Partial reorientation of the deformational structures at Site 735 using paleodeclination measurements

Abstract

Proposes reorientation of the deformational structures at Site 735 relative to one another, and to the remanent magnetic vector. This reorientation is based on the assumption that the in-situ stable remanent magnetic vector (SRMV) of each core piece pointed in the same direction before drilling. The consistency of the results supports this assumption. The dominant dip azimuth of the earliest deformation structures (magmatic foliation and some granulite-facies, solid-state foliations) is northwest of the SRMV. These structures tend to make a 45° angle with the latter solid-state shear zones. The dominant dip azimuth of these shear zones is west of the SRMV, and the stretching lineation is downdip. The true orientation of these structures in the geographic framework is not known because the in-situ azimuth (declination) of the SRMV is still undetermined. -Authors