Volcanic activity in the Azores. Report for 1959–1964

During the period 1959 to 1964 recorded volcanic activity in the Azores islands (Atlantic Ocean) was manifested by fumarolic fields in S. Miguel, Terceira, Graciosa, Pico and Faial and by two submarine eruptions off Pico and S. Jorge. Fumarolic activity increased in the Faial Capelinhos vent (in eruption 1957–58) after December 1963; it is concluded that the phenomenon is related to the 1963 and 1964 eruptions in the S. Jorge Channel. During February 1964 an important seismic swarm of more than 500 earthquakes, with volcanic tremor, occurred in S. Jorge.