Seismic Reflection Imaging of the Subducting Juan De Fuca Plate
__ ____ _ _N_ A_TU�R_E_v_o_L_ . _31_9_1_6_JAN_uA_R_Y 1 9_86 =-=21:.:.o __________ __ _____ LETIERSTQNATLJRE _ __ _ _ Seismic reflection imaging of that is underplated. These findingslead us to speculate that success ive underplating of oceanic lithosphere may be an important pro the subducting Juan de Fuca plate cess in the evolution and growth of continents. A total of 205 km of deep seismic reflection data have been A. R. M. J. G. Green*, Clowest, C. YoratM, collected along the fourprofiles shown in the simplified geologi C. Spencer*, E. R. Kanasewich§, M. T. Brandon:j: cal map of southeastern Vancouver Island (Fig. 1). The VISPl & A. Sutherland Brown:j: line crosses the width of the island and is almost coincident with one of the gravity profiles studied by Riddihough 10 and * Division of Seismology and Geomagnetism, Department of Energy, with the combined onshore/ offshore seismic refraction line of Mines and Resources, I Observatory Crescent, Ottawa, Ontario, Spence et al.17• Some three-dimensional control on the interpre Canada KIA OY3 tation of VISPl is available from the VISP3 line located 15- t Department of Geophysics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T IWS 20 km to the east and from a short test line described by Clowes 18 :j: Pacific Geoscience Centre, Department of Energy, Mines and et al. • The two southeasterly lines, VISP2 and VISP4, were Resources, Sidney, British Columbia, Canada V8L 4B2 designed to determine the attitudes and significance of the San § Department of Physics, University of Alberta, Edmonton, Alberta, Juan, Survey Mountain and Leech River faults.
[Show full text]