CREC4 technicians show surveying tools used in building the Xining-Chengdu railway to a young Tibetan woman in Gansu province. The technicians from CREC4 Seventh Engineering were surveying the terrain in Luchu county under Gannan Tibetan autonomous prefecture, preparing to help build the Xining-Chengdu railway, which links Northwest China's Qinghai and Gansu provinces with Sichuan province in Southwest China. The CREC4 …