Schlumberger Technology Corporation

Cheng Bing Liu

Qiming Li

Jacques R Tabanou

Peter T Wu

Jan Smits

Frank Shray

Techniques for determining a formation property by simplifying various two-geological-layer or multi-geological-layer models into a multi-electrical-layer model. A volume fraction of a layer in a multi-electrical-layer model is determined for an anisotropic region (sliding window) of the formation. The multi-electrical-layer electrical model includes a relative-lower-resistivity layer and a relative-higher-resistivity layer. A high-resolution resistivity measurement is used in the determination and resistivities for the relative-lower-resistivity layer and for the relative-higher-resistivity layer based on the volume fraction and bulk resistivity measure ments of the anisotropic region are determined. The formation property is based on the volume fraction, the resistivity of the relative-lower-resistivity layer, the resistivity of the relative-higher-resistivity layer, a total porosity of the anisotropic region, and bulk resistivity measurements of the region.

Methods and systems for resistivity anisotropy formation analysis

A method for identifying environmental effects in well log data includes selecting a plurality of models, each of the plurality of models including at least one parameter to be optimized; fitting the models to the well log data by optimizing the at least one parameter, the fitting producing a plurality of optimized models; determining an indicator of goodness of fit for each of the plurality of optimized models; and selecting a model representing a best fit of the well log data based on the indicator.

Intelligent diagnosis of environmental influence on well logs with model-based inversion

A method of identifying the fluid type of subterranean formations according to the correlation between the variation trend of electrical resistivity with depth downhole in a borehole and the variation trend of porosity with depth downhole in the same borehole. The method includes the steps of: a) determining the rate of change with depth of a resistivity parameter (such as deep resistivity) of the formation surrounding the borehole; b) determining the rate of change with depth of a porosity parameter (such as total porosity and/or free fluid porosity measured by a nuclear magnetic resonance technique) of the formation surrounding the borehole; c) determining a comparison of the rate of change with depth of such resistivity parameter and the rate of change with depth of such porosity parameter for a given depth in the borehole; and d) using the comparison to determine the nature of the fluid in the formation surrounding the borehole at that depth downhole or in a given depth window downhole.

Growing community of inventors

Houston, TX, United States of America

Cheng Bing Liu