Goshtasb Cheraghian - Islamic Azad University, Omidieh Branch, Young Researchers Club, Omidieh, Iran MSc. Petroleum Engineering
Sajad Tardasti - Islamic Azad University, Omidieh Branch, Young Researchers Club, Omidieh, Iran BSc. Petroleum Engineering
Mahboubeh Naderinasab - MashhadUniversity of Medical Sciences,Microbiology Research center,Khorasan razavi,Iran Associate Professor of Microbiology

One of the uses of biotechnology is the beneficiary of Microorganisms in petroleum industries. Biotechnology – in petroleum industry – has variousapplications which the use of Microbes (MEOR) in order to increase the exploit of petroleum is one of the most important one we can mention. Byproducing Alic Acids such as Lactic, Citric, Formic and Propionic Acids and also CO2, the microorganisms decreases the amount of pH and meltspieces of Carbonate minerals. This process leads to the increase of penetrability in the tanks. In this experiment the effect of specificmicroorganisms were used for assessing the porosity. Two selectedsamples of reservoir formation and cap rock were exploited then were soddened with the API 15 petroleum, Carbon sources and Nitrogen. Four Types of cultures - E.Coli, Pseudomonasaeroginosa, Bacilluscereus,Pruteus mirabilis - were produced in specific time and heat and also afterthe experiment the remaining amounts of samples will be measured.According to the decrease in the mass of the samples after the experiment, specially the one containing the Bacilluscereus, we can use them toincrease the microscopy and macroscopy porosity of the petroleum and gas tanks. In cap rock samples the increase of the mass is the outcome of the creation of the bulked cellsu, biosurfactant and the stocked particles in the leach which is the most important fact among the other two.

MEOR, porosity, formations, reservoir, cap rock