Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance
Fossil tetrapod footprints not only provide valuable information about trackmaker paleobiology but also to give insight into details of the depositional conditions of the substrate at the time of imprinting. Therefore, in the present study the mode of formation and taphonomy of footprints in differe...
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| Formato: | JOUR |
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| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_00310182_v291_n3-4_p388_Marsicano |
| Aporte de: |
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todo:paper_00310182_v291_n3-4_p388_Marsicano |
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| record_format |
dspace |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Argentina Basin evolution Lacustrine environment Paleobiology Taphonomy Tetrapod tracks Triassic basin evolution dinosaur footprint Gondwana herbivore ichnology lacustrine environment paleobiology paleosol ripple substrate taphonomy trace fossil trackway Triassic Argentina Animalia Archosauria Dinosauria Invertebrata Scoyenia Tetrapoda Therapsida |
| spellingShingle |
Argentina Basin evolution Lacustrine environment Paleobiology Taphonomy Tetrapod tracks Triassic basin evolution dinosaur footprint Gondwana herbivore ichnology lacustrine environment paleobiology paleosol ripple substrate taphonomy trace fossil trackway Triassic Argentina Animalia Archosauria Dinosauria Invertebrata Scoyenia Tetrapoda Therapsida Marsicano, C.A. Mancuso, A.C. Palma, R.M. Krapovickas, V. Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance |
| topic_facet |
Argentina Basin evolution Lacustrine environment Paleobiology Taphonomy Tetrapod tracks Triassic basin evolution dinosaur footprint Gondwana herbivore ichnology lacustrine environment paleobiology paleosol ripple substrate taphonomy trace fossil trackway Triassic Argentina Animalia Archosauria Dinosauria Invertebrata Scoyenia Tetrapoda Therapsida |
| description |
Fossil tetrapod footprints not only provide valuable information about trackmaker paleobiology but also to give insight into details of the depositional conditions of the substrate at the time of imprinting. Therefore, in the present study the mode of formation and taphonomy of footprints in different substrates was used to investigate the gait and walking dynamics of the trackmakers as well as a source of additional information on the environmental conditions of the track-bearing beds during imprinting. The analyzed section corresponds to thick Middle Triassic lacustrine/deltaic deposits of the Ischichuca/Los Rastros Formation (Ischigualasto-Villa Unión Basin) that crops out at the Quebrada de Ischichuca in northwestern Argentina. Part of the track-bearing surfaces correspond to the top of sandy distributary channel mouth bars in a distal delta front setting that were exposed along the lake margin during a lake level fall. Cross-cutting relationships observed among ripple-marks, the footprints, and invertebrate traces of a softground suite of the Scoyenia ichnofacies suggest an omission surface. Measured trackway orientations in the sandstones are perpendicular to the paleo-shoreline, with the animals coming and going along the exposed top of the bars, probably for drinking. Laterally, the distal delta front deposits interfinger with trackbearing wackestone beds of palustrine origin deposited in a restricted local embayment lateral to the delta influenced environment. Trackway orientations in the wackestones are, in contrast, consistent with the animals moving nearly parallel to the lake border, probably along a preferred route. Evidences of a relative high groundwater table at the time of imprinting in the track-bearing surfaces are revealed by the well developed rims of extruded sediment and collapsed digits in the studied tracks and the nearly absence of associated desiccation cracks on the same surfaces. Nevertheless, temporary emergence cannot be ruled out when paleosoil formation was probably promoted as can be observed in the microstructure of both sandstones and wackestones. Moreover, footprint preservation in the wackestones might have been enhanced by partial hardening of the trampled surface during subaerial exposure. Combining ichnofossil content and taphonomy with facies analysis we identified in the lower part of the Ischichuca/Los Rastros succession a relatively rapid withdrawal of the water basinward that was probably due to a forced regression during early rifting of basin evolution. Footprints can also provide valuable information about locomotion dynamics and trackmaker behavior. Thus, the sideways deformation observed in the studied footprints, attributed to basal archosaurs and putative basal dinosaurs, can be related to an outward rotation of the foot during the step cycle, a condition that might allied to the development of the parasagittal posture in Archosauria. Besides, the densely trampled surface described herein constitutes the first documented evidence of putative social behavior among therapsid dicynodonts, the most important group of herviborous animals in the early Mesozoic terrestrial ecosystems throughout Gondwana. © 2010 Elsevier B.V. All rights reserved. |
| format |
JOUR |
| author |
