Productivity stimulation of depleted reservoirs by applying new technologies to open the productive layers.
Ioana Vlasin, Dan-Paul Ştefănescu, Florinel Şuţoiu
Vol. 34, no. 2 (2017), s. 569-575, 
The greatest natural gas fields belonging to Romgaz company are characterized by an advanced stage of exploitation, which actually involves a special approach, from the perspective of the works performed in the wells. As part of the most recently Romgaz strategy, for these fields have been created new geological models based on 3D seismic acquisitions, which allowed identifying some new less drained or even undrained zones. This aspect created the premises for developing the opportunities for capitalization of the new reserves volumes, by applying the advanced technologies of opening productive layers by perforation and reperforation operations with deep penetration guns, using also underbalance conditions. We mention also that new cased hole geophysical methods like PNN and RCI consisted also important elements in establishing the perforation intervals and identifying the by-passed layers. The paper contains some relevant case studies, which illustrates the efficiency of these new methods.