0000000000235293

AUTHOR

Melanie J. Leng

0000-0003-1115-5166

showing 11 related works from this author

Sclerochronological evidence of pronounced seasonality from the late Pliocene of the southern North Sea basin and its implications

2022

Oxygen isotope (δ18O) sclerochronology of benthic marine molluscs provides a means of reconstructing the seasonal range in seafloor temperature, subject to use of an appropriate equation relating shell δ18O to temperature and water δ18O, a reasonably accurate estimation of water δ18O, and due consideration of growth-rate effects. Taking these factors into account, δ18O data from late Pliocene bivalves of the southern North Sea basin (Belgium and the Netherlands) indicate a seasonal seafloor range a little smaller than now in the area. Microgrowth-increment data from Aequipecten opercularis, together with the species composition of the bivalve assemblage and aspects of preservation, suggest …

Global and Planetary Changebiologyδ18OStratigraphyStratification (water)PaleontologySeasonalitymedicine.diseasebiology.organism_classificationSeafloor spreadingAequipectenOceanographySclerochronologymedicineTemperate climateThermoclineGeologyClimate of the Past
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The Valanginian positive carbon isotope event in Arctic Russia: Evidence from terrestrial and marine isotope records and implications for global carb…

2010

The data presented here comprise Ryazanian–Valanginian carbon isotope ratios analyzed from fossil wood and belemnites from the shallow marine Boyarka River succession in Siberia. Additional belemnite carbon isotope ratios from the Izhma River succession (also Ryazanian–Valanginian) in Russia are also presented. The wood-derived and belemnite-derived isotope ratios are considered to primarily reflect changes in the terrestrial and marine carbon isotope reservoirs respectively. The δ13Ccarb and δ13Cwood records reveal a distinct mid-Valanginian positive carbon isotope excursion, with the initiation occurring near the Boreal Russian michalskii–polyptychus zone boundary, which is broadly time-e…

Total organic carbonbiologyPaleontologychemistry.chemical_elementbiology.organism_classificationCretaceousCarbon cyclePaleontologychemistry.chemical_compoundArcticchemistryIsotopes of carbonCarbonateBelemnitesCarbonGeologyCretaceous Research
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Isotopic signals from Callovian–Kimmeridgian (Middle–Upper Jurassic) belemnites and bulk organic carbon, Staffin Bay, Isle of Skye, Scotland

2009

Abstract: The stable isotope data presented here significantly extend and expand upon previous isotopic investigations of the Middle to Late Jurassic interval. The belemnite samples collected from the Staffin Bay and Staffin Shale formations from the Isle of Skye, Scotland, yielded oxygen isotope values consistent with Callovian–Kimmeridgian palaeotemperatures of 6.7–20.6 °C. The carbon isotope data comprise one of the first moderately high-resolution investigations of the relationship between terrestrial δ 13 C org (predominantly fossil wood debris) and marine δ 13 C carb (belemnites) as derived from a geologically coeval record. The Staffin Bay data reveal a broad Early to Mid-Oxfordian p…

Total organic carbonPaleontologybiologyIsotopes of carbonStable isotope ratioPhanerozoicFossil woodGeologybiology.organism_classificationBelemnitesBayGeologyIsotopes of oxygenJournal of the Geological Society
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ISOTOPIC TEMPERATURES FROM THE EARLY AND MID-PLIOCENE OF THE US MIDDLE ATLANTIC COASTAL PLAIN, AND THEIR IMPLICATIONS FOR THE CAUSE OF REGIONAL MARIN…

2017

Mean seasonal extreme temperatures on the seafloor calculated from the shell d 18 Oofthescallop Placopecten clintonius from the basal part of the early Pliocene Sunken Meadow Member (Yorktown Formation) in Virginia are very similar to those from the same horizon at the latitude of Cape Hatteras in North Carolina ( ~ 210 km to the south). The lowest and highest temperatures calculated from each shell (using d 18 O seawater ¼þ 0.7 % )givemean values for winter and summer of 8.4 6 1.1 8 C( 6 1 r ) and 18.2 6 0.6 8 CinVirginia,and8.6 6 0.4 8 Cand16.5 6 1.1 8 C in North Carolina (respective median temperatures: 13.3 8 C and 12.6 8 C). Patterns of ontogenetic variation in d 18 O, d 13 C and micro…

