Print this pageABSTRACT: Development of the El Furrial Field, Eastern Venezuela
Maria Salazar
The El Furrial field is located on the northern flank of the Eastern Venezuela basin. Discovered in 1986, as of September 1989 it had produced 50 million bbl of 26°API oil from 17 wells with 1209 million bbl of estimated reserves.
The field is in an east-northeast-west-southwest-trending asymmetric anticline, which formed in a foreland setting bounded by reverse faults to the north and south and srike-slip faults east and west.
Sandstones of the Caratas Formation of Eocene age and Los Jabillos and Naricual formations of Oligocene age constitute the reservoirs. Thickness of these intervals is 793-854 m with 366 m of net oil sandstone.
The depth of the Naricual reservoirs is around 4116 m, with average porosity of 15%, permeability of 500 md, and water saturation of 20%. A 2000-m-thick sequence of Oligocene-Miocene shales constitutes an effective regional seal.
The main reservoirs correspond to the Naricual Formation which yields a high average rate of production per well: 6500 BOPD. The production mechanism is by rock and fluid expansion; initial pressure is 11,000 psi at reservoir depth, and the bubble point pressure is 6000 psi. Due to these factors, it is necessary to plan the implantation of a secondary recovery program for pressure maintenance. This program is scheduled for 1994; therefore, accelerated reservoir characterization is being done from core, PVT, DST, and RFT data. In this way fluviodeltaic and nearshore shallow marine environments have been defined for the reservoirs.
AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990