Red Top Program - Noble Waterflood Project
Ellsworth County, Kansas
Simpson Sand Reservoir

Background:   Pangaea performed a K-Series gas-sieve light hydrocarbon soil vapor geochemistry survey at the Noble Waterflood for J. J. Darrah, Jr., a Wichita, Kansas operator in the fall of 1998. The study was repeated and expanded in 1999.  The purpose of the survey was to identify the location of oil that had been by-passed by primary and secondary recovery methods.

Geology and Field Information:  The Noble Unit produces from the Simpson Sand that pinches out updip on an Arbuckle structure west of the field.  Dry holes define the feather edge of the sand along only part of the field and the geochemical survey was performed to define the remainder.  A reservoir pressure of 2000 PSI, created by water input, existed north of NO-36 and NO-30 (Map 1) during the 1998 sampling. This pressure significantly exceeds virgin pressure.  The south portions of the waterflood, south of NO-36 and NO-30 stood at 300 PSI during the 1998 survey.

Gas-Sieve Data:  Map 2 is the computer analysis of the raw geochemistry data (ethane+propane+butane concentrations in ug/L). The data suggests that the best location to site a well in the northern waterflood occurs in the area of sample location NO-12. Another geochemical anomaly exists in the area of NO-35. A DOE BOAST II engineering study performed concurrently with the geochemical survey suggests that there are oil filled bins at both anomalies.

Drilling Results:  A well was later drilled between NO-209 and NO-207. This location had a geochemistry anomaly of 2000 ug/L - 3000 ug/L, well below the intense levels seen at NO-12 and N)-35. The well tested 5-10% oil cut and was plugged.  Closeology had prevailed in choosing this location as the operator chose to drill near an abandoned producer.

Additional Gas-Sieve Data – Edge Study:  Afterwards an edge study was conducted to determine how close the plugged JV#4 (west edge of the map) was to the geochemical anomaly.  Map 2-Simpson Sand Reservoir Edge Study suggests that the strong geochemistry anomaly is 262” from the JW#4. The JW#4, having been cored through the sand section, has 2’ of bleeding Simpson Sand. The well was never produced in the sand and was plugged after producing a few thousand barrels from the deeper Arbuckle Dolomite.  Following the geochemical “edge”survey, the well was re-entered, fraced and put on line as a Simpson Sand producer.  Prior to the frac the well swabbed no fluid.  It now produces about 8-10 barrels of water free oil as would be expected from a very thin, tight, up-dip waterflooded sand well.