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Table of Contents - Special Paper 335: |
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Tectonosomes and Olistostromes in the Argille Scagliose of the northern Apennines, Italy |
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| Abstract | 1 | |
| Introduction | 1 | |
| Structural setting of the Ligurian units in the Northern Apennines |
3 |
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| Major units and structures | 6 | |
| Ligurian nappe | 7 | |
| Epiligurian successions | 7 | |
| Other structural units | 7 | |
| Compressional history | 8 | |
Controversy regarding the argille scagliose and olistostromes |
8 |
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| Criteria for field- to map-scale distinction of tectonosomes and olistostromes in the argille scagliose of the Bologna Apennines |
10 |
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| Mesoscopic characteristics | 11 | |
| Tectonosomes | 11 | |
| Olistostromes | 12 | |
| Microscopic to mesoscopic characteristics | 14 | |
| Mappable characteristics, original stratigraphy, present stratigraphy | 14 | |
| Tectonosomes | 14 | |
| Olistostromes | 16 | |
| Etymology and usage of the terms | 16 | |
| Tectonosomes | 16 | |
| Olistostromes | 19 | |
Stratigraphy and setting of tectonosomes, olistostromes, and related Epiligurian deposits in the Bologna Apennines |
19 |
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| Stratigraphy of tectonosomes and Ligurian olistostromes | 19 | |
| LC units of tectonosomes | 19 | |
| UCE units of tectonosomes | 20 | |
| Tectonosomes as a tectono-stratigraphic unit from a single Ligurian sequence | 20 | |
| Ligurian olistostromes | 20 | |
| Stratigraphy of the Epiligurian deposits | 20 | |
| Stratigraphy of the Epiligurian olistostromes | 21 | |
| Normal stratigraphic units associated with the olistostromes | 21 | |
| Structural setting of the Bologna Apennines | 21 | |
| External structural belt | 21 | |
| Internal structural belt | 21 | |
Tectonosomes |
23 |
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| Stratal disruption in UCE units | 23 | |
| UCE2 Unit | 23 | |
| UCE1 Unit | 23 | |
| Mechanisms of mesoscopically ductile deformation | 25 | |
| Stratal disruption in LC units | 28 | |
| Macroscale to mesoscale observations | 29 | |
| Mesoscale observations | 29 | |
| Microscale observations: The scaly fabric of the matrix | 34 | |
| Interpretation of microscale to mesoscale structures in the LC units | 37 | |
| Relationships between the microscale to mesoscale and the mesoscale to macroscale structures in the LC units | 42 | |
| Structural interaction among the tectonosome units | 43 | |
| Structural evolution of the tectonosomes | 43 | |
| LC units | 43 | |
| UCE units | 45 | |
| Relationships of UCE and LC | 45 | |
| Regional meaning of the tectonosome structures | 45 | |
| Lozenge shape in tectonosomes: Shear lenses from macroscale to microscale | 46 | |
Olistostromes |
46 |
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| Epiligurian olistostromes (EO) | 49 | |
| Texture | 49 | |
| Composition and origin of the clasts | 50 | |
| Disposition | 51 | |
| Ligurian olistostromes | 52 | |
| Texture | 52 | |
| Composition | 52 | |
| Disposition and setting | 52 | |
| Romagna-Umbria olistostromes | 53 | |
| Visignano-Bordignano olistostrome | 53 | |
| Ca Nova Pagliarizzo and Castello di Fiagnano olistostromes | 53 | |
| Olistostromes: General characters | 54 | |
| Genesis of the olistostromes | 54 | |
| Mixing of different lithotypes: Present-day and ancient models | 55 | |
| Depositional mechanism | 58 | |
| Interpretation of the studied olistostromes | 58 | |
Summary of depositional and deformational history and setting of tectonosomes and olistostromes |
61 |
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| Pre-late Eocene (Eoalpine-Mesoalpine tectonics) | 61 | |
| Late Eocene-recent (Neoalpine tectonics) | 62 | |
Acknowledgments |
63 |
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| References cited | 64 | |