GeoMechanics Technologies proposes to investigate the use of advanced percussion fracturing technology to stimulate and enhance permeability in hot rock for EGS development without large volume water usage-We will perform this Phase I investigation by executing the following work plan: (1) Building and expanding on our own and othersÂ’ past theoretical work to develop analytical descriptions of stress wave propagation induced by dynamic shear and compression loading at the bottom of a borehole- Develop and describe dynamic fracturing processes induced by shear, compression and tensile waves; (2) Develop and document numerical simulation of the percussion fracturing process, including dynamic stress wave propagation, fracture creation and fracture extension- Apply numerical modeling to consider alternative wellbore shear and compression loading scenarios and fracture extent for alternative rock properties; (3) Fabricate a laboratory system to test and demonstrate percussion fracturing in core samples- The system would include control and monitoring of axial stress and radial stress- It would also include a controlled percussion drilling motor and impact rod system; (4) Apply the laboratory apparatus to investigate percussion fracturing on rock samples under a variety of differential stress conditions; and (5) Comparing laboratory observations with numerical model results, providing confidence and validation to subsequently use numerical simulation modeling at the field scale-