Abstract: Western half of the East Anatolian Fault Zone has been mapped for the first time. Its connection withthe Dead Sea Fault System has been confirmed. Types ,and senses of the movements along the East Anatolian Fault Zonesuggest northeasterly movement of the Arabian block rather than to the north.Some parts of the North Anatolian Fault Zone have been mapped. These maps show clearly the great earthquake danger presented by the North Anatolian Fault Zone.Southward tilting of the Menderes Massive has been documented. This tilting supports the view defending the activeuparching of the central part of the Menderes Massive.The presence of previously unknown active faults has been shown ,and the value of seismo-tectonic maps has oncemore pointed out in the light of these discoveries.