This Phase I SBIR project proposes a field adaptation and evaluation of a prototype in situ geotechnical testing system for earthquake resistance. The system is to provide reliable estimates for soil deposits of the in situ cyclic shear vs strain characteristics needed by dynamic earthquake analyses such as liquefaction, cyclic degradation and deformation, and undegraded nonlinear inelastic characteristics. Problems to be addressed include reliably predicting amplified motions, liquefaction, and deformations of soil deposits - sources of significant seismic loss. While this area has been advanced considerably, fundamental improvements in estimating soil characteristics are still greatly needed. Earthquake-like cyclic loads are to be applied. Tests, however, are to be conducted in situ with many steps to preserve in situ conditions. Recent laboratory prototype tests show promise in the proposed approach and the potential is good to apply it to retrofitting of existing critical constructed facilities for earthquake resistance and in land use planning for seismically active areas.