Old is Not Finished- Creaming Value from Legacy Seismic Datasets in Maturing Hydrocarbon, a Case Study of the Lemur Field Development

Abstract Leveraging on existing seismic dataset and merging different vintages together to help improve signal to noise ration and image fields that are straddled on different seismic datasets is key and essential for planning infill wells and near field exploration. A merge of three different seismic datasets was done to help better image the Lemur field. After the merge, an optimum velocity model was built, and migration carried out. This led to a better resolved broadband seismic image which is essential in understanding hydrocarbon fields and unlocking more reserves. For proper seismic interpretation to take place, clearly understanding the stratigraphic features to map, in this case, straddling across fields, is key to delivering the structural framework and thus delineating the reservoir architecture. This is tied to having good events continuity and true amplitudes in the seismic dataset. In this paper, reprocessing an already existing seismic dataset with recent technology (broadband processing) have shown more structural and stratigraphic features which were not clear in the legacy seismic of the Lemur field, onshore Niger Delta, Nigeria. The most impacting part of the workflow deployed in this work is the Merge of the different surveys, the broadband processing and accurately estimating the velocity used for migration. On the basis on this new seismic dataset, a new infill production well was drilled in the field with success.