The stress measurements in sandstone of Youngs Modulus= 16 GPa and Poison's Ratio= 0.25 indicate stress as shown below:

Dip Bearing

01 = 19.4 MPa 20 210 02 = 16.1 MPa 30 1110 03 = 5.4 MPa 87 273

What would the maximum principal stress be (in MPa) if the stress field was measured in an adjacent siltstone of Young's Modulus = 10.3 GPa and Poison's Ratio = 0.25 ? The stress normalizing calculations are given below: ONL=(EN/E.) X (OML - O.V/(1- v)} + 0, v/(1- v) Where:

ONL = Normalised Lateral stress EN/EM = Ratio of Normalised and Measured Young's Modulae OML = Measured Lateral stress Oy = Measured Vertical stress = Poison's Ratio