Airborne magnetic surveying for petroleum exploration continues to routinely and indisputably reveal interesting and measurable magnetic anomalies (as small as 0.1 nT under the best survey conditions) which arise from geological variations within the sedimentary section. These so-called intra-sedimentary magnetic anomalies are detectable from aeromagnetic data acquired with stringent aeromagnetic survey design and acquisition specifications/techniques. Thus, often only new or recent vintage data (typically less than fifteen or so years old) is suitable for reliably mapping sedimentary magnetic effects.
While there is no doubt as to the existence of sedimentary magnetic anomalies, there is considerable lack of knowledge and experience as to the correct interpretation of such anomalies. The lack of interpretational expertise is apparently directly related to both the lack of sufficient “ground truthing” of the observed anomalies, and the lack of shared knowledge and “best practices” among magnetic interpreters regarding these anomalies. Thus most interpretation has tended to be fairly empirical, consisting in most instances of postulated correlations between mapped magnetic anomalies and suspected geologic features.
- To demonstrate, through modeling, diapiric and detached salt features which can be
expected to generate sedimentary magnetic anomalies.