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JOURNAL OF GEOPHYSICAL RESEARCH,
VOL. 108, NO. B12,
2555,
doi:10.1029/2002JB002240,
2003
Three-dimensional numerical simulation of fluid flow and heat transport within the Barbados Ridge accretionary complex
Paula A. Cutillo
Department of Geological Sciences, University of Colorado, Boulder, Colorado, USA
Elizabeth J. Screaton
Department of Geological Sciences, University of Florida, Florida, USA
Shemin Ge
Department of Geological Sciences, University of Colorado, Boulder, Colorado, USA
Abstract
The thickness of the Barbados accretionary prism varies along strike. The increased thickness of the prism to the south is
believed to affect the transport of heat by fluids, resulting in anomalously high heat flow at the deformation front. We utilized
a coupled three-dimensional numerical fluid flow and heat transport model to investigate the effect of variable accretionary
prism thickness on fluid flow patterns and heat transport in the décollement zone. The variation in sediment thickness produced
along-strike fluid flow in the more permeable décollement. Although surface heat flow is higher for simulations where flow
occurs along both the décollement and underthrust sediments, the resultant advective heat transport was not sufficient to
appreciably raise steady state surface heat flow at the latitude of the Ocean Drilling Program transect. Simulated temperatures
in the décollement were consequently much lower than in situ borehole measurements, suggesting an additional source of warmer
fluid. We then investigated the transient hydrologic and thermal response of the system to enhanced fault permeability. Model
results provide insight into the degree to which episodic faulting may drive fluid flow and heat transport within subduction
complexes. A transient scenario in which décollement permeability was increased two orders of magnitude with fluid flow along
both the décollement and underthrust sediments caused the temperature gradient at the location of the drill sites to increase
by a factor of two within 7100 years. The results of the three-dimensional numerical simulations indicate that while both
along-strike advective heat transport and transient fluid flow events should be considered in the heat flow distribution of
the northern Barbados accretionary complex, the effects of episodic fluid flow are more significant.
Received 10
October
2002;
accepted 12
August
2003;
published 11
December
2003.
Index Terms: 3210 Mathematical Geophysics: Modeling; 1878 Hydrology: Water/energy interactions; 8045 Structural Geology: Role of fluids; 8105 Tectonophysics: Continental margins and sedimentary basins.
Read Full Article (file size: 708826 bytes) Cited by
Citation: Cutillo, P. A., E. J. Screaton, and S. Ge
(2003),
Three-dimensional numerical simulation of fluid flow and heat transport within the Barbados Ridge accretionary complex,
J. Geophys. Res.,
108(B12),
2555,
doi:10.1029/2002JB002240.
Copyright 2003 by the American Geophysical Union.
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