenhove, Nicolas, Head, Martin J., Limoges, Audrey, Pospelova, Vera, Mertens, Kenneth, Matthiessen, Jens, De Schepper, Stijn, De Vernal, Anne, Eynaud, Frédérique, Londeix, Laurent, Marret, Fabienne, Penaud, Aurélie, Radi, Taoufik, Rochon, André, Van Nieuwenhove, Nicolas, Head, Martin J., Limoges, Audrey, Pospelova, Vera, Mertens, Kenneth, Matthiessen, Jens, De Schepper, Stijn, De Vernal, Anne, Eynaud, Frédérique, Londeix, Laurent, Marret, Fabienne, Penaud, Aurélie, Radi, Taoufik, and Rochon, André
- Abstract
Organic-walled resting cysts of planktonic dinoflagellates occur commonly in modern marine sediment where they represent, with rare exceptions, the only geologically preservable part of the life cycle. Although many species do not produce fossilizable resting cysts, upper Quaternary sediments contain a diverse cyst record that is used frequently for paleoenvironmental reconstruction and stratigraphic analysis. Reconstructions of past sea-surface conditions rely on an understanding of the distributions of dinoflagellate cysts in modern sediments linked to their respective environmental parameters, underpinned by sound taxonomy and standardized nomenclature. Stratigraphic studies additionally require knowledge of morphological details to distinguish extant from similar extinct taxa. Here, 51 dinoflagellate cyst species and two informal cyst morphotypes that are commonly encountered during routine palynological analysis of upper Quaternary marine sediments from the Northern Hemisphere are briefly described taxonomically and illustrated. In addition, their lowest stratigraphic occurrences are provided.
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- 2020
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14. A review of rare and less well known extant marine organic-walled dinoflagellate cyst taxa of the orders Gonyaulacales and Suessiales from the Northern Hemisphere
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Limoges, Audrey, Van Nieuwenhove, Nicolas, Head, Martin J., Mertens, Kenneth, Pospelova, Vera, Rochon, André, Limoges, Audrey, Van Nieuwenhove, Nicolas, Head, Martin J., Mertens, Kenneth, Pospelova, Vera, and Rochon, André
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Dinoflagellate resting cysts with rare exception produce the only discrete link between the biology of extant dinoflagellate species and their fossil record. The geological preservability of such cysts allows them to be used for quantitative paleoecological reconstructions, especially in the Quaternary, and for biostratigraphy and the calibration of molecular clocks with the geological record. This contribution reviews and updates the taxonomy of 27 uncommon dinoflagellate cyst species and morphotypes belonging to the orders Gonyaulacales and Suessiales with occurrences in upper Quaternary marine sediments of the Northern Hemisphere. Comparative descriptions and illustrations are provided along with the biological affinity of each taxon where known and lowest stratigraphic occurrence.
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- 2020
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15. A review of rare, poorly known, and morphologically problematic extant marine organic-walled dinoflagellate cyst taxa of the orders Gymnodiniales and Peridiniales from the Northern Hemisphere
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Mertens, Kenneth, Gu, Haifeng, Gurdebeke, Pieter R., Takano, Yoshihito, Clarke, Dave, Aydin, Hilal, Li, Zhen, Pospelova, Vera, Shin, Hyeon Ho, Li, Zhun, Matsuoka, Kazumi, Head, Martin J., Mertens, Kenneth, Gu, Haifeng, Gurdebeke, Pieter R., Takano, Yoshihito, Clarke, Dave, Aydin, Hilal, Li, Zhen, Pospelova, Vera, Shin, Hyeon Ho, Li, Zhun, Matsuoka, Kazumi, and Head, Martin J.
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Dinoflagellates are a major component of the modern plankton. Of the 2192 species of marine free-living dinoflagellates presently described, an increasing number are being shown to produce resting cysts (probably hypnozygotes) within their life cycle. With rare exception, only the resting cysts fossilize, so they are of central importance in tracing the history of dinoflagellates through geological time. Cysts of many of the more common dinoflagellate species have distinctive morphologies allowing their geographic and stratigraphic occurrences to be traced. An ever-increasing number of taxa are also being shown to produce distinctive cysts, potentially increasing our knowledge of the diverse representation of dinoflagellates through time. Here the organic-walled cysts of 73 rare, poorly known or morphologically problematic marine dinoflagellate cyst species belonging to the orders Gymnodiniales (nine species) and Peridiniales (64 species) are reviewed, described and illustrated, and their stratigraphic ranges assessed. The names Echinidinium aculeatum and Echinidinium transparantum are validated herein.
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- 2020
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16. Extraordinary Human Energy Consumption and Resultant Geological Impacts Beginning Around 1950 CE Initiated the Proposed Anthropocene Epoch
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Geología, Geologia, Syvitski, Jaia, Waters, Colin N., Day, John, Milliman, John D., Summerhayes, Colin P., Steffen, Will, Zalasiewicz, Jan, Cearreta Bilbao, Alejandro, Galuszka, Agnieszka, Hajdas, Irka, Head, Martin J., Leinfelder, Reinhold, McNeill, J. R., Poirier, Clement, Rose, Neil L., Shotyk, William, Wagreich, Michael, Williams, Mark, Geología, Geologia, Syvitski, Jaia, Waters, Colin N., Day, John, Milliman, John D., Summerhayes, Colin P., Steffen, Will, Zalasiewicz, Jan, Cearreta Bilbao, Alejandro, Galuszka, Agnieszka, Hajdas, Irka, Head, Martin J., Leinfelder, Reinhold, McNeill, J. R., Poirier, Clement, Rose, Neil L., Shotyk, William, Wagreich, Michael, and Williams, Mark
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Growth in fundamental drivers-energy use, economic productivity and population-can provide quantitative indications of the proposed boundary between the Holocene Epoch and the Anthropocene. Human energy expenditure in the Anthropocene, similar to 22 zetajoules (ZJ), exceeds that across the prior 11,700 years of the Holocene (similar to 14.6 ZJ), largely through combustion of fossil fuels. The global warming effect during the Anthropocene is more than an order of magnitude greater still. Global human population, their productivity and energy consumption, and most changes impacting the global environment, are highly correlated. This extraordinary outburst of consumption and productivity demonstrates how the Earth System has departed from its Holocene state since similar to 1950 CE, forcing abrupt physical, chemical and biological changes to the Earth's stratigraphic record that can be used to justify the proposal for naming a new epoch-the Anthropocene. Human energy consumption and productivity have steeply risen around 1950 CE, leading to a departure from the Earth's Holocene state into the Anthropocene, suggests a quantitative analysis of humanity's influence on the Earth system.
