Supplementary material for

Transient deformation during the Milashan Tunnel construction in northern Sangri-Cuona Rift, southern Tibet, China observed by Sentinel-1 satellites

Yunfeng Tiana, Jing Liu-Zengb, Yi Luoa, Yongsheng Lia, Yingshun Huc, Bin Gongd, Lizheng Liue, Ping Guoe, Jingfa Zhanga

aKey Laboratory of Crustal Dynamics, Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085, China.

bState Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China.

cNaqu Digital Seismic Station, Xizang Earthquake Administration, Naqu 852000, China.dChina Railway Erju 5th Engineering Co., Ltd., Chengdu 610091, ChinaeChina Railway Erju Group Co., Ltd., Chengdu 610000, China

This supporting information provides the supplementary figures for the main text. Fig. S1 shows the interferograms used in the SBAS analysis. Fig. S2 displays the InSAR LOS mean deformation rate maps. Fig. S3 shows the topography and construction progress log of the Milashan Tunnel. Fig. S4 presents the relationship between water discharge and surface deformation.

Fig. S1. The interferograms used in the SBAS analysis. (a) The ascending track. (b) The descending track. The circles represent the Sentinal-1 acquisitions. The dashed lines link the two scenes used to form the interferograms that serve as the input for the SBAS analysis.

Fig. S2. InSAR LOS mean deformation rate map. (a) The ascending track. (b) The descending track. Negative values (red) represent subsidence (moving away from the satellite along the LOS direction). The solid lines indicate the locations of the main and side tunnels of the Milashan Tunnel project. The dashed lines are the locations of the LOS velocity rate profiles in Fig. 2.

Fig. S3. The topography (a) and construction progress log (b) of the Milashan Tunnel. In (a), the long and short lines represent the main tunnel (AB) and the side tunnel (CD), respectively and squares indicate the locations of the time series shown in Fig. 3. The filled regions in (b) indicate the finished parts of the tunnel as of October 2017.

Fig. S4. Water discharge and surface deformation near the entrance of the side tunnel (#25 in Fig. 3). The squares are LOS displacements and the dashed line is the modeled curve. The solid curve indicates accumulative water discharge volumes.