010506 paleontologygeographygeography.geographical_feature_categoryδ13CYorktown Formationδ18OCoastal plainPaleontologyOceanic climate010502 geochemistry & geophysics01 natural sciencesGulf StreamOceanographySclerochronologyPaleoclimatologyEcology Evolution Behavior and SystematicsGeology0105 earth and related environmental sciences
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The stable isotope composition of organic and inorganic fossils in lake sediment records: current understanding, challenges, and future directions

2018

This paper provides an overview of stable isotope analysis (H, C, N, O, Si) of the macro- and microscopic remains from aquatic organisms found in lake sediment records and their application in (palaeo)environmental science. Aquatic organisms, including diatoms, macrophytes, invertebrates, and fish, can produce sufficiently robust remains that preserve well as fossils and can be identified in lake sediment records. Stable isotope analyses of these remains can then provide valuable insights into habitat-specific biogeochemistry, feeding ecology, but also on climatic and hydrological changes in and around lakes. Since these analyses focus on the remains of known and identified organisms, they …

010506 paleontologyArcheologyTaphonomy010504 meteorology & atmospheric sciencesorganic remainsstable isotopessedimentit580 Plants (Botany)01 natural sciencesInorganic remainsäyriäisetIsotope fractionationpiilevätEcology Evolution Behavior and Systematics0105 earth and related environmental sciencesIsotope analysisStable isotopesDiatomsGlobal and Planetary Changeinorganic remainsisotoopitEcologyStable isotope ratioLake ecosystemBiogeochemistryOstracodsGeologyselkärangattomatInvertebratespaleolimnologiaMacrophytelake sedimentLake sedimentostracodsOrganic remainsPaleoecologyEnvironmental science
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Late Pleistocene-Holocene coastal adaptation in central Mediterranean: Snapshots from Grotta d’Oriente (NW Sicily)

2018

Marine faunal remains from Grotta d’Oriente (Favignana Island, NW Sicily) offer invaluable snapshots of human-coastal environment interaction in the central Mediterranean from the Late Pleistocene to the Middle Holocene. The long-term shellfish and fish records reflect human exploitation of coastal environments undergoing considerable reorganizations during the postglacial sea level rise and the progressive isolation of Favignana from mainland Sicily. We detected an intensification of marine resource exploitation between ∼9.6 ka and ∼7.8 ka BP, which corresponds with the isolation of Favignana Island and, later on, with the introduction of early agro-pastoral economy in this region. We sugg…

Mediterranean climate010506 paleontology060102 archaeologyPleistoceneNW SicilyCentral Mediterranean NW Sicily Upper Palaeolithic to Early Neolithic Coastal adaptation Environmental changeUpper Palaeolithic to Early Neolithic06 humanities and the artsSettore GEO/01 - Paleontologia E PaleoecologiaEnvironmental change01 natural sciencesCentral MediterraneanOceanographyGeographySea level riseCoastal adaptation0601 history and archaeologyMainlandAdaptationMarine productivityExploitation of natural resourcesHolocene0105 earth and related environmental sciencesEarth-Surface ProcessesQuaternary International
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Life history, environment and extinction of the Scallop Carolinapecten Eboreus (Conrad) in the Plio-Pleistocene of the U.S. Eastern Seaboard

2019

Plio-Pleistocene mass extinction of marine bivalves on the U.S. eastern seaboard has been attributed to declines in temperature and primary production. We investigate the relationship of growth rate in the scallop Carolinapecten eboreus to variation in these parameters to determine which contributed to its extinction. We use ontogenetic profiles of shell δ18O to estimate growth rate and seasonal temperature, microgrowth-increment data to validate δ18O-based figures for growth rate, and shell δ13C to supplement assemblage evidence of production. Postlarval growth started in the spring/summer in individuals from the Middle Atlantic Coastal Plain but in the autumn/ winter in some from the Gulf…

Extinction event010506 paleontologygeographygeography.geographical_feature_categoryExtinctionδ13CCoastal plainEcologyPaleontologyPlio-PleistoceneBiology010502 geochemistry & geophysics01 natural sciencesPredationScallopGrowth rateEcology Evolution Behavior and Systematics0105 earth and related environmental sciences
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Sea ice extent and seasonality for the Early Pliocene northern Weddell Sea