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- 2020
17. Subseries/Subepochs approved as a formal rank in the international stratigraphic guide
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Aubry, Marie-Pierre, Head, Martin J., Piller, Werner E., Berggren, William A., Aubry, Marie-Pierre, Head, Martin J., Piller, Werner E., and Berggren, William A.
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The International Subcommission on Stratigraphic Classification, as the constituent body of the International Commission on Stratigraphy (ICS) responsible for the International Stratigraphic Guide, has voted to include the subseries/ subepoch as a formal rank in the next edition of the Guide. This acknowledges the recent ratification of formal subseries and their corresponding stages for the Holocene Series/Epoch but allows individual subcommissions within ICS the freedom to decide whether or not to adopt this rank for their particular stratigraphic/time interval.
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- 2020
18. Distribution of common modern dinoflagellate cyst taxa in surface sediments of the Northern Hemisphere in relation to environmental parameters: The new n=1968 database
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de Vernal, Anne, Radi, Taoufik, Zaragosi, Sebastien, Van Nieuwenhove, Nicolas, Rochon, André, Allan, Estelle, De Schepper, Stijn, Eynaud, Frédérique, Head, Martin J., Limoges, Audrey, Londeix, Laurent, Marret, Fabienne, Matthiessen, Jens, Penaud, Aurélie, Pospelova, Vera, Price, Andrea, Richerol, Thomas, de Vernal, Anne, Radi, Taoufik, Zaragosi, Sebastien, Van Nieuwenhove, Nicolas, Rochon, André, Allan, Estelle, De Schepper, Stijn, Eynaud, Frédérique, Head, Martin J., Limoges, Audrey, Londeix, Laurent, Marret, Fabienne, Matthiessen, Jens, Penaud, Aurélie, Pospelova, Vera, Price, Andrea, and Richerol, Thomas
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- 2020
19. Impagidinium detroitense and I.? diaphanum: Two new dinoflagellate cyst species from the Pliocene of the North Pacific Ocean, and their biostratigraphic significance
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Zorzi, Coralie, Head, Martin J., Matthiessen, Jens, de Vernal, Anne, Zorzi, Coralie, Head, Martin J., Matthiessen, Jens, and de Vernal, Anne
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- 2019
20. Citing the taxonomic literature: what a difference a year makes
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Riding, James B., Fensome, Robert A., Head, Martin J., Riding, James B., Fensome, Robert A., and Head, Martin J.
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We all know that the world of scientific publishing has changed profoundly since the onset of the digital revolution. One relatively new development is the rapid publication of scientific papers online, frequently before they are copyedited and typeset, and sometimes even before being peer reviewed (Sheldon 2018). Climate of the Past is one such journal that posts manuscripts online before they have been refereed. The purpose of doing this is to allow online discussion of a manuscript while it is under review in the conventional sense. Manuscripts may thus benefit from any useful feedback from readers as well as from the formal reviews. The above developments mean that scientific articles may appear online long before being assigned to a particular volume/issue and with final page numbers. Such assignments commonly occur in the following year when the complete volumes or issues of a journal appear in print and/ or digitally. Before the digital revolution, authors had to wait perhaps 12 months or more between acceptance and final publication. Today, just a week or two may elapse before the typescript of an accepted manuscript is available online. In most respects this revolution is good, especially now that many authors aim for metricised output targets. However, such early publication of a paper may cause complications regarding its referencing, but in most cases this does not really matter so long as the reference in a bibliography leads to the retrieval of the correct publication. For example, the paper cited below as Pound and Riding (2015) was initially issued online in 2015, prior to assignment to a volume of the Journal of the Geological Society published in 2016. Before 2016 it would have also been cited as Pound and Riding (2015) but that situation would not have lasted for long and would have affected very few, if any, citations. Electronic publication of a paper prior to assignment of the volume number and final pagination can be confusing, but in most cas
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- 2019
21. Formal Subdivision of the Holocene Series/Epoch:A Summary
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Walker, Mike, Gibbard, P.L., Head, Martin J., Berkelhammer, M., Björck, Svante, Cheng, Hai, Cwynar, L.C., Fisher, David, Gkinis, Vasileios, Long, Antony, Lowe, John, Newnham, Rewi, Rasmussen, Sune Olander, Weiss, Harvey, Walker, Mike, Gibbard, P.L., Head, Martin J., Berkelhammer, M., Björck, Svante, Cheng, Hai, Cwynar, L.C., Fisher, David, Gkinis, Vasileios, Long, Antony, Lowe, John, Newnham, Rewi, Rasmussen, Sune Olander, and Weiss, Harvey
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- 2019
22. Subdividing the Holocene Series/Epoch:formalisation of Stages/Ages and Subseries/Subepochs, and designation of GSSPs and Auxiliary Stratotypes
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Walker, M., Head, Martin J., Lowe, John, Berkelhammer, M., Björck, Svante, Cheng, H., Cwynar, L.C., Fisher, David, Gkinis, Vasileios, Long, Anthony, Newnham, Rewi, Rasmussen, Sune Olander, Weiss, Harvey, Walker, M., Head, Martin J., Lowe, John, Berkelhammer, M., Björck, Svante, Cheng, H., Cwynar, L.C., Fisher, David, Gkinis, Vasileios, Long, Anthony, Newnham, Rewi, Rasmussen, Sune Olander, and Weiss, Harvey
- Published
- 2019
23. The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments: a summary of round table discussions
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Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringué, Manuel, Dale, Barrie, De Schepper, Stijn, De Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkilä, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurélie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, André, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, Zonneveld, Karin, Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringué, Manuel, Dale, Barrie, De Schepper, Stijn, De Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkilä, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurélie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, André, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, and Zonneveld, Karin
- Abstract
We present a summary of two round-table discussions held during two subsequent workshops in Montreal (Canada) on 16 April 2014 and Ostend (Belgium) on 8 July 2015. Five species of the genus Achomosphaera Evitt 1963 and 33 of the genus Spiniferites Mantell 1850 emend. Sarjeant 1970 occuring in Pliocene to modern sediments are listed and briefly described along with remarks made by workshop participants. In addition, several holotypes and topotypes are reillustrated. Three species previously assigned to Spiniferites are here considered/accepted as belonging to other genera: Impagidinium inaequalis (Wall and Dale in Wall et al. 1973) Londeix et al. 2009, Spiniferites? rubinus (Rossignol 1962 ex Rossignol 1964) Sarjeant 1970, and Thalassiphora balcanica Baltes¸ 1971. This summary forms the basis for a set of papers that follows, where points raised during the workshops are explored in greater detail.
