The USGS maintains a pool of SmartSolo seismometers for deployment primarily in the central and eastern United States. In 2022, with the help of University of Memphis students, two arrays consisting of 60 and 64 three-component SmartSolo seismometers were deployed in July/August and Sept/Oct, respectively, on east-west transects across the upper Mississippi Embayment. The earlier array is 18-km long with a sample rate of 500 samples per second. The later array is 287-km long with a sample rate of 250 samples per second. Data from these arrays is expected to improve our understanding of earthquake ground motions, Earth structure, seismic velocity and attenuation, and earthquake source properties.