Magnetic susceptibility is associated with oil-bearing intervals in an oil field, north central Kansas

摘要

Magnetic susceptibility is a relatively unexploited tool in petrophysical core and well cutting analysis. In this study, we investigated the variability in magnetic susceptibility in well cuttings from an oil-bearing interval located between 3000 feet and 3900 feet below the surface. The goal was to investigate possible causal relationships between the magnetic anomalies and the hydrocarbon accumulations. The cuttings were sampled every 10 feet. The magnetic susceptibility data was correlated with geophysical logs to identify variations of magnetic susceptibility values in the oil-producing unit. Results show that high magnetic susceptibility values correlated with intervals that produced "dead" oil, gamma ray and acoustic transit time. We suggest from our results that magnetic susceptibility can be used as an additional tool for petrophysical analysis of cuttings and as an indication for the presence of hydrocarbons and potentially to assess the quality of the oil in the oil-bearing intervals prior to production.