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- 2018
24. The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments: a summary of round table discussions
- Author
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Mertens, Kenneth, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringue, Manuel, Dale, Barrie, De Schepper, Stijn, De Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkila, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurelie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, Andre, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, Zonneveld, Karin, Mertens, Kenneth, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringue, Manuel, Dale, Barrie, De Schepper, Stijn, De Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkila, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurelie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, Andre, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, and Zonneveld, Karin
- Abstract
We present a summary of two round-table discussions held during two subsequent workshops in Montreal (Canada) on 16 April 2014 and Ostend (Belgium) on 8 July 2015. Five species of the genus Achomosphaera Evitt 1963 and 33 of the genus Spiniferites Mantell 1850 emend. Sarjeant 1970 occuring in Pliocene to modern sediments are listed and briefly described along with remarks made by workshop participants. In addition, several holotypes and topotypes are reillustrated. Three species previously assigned to Spiniferites are here considered/accepted as belonging to other genera: Impagidinium inaequalis (Wall and Dale in Wall et al. 1973) Londeix et al. 2009, Spiniferites? rubinus (Rossignol 1962 ex Rossignol 1964) Sarjeant 1970, and Thalassiphora balcanica Baltes¸ 1971. This summary forms the basis for a set of papers that follows, where points raised during the workshops are explored in greater detail.
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- 2018
- Full Text
- View/download PDF
25. Pentaplacodinium saltonense gen. et sp. nov. (Dinophyceae) and its relationship to the cyst-defined genus Operculodinium and yessotoxin-producing Protoceratium reticulatum
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Mertens, Kenneth, Carbonell-moore, Maria Consuelo, Pospeloya, Vera, Head, Martin J., Highfield, Andrea, Schroeder, Declan, Gu, Haifeng, Andree, Karl B., Fernandez, Margarita, Yamaguchi, Aika, Takano, Yoshihito, Matsuoka, Kazumi, Nezan, Elisabeth, Bilien, Gwenael, Okolodkov, Yuri, Koike, Kazuhiko, Hoppenrath, Mona, Pfaff, Maya, Pitcher, Grant, Al-muftah, Abdulrahman, Rochon, Andre, Lim, Po Teen, Leaw, Chui Pin, Lim, Zhen Fei, Ellegaard, Marianne, Mertens, Kenneth, Carbonell-moore, Maria Consuelo, Pospeloya, Vera, Head, Martin J., Highfield, Andrea, Schroeder, Declan, Gu, Haifeng, Andree, Karl B., Fernandez, Margarita, Yamaguchi, Aika, Takano, Yoshihito, Matsuoka, Kazumi, Nezan, Elisabeth, Bilien, Gwenael, Okolodkov, Yuri, Koike, Kazuhiko, Hoppenrath, Mona, Pfaff, Maya, Pitcher, Grant, Al-muftah, Abdulrahman, Rochon, Andre, Lim, Po Teen, Leaw, Chui Pin, Lim, Zhen Fei, and Ellegaard, Marianne
- Abstract
trains of a dinoflagellate from the Salton Sea, previously identified as Protoceratium reticulatum and yessotoxin producing, have been reexamined morphologically and genetically and Pentaplacodinium saltonense n. gen. et sp. is erected to accommodate this species. Pentaplacodinium saltonense differs from Protoceratium reticulatum (Claparède et Lachmann 1859) Bütschli 1885 in the number of precingular plates (five vs. six), cingular displacement (two widths vs. one), and distinct cyst morphology. Incubation experiments (excystment and encystment) show that the resting cyst of Pentaplacodinium saltonense is morphologically most similar to the cyst-defined species Operculodinium israelianum (Rossignol, 1962) Wall (1967) and O. psilatum Wall (1967). Collections of comparative material from around the globe (including Protoceratium reticulatum and the genus Ceratocorys) and single cell PCR were used to clarify molecular phylogenies. Variable regions in the LSU (three new sequences), SSU (12 new sequences) and intergenic ITS 1–2 (14 new sequences) were obtained. These show that Pentaplacodinium saltonense and Protoceratium reticulatum form two distinct clades. Pentaplacodinium saltonense forms a monophyletic clade with several unidentified strains from Malaysia. LSU and SSU rDNA sequences of three species of Ceratocorys (C. armata, C. gourreti, C. horrida) from the Mediterranean and several other unidentified strains from Malaysia form a well-supported sister clade. The unique phylogenetic position of an unidentified strain from Hawaii is also documented and requires further examination. In addition, based on the V9 SSU topology (bootstrap values >80%), specimens from Elands Bay (South Africa), originally described as Gonyaulax grindleyi by Reinecke (1967), cluster with Protoceratium reticulatum. The known range of Pentaplacodinium saltonense is tropical to subtropical, and its cyst is recorded as a fossil in upper Cenozoic sediments. Protoceratium reticulatum and Pentapl
- Published
- 2018
- Full Text
- View/download PDF
26. The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments: a summary of round table discussions
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Marine palynology and palaeoceanography, Marine Palynology, Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringué, Manuel, Dale, Barrie, De Schepper, Stijn, De Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkilä, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurélie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, André, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, Zonneveld, Karin, Marine palynology and palaeoceanography, Marine Palynology, Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringué, Manuel, Dale, Barrie, De Schepper, Stijn, De Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkilä, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurélie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, André, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, and Zonneveld, Karin
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- 2018
27. Preparing photographic plates of palynomorphs in the digital age
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Riding, James B., Head, Martin J., Riding, James B., and Head, Martin J.
- Abstract
It is essential that palynologists adequately and effectively illustrate the specimens they study. The best way to do this for formal publication is to prepare ‘plates’ (montages) of photomicrographs. This now somewhat arcane term originated as a reference to the use of copper/steel and then glass plates in pre-film photography. In order to maximise visual impact and information, plates of palynomorphs should be prepared with utmost care. If assembled so that, for example, the images are arranged neatly with consistent orientations, and depict the best preserved and most representative specimens available with minimum extraneous palynodebris, the plate will have enhanced aesthetic appeal and, crucially, the scientific significance of the association being illustrated will be greatly enhanced. Specifically, the material will be effective as an identification guide, and facilitate further interpretations. Plates today are assembled digitally; accordingly, the user must have access to suitable software, and be able to use it effectively.
