Controlled source electromagnetic deep sounding: Theory, results and correlation with natural source results

摘要: Controlled source electromagnetic (EM) methods represent a unique set of geophysical experiments which can be used to determine the properties and state deep continental crust. Unlike natural EM methods, an artificial technique designed optimize resolution minimize interactions with local structure. The major drawbacks include restricted depth penetration, insufficient data sets limited number modelling algorithms. Information about electrical conductivity at lower crustal depths obtained but expense requiring large moment sources, sophisticated processing techniques redundancy. Moreover, are sufficiently complicated that numerical is often necessary for quantitative interpretation. It therefore essential record enough information justify choice interpretation algorithms, particularly since controlled forward routines generally very restrictive not widely available. As most interpretations based on layered earth models, observations all field components useful testing “dimensionality” justifying interpretations.