Mineral Exploration Using Subtle or Negative Geochemical Anomalies

Abstract

Mineral resources prediction and assessment is one of the most important tasks in geosciences. Geochemical anomalies, as direct indicators of the presence of mineralization, have played a significant role in the search of mineral deposits in the past several decades. In the near future, it may be possible to recognize subtle geochemical anomalies through the use of processing of geochemical exploration data using advanced approaches such as the spectrum-area multifractal model. In addition, negative geochemical anomalies can be used to locate mineralization. However, compared to positive geochemical anomalies, there has been limited research on negative geochemical anomalies in geochemical prospecting. In this study, two case studies are presented to demonstrate the identification of subtle geochemical anomalies and the significance of negative geochemical anomalies. Meanwhile, the opportunities and challenges in evaluating subtle geochemical anomalies associated with mineralization, and benefits of mapping of negative anomalies are discussed.

Keywords

geochemical prospecting / subtle geochemical anomalies / negative geochemical anomalies / spectrum-area multifractal model / GIS

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