Shallow seismicity and the classification of structures in the Lau back-arc basin

We compared Centroid Moment Tensors (CMTs), calculated for large (Mw >5), shallow (<30 km) seismic events to the orientations of seafloor lineaments (n = 4000) mapped throughout the Lau Basin, in the SW Pacific. Ship-based multibeam was combined with vertical gravity gradient data to provide comprehensive coverage to create the lineament map. By comparing the possible focal planes of the CMTs to the orientations of the lineaments, the most likely fault plane solutions were selected, thus classifying the faults and establishing the nature of the highly variable stress regimes in the basin. We resolved the strike, dip and dip direction of 308 faults, and classified 258 additional structures by fault type. The majority of the table was data downloaded from the Global Centroid Moment Tensor (GCMT) database (www.globalcmt.org: accessed October 2018). For more details about the column headers consult the GCMT database website. New data from this study include the latitude and longitude error estimates (in meters), the classified faults (column: 'fault_type'), and the stress domain (column: 'stress_domain'), allocated to each of the classified faults.