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Table of Contents - Special Paper 445

Deformation and Exhumation at Convergent Margins:
The Franciscan Subduction Complex

by Uwe Ring


Preface
Abstract

Introduction — Statement of the Problem
The Franciscan Triad — An Overview
  Franciscan Subduction Complex
Coast Range Fault Zone
Great Valley Forearc Basin
Burial, Accretion, and Average Rates of Exhumation
Current Tectonic Models for the Franciscan Subduction Complex
Open Questions and Aims of Study
Pressure-Temperature Evolution and Evidence for Solution-Mass-Transfer Deformation
  P-T Evolution of the Eastern Franciscan Belt
Northern California
Diablo Range
  P-T Evolution of the Central Franciscan Belt
P-T Evolution of the Forearc Basin
Evidence for SMT Deformation in the Eastern and Central Belts
SMT Deformation-Metamorphism Relationships
Methods of Strain Analysis, Sampling, and Data Collection
  Kinematics of Brittle Fault Zones
Preferred Method of Analysis
Sites of Fault Studies
Ductile Strain
Calculation of Exhumation by Vertical Ductile Thinning
Brittle Strain on the Coast Range Fault Zone
  Overview
Structures in the Coast Range Fault Zone
Brittle Strain Analysis
    Yolla Bolly Mountains
Diablo Range
  Interpretation of Data
    Constraints for Physical Setting of Fault Slip
Rotation Analysis
Brittle Strain in the Franciscan Subduction Complex
  Brittle Strain Analysis
    Northern California
Coastal Belt Thrust
Faults Related to the San Andreas Fault System
Ductile Strain and Mass Loss in the Eastern and Central Franciscan Belts
  Directions and Magnitudes of the Finite Stretches
    Northern California
Yolla Bolly Mountains
Leech Lake Mountain
Mendocino Pass Traverse
Cloverdale Transect
Bay Area
Diablo Range
Summary of Data
  Volume Strain and Strain Geometry
Internal Rotation and Strain Regime
Role of Ductile Thinning of the Overburden to Exhumation of the High-Pressure Metamorphic Rocks
  Residence Times of High-Pressure Rocks in the Franciscan Subduction Complex
Results
Discussion: Ductile Data
  Mass Loss, Pattern, and Magnitude of Ductile Deformation
Ductile Fabrics in Del Puerto Canyon
Ductile Strain, Exhumation of Franciscan High-Pressure Rocks, and the Role of SMT Deformation Mechanisms
Comparisons with Other Accretionary Wedges
Discussion: Brittle Data
  Tectonic Wedging
Kinematics of the Coast Range Fault Zone and Intra-Franciscan Faults
Possible Cause for Out-of-Sequence Thrusting in the Franciscan Subduction Complex
Discussion: Sedimentologic Aspects
  Emergence of Forearc High and Sedimentologic Record
Erosional Exhumation
Proposed Tectonic Evolution
Conclusions
Acknowledgments
Appendix
  Maps
Brittle Strain Analysis
    Coast Range Fault Zone
      Yolla Bolly Mountains
      Diablo Range
Intra-Franciscan Faults
      Northern California
      Coastal Belt thrust
      Faults related to the San Andreas fault system
References Cited