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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 |
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 |