Abstract: A method includes receiving information that includes elastic property information and that includes sonic data acquired via a tool disposed at a plurality of depths in a bore in a subterranean environment that includes at least one anisotropic formation; processing the information to generate processed information where the processed information includes variance information associated with the elastic property information and where the processed information includes velocity information and orientation information associated with the sonic data; performing an inversion based at least in part on the processed information; and outputting values for elastic parameters based at least in part on the inversion.

Abstract: A computer-implemented method for determining elastic properties for a heterogeneous anisotropic geological formation is described herein. The method includes grouping sonic velocity data from a borehole section (or borehole sections) into a number of clusters (e.g., one or more clusters). The sonic velocity data is grouped into clusters using petrophysical log data from the borehole section. The method also includes inverting the sonic velocity data for the clusters to determine elastic properties for each cluster. In some cases, the elastic properties for the clusters are combined to determine a relationship between the elastic properties and formation heterogeneity.

Abstract: A computer-implemented method for determining elastic properties for a heterogeneous anisotropic geological formation is described herein. The method includes grouping sonic velocity data from a borehole section (or borehole sections) into a number of clusters (e.g., one or more clusters). The sonic velocity data is grouped into clusters using petrophysical log data from the borehole section. The method also includes inverting the sonic velocity data for the clusters to determine elastic properties for each cluster. In some cases, the elastic properties for the clusters are combined to determine a relationship between the elastic properties and formation heterogeneity.

Abstract: Methods and apparatus for estimating stress characteristics of formations. The method comprises: (a) acquiring sonic anisotropy data, image data or both associated with at least one borehole (b) employing sonic anisotropy data to estimate fast shear direction (FSA) to extract FSA observed data; (c) computing FSA from forward modeling, forward modeling utilizes a first deviatoric stress tensor to extract FSA predicted data; (d) computing FSA misfit from difference between FSA observed data and FSA predicted data to obtain computed FSA misfit relating to first deviatoric stress tensor; (e) if computed FSA misfit is equal to or less than a defined value, then store computed FSA misfit, otherwise repeat steps (d)-(h) using another deviatoric stress tensor so a different deviatoric stress tensor is used for each repeat; (f) selecting smallest stored computed misfit from group consisting of stored computed FSA misfit, at least one other stored computed misfit or combination thereof.

Abstract: Methods and apparatus for estimating stress characteristics of formations. The method comprises: (a) acquiring sonic anisotropy data, image data or both associated with at least one borehole (b) employing sonic anisotropy data to estimate fast shear direction (FSA) to extract FSA observed data; (c) computing FSA from forward modeling, forward modeling utilizes a first deviatoric stress tensor to extract FSA predicted data; (d) computing FSA misfit from difference between FSA observed data and FSA predicted data to obtain computed FSA misfit relating to first deviatoric stress tensor; (e) if computed FSA misfit is equal to or less than a defined value, then store computed FSA misfit, otherwise repeat steps (d)-(h) using another deviatoric stress tensor so a different deviatoric stress tensor is used for each repeat; (f) selecting smallest stored computed misfit from group consisting of stored computed FSA misfit, at least one other stored computed misfit or combination thereof.