An overview of wellbore methods of investigating stress state of the upper layers of the earth’s crust

Abstract

The wellbore methods for studying the stress-strain state of the upper layers of the Earth’s crust are overviewed. Some main methods for stress estimating from wellbore data are presented alongside with the analysis of their applicability and uncertainty appearing after their application. The reconstruction of stress profiles along the well trajectory based on the data on wellbore breakouts, drilling-induced tensile fractures, elastic wave propagation in the well surrounding the rock masses, and regularities in the spatial orientation and distribution of natural fractures is discussed. The estimation of stress state parameters based on minifracs and leakoff tests as well as on strain recovery techniques from the oriented core samples from wells is described.