Josip Sečen, DSc
Editor-in-Chief
"Nafta" journal

Message to the Readers

Recently, in our journal we have been discussing the dilemma on whether oil and gas were given to us as a gift or as a curse. Most recent events in USA triggered this issue once again.
On one hand, by discovering huge quantities of natural gas in non-conventional reservoirs and by discovering new exploitation methods, the country solved its partial energetic dependence on international hydrocarbon producers and has initiated the construction of gas distribution system.
On the other hand, at the same time, we are the witnesses of ecological disaster in the Gulf of Mexico; uncontrolled eruption on BP concession. Search for profit and operator's incautious behavior caused the biggest ecologic disaster ever that shall change in the long run the economy based mainly on tourism and fishery.

Along with numerous information from oil and gas industry, in this issue of our journal we are also publishing two papers.

The first one titled "Reservoir Monitoring and Performance Using Simbest II Black Oil Simulator for Middle East Reservoir Case Study" was prepared by authors from Saudi Arabia. They emphasize the need for using simulators for describing the processes which occur in reservoirs during exploitation and also for introducing the most efficient methods for oil recovery increase.

Dubravko Novosel is the author of second paper titled "Impact of Carbon Dioxide on Ivanić Oilfield in Tertiary Oil Recovery Phase". The paper elaborates the issue of carbon dioxide aggregate state change during its injection into a reservoir, from liquid to gas or overheated state. Author points out the difference between the data on carbon dioxide characteristics taken in laboratory conditions and the ones taken in conditions in an injection well. As measurements in wells are expensive and sometimes technically unacceptable, for defining CO2 properties in these conditions, several approximations were used along with various equations of state.