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- 2018
28. Formal ratification of the subdivision of the Holocene Series/Epoch (Quaternary System/Period):two new Global Boundary Stratotype Sections and Points (GSSPs) and three new stages/subseries
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Walker, Mike, Head, Martin J., Berkelhammer, Max, Bjorck, Svante, Cheng, Hai, Cwynar, Les, Fisher, David, Gkinis, Vasilios, Long, Antony, Lowe, John, Newnhamil, Rewi, Rasmussen, Sune Olander, Weiss, Harvey, Walker, Mike, Head, Martin J., Berkelhammer, Max, Bjorck, Svante, Cheng, Hai, Cwynar, Les, Fisher, David, Gkinis, Vasilios, Long, Antony, Lowe, John, Newnhamil, Rewi, Rasmussen, Sune Olander, and Weiss, Harvey
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- 2018
29. Linking biological and geological data on dinoflagellates using the genus Spiniferites as an example:the implications of species concepts, taxonomy and dual nomenclature
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Ellegaard, Marianne, Head, Martin J., Versteegh, Gerard J. M., Ellegaard, Marianne, Head, Martin J., and Versteegh, Gerard J. M.
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- 2018
30. The dinoflagellate cyst genera Achomosphaera Evitt 1963 and Spiniferites Mantell 1850 in Pliocene to modern sediments:a summary of round table discussions
- Author
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Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringue, Manuel, Dale, Barrie, De Schepper, Stijn, de Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkila, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurelie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, Andre, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, Zonneveld, Karin, Mertens, Kenneth Neil, Van Nieuwenhove, Nicolas, Gurdebeke, Pieter R., Aydin, Hilal, Bogus, Kara, Bringue, Manuel, Dale, Barrie, De Schepper, Stijn, de Vernal, Anne, Ellegaard, Marianne, Grothe, Arjen, Gu, Haifeng, Head, Martin J., Heikkila, Maija, Limoges, Audrey, Londeix, Laurent, Louwye, Stephen, Marret, Fabienne, Masure, Edwige, Matsuoka, Kazumi, Mudie, Peta J., Penaud, Aurelie, Pospelova, Vera, Price, Andrea Michelle, Ribeiro, Sofia, Rochon, Andre, Sangiorgi, Francesca, Schreck, Michael, Torres, Vladimir, Uzar, Serdar, Versteegh, Gerard J. M., Warny, Sophie, and Zonneveld, Karin
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- 2018
31. Pentaplacodinium saltonense gen. et sp. nov. (Dinophyceae) and its relationship to the cyst-defined genus Operculodinium and yessotoxin-producing Protoceratium reticulatum
- Author
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Mertens, Kenneth Neil, Carbonell-Moore, M. Consuelo, Pospelova, Vera, Head, Martin J., Highfield, Andrea, Schroeder, Declan, Gu, Haifeng, Andree, Karl B., Fernandez, Margarita, Yamaguchi, Aika, Takano, Yoshihito, Matsuoka, Kazumi, Nézan, Elisabeth, Bilien, Gwenael, Okolodkov, Yuri, Koike, Kazuhiko, Hoppenrath, Mona, Pfaff, Maya, Pitcher, Grant, Al-Muftah, Abdulrahman, Rochon, André, Lim, Po Teen, Leaw, Chui Pin, Lim, Zhen Fei, Ellegaard, Marianne, Mertens, Kenneth Neil, Carbonell-Moore, M. Consuelo, Pospelova, Vera, Head, Martin J., Highfield, Andrea, Schroeder, Declan, Gu, Haifeng, Andree, Karl B., Fernandez, Margarita, Yamaguchi, Aika, Takano, Yoshihito, Matsuoka, Kazumi, Nézan, Elisabeth, Bilien, Gwenael, Okolodkov, Yuri, Koike, Kazuhiko, Hoppenrath, Mona, Pfaff, Maya, Pitcher, Grant, Al-Muftah, Abdulrahman, Rochon, André, Lim, Po Teen, Leaw, Chui Pin, Lim, Zhen Fei, and Ellegaard, Marianne
- Abstract
Strains of a dinoflagellate from the Salton Sea, previously identified as Protoceratium reticulatum and yessotoxin producing, have been reexamined morphologically and genetically and Pentaplacodinium saltonense n. gen. et sp. is erected to accommodate this species. Pentaplacodinium saltonense differs from Protoceratium reticulatum (Claparède et Lachmann 1859) Bütschli 1885 in the number of precingular plates (five vs. six), cingular displacement (two widths vs. one), and distinct cyst morphology. Incubation experiments (excystment and encystment) show that the resting cyst of Pentaplacodinium saltonense is morphologically most similar to the cyst-defined species Operculodinium israelianum (Rossignol, 1962) Wall (1967) and O. psilatum Wall (1967). Collections of comparative material from around the globe (including Protoceratium reticulatum and the genus Ceratocorys) and single cell PCR were used to clarify molecular phylogenies. Variable regions in the LSU (three new sequences), SSU (12 new sequences) and intergenic ITS 1–2 (14 new sequences) were obtained. These show that Pentaplacodinium saltonense and Protoceratium reticulatum form two distinct clades. Pentaplacodinium saltonense forms a monophyletic clade with several unidentified strains from Malaysia. LSU and SSU rDNA sequences of three species of Ceratocorys (C. armata, C. gourreti, C. horrida) from the Mediterranean and several other unidentified strains from Malaysia form a well-supported sister clade. The unique phylogenetic position of an unidentified strain from Hawaii is also documented and requires further examination. In addition, based on the V9 SSU topology (bootstrap values >80%), specimens from Elands Bay (South Africa), originally described as Gonyaulax grindleyi by Reinecke (1967), cluster with Protoceratium reticulatum. The known range of Pentaplacodinium saltonense is tropical to subtropical, and its cyst is recorded as a fossil in upper Cenozoic sediments. Protoceratium reticulatum and
- Published
- 2018
32. Dinoflagellate cyst paleoecology during the Pliocene–Pleistocene climatic transition in the North Atlantic
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Hennissen, Jan A. I., Head, Martin J., De Schepper, Stijn, Groeneveld, Jeroen, Hennissen, Jan A. I., Head, Martin J., De Schepper, Stijn, and Groeneveld, Jeroen
- Abstract
Dinoflagellate cysts (dinocysts) are widely used as tracers of sea surface conditions in late Quaternary marine records. However, paleoenvironmental reconstructions across the Pliocene–Pleistocene climatic transition and beyond are limited because the hydrologic conditions influencing assemblage compositions may not have a modern analogue, and the ecological optima of extinct dinocyst species are not well known. From a study of two cored sites in the central and eastern North Atlantic, we bypass these issues by statistically analyzing the variations in dinocyst assemblage composition and comparing the results directly to paleoecological parameters (δ18Obulloides, δ18Osalinity, and geochemical proxies for sea surface temperature [SST]) derived from the planktonic foraminifer Globigerina bulloides recovered from the same samples as the dinocysts. Through canonical correspondence analysis we demonstrate the co-variation of seasonality and dinocyst paleoproductivity. We show that Pyxidinopsis braboi is a cold tolerant species with an optimum SST between 12 and 14 °C. We extend the use of Nematosphaeropsis labyrinthus as an indicator of transitional climatic conditions to the Pliocene, we offer evidence for the correlation of Bitectatodinium tepikiense and Filisphaera microornata to high seasonality, and we reiterate an apparent link between Spiniferites mirabilis and eastern North Atlantic water masses. Finally, we confirm that Habibacysta tectata is cold-tolerant rather than a strictly cold-water indicator, that Operculodinium? eirikianum is a cold-intolerant species favoring outer neritic environments, and that Ataxiodinium confusum and Invertocysta lacrymosa are both warm-water species.
