Superparamagnetic effect over gold and nickel deposits

摘要

The results of investigations of the superparamagnetic (SPM) effect, which takes place with the transient electromagnetic method (TEM) process, are discussed. Depending on the objective of the investigations, the SPM-effect can be considered either as a disturbance or as a useful tool. In this paper we consider some ways of suppressing SPM noise when conventional TEM investigations are carried out, and the application of SPM for mineral deposits exploration. Such an application is based on specific properties of subsurface rocks and soil samples above gold and nickel deposits. It is shown, that anomalies with relaxation time constants of SPM-processes are spatially correlated with the ore deposits. The nature of the anomalies can be connected with the presence of a mixture of elements in ferromagnetic minerals producing an SPM-effect. It is proposed that these elements have been brought to the surface by upgoing gas flows from the deep-lying ore-containing bodies and are characteristic in tectonic fault zones. The spatial peculiarities and supposed mechanism of their formation give us a possibility to use them as a tool for exploration of certain types of mineral deposits, such as those of gold and nickel.