ABSTRACT
Magnetic susceptibility (MS) studies on soils over 19 oil and gas fields showed anomalously large amounts of diagenetic magnetic minerals in shallow-depth samples in about 89% of the cases tested.
Soil MS anomalies were compared with soil gas hydrocarbon (GHC) anomalies over 12 oil and gas fields (including several stratigraphic traps) and one gas storage reservoir. Samples were collected along the same profiles. Six examples are presented with detailed data listings.
Our goal is to test the utility of soil magnetic susceptibility and soil gas hydrocarbons as petroleum prospecting methods. We emphasize statistical evaluation of anomalies and their empirical correlation with producing areas and leads identified by other geochemical, geological, or geophysical data. For direct comparison of anomaly strengths, data are expressed statistically in terms of the appropriate background mean and standard deviation.
Soil MS and soil GHC data complement each other, providing better guidance to productive areas than either data set alone. When used in an integrated exploration program, their combined positive evidence of hydrocarbon presence under prospects could result in fewer dry holes than when drilling with structural information only.
