CONSTRAINING CUBAN SUBDUCTION MIGRATION FROM ALONG-STRIKE VARIATIONS IN OROGENIC CONVERGENCE?

This study tests the standard view that the Cuban subduction zone terminated at a major transform fault along the northern Caribbean plate boundary in the late Cretaceous and early Cenozoic. This standard view implies significant net convergence along the entire length of northern Cuba and an Euler pole for relative Cuba-North America motion that is very distal to the north (or south). In contrast, geological reports have described how the evidence for subduction or net inter-plate shortening experienced along the orogenic front of northern Cuba decreases and potentially disappears moving to the northwest. This along-strike variation in net convergence could be consistent with an Euler pole governing relative Cuba-North America motion that lay very near to northwest Cuba instead. The validity of using surface evidence to estimate net convergence along the Cuban subduction zone is reviewed here and possible implications for Caribbean tectonic models are considered.