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- 2017
33. The Apennine foredeep (Italy) during the latest Messinian: Lago Mare reflects competing brackish and marine conditions based on calcareous nannofossils and dinoflagellate cysts
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Pellen, Romain, Popescu, Speranta-maria, Suc, Jean-pierre, Melinte-dobrinescu, Mihaela Carmen, Rubino, Jean-loup, Rabineau, Marina, Marabini, Stefano, Loget, Nicolas, Casero, Piero, Cavazza, William, Head, Martin J., Aslanian, Daniel, Pellen, Romain, Popescu, Speranta-maria, Suc, Jean-pierre, Melinte-dobrinescu, Mihaela Carmen, Rubino, Jean-loup, Rabineau, Marina, Marabini, Stefano, Loget, Nicolas, Casero, Piero, Cavazza, William, Head, Martin J., and Aslanian, Daniel
- Abstract
Sediments deposited after the peak of the Messinian Salinity Crisis (MSC) in the Apennine foredeep of Italy embody a topic debated on both chronostratigraphic and palaeoenvironmental grounds. We performed micropalaeontological (calcareous nannofossil and dinoflagellate cyst) analyses on four stratigraphic sections (Monticino, Civitella del Tronto, Fonte dei Pulcini, Fonte la Casa) and reused those previously published from Maccarone. All sections belong to the p-ev2 Fm. that includes the Colombacci deposits, usually considered emblematic of the Lago Mare in the area. Marine microfossils recorded in previous studies have often been neglected or considered reworked and hence discarded. We propose the occurrence of at least four marine inflows between 5.36 and 5.33 Ma, the first of which is reflected in the Apennine foredeep by marine dinoflagellates that are then replaced by Paratethyan (brackish) ones. Paratethyan species occupied favourable environments during intervals separating marine inflows while the marine species survived elsewhere. From this perspective, the Apennine foredeep was an isolated perched basin during most of the peak of the MSC (5.60–5.36 Ma), and was progressively and repeatedly invaded by marine waters overflowing a palaeo-sill before the beginning of the Zanclean (5.33 Ma) which itself reflects a continuing eustatic rise. The Gargano Peninsula and, offshore, the present-day Pelagosa sill may be regarded as the remnants of this Messinian sill. This interpretation provides new possibilities for ecostratigraphically correlating the sections with Lago Mare biofacies, the deposition of which unquestionably started prior to the deposition of Colombacci sediments and continued into the earliest Zanclean. The results of this study show that the Lago Mare facies cannot be restricted to a single brackish palaeoenvironment but included competing marine and brackish waters controlled by geographic and chronological factors. Deposits overlying the unconfor
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- 2017
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34. Making the case for a formal Anthropocene Epoch: an analysis of ongoing critiques
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Zalasiewicz, Jan, Waters, Colin N., Wolfe, Alexander P., Barnosky, Anthony D., Cearreta, Alejandro, Edgeworth, Matt, Ellis, Erle C., Fairchild, Ian J., Gradstein, Felix M., Grinevald, Jacques, Haff, Peter, Head, Martin J., Ivar do Sul, Juliana A., Jeandel, Catherine, Leinfelder, Reinhold, McNeill, John R., Oreskes, Naomi, Poirier, Clément, Revkin, Andrew, Richter, Daniel de B., Steffen, Will, Summerhayes, Colin, Syvitski, James P.M., Vidas, Davor, Wagreich, Michael, Wing, Scott, Williams, Mark, Zalasiewicz, Jan, Waters, Colin N., Wolfe, Alexander P., Barnosky, Anthony D., Cearreta, Alejandro, Edgeworth, Matt, Ellis, Erle C., Fairchild, Ian J., Gradstein, Felix M., Grinevald, Jacques, Haff, Peter, Head, Martin J., Ivar do Sul, Juliana A., Jeandel, Catherine, Leinfelder, Reinhold, McNeill, John R., Oreskes, Naomi, Poirier, Clément, Revkin, Andrew, Richter, Daniel de B., Steffen, Will, Summerhayes, Colin, Syvitski, James P.M., Vidas, Davor, Wagreich, Michael, Wing, Scott, and Williams, Mark
- Abstract
A range of published arguments against formalizing the Anthropocene as a geological time unit have variously suggested that it is a misleading term of non-stratigraphic origin and usage, is based on insignificant temporal and material stratigraphic content unlike that used to define older geological time units, is focused on observation of human history or speculation about the future rather than geologically significant events, and is driven more by politics than science. In response, we contend that the Anthropocene is a functional term that has firm geological grounding in a well-characterized stratigraphic record. This record, although often lithologically thin, is laterally extensive, rich in detail and already reflects substantial elapsed (and in part irreversible) change to the Earth System that is comparable to or greater in magnitude than that of previous epoch-scale transitions. The Anthropocene differs from previously defined epochs in reflecting contemporary geological change, which in turn also leads to the term's use over a wide range of social and political discourse. Nevertheless, that use remains entirely distinct from its demonstrable stratigraphic underpinning. Here we respond to the arguments opposing the geological validity and utility of the Anthropocene, and submit that a strong case may be made for the Anthropocene to be treated as a formal chronostratigraphic unit and added to the Geological Time Scale.