2010

Abstract Growth increment analysis coupled with stable isotopic data ( δ 18 O/ δ 13 C) from Early Pliocene (ca 4.7 Ma) Austrochlamys anderssoni from shallow marine sediments of the Cockburn Island Formation, northern Antarctic Peninsula, suggest these bivalves grew through much of the year, even during the coldest parts of winter recorded in the shells. The high frequency fluctuation in growth increment width of A. anderssoni appears to reflect periodic, but year-round, agitation of the water column enhancing benthic food supply from organic detritus. This suggests that Austrochlamys favoured waters that were largely sea ice free. Our data support interpretation of the Cockburn Island Forma…

Drift iceWeddell Sea Bottom Watergeographygeography.geographical_feature_category010504 meteorology & atmospheric sciencesPaleontologyAntarctic sea ice010502 geochemistry & geophysicsOceanography01 natural sciencesArctic ice packOceanographyInterglacialSea iceCryosphere14. Life underwaterIce sheetEcology Evolution Behavior and SystematicsGeology0105 earth and related environmental sciencesEarth-Surface Processes
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Growth-increment characteristics and isotopic (delta O-18) temperature record of sub- thermocline Aequipecten opercularis (Mollusca: Bivalvia): evide…

2021

Abstract The shell δ18O of young modern Aequipecten opercularis from the southern North Sea provides an essentially faithful record of seasonal variation in seafloor temperature. In this well-mixed setting, A. opercularis shell δ18O also serves as a proxy for seasonal variation in surface temperature. Individuals from less agitated (e.g. deeper) settings in a warm climate would not be expected to record the full seasonal range in surface temperature because of thermal stratification in summer. Such circumstances have been invoked to explain cool isotopic summer temperatures from early Pliocene A. opercularis of eastern England. Support for a sub-thermocline setting derives from high-amplitu…

010506 paleontologybiologyδ18OPaleontologyOceanic climateSeasonality010502 geochemistry & geophysicsOceanographybiology.organism_classificationmedicine.disease01 natural sciencesAequipectenOceanographyMediterranean seaBivalve ; Hydrography ; Marine climate ; Pliocene ; SclerochronologySclerochronologymedicineThermoclineEcology Evolution Behavior and SystematicsGeology0105 earth and related environmental sciencesEarth-Surface ProcessesTemperature record
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Marine climate and hydrography of the Coralline Crag (early Pliocene, UK): isotopic evidence from 16 benthic invertebrate taxa

2019

The taxonomic composition of the biota of the Coralline Crag Formation (early Pliocene, eastern England) provides conflicting evidence of seawater temperature during deposition, some taxa indicating cool temperate conditions by analogy with modern representatives or relatives, others warm temperate to subtropical/tropical conditions. Previous isotopic (δ18O) evidence of seasonal seafloor temperatures from serial ontogenetic sampling of bivalve mollusk shells indicated cool temperate winter (<10 °C) and/or summer (<20 °C) conditions but was limited to nine profiles from two species, one ranging into and one occurring exclusively in cool temperate settings at present. We supplement these resu…

010504 meteorology & atmospheric sciencesRange (biology)sub-01sub-04Oceanic climateGeologyBiotaSubtropics010502 geochemistry & geophysics01 natural sciencesSeafloor spreadingOceanographyGeochemistry and PetrologyBenthic zoneTemperate climateGeology0105 earth and related environmental sciencesInvertebrate
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Isotopic signals from Callovian–Kimmeridgian (Middle–Upper Jurassic) belemnites and bulk organic carbon, Staffin Bay, Isle of Skye, Scotland

2016

The stable isotope data presented here significantly extend and expand upon previous isotopic investigations of the Middle to Late Jurassic interval. The belemnite samples collected from the Staffin Bay and Staffin Shale formations from the Isle of Skye, Scotland, yielded oxygen isotope values consistent with Callovian–Kimmeridgian palaeotemperatures of 6.7–20.6 °C. The carbon isotope data comprise one of the first moderately high-resolution investigations of the relationship between terrestrial δ13Corg (predominantly fossil wood debris) and marine δ13Ccarb (belemnites) as derived from a geologically coeval record. The Staffin Bay data reveal a broad Early to Mid-Oxfordian positive carbon i…

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