Quantitative Zoning Assessment of Crustal Stability Along the Yunnan–Tibet Railway Line, Western China

The planned Yunnan-Tibet railway goes through the northwest of Yunnan Province and the southeast of the Tibet Autonomous Region.Because of its location near the collision belt of the Eurasian and Indian plates,complex engineering geological conditions and difficult engineering geological problems are encountered.The study is aimed at making the zoning assessment of crustal stability along the railway line so as to provide a better base for its construction,especially its line selection.For this purpose,the following seven influencing factors of crustal stability were selected and quantified by grading and scoring:active fault,seismic activity,geo-stress field,geo-strain field, geothermal field,geo-hazard,and lithologic character.Of these factors,the active fault,seismic activity and geo-hazard are the three most prominent factors influencing the railway construction.Along the railway line there are 1731703 calculation units to be divided.The zoning assessment calculation was completed by ArcGIS-based information fusion method.The assessment results aid railway line selection and show that there are 10 stable sectors,28 relatively stable sectors,23 relatively unstable sectors,and 20 unstable sectors along the Yunnan-Tibet railway line.