Consideration of organic matter content in source rocks plays an important role in the assessment of the petroleum potential of sedimentary basins. CARBOLOG @ is a new method developed at the Institute Franpis du P& trole (IFP) for estimating the organic content of potential source rocks. This method exploits the physical properties of the organic matter, which are characterized by high sonic transit time and by high resistivity. These physical properties can be combined to derive an in situ estimation of the organic matter content of the sediment from wireline logging information. In a given well, the distribution of organic carbon is evaluated by a procedure that combines the measurements of two types of wireline logs routinely available in petroleum boreholes, the sonic log and the resistivity log. To apply the method on the scale of a sedimentary basin, it is necessary to make a calibration based on wells for which the analytical data on organic carbon content are available. Our method has been tested on immature or slightly mature marine source rocks belonging to different basins and exhibiting various lithofacies. The results obtained clearly demonstrate the ability of the method to estimate the organic carbon contents and to continuously indicate their vertical variations. Other tests are currently under way on different depositional environments and more mature formations to identify the possibilities and limits of the method in the overall geological settings generally encountered.

This content is only available via PDF.
You do not currently have access to this content.