Petrocedeño block, located in the Junin Area of the Orinoco Heavy Oil Belt, is composed of the Main and South areas, and it has been drilled by more than 660 horizontal wells in a fluvial-deltaic environment using real time monitoring, and taking into account the response of gamma ray and resistivity logs and the structure of the seismic reflectors. The Main Area is about 324 Km2 and is covered by 3D seismic acquired in 1998 with a bin size of 15 m x 15 m, a nominal fold of 20 and a vertical resolution of 15 m.

Although the two drilling campaigns has been successful, every day the challenge to identify and to drill new targets is bigger, even with the incorporation of new technologies such as azimutal resistivity tools because the sand bodies are thinner, lateral facies variations are found more often and collision problems has increased. For those matters the improvement of the pre-existing seismic data with a reprocessing in the Main Area and the design of a new seismic in the South Area became a necessity. With the aim of drilling around 200 wells in the South Area, it was performed in 2011 the acquisition of a 3D3C seismic survey of 91 Km2, the first industrial 3D3C in the Orinoco Heavy Oil Belt, with the following characteristics: the use of DSUs, a record length of 8 seconds, a bin size of 10 m x 10 m and a nominal fold of 66. Parameters and characteristics were optimized from previous 3D3C pilots to improve the quality but also to perform elastic inversions from PP and PS seismic waves to better understand the subsurface and to get a reliable reservoir characterization.

A PP seismic Fast Track has been produced and has been used to start the delineation (vertical and slanted stratigraphic wells) and the development programs of the South Area, thus proving immediately its added value for Petrocedeño.

The lessons learned during the seismic design and acquisition will be useful to the future acquisitions in the Orinoco Heavy Oil Belt.

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