Patent ID: 8294466

Claim:
A hydrocarbon prospecting method for displaying electromagnetic field data from a controlled source electromagnetic survey of a subsurface region to enhance identification of resistive anomalies in the subsurface region, thereby locating resistive bodies causing the anomalies, comprising: (a) decomposing electromagnetic data from at least one survey receiver into frequency domain, and selecting amplitude data corresponding to at least two frequencies; (b) plotting the selected amplitude data with a scaled amplitude plotted on one axis vs. a scaled offset, where offset is source-receiver separation, on the other, with scale factors being chosen to substantially collapse data from the two or more frequencies to a single curve; and (c) identifying one or more resistive anomalies by comparing positive offset data to negative offset data; and (d) estimating location of a resistive body and potential hydrocarbon source that is causing an anomaly from location of the anomaly on the plot relative to location of the survey receivers.