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Showing 1 to 11 of 11 for “"trace fossil"”.
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Ichnotaxonomic assessment of Mazon Creek area trace fossils, Illinois, USA
… organisms preserved within siderite concretions. Trace fossils, though less well known, also occur in concretions. Several hundred trace-fossil-bearing concretions were examined from collections at The Field Museum, Chicago, and The University of Kansas Natural History Museum, Lawrence. …
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Sedimentology, ichnology and sequence stratigraphy of the Lower Cambrian Gog Group, southern Rocky Mountains, Canada
… a sequence-stratigraphic framework; (6) document trace-fossil occurrences; and (7) characterize different trace-fossil assemblages in terms of colonization trends and prevailing paleoenvironmental conditions. The Gog Group in this area has historically comprised four units, the Fort Mountain, Lake …
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Revision and description of Keuper (Middle Ladinian to Rhaetian) invertebrate trace fossils from the southern part of the Germanic Basin and studies of related material
The invertebrate trace fossils from the Keuper (Upper Triassic) of the southern part of the Germanic Basin are revised. The Keuper sediments of the Germanic Basin are predominantly composed of rocks representing various nonmarine environments dominated by red-bed facies. The Würzburg Formation, the …
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The Cambrian: Sedimentary controls on marine ichnology and stratigraphic time at outcrop
… valuable archive for understanding this dynamic: trace fossil diversity (ichnodiversity) reflects ecological diversity and evolutionary trends, while also providing insight into how erosion, deposition, and sedimentary stasis affected the registration of such signals within the stratigraphic …
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Redefining the Treptichnus pedum zone at the Global Boundary Stratotype Section and Point (GSSP): A critical reassessment of the Ediacaran-Cambrian boundary.
… Cambrian fauna. Due to the paucity of the body-fossil record, trace fossils often offer the only available insight into these evolutionary milestones, representing a continuous record through the late Ediacaran-early Cambrian. The Chapel Island Formation (CIF) of the Burin Peninsula, …
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Paleontology of brackish-water faunas in two tongues of the Cannonball Formation (Paleocene, Danian), Slope and Golden Valley counties, southwestern North Dakota
… sections were sampled systematically for microfossils and macroinvertebrates, and 13 species in 12 genera ware identified. Both formations can be distinguished by their contained fossils. The fauna of the U tongue of the Cannonball consists of three bivalves (Corbicula berthoudi?, Corbula …
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Constraining the Ediacaran-Cambrian boundary in South China using acanthomorphic acritarchs and Palaeopascichnus fossils
… as the first appearance of the branching trace fossil Treptichnus pedum. However, T. pedum has been subsequently found below the GSSP, and its distribution is largely restricted to sandstone facies where chemostratigraphic correlation tools are difficult to apply. Thus, the stratigraphic …
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The geochemistry of late Precambrian weathering profile northwest Scotland
… the Cambrian Unconformity at Rispond represent a fossil soil profile. These rocks contain pyrophyllite, considered to have been formed by low-grade metamorphism rather than by weathering. Three possible modes of origin have been considered, and that involving the weathering of potassium feldspar …
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Stratigraphy and depositional environments of the Fox Hills Formation (Upper Cretaceous), Bowman County, North Dakota
<p> The sedimentary structures, trace fossils, and lithology of the Upper Cretaceous Fox Hills Formation in Bowman County, North Dakota, were studied during the summer of 1979 and the spring of 1983. Twenty-three stratigraphic sections were measured and described and lithologic samples were …
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Understanding the theatre of terrestrialization: Silurian-Devonian sedimentary landscapes and continental ecosystems
… ichnofaunas appear to be dominated by traces produced by arthropods and vermiform organisms, suggesting these were key constituents of colonizing communities. Numerous motifs and recurring signatures are apparent across the case studies, with several key traces occurring almost …
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Stratigraphy, Sedimentology, and Ichnology of the Middle Cambrian to Lower Ordovician Deposits in Subsurface Western Canada
… stressful settings in the Early Phanerozoic. Trace fossil analyses indicate the combinations and ranking of stress factors affecting the colonizing fauna is diverse throughout the succession. BSU fan-delta deposits display sparse to moderate bioturbation in mid- to outer-delta subaqueous …