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Microbial exploration technology
Microbial Exploration Technology (MET), also called microbial enhanced oil recovery (MEOR), is a method of enhanced oil recovery (EOR) that identifies microorganism levels in soil near reservoir surfaces to estimate hydrocarbon levels. This method is largely based on the premise that the more microorganisms present, the more hydrocarbons are present for those microorganisms to feed on.
Hydrocarbon degrading bacteria can be used to detect migrating hydrocarbon gases from oil and gas deposits. As short chain hydrocarbon gases migrate to the surface, bacterial cells metabolize these gases in the near surface aerobic zone. In the laboratory, EBT measures the response from these hydrocarbon utilizing bacteria and develops their recommendations based on a proprietary data analysis process. This process has been used to survey over 4.3 million acres in North America, South America, and Europe, with over 3.7 million of these acres in Canada, primarily in south eastern Saskatchewan.
Microbial Exploration Technology (MET) is based on three physical and biological principles.
First, this technology assumes that oil and gas reservoirs will have a certain amount of hydrocarbon gas that migrates vertically to the surface. Second, these gaseous hydrocarbons serve as a nutrient source to soil microorganisms in the near surface aerobic zone. Finally, once an oil or gas reservoir undergoes production, the near-surface MET signal over the produced area of the reservoir decreases; gas then migrates more easily through the wellbore than the overburden. In the laboratory, these microbes are extracted from the soil, the response to short chain hydrocarbons is measured, and a series of contour and numerical maps is created based on the statistical analysis of the raw data.
It has been determined that tile non-recommended sites have, on average, had lower cumulative production than those sites that were recommended. 
It has been shown that microbial surveys show a positive correlation between microbial highs and hydrocarbon deposits.  This is especially apparent in the Elcott fll-2 Rl-3 W2), Bowdoin (Tl-2 R12-14 W3), and Flinton (TII R6-7 W2) areas where post survey drilling has confirmed the microbial response. Exploratory wells drilled on microbial highs had a 63% success rate in the Elcott survey. The Flinton survey area had an 76% success rate. Overall, exploratory wells drilled on microbial highs have been compIeted 25 of 32 times, for a 78% success rate.
Statistical analysis of the soils includes an average MET value, relative average, percentile rank, and a Percent Probability of Success (%PS) rating. The %PS rating is a proprietary analysis that is based on the correlation of MET surveys with over 640 wells in the surveyed acreage. Use of MET in the oil and gas industry can increase productivity of petroleum reservoirs and save time that would be wasted with EOR on dry wells. Overall, the method can be an efficient and economically viable method of EOR.
- Munnecke, D.M., Weaver, W.P. 1999. Microbial Surface Geochemical Exploration Technology. Presented at the Technical Meeting/Petroleum Conference of The South Saskatchewan Section, Regina, Saskatchewan, Canada, October 18 - 21. PETSOC-99-100. http://dx.doi.org/10.2118/99-100.
- Munnecke, J. 2014. Geomicrobial survey results follow drilling success. Oil & Gas Journal 112 (12): 56—60. www.ogj.com/articles/print/volume-112/issue-12/exploration-development/geomicrobial-survey-results-follow-drilling-success.html.
Noteworthy papers in OnePetro
Jackson, S.C., Alsop, A.W, Choban, E.R., et al. 2010. Microbial EOR: Critical Aspects Learned From the Lab. Presented at the SPE Improved Oil Recovery Symposium, Tulsa, 24-28 April SPE-129657-MS. http://dx.doi.org/10.2118/129657-MS.
Kotlar, H.K., Brakstad, O.G., and Markussen, S. 2007. Use of Microbial DNA Probes as a Potential New Tool in Oil Exploration and Characterization. Presented at the International Symposium on Oilfield Chemistry, Houston, 28 February-2 March. SPE-106418-MS. http://dx.doi.org/10.2118/106418-MS.
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