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We report hypocenters and focal mechanisms of microearthquakes located by an ocean bottom seismic network deployed in the median valley of the Mid‐Atlantic Ridge near 23°N during a 3 week period in early 1982. The network consisted of seven ocean‐bottom hydrophones and three three‐component ocean bottom seismometers. The instrument coordinates were acoustically determined to within 25 m at the 1 standard deviation level of confidence. The hypocentral parameters of the 26 largest microearthquakes are reported; 18 of these events have epicenters arid focal depths which are resolvable to within ±1 km formal error at the 95% confidence level. Microearthquakes occur beneath the inner floor of the median valley and have focal depths generally between 5 and 8 km beneath the seafloor. Composite fault plane solutions for two spatially related groups of microearthquakes beneath the inner floor …