UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY GEOCHEMICAL ANALYSIS OF POTASH MINE SEEP OILS, COLLAPSED BRECCIA PIPE OIL SHOWS AND SELECTED CRUDE OILS, EDDY COUNTY, NEW MEXICO Geocheraical Analysis of Mine Seep Oils, Collapsed Breccia Pipe Oil

ABSTRACT Oil shows, in the form of oil stains and bleeding oil, in core samples from two breccia pipes, Hills A and C, Eddy County, New Mexico, and seepage oils in a potash mine near Hill C breccia pipe are geochemically similar. The geochemical similarities strongly suggest that they belong to the same family of oils and were derived from similar sources. The oils are relatively high in sulfur (0.89 to 1.23 percent), rich in hydrocarbons (average 82 percent), relatively high in saturated hydrocarbon/aromatic hydrocarbon ratios (average 2.9) f and based on analysis of seep oils alone, have a low API gravity (average 19.4 ). The oils are for the most part severely biodegraded as attested by the loss of n-paraffin molecules. Geochemical comparison of seven crude oils collected in the vicinity of the breccia pipes indicates that the Yates oils are the likely source of the above family of oils. Six barrels of crude oil that were dumped into a potash exploration borehole near Hill C breccia pipe, to release stuck casing, are considered an unlikely source of the breccia pipe and mine seep oils. Volumetric and hydrodynamic constraints make it highly improbable that such a small volume of "dumped" oil could migrate over distances ranging from about 600 feet to 2.5 miles to the sites of the oil shows