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Summary PEMEX has acquired more than 9500 km 2 of wide-azimuth 3D controlled-source electromagnetic (CSEM) data as part of its deep water exploration program since 2010. The acquisition campaign is carried out systematically on a portfolio level and is designed to provide resistivity imaging on both prospect and regional scale. We present four examples of integrated interpretation with 3D seismic, demonstrating the information that can be extracted from the 3D CSEM data and applications of this information. The first example focuses on prospect maturation, where a resistivity anomaly is used as a direct hydrocarbon indicator (DHI). We discuss how evaluation of anomaly characteristics, such as correlation to seismic attributes, and field size estimation based on the area and strength of the anomaly can influence a prospect’s probability of economic success. In the second example, we study potential drilling hazards and show how CSEM can help to identify gas hydrate variability in terms of thickness and concentration over a bottom simulating reflector (BSR). The third example relates to petroleum system analysis where CSEM inversion results are used to study the composition of diapirs, i.e. salt versus shale, and identify fluid migration pathways resulting from faulting. The last example describes regional mapping of resistivity, which may indicate variations in lithology, identify potential shallow hazards and even generate new leads. The cases we present exemplify the value of using CSEM systematically in a large frontier exploration program. |