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- 2017
35. Dual taxonomy and nomenclature in dinoflagellate cysts: history, present status, and challenges of molecular phylogeny
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Head, Martin J., Ellegaard, Marianne, Versteegh, Gerard, Head, Martin J., Ellegaard, Marianne, and Versteegh, Gerard
- Abstract
Two separate taxonomic traditions have arisen in dinoflagellates at the generic level and below: one centred on the living motile cell but potentially incorporating all aspects of the biology, and the other based exclusively on resting cyst morphology including the fossil record. Where a cyst has been described and named as a fossil and subsequently shown through life-cycle observations to be equivalent to a named living species, the cyst morphotype may then bear two names. This dual nomenclature is supported for all algae (diatoms excepted) by the International Code of Nomenclature for Algae, Fungi and Plants (ICN) through Articles 1.2, 11.1, and 11.7 (Head, M.J. et al., 2016, Taxon 65: 902– 903). The ICN acknowledges that a fossil-taxon (having a fossil as its type) is conceptually distinct from its living (non-fossil) counterpart, and that equivalency need not mean synonymy. This distinction reflects the different species concepts involved, based on different stages of the same life cycle, and acknowledges that cyst morphology alone retrieves only limited genetic information from the fossil record. While cyst-based taxonomy strives to reflect evolution, there is a long observed mismatch between fossil-defined genera and the genera of living equivalents. Molecular phylogenies from living material now expose these discrepancies and others with new clarity. This requires the reassessment of our current taxonomic schemes if they are to be more reflective of evolution, although any major nomenclatural changes should be balanced against the value of stability in connecting living dinoflagellates to their fossil lineages.
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- 2017
36. Anthropocene: its stratigraphic basis
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Zalasiewicz, Jan, Waters, Colin, Head, Martin J., Zalasiewicz, Jan, Waters, Colin, and Head, Martin J.
- Abstract
As officers of the Anthropocene Working Group (AWG; J.Z. and C.W.) and chair of the Subcommission on Quaternary Stratigraphy (SQS; M.J.H.) of the International Commission on Stratigraphy (ICS), we note that the AWG has less power than Erle Ellis and colleagues imply (Nature 540, 192–193; 2016). Its role is merely advisory — to evaluate the Anthropocene as a formal unit in the geological timescale. Proposals must pass scrutiny by the AWG, the SQS and the ICS before being ratified by the Executive Committee of the International Union of Geological Sciences.
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- 2017
37. The Working Group on the Anthropocene: summary of evidence and interim recommendations
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Zalasiewicz, Jan, Waters, Colin N., Summerhayes, Colin P., Wolfe, Alexander P., Barnosky, Anthony D., Cearreta, Alejandro, Crutzen, Paul, Ellis, Erle, Fairchild, Ian J., Gałuszka, Agnieszka, Haff, Peter, Hajdas, Irka, Head, Martin J., Ivar do Sul, Juliana A., Jeandel, Catherine, Leinfelder, Reinhold, McNeill, John R., Neal, Cath, Odada, Eric, Oreskes, Naomi, Steffen, Will, Syvitski, James, Vidas, Davor, Wagreich, Michael, Williams, Mark, Zalasiewicz, Jan, Waters, Colin N., Summerhayes, Colin P., Wolfe, Alexander P., Barnosky, Anthony D., Cearreta, Alejandro, Crutzen, Paul, Ellis, Erle, Fairchild, Ian J., Gałuszka, Agnieszka, Haff, Peter, Hajdas, Irka, Head, Martin J., Ivar do Sul, Juliana A., Jeandel, Catherine, Leinfelder, Reinhold, McNeill, John R., Neal, Cath, Odada, Eric, Oreskes, Naomi, Steffen, Will, Syvitski, James, Vidas, Davor, Wagreich, Michael, and Williams, Mark
- Abstract
Since 2009, the Working Group on the ‘Anthropocene’ (or, commonly, AWG for Anthropocene Working Group), has been critically analysing the case for formalization of this proposed but still informal geological time unit. The study to date has mainly involved establishing the overall nature of the Anthropocene as a potential chronostratigraphic/geochronologic unit, and exploring the stratigraphic proxies, including several that are novel in geology, that might be applied to its characterization and definition. A preliminary summary of evidence and interim recommendations was presented by the Working Group at the 35th International Geological Congress in Cape Town, South Africa, in August 2016, together with results of voting by members of the AWG indicating the current balance of opinion on major questions surrounding the Anthropocene. The majority opinion within the AWG holds the Anthropocene to be stratigraphically real, and recommends formalization at epoch/series rank based on a mid-20th century boundary. Work is proceeding towards a formal proposal based upon selection of an appropriate Global boundary Stratotype Section and Point (GSSP), as well as auxiliary stratotypes. Among the array of proxies that might be used as a primary marker, anthropogenic radionuclides associated with nuclear arms testing are the most promising; potential secondary markers include plastic, carbon isotope patterns and industrial fly ash. All these proxies have excellent global or near-global correlation potential in a wide variety of sedimentary bodies, both marine and non-marine.
