D25 IOR AND EOR – CHANCES FOR INCREASE OF OIL PRODUCTION AND RECOVERIES IN EXISTING MATURE RESERVOIRS Abstract 1 After the application of conventional oil extraction techniques about 2/3 of discovered reserves still remain to be produced. In view of high probability for oil presence and oil price increases investments in research of possibilities for higher recoveries and higher production with application of appropriate IOR and EOR methods are justified naturally under economic conditions. Introduction Let us assume the position of owner or at least oil company director whose main task is renewal of reserves and whose business success is