Schlumberger

Isotope Logging

Overview Library

Continuous ╬┤13C-CH4 measurements in real time

Isotope logging provides a completely new dataset, helping the geochemical characterization of hydrocarbons in the formation in real time and on a continuous basis.

Geological and geochemical insights

  • Isotope logging is a tool for the identification of reservoir connectivity and compartmentalization. It also provides the means for evaluating the sealing characteristics of cap rocks and faults.
  • δ13C-CH4 data provides information about encountered hydrocarbons, their origins, characteristics, and behavior in the subsurface. Because δ13C-CH4 ratios are related to hydrocarbon generation, they provide information about the hydrocarbon source rock including its kerogen type and thermal maturity. This information can be used for correlating hydrocarbons with their source. The genetic information obtained from δ13C-CH4 ratios might provide information about a possible pay zone.
  • In conjunction with the quantitative composition derived from the FLAIR service, isotope logging provides additional information about the similarity or dissimilarity of hydrocarbons encountered in the subsurface, useful for the optimization of downhole sampling.
  • In-reservoir processes—including biodegradation and water washing—alter the isotopic composition of methane. Isotope logging can be used to identify the presence of such processes, and possibly their type and magnitude.

Greater depth resolution with less risk

Continuous, quality-controlled measurement of δ13C-CH4 provides dramatically improved depth resolution and the identification of small-scale features that would otherwise be missed. There is the possibility of obtaining data in places where gas sampling is difficult or impossible. In addition, uncertainties and risks associated with collection, shipment, and analysis of samples are reduced or eliminated.

Integrated interpretation

The integration of δ13C-CH4 ratios, available in real time, with data from other sources allows an immediate, more accurate interpretation of the geological and geochemical system, helping to optimize key decisions affecting the development of the reservoir.

Request More Information