The Gulf of California rift forms a geologically young and active plate boundary that links the San Andreas strike‐slip fault system in California to the oceanic spreading system of the East Pacific Rise. Although this is a classical example of a transform‐rift plate boundary, the tectonic evolution of the Gulf of California and surrounding regions is complex and poorly understood due to a lack of geological and geophysical data. In 2002, the Network of Autonomously Recording Seismographs(NARS)‐Baja network was installed.lt consists of 19 broadband seismic stations deployed in the Baja‐California and Sonora provinces of Mexico (Figure 1). Since NARS‐Baja surrounds the Gulf of California rift system, it is ideal for constraining earthquake faulting processes and the crust‐mantle structure of the region. Moreover, NARS‐Baja, in combination with permanent Mexican and U.S. arrays, forms a unique linear array in excess of 4000 km that should lend itself ideally to seismological studies of the North American‐Pacific plate boundary on a larger scale. NARS‐Baja is planned to operate for at least 5 years. To promote involvement from the entire research community the data collected from the stations will be made available immediately following routine data quality checks
