Relocated hypocenters in the NMSZ and parameters of modeled planes

The intraplate New Madrid Seismic Zone (NMSZ) is located in the northern Mississippi Embayment and over 200 earthquakes are recorded every year. We relocated 4131 hypocenters for earthquakes occurring between 2000 and 2019 using the HypoDD SVD relocation technique. The input catalog data are broadband data obtained from the Center for Earthquake Research and Information (CERI) earthquake catalog. We used earthquakes recorded from Jan 1st, 2000 to Dec 31st, 2019 within an area from 35.5 𝑁 to 36.9 𝑁 and from 90.6 𝑊 to 89.2 𝑊. This dataset includes 4568 earthquakes recorded by 314 stations.

A detailed description of the format of svd.reloc file is presented in Waldhauser (2001), USGS Open File Report 01-113.

Folders 'NP', 'RFP', and 'AFP' contain the OADC analysis simulation results for the northern part, Reelfoot fault part, and axial fault part of NMSZ respectively. Text files are log files of simulations that failed to converge. '.mat' files are binary MATLAB files that store the workspace variables of successfully converged simulations.

The NMSZ_31_fault_planes.parameters file contains the parameters of the resulted 31 fault planes from our research. Measurements of X, Y, and Z in this file are the distances from the origin located at 36.5 𝑁, 90 𝑊 in kilometers.

More details can be found in:

Zhang, Y., Fadugba, O., Powell, C., Horton, S., & Langston, C. A. (2022). A New Madrid Seismic Zone fault system model from relative event locations and application of Optimal Anisotropic Dynamic Clustering. Journal of Geophysical Research: Solid Earth, 127, e2022JB024194. https://doi.org/10.1029/2022JB024194