y-gRaph: An OpenOffice application to reconstruct paleostress fields from striated faults

y-gRaph, a user-friendly spreadsheet for reconstructing paleostress fields by means of the y–R diagram is presented. The y–R diagram is based on Bott׳s equation and translates the parameters of the stress ellipsoid to a XY plot representing the maximum horizontal stress orientation (σy) and the stress ratio (R), compatible with a given set of striated faults. In cases where several stress tensors fit the dataset, y-R diagram aids in visualizing unrealistic solutions or changes in the stress field with time. Furthermore, the spreadsheet allows to rotate planes and lines, thus simplifying the work with tilted fault populations. Histograms and rose diagrams showing the strike of faults and the trend of striae complement the y-gRaph main output. The application was built using Apache OpenOffice software and supports a variety of input data formats: (i) strike, dip and dip direction (SDD), (ii) azimuth and dip (AD) according to the “Right-hand rule”, and (iii) dip and dip direction (DD).