Qualitative Slope Stability Evaluation for a Pipeline Route Off Espirito Santo State, SE Brazil

In order to select a pipeline route a geophysical, geological and geotechnical survey has been conducted at the continental slope off Espirito Santo state. The survey comprised an area of approximately 470 km² between the 60 m and 1.380 m isobath with a total of more than 5.700 km of geophysical data and 70 geological and geotechnical piston-cores. An integrated interpretation of the data showed the presence of several obstacles that should be avoided allowing the selection of an optimal route to the planned 12” export gas pipeline determining areas associated to erosional and depositional events. Moreover, a qualitative stability analysis showed that the area is stable under the actual geological conditions and that the instability features observed were generated during the pleistocene when the area was dominated by a shelf-edge delta associated to the Doce river.