Abstract: A method and apparatus for real-time well-site interpretation of array resistivity log data. An inversion of data with different depths of investigation is carried out after data shoulder-bed correction. The formation model used by inversion is constructed with the layer boundaries obtained from an imaging tool or other log measurements.

Abstract: Different subsets of multiarray resistivity measurements are inverted using a corresponding resistivity model. The models are selected based at least in part on the resolution of the measurements. Results of the inversion are combined to give a single model consistent with the resolution and depth of penetration of each subset of the multiarray data.

Abstract: A method is disclosed for real-time (well-site) resistivity anisotropy determination using array lateral logs or any other unfocused, lateral-type measurements, and array induction logs or any other focused, induction-type measurements. Near-vertical wells with a deviation angle of less than 30 degrees are considered. Since with a lateral log, at each logging depth the injected current has both horizontal and vertical components, the data contains information related to both horizontal (Rh) and vertical (Rv) resistivities. With array induction tool, the induced current in near-vertical wells has only a horizontal component, and the induction data contain information related to Rh only. Having those two data sets acquired in the same well, it is possible to instantly estimate the formation resistivity anisotropy using square of a ratio between borehole and invasion corrected lateral and induction focused logs.

Abstract: A method for determining formation resistivity anisotropy in a wellbore environment. The method of the present invention effectively extends the dynamic range of the existing well logging service of the multi-component induction tool, allowing the use of this service in wells drilled with conductive WBM systems. A sequential inversion processing of galvanic array lateral log HDLL/MLL data or DLL/MLL and also multi-component induction log (3DEXSM) data is used. The formation resistivity structure of the near wellbore environment is determined using the galvanic measurements of the array lateral log tool.

Abstract: A method is disclosed for real-time (well-site) resistivity anisotropy determination using array lateral logs or any other unfocused, lateral-type measurements, and array induction logs or any other focused, induction-type measurements. Near-vertical wells with a deviation angle of less than 30 degrees are considered. Since with a lateral log, at each logging depth the injected current has both horizontal and vertical components, the data contains information related to both horizontal (Rh) and vertical (Rv) resistivities. With array induction tool, the induced current in near-vertical wells has only a horizontal component, and the induction data contain information related to Rh only. Having those two data sets acquired in the same well, it is possible to instantly estimate the formation resistivity anisotropy using square of a ratio between borehole and invasion corrected lateral and induction focused logs.

Abstract: A method for determining formation resistivity anisotropy in a wellbore environment. The method of the present invention effectively extends the dynamic range of the existing well logging service of the multi-component induction tool, allowing the use of this service in wells drilled with conductive WBM systems. A sequential inversion processing of galvanic array lateral log HDLL/MLL data or DLL/MLL and also multi-component induction log (3DEXSM) data is used. The formation resistivity structure of the near wellbore environment is determined using the galvanic measurements of the array lateral log tool.

Abstract: A system has been invented for producing a final earth model of part of an earth formation having N (one or more) layers, the method including, in one aspect, generating an initial earth model based on raw data produced by a wellbore logging tool at a location in a borehole through the earth, performing 2-D forward modeling on the initial earth model to produce an interim earth model that includes a set of synthetic tool responses data for the wellbore logging tool, comparing the synthetic tool response data to the raw data to determine whether there is misfit between them; if misfit between the synthetic tool response data and the raw data is acceptable, saving and storing the interim earth model as the final earth model; if misfit between the synthetic tool response data and the raw data is unacceptable, performing 1-D forward modeling N times on the interim earth model, producing a secondary earth model; performing 1-D inversion on the secondary earth model; and either saving the secondary earth model as t