Integrated Study for the Characterization and Development of the MFB-53 Reservoir, North Hamaca-Orinoco Belt, Venezuela
Authors: de Mirabal M. , Gordillo R. , Fuenmayor M. , Rojas G. , Rodriguez H. , Sanchez R. 
Published: December 2007

Integrated Study for the Characterization and Development of the MFB-53 Reservoir, North Hamaca-Orinoco Belt, Venezuela.

The purpose of this paper is to report the most relevant technical results obtained from a research and development study of Corpoven's MFB-53 extra-heavy crude oil reservoir, located in the Bare block - North Hamaca Area of the Orinoco Belt in Eastern Venezuela. This study was conducted by a Corpoven-Intevep multidisciplinary team with the support of national and international research centers in the development of a 3D numerical simulation model.

Foamy Hamaca crude oil behavior modelling has permitted the understanding of the high productivity shown by horizontal wells, which might lead to a primary recovery factor greater than 10% without compaction and/or steaming.

An increase of 30% in oil reserves was possible due to the results obtained from the numerical simulation performed by the Corpoven-Intevep team, allowing the total recovery factor to be raised from 10% to 14%. The same results may be applied to other Orinoco Belt areas.

Moreover, a geomechanical model was developed for this reservoir using laboratory tests. Consequently, optimum drilling and production strategies for both horizontal and vertical wells in the Hamaca Area were determined.

An optimum exploitation scheme has been defined with the use of the 3D model. A pre-defined cold production and larger spacing is anticipated prior to beginning with secondary recovery processes (gas injection and/or thermal activity), leading to a 30% cutback in the overall project cost.

Introduction

In 1994, an integrated study of the MFB-53 Reservoir was initiated. The reservoir has an extension of 165 km2 and an original oil in place (OOIP) of 1943 MMBLS. The largest extra-heavy crude oil recoverable reserves (194, MMBLS) discovered in North Hamaca belong to this reservoir.

Reservoir exploitation began in 1982, as of March 1996, 164 wells have been drilled (45 horizontal and 119 vertical), with an accumulated production of 71 MMBLS (3.6% of OOIP). Reservoir performance has been improved through the use of horizontal wells with an initial production of up to 3000 B/D and an average production of 1500 B/D. Reservoir pressure has decreased only 200 psia from an original pressure of 1220 psia (Table 1).

Due to the high productivity index (7 to 12) of horizontal wells, high volume lifting equipment was required in order to handle the produced fluids. Electric submersible pumps have been used successfully, and 62 MBD of the reservoir production are tied to this lifting method.

It is important to mention that Corpoven's heavy/extra heavy oil production forecast is 270 MBD for the year 2005, more than double the current production of 125 MBD. The development of the 3D model backs up the growing potential of Corpoven's expansion program. The main objective of this study was the design of an optimum exploitation scheme for the short-, medium- and long-term plans through a multidisciplinary team formed by Corpoven, Intevep and national and international research centers (Fig. 1).

Scope

The integrated study of the MFB-53 reservoir began in July 1994 under a multidisciplinary team with a technical proposal. To reach the objective, a fastrack in geology and reservoir engineering was implemented, applying novel technologies for the definition and construction of the geological model, seismic interpretation, research lab work on the special behavior of reservoir fluids, and finally the development of a three dimensional dynamic simulation model.

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