Publications

The GST (Mark of Schlumberger) is a relatively new tool which records and analyses- the gamma-ray spectra induced by neutron interactions with the formation. A brief introduction to tool principles and capabilities will be given first. Then, actual operating experience and the limitations noted in two producing fieIds of the Mahakam delta will be presented. These actual field cases demonstrate the way reliable information on fluid content may be obtained in front of depleted reservoirs.The examples given demonstrate how changes in fluid levels can be monitored and the corresponding residual oil saturation determined.The fact that this fluid identification can be performed immediately on the rig site, leading to a confident selection of zones to be completed/recompleted, is of particular interest during workovers.