- Published
- 2017
38. (087–090) Proposal to treat the use of a hyphen in the name of a fossil-genus as an orthographical error
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Anderson, Heidi, David J. Batten, David, Cantrill, David, Cleal, Christopher, Susanne Feist-Burkhardt, Susanne, Fensome, Robert, Head, Martin, Herendeen, Patrick, Jaramillo, Carlos, Kvaček, Jiří, McLoughlin, Stephen, Skog, Judith, Takahashi, Masamichi, Wicander, Reed, Anderson, Heidi, David J. Batten, David, Cantrill, David, Cleal, Christopher, Susanne Feist-Burkhardt, Susanne, Fensome, Robert, Head, Martin, Herendeen, Patrick, Jaramillo, Carlos, Kvaček, Jiří, McLoughlin, Stephen, Skog, Judith, Takahashi, Masamichi, and Wicander, Reed
- Abstract
We propose modifications to the Code such that use of a hyphen in the name of a fossil-genus is treated as an error to be corrected by deletion of the hyphen. This will circumvent the need to conserve the numerous de-hyphenated names against unused hyphenated forms. We propose changes to Art. 60 of the Code to allow this correction, and the addition of a phrase in Art. 20 to add clarity to the naming of fossil-genera., Exceptional permineralized biotas - windows into the evolution and functional diversity of terrestrial ecosystems through time
- Published
- 2015
- Full Text
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39. An optimized scheme of lettered marine isotope substages for the last 1.0 million years, and the climatostratigraphic nature of isotope stages and substages
- Author
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Railsback, L. Bruce, Gibbard, Philip L., Head, Martin J., Voarintsoa, Ny Riavo G., Toucanne, Samuel, Railsback, L. Bruce, Gibbard, Philip L., Head, Martin J., Voarintsoa, Ny Riavo G., and Toucanne, Samuel
- Abstract
A complete and optimized scheme of lettered marine isotope substages spanning the last 1.0 million years is proposed. Lettered substages for Marine Isotope Stage (MIS) 5 were explicitly defined by Shackleton (1969), but analogous substages before or after MIS 5 have not been coherently defined. Short-term discrete events in the isotopic record were defined in the 1980s and given decimal-style numbers, rather than letters, but unlike substages they were neither intended nor suited to identify contiguous intervals of time. Substages for time outside MIS 5 have been lettered, or in some cases numbered, piecemeal and with conflicting designations. We therefore propose a system of lettered substages that is complete, without missing substages, and optimized to match previous published usage to the maximum extent possible. Our goal is to provide order and unity to a taxonomy and nomenclature that has developed ad hoc and somewhat chaotically over the decades. Our system is defined relative to the LR04 stack of marine benthic oxygen isotope records, and thus it is grounded in a continuous record responsive largely to changes in ice volume that are inherently global. This system is intended specifically for marine oxygen isotope stages, but it has relevance also for oxygen isotope stages recognized in time-series of non-marine oxygen isotope data, and more generally for climatic stages, which are recognized in time-series of non-isotopic as well as isotopic data. The terms “stage” and “substage” in this context are best considered to represent climatostratigraphic units, and thus “climatic stages” and “climatic substages”, because they are recognized from geochemical and sedimentary responses to climate change that may not have been synchronous at global scale.
- Published
- 2015
- Full Text
- View/download PDF
40. Statistically assessing the correlation between salinity and morphology in cysts produced by the dinoflagellate Protoceratium reticulatum from surface sediments of the North Atlantic Ocean, Mediterranean–Marmara–Black Sea region, and Baltic–Kattegat–Skagerrak estuarine system
- Author
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Jansson, Ida-Maria, Mertens, Kenneth Neil, Head, Martin J., de Vernal, Anne, Londeix, Laurent, Marret, Fabienne, Matthiessen, Jens, Sangiorgi, Francesca, Jansson, Ida-Maria, Mertens, Kenneth Neil, Head, Martin J., de Vernal, Anne, Londeix, Laurent, Marret, Fabienne, Matthiessen, Jens, and Sangiorgi, Francesca
- Published
- 2014
41. Palynological evidence for a southward shift of the North Atlantic Current at ~2.6 Ma during the intensification of late Cenozoic Northern Hemisphere glaciation
- Author
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Hennissen, Jan A.I., Head, Martin J., De Schepper, Stijn, Groeneveld, Jeroen, Hennissen, Jan A.I., Head, Martin J., De Schepper, Stijn, and Groeneveld, Jeroen
- Abstract
The position of the North Atlantic Current (NAC) during the intensification of Northern Hemisphere glaciation (iNHG) has been evaluated using dinoflagellate cyst assemblages and foraminiferal geochemistry from a ~260 kyr interval straddling the base of the Quaternary System from two sites: eastern North Atlantic Deep Sea Drilling Project Site 610 in the path of the present NAC and central North Atlantic Integrated Ocean Drilling Program Site U1313 in the subtropical gyre. Stable isotope and foraminiferal Mg/Ca analyses confirm cooling near the marine isotope stage (MIS) G7–G6 transition (2.74 Ma). However, a continued dominance of the dinoflagellate cyst Operculodinium centrocarpum sensu Wall and Dale (1966) indicates an active NAC in the eastern North Atlantic for a further 140 kyr. At MIS 104 (~2.60 Ma), a profound dinoflagellate cyst assemblage turnover indicates NAC shutdown in the eastern North Atlantic, implying elevated atmospheric pressure over the Arctic and a resulting shift in the westerlies that would have driven the NAC. These findings challenge recent suggestions that there was no significant southward shift of the NAC or the Arctic Front during iNHG, and reveal a fundamental climatic reorganization near the base of the Quaternary.
- Published
- 2014
42. Public participation in soil surveys : lessons from a pilot study in England
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Bone, James, Archer, Michael, Barraclough, Declan, Eggleton, Paul, Flight, Dee, Head, Martin, Jones, David T., Scheib, Catherine, Voulvoulis, Nikolaos, Bone, James, Archer, Michael, Barraclough, Declan, Eggleton, Paul, Flight, Dee, Head, Martin, Jones, David T., Scheib, Catherine, and Voulvoulis, Nikolaos
- Abstract
In many countries there are policies in place that impact on soils, but very few legislative or policy tools specifically for the protection of soil. Recent EU legislative proposals on soil protection have been met with opposition on the grounds of excessive cost and resource demands. With the need for evidence based policy, and recognition that involving the public in environmental monitoring is an effective way of increasing understanding and commitment, there has been growing interest in soil surveys. In addition, it is accepted that the success of environmental policies depends greatly on how effectively scientists, regulators, stakeholders, and society communicate. This paper presents the Open Air Laboratories (OPAL) Soil and Earthworm Survey as an example of public participation in soil surveys that aims to integrate the above. It is demonstrated how such surveys generate data that can be used to prioritise soil assessment, in order to address some of the concerns and objections to soil protection policies. Lessons from this pilot study in England highlight that with strategic planning of civic participation activities, this approach can deliver improvements in the quality of the evidence collected and allow for effective public involvement in policymaking and implementation, on top of direct educational benefits.
