The Analysis of Diffuse Triple Junction Zones in Plate Tectonics and the Pirate Model of Western Caribbean Tectonics (SpringerBriefs in Earth Sciences)

Modern researchers in plate tectonics may be concerned with the analysis of distributed deformation across diffuse plate boundaries and triple junction zones. This book extends classic methods of kinematic analysis first developed in the 1960s to the more general scenarios of diffuse deformation zones between plates. The analytic methods presented specifically target the non-rigid deformation implied by unstable triple junction configurations. These methods are then applied to the tectonic evolution of western Caribbean region which provides new ways to test and challenge the established Pacific model of Caribbean tectonics. Possible advantages of the new Pirate model of Caribbean tectonics are discussed in terms of paleo-geography and paleo-ocean connections, as well as mineral and hydrocarbon potential and seismic risks across the region. Acknowledgments 5 Contents 6 Abbreviations 8 Chapter 1 9 Introduction 9 Chapter 2 19 Western Caribbean Tectonics 19 2.1 Tectonic Constraints 19 2.2 Theoretical Analysis of Western Caribbean Tectonics 24 2.2.1 Western Caribbean Plate Corners 30 2.2.1.1 Western Caribbean Plate Corners in the Pacific Model 30 2.2.1.2 Western Caribbean Plate Corners in the In-Situ Model 31 2.2.1.3 Western Caribbean Plate Corners in the Pirate Model 31 2.2.2 Relative Plate Motions 33 2.2.3 Western Caribbean Arc Deformation Style 34 2.3 Review of Western Caribbean and Gulf of Mexico Tectonics 35 2.3.1 Shortening at the Eastern Caribbean Plate Boundary 35 2.3.2 Extension Conjugate to Eastern Caribbean Shortening 36 2.3.3 Displacements at the Western Caribbean Plate Corners 40 2.3.3.1 Global Rotation Model 40 2.3.3.2 X-Directed Displacements 40 2.3.3.3 Y-Directed Displacements 41 2.3.3.4 Residual Displacements at the Western Caribbean Plate Corners 42 2.3.4 Western Caribbean Microplates 43 2.3.4.1 The Chortis, Chiapas, and Yucatan Blocks 43 2.3.4.2 The Transient Mexican Microplates 44 2.3.4.3 Microplates Accreted to Northwest South America: Northern Andes, Maracaibo, and Bonaire Blo 46 2.3.4.4 The Central American Forearc Sliver, Panama and Choco Blocks 47 2.4 Discussion 49 2.4.1 Consistency with Known Data 49 2.4.2 Predictive Power 49 2.4.3 A New, Multi-Mode Model for Western Caribbean Tectonics 54 2.4.4 The Chortis Block Controversy 56 2.4.5 Neo-Caribbean Tectonics 59 2.4.6 Meeting of the Americas 59 2.4.7 Age of Gulf of Mexico Opening 60 2.4.8 A Geodynamic Model for the Western Caribbean Region 60 2.5 Conclusions 61 References 62 Chapter-3 69 Normalization Analysis for Possibly-Unstable Triple Junction Zones 69 3.1 Introduction 69 3.2 Step 1: Define a Doubly-Tangent, Moving Euclidean Tectonic Reference Frame 71 3.3 Step 2: Determine Compatibility of Major Plate Motions and Plate Boundary Orientations 74 3.4 Step 3: Determine the Stability of the Normalized, Hypothetical Triple Junction 78 3.5 Step 4: Identify End-Member Nonrigid Solutions for an Unstable Triple Junction 79 References 82 Front Matter....Pages i-ix Introduction....Pages 1-10 Western Caribbean Tectonics....Pages 11-60 Normalization Analysis for Possibly-Unstable Triple Junction Zones....Pages 61-75