Laserfiche WebLink
major element and isotopic compositions between the fault and seep waters, many of <br />these shifrs are either very minor -- as in the case of some of the isotopic compositions -- <br />or seep water analyses lie within the range of fault values -- as in the case of sodium. <br />Furthermore, where there are multiple analyses from a single source, variations in <br />composition are sometimes evident. Therefore, the range of compositions must be <br />evaluated rather than the average values. <br />For either the Division or the operator to show whether the fault waters are the <br />source of the seep water, it is essential to explain at least the following variations in the <br />data, going from the faults to the seep: <br />1. a significant loss of bicarbonate and carbonate from the faults to the seep, <br />2. a significant gain in sulfate content between the faults and the seep, <br />3. a slight gain in calcium, <br />4. a slight gain in magnesium, <br />5. a slight gain in postassium, <br />6. a slight to nil gain in sodium, <br />7. a shift in14C from low to undetectable percent of modern carbon values to detectable <br />pmc values, <br />8. a shifr in'H tiom very low (0 to 0.97) tritium units to 1.97 t.u., <br />9. a shifr in pH from alkaline values (7.98 to 8.63) to acidic (6.79), <br />10. a significant shift from mixed S"C values (-2.7 to +10.7) to a very light value (- <br />12.9); <br />1. a possible shift from light SD values in the fault waters (-1 14 to -126) to a heavier SD <br />value (-1 I S per mil), <br />12. a possible shift in S'aO from light values (-15.9 to -16.3) to a slightly heavier value (- <br />15.6 per mil), <br />l3. a significant increase in TDS, <br />14. a slight drop in temperature. <br />Other observations, which seem less essential to explanation of the waters, are: <br />l5. "fhe N,:O,: ratios of the dissolved gases in all of the waters range from about about <br />4:l to 5:1 while the O~:Ar ranges from about 12:1 to 18:1. These deviate somewhat but <br />still compare favorably with the same ratios in atmospheric gases, which are about 3.7:1 <br />and 20:1, respectively. Combined, these may suggest a relationship to atmospheric gases, <br />or a combination with atmospheric gases, where atmospheric gases are a prominent <br />component. <br />16. The S"S values of the waters, being significantly heavy relative to marine sulfate, is <br />evidence that the sulfur has itself been derived from an area where partial sulfate <br />reduction has occurred, probably in a relatively closed reservoir, thus enriching [he <br />residual sulfate in the reservoir in the heavy isotope. Oxidation of methane in a pyritic <br />bed could explain the source of the sulfur in these waters. <br />17. The 4"C values between CH, and CO, in the dissolved gases give equilibrium <br />temperatures as follows: 200 degrees C for the Rollins sandstone (assuming the reported <br />CO, value is -10.81 rather than +10.81); between 120 and 210 degrees C for the faults; <br />2 <br />