3-D ANALYSIS OF THE SEDIMENTARY SYSTEM IN THE TAMBAREDJO FIELD, SURINAM
Israel Rivera Rabelo (Ph.D. Student)
Department of Applied Earth Sciences
Section Earth Sciences
The objective of this project is to extract the maximum amount of geological information from a unique
data set, which can be found in the Tambaredjo oil field Surinam. Particular reservoir characteristics and
high-resolution seismic survey offer the possibility studying 3D the relationship between the geometry and
intrinsic properties of the system, but also to quantify other properties of the various geological bodies
using a variety of algorithmic approaches such as geo-statistical and object oriented geological models.
Introduction
The Tambaredjo field is an oil-producing field (12.500 barrels per day) and is operated by Staatsolie
Maatschappij Suriname N. V. The oil comes from unconsolidated Paleocene fluvial and perhaps
transitional coastal marine deposits at an average of depth of 350 m. A very high data density from well
logs (in 2 developed areas) and from the seismic survey provides unique data sets that contain a large
scale and rarely encountered amount of geological information.
Results in 2002
In the year 2002 the 3D seismic dataset was acquired and loaded into a Geoframe 3.8 Project. The
interpretation process of the High Resolution Seismic (HRS) data started with 2D manual/visual analysis
of the seismic traces. They were identified and “picked” two horizons, the first corresponding to a very
clear unconformity believed to be caused by contrast in acoustic impedance at the boundary of the top seal
and calcareous layer (Hard Bank) and second was “picked” the Top Cretaceous unconformity.
The reservoir was found in between these horizons. A number of wells and logs had been loaded, but the
necessary velocity model for time to depth conversion was not yet implemented. Nevertheless we can use
these two points as top and bottom of the study interval.
With the purpose of understanding the seismic response of different lithologies from the Tambaredjo oil
field a forward model using finite differences algorithm to evaluate geological objects in acoustic terms
was created. The purpose was to understand the subsurface geology and to find the link between acoustic
and geological objects.
A basic geostatistical analysis of a small subset of wells, in order to find a relationship between the
production and the thickness of the geological facies present in the borehole, was done. For this analysis
we concluded that mapping of coal layers through the reservoir interval is going to give us valuable
information for mapping sand layers.
In order to look for new insights we moved from 2D to 3D visualization and interpretation. 3D
visualization is possible to achieve on a flat screen using the above-mentioned Geoquest software, but also
the SEG-Y files were converted into a multidimensional data matrix. The matrix had been processed and
visualized using Matlab specifically developed routines.
We are also collaborating with Vrije Universiteit and Stichting Academische Rekencentrum Amsterdam
(SARA), and we started visualizing parts of the Tambaredjo Dataset in the virtual reality CAVE at SARA.
An example of the virtual reality image can be seen in figure # 1. Here some geological objects (channels
and faults) were identified inside the reservoir interval. Studying the patterns, properties and geometrical
shape of the identified bodies, we can understand more about the sedimentological processes that took
place in the field and try to differentiate between sand, shale, and other lithologies from seismic traces.
a)
b)
Figure 1: Geological bodies in the reservoir interval: a) fluvial channel fill b) likely pivotal fault.
Research plan for the upcoming year 2003
Because of the new insights that the 3D visualization brought us, the plan for the year 2003 is to continue
this analysis and develop algorithms for object identification in 3D seismic. We also plan to design an
object oriented model and a geostatistical model for the recognition of the patterns and their links to
geological bodies.
Completed courses in 2002
 Geological outcrop analysis
 Seismic interpretation
Teaching Task
 Production Geology Practical –Teaching assistant (1 week)- Anton de Kom University Paramaribo,
Suriname.
Supervised M.Sc. Thesis
Haverkamp, H.; A seismic attribute analysis on the Tambaredjo oil field (completed in January 2003).
Schram de Jong, A.C.; Geological interpretation of the T1 sands in the Tambaredjo Field, Surinam
(ongoing).