Abstract: The authors have taken the boneshaped boudins of two different stages into account. With the assumption that thickness of joints of the ‘bone’ is approximately the same as the original thickness of the layers of the boudins,the original length of the boudins has been reconstructed with the equalarea method to measure their finite strain. Meanwhile, this equalarea method is demonstrated by physical modeling, showing that the errors are 3.23%, 2.84%, 3.94% and 6.82%, respectively. This new strain gauge is successfully applied in the finite strain determination of rocks embedded boneshaped boudins and developed in Tieshan, Hubei, indicating the extension finite strain of the layers ranges from 33.80% to 48.22%. This result is relatively consistent to the other method applied in the measurement of the boudins’ finite strain. Furthermore, the authors have also successfully segregated the finite strain in two structural deformation periods.

Key words: boneshape boudins, strain determination, equalarea method, Tieshan, Hubei