Marsicano, C.A. Mancuso, A.C. Palma, R.M. Krapovickas, V. |
| author_facet |
Marsicano, C.A. Mancuso, A.C. Palma, R.M. Krapovickas, V. |
| author_sort |
Marsicano, C.A. |
| title |
Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance |
| title_short |
Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance |
| title_full |
Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance |
| title_fullStr |
Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance |
| title_full_unstemmed |
Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance |
| title_sort |
tetrapod tracks in amarginal lacustrine setting (middle triassic, argentina): taphonomy and significance |
| url |
http://hdl.handle.net/20.500.12110/paper_00310182_v291_n3-4_p388_Marsicano |
| work_keys_str_mv |
AT marsicanoca tetrapodtracksinamarginallacustrinesettingmiddletriassicargentinataphonomyandsignificance AT mancusoac tetrapodtracksinamarginallacustrinesettingmiddletriassicargentinataphonomyandsignificance AT palmarm tetrapodtracksinamarginallacustrinesettingmiddletriassicargentinataphonomyandsignificance AT krapovickasv tetrapodtracksinamarginallacustrinesettingmiddletriassicargentinataphonomyandsignificance |
| _version_ |
1782030180340989952 |
| spelling |
todo:paper_00310182_v291_n3-4_p388_Marsicano2023-10-03T14:40:51Z Tetrapod tracks in amarginal lacustrine setting (Middle Triassic, Argentina): Taphonomy and significance Marsicano, C.A. Mancuso, A.C. Palma, R.M. Krapovickas, V. Argentina Basin evolution Lacustrine environment Paleobiology Taphonomy Tetrapod tracks Triassic basin evolution dinosaur footprint Gondwana herbivore ichnology lacustrine environment paleobiology paleosol ripple substrate taphonomy trace fossil trackway Triassic Argentina Animalia Archosauria Dinosauria Invertebrata Scoyenia Tetrapoda Therapsida Fossil tetrapod footprints not only provide valuable information about trackmaker paleobiology but also to give insight into details of the depositional conditions of the substrate at the time of imprinting. Therefore, in the present study the mode of formation and taphonomy of footprints in different substrates was used to investigate the gait and walking dynamics of the trackmakers as well as a source of additional information on the environmental conditions of the track-bearing beds during imprinting. The analyzed section corresponds to thick Middle Triassic lacustrine/deltaic deposits of the Ischichuca/Los Rastros Formation (Ischigualasto-Villa Unión Basin) that crops out at the Quebrada de Ischichuca in northwestern Argentina. Part of the track-bearing surfaces correspond to the top of sandy distributary channel mouth bars in a distal delta front setting that were exposed along the lake margin during a lake level fall. Cross-cutting relationships observed among ripple-marks, the footprints, and invertebrate traces of a softground suite of the Scoyenia ichnofacies suggest an omission surface. Measured trackway orientations in the sandstones are perpendicular to the paleo-shoreline, with the animals coming and going along the exposed top of the bars, probably for drinking. Laterally, the distal delta front deposits interfinger with trackbearing wackestone beds of palustrine origin deposited in a restricted local embayment lateral to the delta influenced environment. Trackway orientations in the wackestones are, in contrast, consistent with the animals moving nearly parallel to the lake border, probably along a preferred route. Evidences of a relative high groundwater table at the time of imprinting in the track-bearing surfaces are revealed by the well developed rims of extruded sediment and collapsed digits in the studied tracks and the nearly absence of associated desiccation cracks on the same surfaces. Nevertheless, temporary emergence cannot be ruled out when paleosoil formation was probably promoted as can be observed in the microstructure of both sandstones and wackestones. Moreover, footprint preservation in the wackestones might have been enhanced by partial hardening of the trampled surface during subaerial exposure. Combining ichnofossil content and taphonomy with facies analysis we identified in the lower part of the Ischichuca/Los Rastros succession a relatively rapid withdrawal of the water basinward that was probably due to a forced regression during early rifting of basin evolution. Footprints can also provide valuable information about locomotion dynamics and trackmaker behavior. Thus, the sideways deformation observed in the studied footprints, attributed to basal archosaurs and putative basal dinosaurs, can be related to an outward rotation of the foot during the step cycle, a condition that might allied to the development of the parasagittal posture in Archosauria. Besides, the densely trampled surface described herein constitutes the first documented evidence of putative social behavior among therapsid dicynodonts, the most important group of herviborous animals in the early Mesozoic terrestrial ecosystems throughout Gondwana. © 2010 Elsevier B.V. All rights reserved. Fil:Marsicano, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Mancuso, A.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Palma, R.M. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Krapovickas, V. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00310182_v291_n3-4_p388_Marsicano |