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K T Pickering - One of the best experts on this subject based on the ideXlab platform.

  • Trace Fossils as diagnostic indicators of deep-marine environments, Middle Eocene Ainsa-Jaca basin, Spanish Pyrenees
    SEDIMENTOLOGY, 2008
    Co-Authors: K T Pickering
    Abstract:

    A quantitative study of trace Fossil abundance in the Middle Eocene deep-marine clastic systems, Ainsa-Jaca basin, Spanish Pyrenees, shows that they are powerful discriminators of submarine fan and related environments. Sixteen fan and related environments are recognized from upper-slope gully to the distal basin-floor. For each environment, the degree of bioturbation (density), trace-Fossil diversity, number of pre-depositional and post-depositional trace Fossils, as well as the number of graphoglyptid ichnospecies were quantified. In the more laterally confined and channel-dominated Ainsa basin, there is a trend of increasing bioturbation intensity and trace-Fossil diversity away from channel-axis to off-axis environments. In the more unconfined and distal Jaca basin, there is a trend of increasing trace-Fossil diversity and number of pre-depositional trace Fossils including graphoglyptids from the channel-lobe transition to the fan-fringe. The trace-Fossil Assemblages of the Ainsa-Jaca basin are characteristic of a number of sub-ichnofacies of the Nereites ichnofacies. In the distal Jaca basin, the Paleodictyon sub-ichnofacies occurs in the lobe-fringe and fan-fringe, whereas the distal basin-floor has a trace-Fossil Assemblage typical of the Paleodictyon sub-ichnofacies, but with a high proportion of post-depositional fodinichnia. Trace-Fossil Assemblages of proximal basin, axial, environments are characteristic of the Ophiomorpha rudis sub-ichnofacies, whilst proximal off-axis environments, have a mixed Paleodictyon-Ophiomorpha rudis sub-ichnofacies trace-Fossil Assemblage.

Alec Schassburger - One of the best experts on this subject based on the ideXlab platform.

  • a diverse deep sea trace Fossil Assemblage from the adriatic flysch formation middle eocene middle miocene montenegro central mediterranean
    Palaeogeography Palaeoclimatology Palaeoecology, 2018
    Co-Authors: Zoran Kilibarda, Alec Schassburger
    Abstract:

    Abstract Our study of ichnoFossils in the Adriatic Flysch suggests that mid-fan environments, with 30 ichnospecies and 13 architectural designs, provided most productive and best preservation conditions in the fine-grained turbidite system of the Dinarides-Albanides-Helenides deep foreland basin. The Adriatic Flysch Formation at its type section in Crnjak Cove (Montenegro) represents a 300-m-thick turbidite succession deposited from the middle Eocene to the middle Miocene. The flysch is exposed in an asymmetrical syncline in a 750-m-long outcrop. The conglomerates, sandstones, and mudstones are arranged in seven distinct turbidite facies, which represent three superimposed submarine fans. The inner-, mid-, and outer-fan facies of the submarine fans contain sixteen ichnogenera and thirty three ichnospecies, which exhibit thirteen architectural designs. The inner fan conglomerates and coarse-grained sandstones contain a low diversity (Ophiomorpha rudis, Ophiomorpha annulata, and Halopoa imbricata), a low disparity (two architectural designs), and a low-density post-depositional trace Fossil Assemblages of the Ophiomorpha rudis ichnosubfacies of the Nereites ichnofacies. The mid-fan greywackes contain very diverse pre-depositional trace Fossils (Belorhaphe zickzack, ?Cosmorhaphe isp., Desmograpton dertonensis, Gordia isp., Helminthopsis isp., Helminthorhaphe flexuosa, ?Megagrapton isp., Paleodictyon arvense, Paleodictyon hexagonum, Paleodictyon itallicum, Paleodictyon latum, Paleodictyon majus, Paleodictyon maximum, Paleodictyon strozzii, Paleodictyon isp., Scolicia strozzii, Squamodictyon isp.) having six architectural designs and abundant post-depositional trace Fossils (Halopoa imbricata, Ophiomorpha annulata, Ophiomorpha nodosa, Ophiomorpha rudis, Planolites beverleyensis, Planolites montanus, Palaeophycus alternatus, Palaeophycus striatus, Palaeophycus tubularis, Rhizocorallium commune, Scolicia prisca, Scolicia strozzii, Zoophycos isp.) exhibiting seven architectural designs, which constitute the Paleodictyon-Ophiomorpha rudis ichnosubfacies of the Nereites icnhnofacies in the Adriatic Flysch. The waning turbidity currents with slower rates of sediment deposition and deficiency of nutrients favored grapholyptid colonization of the outer fans. Relatively low abundance, and great diversity of graphoglyptids (Helminthorhaphe flexuosa, Desmograpton dertonensis, ?Megagrapton isp., Paleodictyon arvense, Paleodictyon hexagonum, Paleodictyon majus, Paleodictyon minimum, Paleodictyon strozzii, Paleodictyon isp., Squamodictyon isp.), but low disparity (three architectural designs), represents the Paleodictyon ichnosubfacies of the Nereites ichnofacies in the outer fan facies of the Adriatic Flysch. The diversity of pre-depositional ichnoFossils in the Adriatic Flysch exceeds post-depositional forms, reflecting a dominance of K-selected over r-selected population strategies in a stable oligotrophic environment.

