Microbial Exploration Technology Frequently Asked Questions: MET FAQ – Theory/Operations.
1. What does MET mean/stand for?
MET stands for Microbial Exploration Technology and is a surface geochemical exploration tool provided by Environmental BioTechnologies, Inc. to support exploration and exploitation activities in the oil and gas industry.
2. What is being measured?
EBT’s MET method measures the soil’s metabolic activity towards the metabolism of hydrocarbon gases, most specifically the higher alkanes; ethane, propane and butane.
3. Why is this detection method for hydrocarbon microseepages valid?
First, microbes in soils are generally in a starved condition due to minimal organic nutrients. Thus, since microbes can grow well on hydrocarbons in aerobic environments, they will respond very positively to hydrocarbon fluxes through the near surface environment. Our technology allows us to selectively enrich and identify those microbes present that are at elevated levels in the environment due to hydrocarbon flux from subsurface petroleum deposits.
4. Does soil type have an effect on the MET value?
We have followed MET results for over 15,000 soils that were classified into 15 soil types. While there was a difference we detected, we do not believe MET values are directly related to soil type. Please see the extended answer by clicking here.
5. Does soil pH have an effect on the MET value?
EBT has analyzed over 1,900 soil samples for both pH and MET value. The soils were collected in the southern portions of Alberta and Saskatchewan, Canada during the months of May through September, 1996. We see a general decline of MET value as pH increases. However, in any pH range, MET values can range from 0 to 40 thus we do not believe that soil pH is a strong influence on measured MET values. Click here for full details of this major survey.
6. Does soil moisture content have an effect on the MET value?
EBT has conducted a series of studies to determine if soil moisture has an effect on the MET score. The data indicates that soil moisture in the range of 10-28% has only a minimal influence on the MET value. As soils dry out and are below the 8% moisture content, we note a decreasing MET average. Depending on the survey, we may need to adjust our interpretation of a surveyed area based on soil moisture content.
7. Will near surface biogenic methane interfere with MET survey technology?
Yes it could if we did not carefully determine where to sample in the soil column to avoid surface contamination and if we did not develop a lab process that selects primarily for metabolism of C2-C5 alkanes that are not produced biogenically like methane can be.
8. How are the results reported?
Our laboratory analysis provides us with a value for each soil that ranges from 0 to 40. This MET value is an average of 4 determinations of a soil’s metabolic activity towards the metabolism of hydrocarbons. Starting with this value, we develop three other methods of data review and presentation, the Relative Average, the Percentile Rank and the % Probability of Success. A survey report will have this information presented in contour graphic form as well as in electronic copy.
9. Is vertical migration assumed?
We initially assume that vertical migration is occurring and that the horizontal offset is less than +/- 7%. So, for a deposit at 5000 ft., we would expect the “cone” for vertical migration for a specific point to be approximately 100 yds. radius. We also expect that the geologists working the area will be aware of potential fault or other subsurface structures that might cause an abnormal side slippage of the gas migration path.
10. In what areas have you completed surveys?
We have completed surveys in 11 countries around the world, both on and offshore. We have 3 million acres of survey coverage in Canada alone, with most of our surveys are in the Williston basin in Alberta, Saskatchewan, Manitoba and N. Dakota. We also have completed 10 surveys in Peru, both on and offshore. We have surveyed in the jungles of Ecuador, the high dry desert in Argentina, southern Texas, the Mediterranean area of Albania, the tundra of northern Canada, and several offshore locations in South America.
11. Who have you completed surveys for?
We developed this technology over a three year period through our collaboration with Vista Energy, Regina, Saskatchewan and introduced the MET process as a commercial service to the industry in 1997. Click here to see who we have worked with since 1997. (Client list link)
12. What difference does sampling density have on the results of the survey?
We prefer to sample an area on a ¼ by ¼ mile grid pattern, or 0.5 by 0.5 km if working in metric system. That is the most economical method to provide the type of results we feel are best suited to a client’s needs. If the area to be surveyed is large and an exploratory survey is desired, we recommend a mile by mile survey with samples collected every 1/4 mile. The grid pattern really depends on the size of the hydrocarbon deposit you expect to find. If you are looking for a meandering deposit 800 yd. wide, we need to use at least a ¼ by ¼ spacing pattern, while when looking for bigger deposits in the S. American jungles, we can open the grid pattern.
