Uranium ore-forming systems of the - Geoscience Australia

Uranium ore-forming systems of the Lake Frome region4.2.1 Datasets for the Lake Frome regionDespite the size of the PIRSA dataset, the gOcad results based on available digital data recordsshowed that there was very sparse redox information for the Lake Frome region. Analogue (hardcopy) records, however, provided valuable additional information and were manually searchedand assigned redox values.The PIRSA drill hole dataset for the Lake Frome region, while not exhaustive, was extensive andrecorded the hole locations, elevations, depths and the report number in which the original drillhole information was recorded. Only some of the historical reports are available in digital form(Table 4.2, Fig. 4.2), from which pertinent data were extracted.As the drill log entries were not digital, redox values were derived by manually recording thedepth values, converting to metres where necessary, and assigning a value based on the list offilter words developed earlier for the Eromanga Basin (van der Wielen et al., 2009). Over 12,000new data points in 441 drill holes were recorded for the Lake Frome region. These values werethen entered into gOcad to create a three-dimensional map.Table 4.2: Reports used to map redox values in the Lake Frome region.Number Year Company # Drill holes # data pointsSML 102 1966 to 1967 Cominco Exploration Pty Ltd 22 342SML 147 1967 Cominco Exploration Pty Ltd 3 43SML 207 1968 to 1970 Australian Gold and Uranium Pty Ltd 27 177SML 243 1968 to 1970 Petromin NL 17 231SML 245 1968 to 1970 Petromin NL 40 478SML 461 1970 to 1971 Central Pacific Minerals NL 6 44SML 462 1970 to 1970 Petromin NL 4 83SML 544 1971 to 1973Pacminex Pty Ltd andEsso Australia Ltd49 825SML 579 1971 Petrocarb Exploration NL 2 23EL 5 1972 to 1973 Union Corp. (Australia) Pty Ltd 23 2209EL 6 1972 to 1973 Union Corp. (Australia) Pty Ltd 72 6631EL 41 1973 Nissho-Iwai Co. (Aust.) Pty Ltd 21 198EL 127 1974 to 1975 Tricentrol Australia Ltd 27 147EL 217 1975 to 1981EL 614 1975 to 1981Mines Administration Pty Ltd andTeton Exploration Drilling Company Pty LtdMines Administration Pty Ltd andTeton Exploration Drilling Company Pty Ltd20 21822 203EL 1977 1994 to 1996 North Mining Ltd 84 255* SML= Special Mining Lease; EL=Exploration LicencePage 45 of 151