Michael C Pante - One of the best experts on this subject based on the ideXlab platform.

  • the carnivorous feeding behavior of early homo at hwk ee bed ii olduvai gorge tanzania
    Journal of Human Evolution, 2017
    Co-Authors: Michael C Pante, Jackson K. Njau, Carmen Martinramos, Blaire Hensleymarschand, Trevor L Keevil, R Peters, Ignacio Torre
    Abstract:

    The regular consumption of large mammal carcasses, as evidenced by butchery marks on Fossils recovered from Early Stone Age archaeological sites, roughly coincides with the appearance of Homo habilis. However, the significance of this niche expansion cannot be appreciated without an understanding of hominin feeding behavior and their ecological interactions with mammalian carnivores. The Olduvai Geochronology and Archaeology Project (OGAP) has recovered a large and well-preserved Fossil Assemblage from the HWK EE site, which was deposited just prior to the first appearance of Acheulean technology at Olduvai Gorge and likely represents one of the last H. habilis sites at Olduvai. This taphonomic analysis of the larger mammal Fossil Assemblage excavated from HWK EE shows evidence of multiple occupations over a long period of time, suggesting the site offered resources that were attractive to hominins. There was a water source indicated by the presence of fish, crocodiles, and hippos, and there was possible tree cover in an otherwise open habitat. The site preserves several stratigraphic intervals with large Fossil and artifact Assemblages within two of these intervals. Feeding traces on bone surfaces suggest hominins at the site obtained substantial amounts of flesh and marrow, particularly from smaller size group 1-2 carcasses, and exploited a wide range of taxa, including megafauna. A strong carnivore signal suggests hominins scavenged much of their animal foods during the two main stratigraphic intervals. In the later interval, lower carnivore tooth mark and hammerstone percussion mark frequencies, in addition to high epiphyseal to shaft fragment ratios, suggest hominins and carnivores did not fully exploit bone marrow and grease, which may have been acquired from nutritionally-stressed animals that died during a dry period at Olduvai. The diversity of fauna that preserve evidence of butchery suggests that the HWK EE hominins were opportunistic in their acquisition of carcass foods.

  • the larger mammal Fossil Assemblage from jk2 bed iii olduvai gorge tanzania implications for the feeding behavior of homo erectus
    Journal of Human Evolution, 2013
    Co-Authors: Michael C Pante
    Abstract:

    Abstract Little is known about the type and amount of animal proteins consumed by Homo erectus, a species distinguished from its predecessors by more human-like brain and body proportions and its association with more advanced stone tool technology. Here I present an interpretation of the feeding behavior of African H. erectus based upon the first taphonomic analysis of the larger mammal Fossil Assemblage from the JK2 site, Bed III, Olduvai Gorge. Results indicate that both hominins and carnivores consumed some flesh and bone marrow at the site. A low incidence of percussion marking suggests hominins did not break all long bones in the Assemblage. Relatively high carnivore tooth mark frequencies and low cut mark frequencies independently suggest that both hominins and carnivores had access to flesh, while specimens that are both tooth- and butchery-marked demonstrate occasional hominin and carnivore feeding from the same carcass. Together, the bone surface modification data suggest a mixed and possibly time-averaged taphonomic history for the Assemblage with at least some carcasses accessed by hominins early in the consumption sequence and others only by carnivores. The results for the JK2 Assemblage contribute to a growing literature concerning the feeding behavior of African H. erectus, a species that appears to have relied on carcass foods to meet some of the nutritional demands of its larger brain and body size.

Alfred Uchman - One of the best experts on this subject based on the ideXlab platform.