13. How do we operate in the field?
Basically, over good terrain, we can walk, drive a small truck or ATV and locate ourselves with GPS units. Samples are collected by digging using a small shovel. Samples are collected in air tight bags and sent to our California processing labs daily or weekly as needed. We gain permission from surface owners before crossing their land. In more difficult to reach areas, we have used helicopters and small boats to gain access to the survey area.
14. How is “background” response determined or accounted for?
Each survey area will have an inherent background MET level of response. This results from the type of reservoir present and the type of hydrocarbon charging the reservoir, the type of overburden, and the surface environment. EBT survey reports provides 7 different methods of data presentation, two of which were developed specifically to account for differences in inherent level of MET signal response for survey areas. Secondly, we can apply corrective measures for low soil moisture content or other known environmental conditions which impact MET signal response. Through our experience with over 4 million acres of survey work, we can also adjust the level used to indicate significant MET signal response when we report the project results.
15. Can the difference between oil and gas be determined?
We do not claim that we can determine if the signal we are measuring is coming from a gas or crude oil reservoir. What we do claim is that a strong MET signal in an area is indicative of petroleum hydrocarbons.
16. How do you know your method works?
We know the method works through statistical review of our data in comparison to drilling results. EBT has developed a database of over 640 wells that have been drilled in our surveyed area. For each drill site, we determine MET value for the nearest 4 sample points and determine how our MET survey relates to drilling results. Please look at our correlation of MET survey results to drilling results for supporting information. There is a direct correlation that higher MET values lead to higher drilling success. For exploratory drilling, we have been correct 80% of the time. We also have been fortunate to recommend well sites that have now been completed and we receive royalty on these wells.
17. What is the Percent Probability of Drilling Success?
We have a unique process where we can estimate the probability of drilling success for a location based on how the MET value for the area has corresponded to previous drilling results. We continually monitor the drilling activity by industry in the areas we have surveyed. When a well is reported, we determine the MET values for the four samples around the site. We now have over 700 wells in our database which allows us to develop a correlation of drilling success to MET survey values. Using this historical correlation, we can develop %PS contour maps that represent the expected probability of success for the surveyed areas. When we have recommended an exploratory well site based on MET data, 14 of 18 wells were completed (77%) while industry overall completed 41%.
18. How was the “probability of success” developed?
EBT developed the analytical approach based only on MET survey data and drilling results provided by the oil companies. Our analysis is based on cased and completed wells, NOT economical wells. We cannot easily follow whether a well is producing at economical rates.
19. Is the process proprietary?
Yes. Several other companies provide microbial based surface survey technologies but EBT’s process is different. The principles for all surface geochemical surface survey technologies rely on vertical migration of hydrocarbons and their detection at the near surface. What is unique to our process is how we detect this signal and how we process this data. We offer a unique data analysis to go along with a unique technology. See an
example of our survey maps which would be included in a report and a description of our % Probability of Drilling Success.
20. Why is “old oil” not detected?
You may notice in review of MET maps that we generally do not obtain high MET signal strength over older production. EBT is not the first or only surface survey company that reports this phenomenon. We believe what is occurring is that the natural pathway of vertical gas migration is distorted once a well is drilled into the reservoir. Now, gases have an easier pathway to the surface via the well than through the overburden and thus, the flux of hydrocarbon gases to the surface is reduced. Where the signal dissipates is in part related to how the field is being drained. In repeat surveys over an area recently brought onto production, we have seen the signal pattern affected by production within a 6 month period. Thus, wells on production for many years are expected to have a negative impact on the signal we measure. We normally assume that this areal impact can be 400 to 800 m from a well.
21. How do you know a lack of signal isn’t a dead area or a donut hole?
Our results do not support the older donut hole theory. We believe that early surface geochemists did not realize that production could reduce the surface signal they were detecting. And since they were always challenged to “see a current field as a test case”, their surveys tended to highlight the edge of the field, thus the donut effect; oil or gas in the middle and surface signal on the edges. We have data to disprove this hypothesis. Give us a call if you want to discuss it. When we do not have a MET signal (the well is located in the bottom quartile) the drill sites are completed 10 times less frequently than well sites located in our top quartile. You can’t obtain this kind of drill results using a donut theory.
