Abstract Although the concept of ichnology as a single coherent field arose in the nineteenth cen... more Abstract Although the concept of ichnology as a single coherent field arose in the nineteenth century, the endeavor of understanding traces is old as civilization and involved cultural areas worldwide. In fact, fossil and recent traces were recognized since prehistoric times and their study emerged from the European Renaissance. This progression, from empirical knowledge toward the modern concepts of ichnology, formed a major research field which developed on a global scale. This report outlines the history of ichnology by (1) exploring the individual cultural areas, (2) tracing a comprehensive bibliographic database, and (3) analyzing the evolution of ichnology semiquantitatively and in a graphical form (“tree of ichnology”). The results form a review and synthesis of the history of ichnology, establishing the individual and integrated importance of the different ichnological schools in the world.
Terra Nova, 22, 195–202, 2010Terra Nova, 22, 195–202, 2010AbstractA semi-quantitative analysis of... more Terra Nova, 22, 195–202, 2010Terra Nova, 22, 195–202, 2010AbstractA semi-quantitative analysis of the endobenthic activity across the Permo-Triassic boundary (PTB) was carried out on a ∼445-m-thick well core interval from the Persian Gulf by logging the degree of bioturbation, trace fossil distribution and ichnodiversity (ID). This analysis enables for the first time the evaluation of recovery of endobenthic organisms after the end-Permian mass extinction by direct comparison of post-extinction (Lower Triassic) with pre-extinction (Upper Permian) units. The results indicate that the studied shallow-marine carbonate platform within an equatorial setting acted as oxygenated refugee for the biotic recovery. Traces of suspension and deposit feeders reappear simultaneously shortly after the extinction event, but are reduced in size. Macroborings – so far unknown from the Lower Triassic – occur where suitable firm or hard substrate was available. Recovery took place in two phases: Early Induan (50% pre-extinction ID and 20–30% bioturbation) and Late Induan (>75% ID and almost 90% bioturbation re-established).A semi-quantitative analysis of the endobenthic activity across the Permo-Triassic boundary (PTB) was carried out on a ∼445-m-thick well core interval from the Persian Gulf by logging the degree of bioturbation, trace fossil distribution and ichnodiversity (ID). This analysis enables for the first time the evaluation of recovery of endobenthic organisms after the end-Permian mass extinction by direct comparison of post-extinction (Lower Triassic) with pre-extinction (Upper Permian) units. The results indicate that the studied shallow-marine carbonate platform within an equatorial setting acted as oxygenated refugee for the biotic recovery. Traces of suspension and deposit feeders reappear simultaneously shortly after the extinction event, but are reduced in size. Macroborings – so far unknown from the Lower Triassic – occur where suitable firm or hard substrate was available. Recovery took place in two phases: Early Induan (50% pre-extinction ID and 20–30% bioturbation) and Late Induan (>75% ID and almost 90% bioturbation re-established).
A horizon with pot casts (potholes) is described from shallow-marine limestones of thespinosus-zo... more A horizon with pot casts (potholes) is described from shallow-marine limestones of thespinosus-zone (‘Discitesschichten’, Upper Muschelkalk) near Weimar/Thuringia. The erosional structures are not developed as sole marks but occur as isolated structures. They differe distinctly in size and composition from pot casts described from the Muschelkalk of Southern Germany. Vertical sedimentary zonation and varying sediment infill in the structures suggest continuous erosion and deposition contemporaneous with the background sedimentation. Deposition may have been caused by oscillatory and unidirectional flows as well as a long period of micrite deposition. Early diagenetic deformations (e.g. dewatering, brecciation, pressure solution) have controlled by a higher continuous water flux inside the pot casts and higher intergranular dispersal pressure.
In the German Triassic of Thuringia, the Lower Muschelkalk sequence can be subdivided by applicat... more In the German Triassic of Thuringia, the Lower Muschelkalk sequence can be subdivided by application of ichnological methods. Three ichnofacies with five ichnofabrics are described. In accordance with the lithological features, trace fossils are found to defining parasequences on the basis of a regular change of bioturbation. Furthermore, it is possible to establish deepening-upward cycles. The reconstruction of parasequences allows the establishment of a high-resolution sequence stratigraphy. The position of the maximum flooding surface can be identified in the Terebratula Member and is developed in a condensed interval. The most significant of the additional major marine flooding surfaces is found at the top of the Upper Oolith Bed, characterized by lithostratigraphy, ichnology, biostratigraphy and parasequence thickness trends.