  • ichnological analysis of the bidart and sopelana cretaceous paleogene k pg boundary sections basque basin w pyrenees refining eco sedimentary environment
    Sedimentary Geology, 2011
    Co-Authors: Francisco J Rodrigueztovar, Alfred Uchman, Xabier Orueetxebarria, Estibaliz Apellaniz, Juan Ignacio Baceta
    Abstract:

    Abstract Ichnological analysis of two Cretaceous–Paleogene boundary sections at Bidart (SE France) and Sopelana (N Spain) has been conducted in order to refining eco-sedimentary environment, and to a make comparison with previous interpretations based on microFossils. In both sections, trace Fossil Assemblage is low diverse, consisting of Chondrites, Planolites, Thalassinoides, Trichichnus, Zoophycos, and ?Phycosiphon, ascribed to the Zoophycos ichnofacies, however, with distinct differences. In the Bidart section, early Danian dark-filled trace Fossil Assemblage is more abundant in large Thalassinoides, Zoophycos and larger Chondrites, and less abundant in Trichichnus and small Chondrites in comparison to the Sopelana section. Sopelana is thus interpreted as a more offshore, deeper section than Bidart although both were located in the upper bathyal zone of the basin. Oxygenation below the sediment–water interface was enough to favour a generalized total bioturbation of sediments. The presence of chemichnia and trace Fossils which tracemakers sequestered sediments from the sea floor in deep burrows (Zoophycos) suggests at least periodical food deficiency. The distribution and content of trace Fossils across the K/Pg boundary do not change significantly, revealing minor incidence of the K/Pg boundary event on the macrobenthic environment. The K/Pg boundary transition, including the boundary layer, is nearly totally bioturbated; hence a redistribution of microbiotic and abiotic components by tracemakers is possible.

  • ichnofabric evidence for the lack of bottom anoxia during the lower toarcian oceanic anoxic event in the fuente de la vidriera section betic cordillera spain
    PALAIOS, 2010
    Co-Authors: Francisco J Rodrigueztovar, Alfred Uchman
    Abstract:

    Abstract The early Toarcian (Early Jurassic) global marine mass extinction is usually related to the development of organic-rich sediments preserved as black shales and interpreted as a global oceanic anoxic event—the Toarcian Oceanic Anoxic Event (T-OAE). In the Betic Cordillera, southern Spain, the deep-marine Fuente de la Vidriera section contains the T-OAE as recorded at the westernmost part of the European Tethys. Ichnological analysis of the section indicates a relatively abundant and moderately diverse trace-Fossil Assemblage composed of Alcyonidiopsis isp., Chondrites isp., Nereites isp., Palaeophycus heberti, Planolites isp., Teichichnus isp., Thalassinoides isp., and Trichichnus linearis. A well-developed endobenthic multi-tiered community is characterized by an upper tier represented by homogenized sediment—individual burrows difficult to discern, a middle tier with a relatively diverse trace-Fossil Assemblage of mainly vagile deposit feeders, and a lower tier with activities of semisessile dep...

  • trace Fossils from late pleistocene varved lacustrine sediments in eastern lithuania
    Palaeogeography Palaeoclimatology Palaeoecology, 2009
    Co-Authors: Alfred Uchman, Vaidotas Kazakauskas, Algirdas Gaigalas
    Abstract:

    Abstract Trace Fossils Cochlichnus anguineus, Glaciichnium liebegastensis, Gordia carickensis (new combination, youngest occurrence), Gordia isp., Warvichnium ulbrichi, cf. Warvichnium isp. have been found in varved sediments of a small proglacial lake (17–16 kyr BP) in East Lithuania. They occur mostly in summer and transitional laminae along bunches of discrete microlaminae. Vertical reworking is absent. Horizontal distribution of trace Fossils along microlaminae studied in one varved package points to a patchy distribution of trace Fossils, resulting from a patchy distribution of food. Locally C. anguineus dominates and commonly this is the only trace Fossil. Its co-occurrence with G. liebegastensis is distinctly rarer than with other ichnotaxa, probably due to a competition between their tracemakers. The trace Fossil Assemblage can be ascribed to the Mermia ichnofacies, in which the Glaciichnium ichnocoenosis (arthropod trackways dominate) and Cochlichnus ichnocoenosis (grazing traces dominate) can be distinguished as the end members. Replacement of the Glaciichnium ichnocoenosis by the Cochlichnus ichnocoenosis can be interpreted as shallowing of hypolimnion and degrading ecological conditions.

