[PPS08-12] Displacement-Length Ratios and Contractional Strains of Wrinkle Ridges in Thaumasia Minor and Solis Planum, Mars
キーワード：Displacement-length ratio, Contractional strain, Wrinkle ridge
Statistical analyses of the planetary tectonic structures such as faults, joints and dikes are established means to comprehend stress-strain conditions throughout the history of planetary bodies. The geometric properties of the tectonic structures have been used by earlier workers to infer the rudimentary mechanical controls that helped in their origin and evolution [1]. Studies confirm that within the fault on terrestrial and planetary surfaces the maximum displacement (Dmax) is proportional to its length (L). The Dmax-L ratios are therefore utilized to delineate an average long-term equilibrium stress field [2, 3]. Wrinkle ridges, formed above to blind thrust faults, are compressional structures found abundantly on Mars [4]. Wrinkle Ridges in Thaumasia Minor and Solis Planum were studied using MOLA/HRSC Blended DEMs. Topographic profiles, across trends, were extracted for each wrinkle ridge near their midpoints [cf. 2] to evaluate their height and maximum displacement (Dmax). Displacement and length values of the wrinkle ridges were plotted on a graph. The Dmax-L ratios (γ) for wrinkle ridges of both the regions are calculated by a linear fit method [cf. 2, 5]. The γ value of ridges in Thaumasia Minor was found to be (2 × 10−3) while that in Solis Planum is found to be (1.2 × 10−3). The contractional strains (ε) in Thaumasia Minor and Solis Planum are estimated to be ∼0.14% and ∼0.1% respectively (fault plane dip θ is assumed to be 25°). These estimated values indicate that the Thaumasia Minor is more affected by compressional tectonics than the adjacent Solis planum.
Acknowledgement: ISRO research grant is acknowledged.
Reference
1. Schultz, R.A., Klimczak, C., Fossen, H., Olson, J.E., Exner, U., Reeves, D.M. and Soliva, R., 2013. Statistical tests of scaling relationships for geologic structures. Journal of Structural Geology, 48, pp.85–94.
2. Li, B., Ling, Z., Zhang, J., Chen, J., Ni, Y. and Liu, C., 2018. Displacement-length ratios and contractional strains of lunar wrinkle ridges in Mare Serenitatis and Mare Tranquillitatis. Journal of Structural Geology, 109, pp.27-37.
3. Ruj, T., Komatsu, G., Pondrelli, M., Di Pietro, I. and Pozzobon, R., 2018. Morphometric analysis of a Hesperian aged Martian lobate scarp using high-resolution data. Journal of Structural Geology, 113, pp.1-9.
4. Watters, T.R., 1993.Compressional tectonism on Mars. Journal of Geophysical Research: Planets, 98(E9), pp.17049-17060.
5. Callihan, M.B. and Klimczak, C., 2019. Topographic expressions of lunar graben. Lithosphere, 11(2), pp.294-305.
Acknowledgement: ISRO research grant is acknowledged.
Reference
1. Schultz, R.A., Klimczak, C., Fossen, H., Olson, J.E., Exner, U., Reeves, D.M. and Soliva, R., 2013. Statistical tests of scaling relationships for geologic structures. Journal of Structural Geology, 48, pp.85–94.
2. Li, B., Ling, Z., Zhang, J., Chen, J., Ni, Y. and Liu, C., 2018. Displacement-length ratios and contractional strains of lunar wrinkle ridges in Mare Serenitatis and Mare Tranquillitatis. Journal of Structural Geology, 109, pp.27-37.
3. Ruj, T., Komatsu, G., Pondrelli, M., Di Pietro, I. and Pozzobon, R., 2018. Morphometric analysis of a Hesperian aged Martian lobate scarp using high-resolution data. Journal of Structural Geology, 113, pp.1-9.
4. Watters, T.R., 1993.Compressional tectonism on Mars. Journal of Geophysical Research: Planets, 98(E9), pp.17049-17060.
5. Callihan, M.B. and Klimczak, C., 2019. Topographic expressions of lunar graben. Lithosphere, 11(2), pp.294-305.