Abstract Although the concept of ichnology as a single coherent field arose in the nineteenth cen... more Abstract Although the concept of ichnology as a single coherent field arose in the nineteenth century, the endeavor of understanding traces is old as civilization and involved cultural areas worldwide. In fact, fossil and recent traces were recognized since prehistoric times and their study emerged from the European Renaissance. This progression, from empirical knowledge toward the modern concepts of ichnology, formed a major research field which developed on a global scale. This report outlines the history of ichnology by (1) exploring the individual cultural areas, (2) tracing a comprehensive bibliographic database, and (3) analyzing the evolution of ichnology semiquantitatively and in a graphical form (“tree of ichnology”). The results form a review and synthesis of the history of ichnology, establishing the individual and integrated importance of the different ichnological schools in the world.
Terra Nova, 22, 195–202, 2010Terra Nova, 22, 195–202, 2010AbstractA semi-quantitative analysis of... more Terra Nova, 22, 195–202, 2010Terra Nova, 22, 195–202, 2010AbstractA semi-quantitative analysis of the endobenthic activity across the Permo-Triassic boundary (PTB) was carried out on a ∼445-m-thick well core interval from the Persian Gulf by logging the degree of bioturbation, trace fossil distribution and ichnodiversity (ID). This analysis enables for the first time the evaluation of recovery of endobenthic organisms after the end-Permian mass extinction by direct comparison of post-extinction (Lower Triassic) with pre-extinction (Upper Permian) units. The results indicate that the studied shallow-marine carbonate platform within an equatorial setting acted as oxygenated refugee for the biotic recovery. Traces of suspension and deposit feeders reappear simultaneously shortly after the extinction event, but are reduced in size. Macroborings – so far unknown from the Lower Triassic – occur where suitable firm or hard substrate was available. Recovery took place in two phases: Early Induan (50% pre-extinction ID and 20–30% bioturbation) and Late Induan (>75% ID and almost 90% bioturbation re-established).A semi-quantitative analysis of the endobenthic activity across the Permo-Triassic boundary (PTB) was carried out on a ∼445-m-thick well core interval from the Persian Gulf by logging the degree of bioturbation, trace fossil distribution and ichnodiversity (ID). This analysis enables for the first time the evaluation of recovery of endobenthic organisms after the end-Permian mass extinction by direct comparison of post-extinction (Lower Triassic) with pre-extinction (Upper Permian) units. The results indicate that the studied shallow-marine carbonate platform within an equatorial setting acted as oxygenated refugee for the biotic recovery. Traces of suspension and deposit feeders reappear simultaneously shortly after the extinction event, but are reduced in size. Macroborings – so far unknown from the Lower Triassic – occur where suitable firm or hard substrate was available. Recovery took place in two phases: Early Induan (50% pre-extinction ID and 20–30% bioturbation) and Late Induan (>75% ID and almost 90% bioturbation re-established).
A horizon with pot casts (potholes) is described from shallow-marine limestones of thespinosus-zo... more A horizon with pot casts (potholes) is described from shallow-marine limestones of thespinosus-zone (‘Discitesschichten’, Upper Muschelkalk) near Weimar/Thuringia. The erosional structures are not developed as sole marks but occur as isolated structures. They differe distinctly in size and composition from pot casts described from the Muschelkalk of Southern Germany. Vertical sedimentary zonation and varying sediment infill in the structures suggest continuous erosion and deposition contemporaneous with the background sedimentation. Deposition may have been caused by oscillatory and unidirectional flows as well as a long period of micrite deposition. Early diagenetic deformations (e.g. dewatering, brecciation, pressure solution) have controlled by a higher continuous water flux inside the pot casts and higher intergranular dispersal pressure.
In the German Triassic of Thuringia, the Lower Muschelkalk sequence can be subdivided by applicat... more In the German Triassic of Thuringia, the Lower Muschelkalk sequence can be subdivided by application of ichnological methods. Three ichnofacies with five ichnofabrics are described. In accordance with the lithological features, trace fossils are found to defining parasequences on the basis of a regular change of bioturbation. Furthermore, it is possible to establish deepening-upward cycles. The reconstruction of parasequences allows the establishment of a high-resolution sequence stratigraphy. The position of the maximum flooding surface can be identified in the Terebratula Member and is developed in a condensed interval. The most significant of the additional major marine flooding surfaces is found at the top of the Upper Oolith Bed, characterized by lithostratigraphy, ichnology, biostratigraphy and parasequence thickness trends.
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