22. How should MET surveys be used?
We can help you on that question, just give us a call. Our past clients have used our surveys to: 1) economically ($500,000) review a large block of land (126,700 acres); 2) correlate with 3 D seismic surveys ( MET surveys are 2% of 3D costs); 3) review land for posting at land sales; 4) select drill sites in conjunction with seismic; 5) gain broad understanding of a regional area; 6) rank potential drill sites; and 7) economically see why one company is interested in an area. We think MET surveys are very accurate, fast to conduct, can be easily run in restricted areas and provide very valuable support information. Once you have seen the type of results we can provide, we are sure you will find effective ways to reduce your exploration costs and improve your drilling success
23. What is included in a final report?
All our survey contracts include a full report. We will not only provide you with the various maps but we also will provide you with a technical interpretation.
24. How do the survey results compare to 3D seismic?
We all know that 3D seismic surveys can be extremely valuable to exploration and exploitation activities. What you may not realize is that MET surveys can be used in conjunction with 3D surveys. MET surveys cost around USD $3-5 per acre, depending upon terrain and sample density, so they can be used in advance of seismic to define areas of interest where 3 D should be run. Or MET surveys can be run concurrently and then you will have a physical and geochemical description of the area. Seismic says the
structure is there, MET says the hydrocarbons are there. We have run MET surveys where 3D surveys have been run. We can show you our results, unfortunately the oil companies won’t release their 3D results. But we can tell you where they elected to drill based on 3D and we can report their drilling success versus how the MET surveys would have supported drilling. This is quite impressive.
25. Why use microbes as a detector for hydrocarbon detection instead of just measuring the actual gases?
Well, we think it provides a much more accurate description of the surveyed area. Why? First, because it is an averaging event. If you go to the field and collect a sample for later measurement or directly measure the hydrocarbon level in the field, you get an instantaneous measurement. We know from the literature that soil gas composition changes throughout the day due to temperature changes, moisture content, barometric pressure, planetary positions, etc. Microbes are present in the soil as a result of millions of years of hydrocarbon microseepage. Yes, the MET signal will vary throughout the year, but percentage wise less than the variation of soil gases. Secondly, our process allows for optimization or enrichment of the signal we measure. In processes that use chemical detection of gases, the level of hydrocarbon decreases during analysis. There is no way to amplify the signal, it only gets smaller during the analysis process. Thus, their error bars get greater. In the MET process, our signal gets stronger during the analysis and thus our error bars should be smaller. Do other methods report this high rate of technical success? Only one other process, to our knowledge reports as high of success rate as we do and it is also an averaging method. Unfortunately, you need to install and leave the collector in the field and then return to collect and process. EBT’s process is significantly faster, does not require going back to a location in the field and is priced at 4 to 8 times less than the other technology.
26. What is the drilling success based on MET results?
We believe that our method will produce around 75% accuracy for exploratory wells. The wells included in our data base are primarily from Canada, with some from S. America. Even though our data interpretation is based on Canadian well results, we find for instance that all 14 wells in our Argentina and Ecuador subset have been correctly defined. We recommended 7 well sites and all were completed. We did not recommend the other 7 and all were abandoned.
27. What is the cost of MET surveys?
We will be happy to provide you with a fixed price contract for our MET survey services. For a general estimate, consider USD $3-5 per acre, depending upon terrain and sample density. A township size survey may cost around $90,000, please contact for current pricing and quotes. Want to conduct a dual survey along with 2 D seismic (highly recommended approach) consider $500 per linear km as a general cost.
28. How will I benefit from having a survey done?
We have provided some examples of surveys that our clients have supported. See how they have used our services. You will gain a better understanding of an area quicker, more economically, and more precisely than you can imagine.
29. What kind of expertise do the employees at EBT have?
EBT focuses on providing biotechnological based services to the oil and gas industry that’s why our people are skilled in this field. See who we are and give us a chance to perform for you.
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