The Analysis of Diffuse Triple Junction Zones in Plate Tectonics and the Pirate Model of Western Caribbean Tectonics

Dr. Fraser Keppie is employed as a geologist with the Geological Services Division, Department of Natural Resources, Nova Scotia. His initial research and mapping in Nova Scotia is focused on compiling and extending tectonic models for the assembly and breakup of Pangea, with an emphasis on understanding the mechanisms of formation and evolution of the Devono-Carboniferous Maritimes Basin and its hydrocarbon potential. Prior to 2010, Fraser completed undergraduate degrees in geology and computer science at St. Francis Xavier and Acadia Universities, respectively, a doctoral degree in tectonics at McGill University, and a post-doctoral appointment at Caltech in geodynamics.

Introduction.- Western Caribbean Tectonics.- Abstract.-Tectonic constraints.- Theoretical analysis of Western Caribbean tectonics.- Western Caribbean Plate corners.- Relative Plate motions.- Western Caribbean arc deformation style.- Review of Western Caribbean and Gulf of Mexico tectonics.- Shortening at the Eastern Caribbean Plate boundary.- Extension conjugate to Eastern Caribbean shortening.- Displacements at the Western Caribbean Plate corners.- Western Caribbean microplates.- Discussion.- Consistency with known data.- Predictive Power.- A new, multi-mode model for Western Caribbean tectonics.- The Chortis Block controversy.- Neo-Caribbean tectonics.- Meeting of the Americas.- Age of Gulf of Mexico opening.- A geodynamic model for the Western Caribbean region.- Conclusions.- References.- Normalization analysis for possibly unstable triple junction zones.- Abstract.- Introduction.- Step 1: Define a doubly-tangent, moving Euclidean tectonic reference frame.- Step 2: Determine compatibility of major plate motions and plate boundary orientations.- Step 3: Determine the stability of the normalized, hypothetical triple junction.- Step 4: Identify end-member nonrigid solutions for an unstable triple junction.- References.