Construction of the Trans-Alaska Pipeline System with the Denali Fault, a major cause of earthquakes, and with large amounts of permafrost. In 1969, the unincorporated Trans-Alaska Pipeline System group drilled a series of core samples north of the Brooks Range that demonstrated how ubiquitous the permafrost was along the route. This forced the design of an elevated pipeline, which was tested in a loop built near Barrow. This elevation required the pipeline to be insulated, since extreme cold temperatures caused the metal to become brittle, even when hot oil was being pumped through the pipeline. After ecological objections forced subterranean pipeline crossings (in order to allow
Central Asia–China gas pipeline from the Karachaganak, Tengiz and Kashagan gas fields. The branch line will have a capacity of 15 billion cubic meters of natural gas per year. It will be commissioned in 2014. Central Asia–China gas pipeline The Central Asia–China gas pipeline (known also as Turkmenistan–China gas pipeline) is a natural gas pipeline system from Central Asia to Xinjiang in the People's Republic of China. By connecting Turkmenistan to China’s domestic grid, this pipeline makes it possible to transport gas some 7000 km from Turkmenistan to Shanghai The initial proposal for Central Asia–China gas pipeline was presented as the Kazakhstan–China gas pipeline,