The Induced Polarization (IP) method extends the resistivity method by making an additional measurement of the ability of the ground to store electrical charge. IP instruments measure both the conductive and capacitive properties of the subsurface using either time domain or frequency domain techniques. Spectral Induced Polarization (SIP) is generalization method of IP. Principle of SIP measurement is finding the sequence of time series is used to produce the resistivity spectrum. It can be used to measures the complex resistivity in dependence of frequency, remove EM coupling effects from IP data, and to identify the source of the IP response. Through these advantages, it is more reliable to detect hydrocarbon prospect. Since IP is sensitive to surface area with enhanced oxidation due to contaminant conversion, hydrocarbon prospect area indicates high resistivity very clearly.Data acquisition has improved using high-power transmitter, receiver with GPS-synchronization, CPU controls each auxiliary acquisition unit, and receives data via two-way wireless communication. Data processing approach to spectral parameters (phase-staggered fitting) that is designed for dipole-dipole SIP uses Cole-Cole and Brown Models. The combined model can be used to calculate electromagnetic spectral, resistivity and phase contrast, and then extract four spectral IP parameters by inverting and fitting the amplitude and phase spectra obtained by normalizing observed apparent resistivity.The SIP system provides more efficient field work, better signal-to-noise ratio, and increased exploration depth rather than the conventional method. However, equipment is heavy and field operations are relatively slow, particularly in complicated areas. Many tests and predictions have shown the usefulness of the method checkingknown traps for hydrocarbon, exploring for new hydrocarbon trap, and for optimizing drilling location.
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