- Published
- 2012
43. Formal ratification of the GSSP for the base of the Calabrian Stage (second stage of the Pleistocene Series, Quaternary System)
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Cita, Maria Bianca, Gibbard, Phillip, Head, Martin J., Alloway, B., Beu, A., Coltorti, M., Hall, V.M., Jiaqi, Liu, Knudsen , K.L., van Kolfschoten, T., Pillans, Bradley, Cita, Maria Bianca, Gibbard, Phillip, Head, Martin J., Alloway, B., Beu, A., Coltorti, M., Hall, V.M., Jiaqi, Liu, Knudsen , K.L., van Kolfschoten, T., and Pillans, Bradley
- Abstract
The Calabrian Stage is now formally defined by the Global Boundary Stratotype Section and Point (GSSP) at Vrica, Calabria, Italy. This GSSP had previously defined the base of the Pleistocene Series. The Calabrian becomes the second stage of the Pleistocene Series and Quaternary System, following the Gelasian. The GSSP occurs at the base of the marine clay stone conformably overlying sapropelic bed 'e' within Segment B in the Vrica section. This lithological level represents the primary marker for the recognition of the boundary, and is assigned an astronomical age of 1.80 Ma on the basis of sapropel calibration. It coincides with the transition from Marine Isotope Stage 65 to 64, and the underlying sapropel bed 'e' is assigned to the Mediterranean Precession-Related Sapropel layer 176. Secondary markers include calcareous plankton bioevents of widely distributed taxa. The boundary falls between the highest occurrence o/Discoaster brouweri (below) and the lowest common occurrence of left-coiling Neogloboquadrina pachyderma (above), and below the lowest occurrences of medium-sized Gephyrocapsa (including G oceanica) and Globigerinoides tenellus. The top of the Olduvai Subchron is identified c.8m above the GSSP. Ratification of the Calabrian Stage effectively completes the Lower Pleistocene Subseries.
- Published
- 2012
44. From chemical risk assessment to environmental quality management : the challenge for soil protection
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Bone, James, Head, Martin, Jones, David T., Barraclough, Declan, Archer, Michael, Scheib, Catherine, Flight, Dee, Eggleton, Paul, Voulvoulis, Nikolaos, Bone, James, Head, Martin, Jones, David T., Barraclough, Declan, Archer, Michael, Scheib, Catherine, Flight, Dee, Eggleton, Paul, and Voulvoulis, Nikolaos
- Abstract
The 40 years that have passed since the beginning of the ‘environmental revolution’ has seen a large increase in development of policies for the protection of environmental media and a recognition by the public of the importance of environmental quality. There has been a shift from policy in reaction to high profile events, then to control of releases to single environmental media, and to the present position of moving toward integrated management of all environmental media at present. This development has moved away from classical chemical risk assessment toward environmental holism, including recognition of the ecological value of these media. This work details how policy developments have taken place for air and water, with examples from the USA and EU, in order to compare this with policy development regarding soil. Soil, with quite different policy frameworks and distinct uses, understanding, and threats compared to other environmental media, is currently attracting attention regarding the need for its protection independent of use. Challenges for soil policy are identified and evaluated, and recommendations on how these challenges can be overcome are discussed with relevance to water and air protection policy.
- Published
- 2011
45. Soil quality assessment under emerging regulatory requirements
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Bone, James, Head, Martin, Barraclough, Declan, Archer, Michael, Scheib, Catherine, Flight, Dee, Voulvoulis, Nikolaos, Bone, James, Head, Martin, Barraclough, Declan, Archer, Michael, Scheib, Catherine, Flight, Dee, and Voulvoulis, Nikolaos
- Abstract
New and emerging policies that aim to set standards for protection and sustainable use of soil are likely to require identification of geographical risk/priority areas. Soil degradation can be seen as the change or disturbance in soil quality and it is therefore crucial that soil and soil quality are well understood to protect soils and to meet legislative requirements. To increase this understanding a review of the soil quality definition evaluated its development, with a formal scientific approach to assessment beginning in the 1970s, followed by a period of discussion and refinement. A number of reservations about soil quality assessment expressed in the literature are summarised. Taking concerns into account, a definition of soil quality incorporating soil's ability to meet multifunctional requirements, to provide ecosystem services, and the potential for soils to affect other environmental media is described. Assessment using this definition requires a large number of soil function dependent indicators that can be expensive, laborious, prone to error, and problematic in comparison. Findings demonstrate the need for a method that is not function dependent, but uses a number of cross-functional indicators instead. This method to systematically prioritise areas where detailed investigation is required, using a ranking based against a desired level of action, could be relatively quick, easy and cost effective. As such this has potential to fill in gaps and compliment existing monitoring programs and assist in development and implementation of current and future soil protection legislation.
- Published
- 2010
46. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.588 Ma
- Author
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Gibbard, Phillip, Head, Martin J., Walker, Michael J.C., Alloway, B., Beu, A., Coltorti, M., Hall, V.M., Jiaqi, Liu, Knudsen , K.L., van Kolfschoten, T., Pillans, Bradley, Gibbard, Phillip, Head, Martin J., Walker, Michael J.C., Alloway, B., Beu, A., Coltorti, M., Hall, V.M., Jiaqi, Liu, Knudsen , K.L., van Kolfschoten, T., and Pillans, Bradley
- Abstract
In June 2009, the Executive Committee of the International Union of Geological Sciences (IUGS) formally ratified a proposal by the International Commission on Stratigraphy to lower the base of the Quaternary System/Period to the Global Stratotype Section
- Published
- 2010
47. Reducing the Computational Complexity of Electron Correlation Techniques: Final Phase I SBIR Report to AFOSR
- Author
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Q-CHEM INC PITTSBURGH PA, Johnson, Benny G., Head, Martin P., Q-CHEM INC PITTSBURGH PA, Johnson, Benny G., and Head, Martin P.
- Abstract
Quantitative prediction of the structure, properties, and chemical reactivity of molecules by computer programs using first principles electronic structure methods is a valuable complement to experimental studies, because the latter are often difficult or impossible for transient reactive species. Unfortunately, the electronic structure methods which achieve quantitative chemical accuracy, such as those based on coupled cluster theory, are currently limited in applicability to small molecules of less than about ten first row atoms. This is because of the unphysical increase in computational cost with molecular size in standard implementations. This Phase I SBIR research has developed a new from the ground up approach to reformulating these proven electron correlation methods in terms of atom centered spatially localized quantities. The feasibility and formal advantages of the new formulation has been demonstrated in preliminary work based on the simplest electron correlation method, second order perturbation theory. Trial calculations on medium sized molecules indicated that recovery of both absolute electron correlation energy, and also recovery of relative energies across potential surfaces is excellent. The results have shown the potential of these new local correlation methods to allow the study of much larger molecules than can be treated conventionally, with roughly an order of magnitude improvement being possible.
- Published
- 1997
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