Extension in Mona Passage, Northeast Caribbean
MetadataShow full item record
As shown by the recent Mw 7.0 Haiti earthquake, intra-arc deformation, which accompanies the subduction process, can present seismic and tsunami hazards to nearby islands. Spatially-limited diffuse tectonic deformation within the Northeast Caribbean Plate Boundary Zone likely led to the development of the submerged Mona Passage between Puerto Rico and the Dominican Republic. GPS geodetic data and a moderate to high level of seismicity indicate that extension within the region is ongoing. Newly-collected high-resolution multibeam bathymetry and multi-channel seismic reflection profiles and previously-collected samples are used here to determine the tectonic evolution of the Mona Passage intra-arc region. The passage is floored almost completely by Oligocene–Pliocene carbonate platform strata, which have undergone submarine and subaerial erosion. Structurally, the passage is characterized by W- to NNW-trending normal faults that offset the entire thickness of the Oligo–Pliocene carbonate platform rocks. The orientation of these faults is compatible with the NE-oriented extension vector observed in GPS data. Fault geometry best fits an oblique extension model rather than previously proposed single-phase, poly-phase, bending-moment, or rotation extension models. The intersection of these generally NW-trending faults in Mona Passage with the N–S oriented faults of Mona Canyon may reflect differing responses of the brittle upper-crust, along an arc–forearc rheological boundary, to oblique subduction along the Puerto Rico trench. Several faults within the passage, if ruptured completely, are long enough to generate earthquakes with magnitudes on the order of Mw 6.5–7.
This paper is not subject to U.S. copyright. The definitive version was published in Tectonophysics 493 (2010): 74-92, doi:10.1016/j.tecto.2010.07.002.
Showing items related by title, author, creator and subject.
The Kuroshio Extension : a leading mechanism for the seasonal sea-level variability along the west coast of Japan Ma, Chao; Yang, Jiayan; Wu, Dexing; Lin, Xiaopei (2009-10-08)Sea level changes coherently along the two coasts of Japan on the seasonal time scale. AVISO satellite altimetry data and OFES (OGCM for the Earth Simulator) results indicate that the variation propagates clockwise from ...
The Kuroshio Extension northern recirculation gyre : profiling float measurements and forcing mechanism Qiu, Bo; Chen, Shuiming; Hacker, Peter; Hogg, Nelson G.; Jayne, Steven R.; Sasaki, Hideharu (American Meteorological Society, 2008-08)Middepth, time-mean circulation in the western North Pacific Ocean (28°–45°N, 140°–165°E) is investigated using drift information from the profiling floats deployed in the Kuroshio Extension System Study (KESS) and the ...
Spatio-temporal evolution of strain accumulation derived from multi-scale observations of Late Jurassic rifting in the northern North Sea : a critical test of models for lithospheric extension Cowie, Patience A.; Underhill, John R.; Behn, Mark D.; Lin, Jian; Gill, Caroline E. (2005-01-23)We integrate observations of lithospheric extension over a wide range of spatial and temporal scales within the northern North Sea basin and critically review the extent to which existing theories of lithospheric deformation ...