The analysis of the geometry of distribution of earthquake foci occurring in the continental South American plate above the subducted Nazca plate reveals that in the region of Ecuador these earthquakes accumulate in 8 well-separated fracture zones. These zones are interpreted as a system of deep seismically active fractures induced in the continental plate by the process of subduction. It is shown that the position of known thermal springs and of observed hydrothermal alterations in Ecuador correlates with the outcrops of the fracture zones.