AN: T71E-06TI: Correlation of Deep Crustal Reflectors of the ACCRETE Seismic Section With Surface Exposures of Rocks Formed in the Lower CrustAU: Lincoln S. HollisterAF: Dept.of Geosciences Princeton University Princeton New Jersey 08544-1003 USAEM: linc@geo.princeton.eduAU: Chris AndronicosAF: Dept.of Geosciences Princeton University Princeton New Jersey 08544-1003 USAEM: cla@princeton.eduAU: John DieboldAF: Lamont-Doherty Columbia University Rt. 9W P.O. Box 1000 Palisades New York 10964EM: johnd@lamont.ldgo.columbia.eduAB: The goal of the ACCRETE project is to define the history of terrane accretion and continental crust evolution between latitudes $53\deg$N and $57\deg$N, across the Coast Mountains of British Columbia and southeast Alaska. In order to help obtain a 3-D image of the major geologic features, a vertical seismic section was made along a fiord that crosses the north-northwest trending Coast Mountains. An important step in interpreting this seismic section is to correlate mid to lower crustal seismic features observed in the seismic section to rocks presently exposed on the surface. This can be done because the mid to lower crustal rocks exposed on the surface project from south of the seismic transect into the vertical plane of the seismic section. Preliminary observations show that the Shames mylonite zone, an over 4 km thick extensional detachment fault mapped along the east side of the Coast Mountains, reaches the plane of the seismic section and can be traced along the seismic section to the northeast where it underlies a belt of "post tectonic" plutons intruded into the Stikine terrane; the detachment zone appears to cut the Moho. To the west, the detachment zone has an apparent easterly dip and appears to cut, at a low angle, a zone of subhorizontal lower crustal reflectors. This zone of reflectors is in the region of the seismic section where an over 10 km thick high temperature (melt-present) top to the south thrust zone projects down the direction of thrusting to the vertical plane of the seismic section. Finally, further to the west, in a zone mapped along the eastern side of the Coast shear, the planar fabric produced by the thrusting has been folded around north plunging hinge lines. In the plane of the seismic section to which these hinges project, there are no major reflecting horizons above the Moho zone of reflectors; this would be expected if the folding were on a crustal scale. SC: TDE: 7245DE: 8110DE: 8115MN: Fall Meeting 1996