The Trattnach oil field is located in the Upper Austria Molasse basin. The Cenomanian sand is the main reservoir in this field where the 10 producing wells were drilled. Primary depletion drive production began in 1975 with well (Tratt-01), until 31st Dec.2007, over 1.08 million cubic meters of water were injected into 2 injector wells within the project area, while 367.12 thousand cubic meters of oil were produced. In addition, a total of 2.09 million standard cubic meters of gas was produced and a cumulative of 1682 thousand cubic meters of produced water of 82% WC was produced. Thus, the objective of this research is to utilize an interpreted geological model of the Trattnach oil field to construct a field scale reservoir simulation model in a commercial package and compare the results with the ones obtained from an alternative simulator using unstructured grids in order to generate development options which improve recovery. I have built a full black oil simulation model using the detailed geologic characterization of the Trattnach reservoir to resemble the flow and the large variation in reservoir properties. A 32-year history match was performed to calibrate this model. Several sensitivity runs were made to prepare the model to predict future reservoir performance. During this work I found that the data available for the reservoir is rather complicated as there is usually an enormous variation in reservoir properties in the static model especially in permeability. It was around the area of the wells about 1mD, which obliged me to make some permeability changes around this area to calibrate the model. In addition, the SCAL data available are challenging to represent the reservoir since there are only 5 samples taken from Cenomanian 3 layer to be used in the simulator. Moreover, a high WC values at the beginning of the simulation period due to a high draw-down caused by some relatively high rate wells. For all that, many realistic changes were made for the model to obtain a proper history match. Eventually, several simulation runs applying the above mentioned changes revealed an appropriate match in field pressure and oil rates; however, the WC was matched to some extant properly. According to the results, a just-right WC match was hard for me to reach; therefore, the possibility of refining the model was highly recommended to clearly highlight the embedded shale layers might cause that severe heterogeneity which might prevented the model from being fittingly matched.
|Translated title of the contribution||Lagerstättensimulation des Ölfeldes Trattnach unter Verwendung der Software ECLIPSE100|
|Award date||18 Dec 2009|
|Publication status||Published - 2009|
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