THE 1986-89 JOĂO CAMARA EARTHQUAKE SEQUENCE - SEISMICITY AND ITS INTERPRETATION

Shallow seismicity along a well-defined section of reactivated Precambrian basement near Joao Camara, Brazil (5.5'S, 33.7'W) has continued since August 1986. Deployment of temporary local stations has ensured that this sequence is by far the best recorded in Brazil. Several thousand events have been recorded above magnitude 0, and activity was still been recorded in June 1989. Damage to property in the largest event was extensive in and around Joao Camara. Epicenters define a 25 km linear pattern of seismicity northeasterly strike. A composite faut plane solution shows dextral shear along this strike with a small normal component.