Induction Conductivity and Natural Gamma Logs at the Osage Skiatook Research Sites “A” and “B”, Northeastern, Oklahoma By Marvin M. Abbott, Bruce D. Smith, Robert A Zielinski, James K. Otton, and James J. Thordsen

17 wells 9 wells Number of wells logged

Skiatook Lake normal pool Surface and Subsurface Salty Area A-site

Well not near salt area Well near salt area Unit 3 Unit 2 Unit 4 25 Greater conductivity in the near surface section of all well logs Greater conductivity on the logs from wells near surface salt area Natural Gamma Ray correlated stratigraphic units across the area Natural Gamma Ray Identified lithologic changes within the units A depth of 25 feet was selected to test for a statistically significant difference between the near surface and deeper units conductivity values

CONDUCTIVITY, MS/M Grouped Box Plots of Borehole Conductivity Log Data 1. All sets are statistically significantly different for conductivity data grouped by depths 25 feet 2. Location, lithology, and proximity to salty areas have little affect on the significance of the difference between the data sets. 3. The change in conductivity data is probably associated with a natural depth of weathering for the region. LocationLithology Proximity to Salty Areas Depth

Borehole Geophysical Data and Surface DC-Resistivity Geophysical Data Aqueous Core-Extract Chemistry Data Water-Quality Chemistry Data

Location of 4 DC Resistivity Survey Points A-site

AA02 AA04 AA03 Conductivity Logs near DC Resistivity Survey Line Conductivity, mS/m

Borehole Geophysical Data and Surface DC-Resistivity Geophysical Data Aqueous Core-Extract Chemistry Data Water-Quality Chemistry Data

Example Log Core Extract Chloride <100 mg/L 25 Feet Core Extract Chloride >100 mg/L DC-07 Unit 3 Unit 4 100

PROFILE OF WELLS REMOVED FOR SURFACE SALT AREA

C C’ SOUTH NORTH PROFILE OF WELLS REMOVED FROM SURFACE SALT AREA DATUM 25 Feet Depth of Weathering Core Extract Data Sulfate is dominate anion species in shale and sandstone at 25 feet AA-11 has greater chloride values. Located at surface drainage from pit area but not in the surface salt area. 25 foot weathering zone intersects Unit 3, a sandstone section. Unit 3 Unit 2 Unit 4

PROFILE OF WELLS NEAR SURFACE SALT AREA

DD’ PROFILE OF WELLS NEAR SURFACE SALT AREA DATUM 25 Feet Depth of Weathering <25 Feet, Chloride Dominate Anion Species Chloride found at greater depths, where 25 foot weathering zone intersects Unit 3, sandstone section Unit 3 Unit 2 Unit 4

Water Quality Samples Total Dissolved Solids mg/L Core Extract Chloride <100 mg/L Core Extract Chloride >100 mg/L 25 Feet, 8 Meters Land Surface

Core Extract Chloride <100 mg/L Core Extract Chloride >100 mg/L 25 Feet, 8 Meters Water Quality Samples Total Dissolved Solids mg/L Land Surface

Summary Log conductivity values were greater near surface, <25 feet. Salt leachate can percolate through near-surface sandstone, shale, siltstone, and limestone. Borehole logs data are comparable with surface geophysics, aqueous core-extract methods, and water quality sampling. Core salt leachate was found at depths greater than the regional weathered zone 25 foot if permeable units were present near surface.

First Production …………….. ~1912 Production …………………… Gas Formation ………………… Bartlesville sand ( ft) Last drilling ……………… Skiatook Lake flooded ……… 1984 Last Production ……………… ~1984 Unplugged wells on lease ….. 4 Years of production …………. +70 Years since last activity …….. ~20 SALT PROBLEMS DO NOT GO AWAY A-Site Unit History and Information