Heat flow, tectonics, and fluid circulation at the toe of the Barbados ridge accretionary prism

Detailed patterns of near surface tectonics and heat flow were investigated at two locations at the toe of the Barbados Ridge accretionary prism. At the two locations, in the thickly sedimented southern portion of the prism near 12°20′N and in the northern area drilled during Ocean Drilling Program (ODP) leg 110 near 15°32′N, relative highs of heat flow were associated with zones of thrusting. We attribute them to upward advection of water rising from the decollement along faults through the sediments. In the ODP area, a significant heating plate effect from warm fluids flowing along the decollement and thrusts is required to account for the high regional heat flow. This effect implies high rates of fluid flow at the decollement, which can only be non-steady state or would require massive lateral transport of fluids along strike.

[1]  Yaolin Shi,et al.  Generation of high pore pressures in accretionary prisms: Inferences from the Barbados Subduction Complex , 1988 .

[2]  C. Hemleben,et al.  Offscraping and underthrusting of sediment at the deformation front of the Barbados Ridge: Deep Sea Drilling Project Leg 78A , 1982 .

[3]  O. E. S. Party.  Expulsion of fluids from depth along a subduction-zone decollement horizon , 1987, Nature.

[4]  G. Westbrook,et al.  Cross section of an accretionary wedge: Barbados Ridge complex , 1988 .

[5]  R. Huene.  Tectonic Processes Along the Front of Modern Convergent Margins--Research of the Past Decade , 1984 .

[6]  Thomas H. Jordan,et al.  Present‐day plate motions , 1977 .

[7]  X. Pichon,et al.  Detailed structure and possible fluid paths at the toe of the Barbados accretionary wedge (ODP Leg 110 area) , 1990 .

[8]  S. Stein,et al.  A test of alternative Caribbean Plate relative motion models , 1988 .

[9]  B. Biju-Duval,et al.  Multibeam bathymetric survey and high resolution seismic investigations on the Barbados Ridge complex (Eastern Caribbean): A key to the knowledge and interpretation of an accretionary wedge , 1982 .

[10]  D. Karig,et al.  Dewatering and extensional deformation of the Shikoku Basin hemipelagic sediments in the Nankai Trough , 1988 .

[11]  X. Pichon,et al.  Fluid venting along Japanese trenches: tectonic context and thermal modeling , 1989 .

[12]  G. Westbrook,et al.  Contrasting geothermal regimes of the Barbados Ridge Accretionary Complex , 1990 .

[13]  J. D. Bredehoeft,et al.  Rates of vertical groundwater movement estimated from the Earth's thermal profile , 1965 .

[14]  G. Westbrook,et al.  Geophysical survey of a mud volcano seaward of the Barbados Ridge Accretionary Complex , 1988 .

[15]  G. Massoth,et al.  Oregon Subduction Zone: Venting, Fauna, and Carbonates , 1986, Science.

[16]  M. Hounslow,et al.  Transient fluid flow through the toe of the Barbados Accretionary Complex: Constraints from ocean Drilling Program Leg 110 heat row studies and simple models , 1990 .