ABSTRACT: Three-Dimensional Reservoir Geological Modeling of the Cano Limon Field, Colombia

M. C. Budding, S. S. Flint, A. H. M. Paardekam, O. R. F. Dubrule

The Cano Limon field is located in Colombia, and had a STOIP of 2 bbl. A three-dimensional geological reservoir model has been constructed with the computer program MONARCH, on the basis of data from 24 wells. The model includes the high net/gross fluvio-deltaic M1 reservoir, and the overlying C5 reservoir, which consists of an undeveloped low net/gross coastal plain sequence. The modeling project was restricted to an area of 9 × 3 km.

The Cano Limon model is represented by a matrix of 1.75 million volume elements ("voxels") each measuring 50 × 50 m horizontally and 0.6 m vertically. At each voxel, the model indicates whether shale or sand is present. If sand is present, MONARCH differentiates between three types of genetic sand body types: channel, mouth bars, and crevasse splays. Correlatable sands are mapped using a deterministic approach, and the lateral extent of noncorrelatable sand bodies is derived using statistical distributions of width/thickness ratios. These distributions are directly derived from the information given by Cano Limon well data about the degree of correlativity of the sand bodies.

MONARCH combines structural information, as derived from seismic, with information about sand body orientation, as provided by dipmeter data, oriented cores, and seismic amplitude maps. In the case of Cano Limon, which is produced by a strong natural water drive with an unfavorable mobility ratio of 11, this level of integration helps provide reliable guidelines regarding the development of the field.

Although the upper C5 reservoir is yet undeveloped, the 24 production wells can hypothetically be "completed" in the MONARCH models. Calculations indicate that 60% of the total oil-bearing reservoir volume in the C5 reservoir is connected to 23 of the 24 wells.

MONARCH allows the geologist to input as much geological knowledge as is appropriate in the three-dimensional reservoir model. Therefore, MONARCH has application in a wide range of clastic reservoir environments, and can provide direct operational help to optimize reservoir development.

AAPG Search and Discovery Article #91003©1990 AAPG Annual Convention, San Francisco, California, June 3-6, 1990