ABSTRACT:

The Ebro Delta area, offshore Northeast Spain, is one of the most important oil areas in the Mediterranean Sea. The basin has yielded approximately 230 million barrels. Several oil companies have made seven commercial discoveries since the first exploration well was drilled in 1968: Casablanca, Amposta, Dorada, Tarraco, Rodaballo, Boqueron and Chipiron fields. The first discovery in the basin was Amposta field, in 1970, which produced 55 million barrels of oil. The largest field is Casablanca, developed in the early eighties, which has a cumulative production of 140 million barrels, which is still producing via a fixed platform, pumping the product directly to the REPSOL-Y.P.F. refinery onshore. The Chipiron oilfield was discovered in summer 1999. Initial evaluation indicated the commercial marginality of this field. The development concept was clearly defined to be an 8.3 km subsea tieback to the Casablanca platform, however several technical challenges had to be resolved. The oil has high paraffin content with a WAT of 20°C, high H2S and CO2, and high temperature (175°C at reservoir).The subsea multiplexed electro-hydraulic control system was designed to control six wells in a distance of 20 km as other prospects were identified in the area that could be connected to the Chipiron manifold. The Control System manufacturer set an in-house record since the elapsed period from contract award to first SCM installation was just 8 months. The wells are flowing to the platform via a 5,5" ID insulated flexible pipeline trenched and buried. The trenching and burying work has also been a challenge as the highly cohesive clays of the area had made to fail all attempts to trench in the passed projects. First oil occurred in just 14 months from project sanction and less than 24 moths from wildcat.

This content is only available via PDF.
You can access this article if you purchase or spend a download.