Print this pageCause-and-Effect Relationship Between Discontinuities of the Continental Crust and Oceanic Fracture Zones in Marginal Sedimentary Basins
An integrated analysis of regional geological-structural and potential field maps shows that the major discontinuities of the oceanic crust, mostly associated to fracture zones, have a direct relationship to important discontinuities in the continental crust, which are represented by crustal limits, sutures, main lineaments and structural trends. This relationship indicates that oceanic fracture zones normally nucleate during continental breakup on major discontinuities of the continental crust, mostly on boundaries of geologic provinces or on zones of crossing anisotropy trends. Once oceanic fracture zones are preferential routes for tectonic reactivations driven by activities in the mid-oceanic spreading centers, their terminations associated with discontinuities of the continental crust make these zones more favorable to recurrent tectonic reactivations throughout the passive-margin stage of the basin. These zones are therefore potential areas for structural trap formation, as well as for the developing of favorable vertical migration pathways connecting source rocks and reservoirs. Examples from Brazilian marginal Atlantic basins show clearly these relationships.
AAPG Search and Discover Article #90100©2009 AAPG International Conference and Exhibition 15-18 November 2009, Rio de Janeiro, Brazil