  • oligocene trace Fossils from temporary fluvial plain ponds an example from the freshwater molasse of switzerland
    Eclogae Geologicae Helvetiae, 2004
    Co-Authors: Alfred Uchman, Milena Pikabiolzi, Peter A Hochuli
    Abstract:

    Numerous invertebrate trace Fossils and small rare vertebrate tracks are reported and described from the Upper Oligocene deposits of the Lower Fresh-water Molasse in eastern Switzerland. They are commonly accompanied by mud-cracks, raindrops, and plant remains, mostly leaves. The invertebrate trace Fossils were produced by different animals, mostly insect larvae, nematodes, and probably by molluscs, in desiccating pools on a fluvial plain of a braided river. The trace Fossil Assemblage differs from the Scoyenia ichnofacies which is typical for terrestrial fluvial plain environment. Instead, it resembles the impoverished Mermia ichnofacies which is probably common but poorly known in this environment. This ichnofacies corresponds to a low energy environment, most probably to fluvial plain ponds.

  • trace Fossils from lower miocene ottnangian molasse deposits of upper austria
    Palaeontologische Zeitschrift, 1995
    Co-Authors: Alfred Uchman, Hans Georg Krenmayr
    Abstract:

    Lower Miocene siliciclastic sediments of the Vockla Schichten and Atzbacher Sande, Austria, contain a shallow-water trace-Fossil Assemblage of the Cruziana ichnofacies includingSkolithos isp.,Planolites ? beverleyensis, Ophiomorpha annulata, O.nodosa, Rosselia socialis, Cylindrichnus concentricus, Scolicia isp., andBichordites monastiriensis. The ichnogenusRosselia and the ichnospeciesRosselia socialis are revised. Analysis ofScolicia isp. andB. monastiriensis provides new information about their morphology and ichnotaxonomy.

Jean-bernard Caron - One of the best experts on this subject based on the ideXlab platform.

  • ESM S1-S20,ESM 22 from Waptia fieldensis Walcott, a mandibulate arthropod from the middle Cambrian Burgess Shale
    2018
    Co-Authors: Jean Vannier, Cédric Aria, Rod S. Taylor, Jean-bernard Caron
    Abstract:

    S1- W. fieldensis, geographic and stratigraphic distribution. S2- Nebalia bipes (Phyllocarida), decay experiments. S3- W. fieldensis, Fossil Assemblage. S4- W. fieldensis, synonymy list. S5- W. fieldensis, type specimens. S6- W. fieldensis, measurements (1). S7- Nebalia bipes (Phyllocarida), morphology. S8- W. fieldensis, frontal part. S9- Vargula hilgendorfii (Ostracoda), labrum. S10- Cirolana harfordi (Isopoda), mandibles. S11- W. fieldensis, mandibles and maxillules. S12- W. fieldensis, post-maxillular cephalothoracic appendages. S13- W. fieldensis, post-maxillular cephalothoracic appendages (frontal view). S14- W. fieldensis, lamellate appendages. S15- Crangon crangon (Decapoda), gills. S16- W. fieldensis, measurements (2). S17- W. fieldensis, digestive system (1). S18- W. fieldensis, digestive system (2). S19- Cladogram (adult taxa). S20- List of characters. S22- Cladogram (larval and adult taxa)

  • ESM S1-S20,ESM 22;ESM S23;ESM S24 from Waptia fieldensis Walcott, a mandibulate arthropod from the middle Cambrian Burgess Shale
    2018
    Co-Authors: Jean Vannier, Cédric Aria, Rod S. Taylor, Jean-bernard Caron
    Abstract:

    S1- W. fieldensis, geographic and stratigraphic distribution. S2- Nebalia bipes (Phyllocarida), decay experiments. S3- W. fieldensis, Fossil Assemblage. S4- W. fieldensis, synonymy list. S5- W. fieldensis, type specimens. S6- W. fieldensis, measurements (1). S7- Nebalia bipes (Phyllocarida), morphology. S8- W. fieldensis, frontal part. S9- Vargula hilgendorfii (Ostracoda), labrum. S10- Cirolana harfordi (Isopoda), mandibles. S11- W. fieldensis, mandibles and maxillules. S12- W. fieldensis, post-maxillular cephalothoracic appendages. S13- W. fieldensis, post-maxillular cephalothoracic appendages (frontal view). S14- W. fieldensis, lamellate appendages. S15- Crangon crangon (Decapoda), gills. S16- W. fieldensis, measurements (2). S17- W. fieldensis, digestive system (1). S18- W. fieldensis, digestive system (2). S19- Cladogram (adult taxa). S20- List of characters. S22- Cladogram (larval and adult taxa).;S23. Waptia fieldensis Walcott, 1912 from the middle Cambrian (Series 3, Stage 5) Burgess Shale, British Columbia, Canada; animated reconstruction (L. Fields); general view.;S24. Waptia fieldensis Walcott, 1912 from the middle Cambrian (Series 3, Stage 5) Burgess Shale, British Columbia, Canada; animated reconstruction (L. Fields); anterior part