MEERS MICROSEEP SURVEYS

MEERS MICROSEEP SURVEYS INC.

THE BENZENE, MAGNETIC, & CALCITE METHODS OF MICROSEEP DETECTION

Benzene, C6H6 is a heavy aromatic hydrocarbon found in oil. It is carried to the surface from oil reservoirs with other lighter hydrocarbons. The larger molecule has some permeability restrictions; however, the molecule is mostly 2 dimensional since it is a ring molecule. The ring property allows the molecule to pass through micro fractures that are found on and around hydrocarbon trapping structures. The larger ring molecule has a harder time passing through intergranular porosity that has been occluded with secondary mineral precipitation. Secondary mineral precipitation is seen in the microseep chimney above hydrocarbon reservoirs. Since the Benzene molecule has a hard time migrating through this chimney, it is diverted and found in higher concentrations around the edges of the chimney and reservoir. The Coriolis Effect adds to this microseep geometry known as a “Halo” type anomaly.

The concentration of hydrocarbons in the near surface soils causes a chemically reducing environment. Magnetism is destroyed by oxidation of magnetic minerals to nonmagnetic minerals. This is similar to rusting iron losing its magnetism. The presents of hydrocarbons inhibits oxidation of the minerals since the hydrocarbon is more readily available to accept the oxygen atom changing it to an alcohol leaving the magnetic mineral in its original chemical state. This interaction of the hydrocarbon and oxygen causes the secondary effect of high magnetism in the area of the microseep.

Hydrocarbons react with gypsum in the soils to cause precipitation of caliche. The formula shown below demonstrates this reaction.

CH4 + CaSO4 = CaCo3 + H2S + H2OMethane + Gypsum = Caliche + Hydrogen Sulfide gas + water

Caliche precipitation in the near surface depends on the presents of Gypsum. The area around and north of Abilene is where the Permian outcrops at the surface. These Permian beds were formed in the shallow seas of the Permian basin to the west. They have an abundance of evaporates such as gypsum. The presents of caliche in the Permian surface soils are a very good indicator of hydrocarbon microseepage. Many times the Caliche is seen in the microseep chimney over the reservoir. Caliche and

Phone (325) 665-5915226 Dug Out Mtn. Rd.Tuscola, Texas 79562E-mail – deeprock@aol.com

calcite is the porosity occluding mineral seen in the microseep chimney. Quantifying the caliche is done using X ray Fluorescence of the soil sample.

Blending the Benzene, Magnetic Susceptibility, and the XRF defined caliche shows the absolute microseep geometry that defines subsurface oil reservoirs.

Services are all inclusive from field gathering to the final maps and report. This insures quality control throughout the process.

The X Ray Fluorescence laboratory is in my office, insuring sample preparation is done with the proper technique. The laboratory is run by my partner, Pete Renick PHD. Pete is a geophysicist who originally worked for Gulf Research and led the team that developed 3D seismic. He has helped in developing the process we use for our microseep detection.  

The final maps and interpretation are all based on the combination of Benzene, direct hydrocarbon measurement, and Magnetic & XRF non-direct microseep detection. The blend of direct and non-direct detection helps eliminate noise levels seen in each

instrument. The soil samples taken from 24-36 inches below surface have very little surface oxidation or contamination.  I sample the prospect areas using a grid type system. This type of sampling will show microseep geometry. The geometry is extremely important because reservoirs will present themselves on the surface as either Apical or Halo. The grid pattern will show the microseep geometry as well as certain key elements seen on the XRF in the center of a Halo anomaly. The grid density depends on the target reservoir. If the target is channel sand, such as the Tannehill, a density of 440 ft. N-S, & E-W is used. Maximum grid spacing is 528 feet is used on large areas for cost conservation. I have used grids as small as 220 ft. looking for variation of porosity in pinnacle reefs.

Survey cost is $50 per station, or about $11 per acre on 440 ft. grid, or about $8 per acre on 528’ spacing. The cost is all inclusive with no additional charges, unless it is over 150 miles away from Abilene. Jobs further away requiring overnight stay would be charged for motel and fuel expenses.

Feel free to call with any questions or comments.

Monte MeersPresidentMeers Microseep Surveys Inc.deeprock@aol.com(325)665-5915