GEOLOGICAL HAZARDS IN THE AREA FOR THE CONSTRUCTION OF PIPELINES IN THE PROJECT OF DIVERSION OF NATURAL GAS FROM THE WESTERN TO THE EASTERN REGION

The physical geographical and geological environmental conditions in the area for the construction of pipelines in the project of diversion of natural gas from the western to the eastern region are complex and variable.The geological hazards in the area show the regional distribution pattern.With the Mu Us desert and the eastern foothills of the Taihang Mountains as the boundaries, the whole area may be divided into the west section, central section and east section.In the west section, the main hazards are eolian erosion and sand-burying, corrosion by saline soils and expansion of salt, as well as mud flows and flood erosion.Landslides, collapses, mudflows, caving-in in mined-up areas and water creep and collapsing of loess when wetted are the main hazards in the central section.In the east section, the hazards are mainly ground subsidence, ground cracks and expansion and shrinkage of expanded soils.The central section is the most dangerous part of the pipeline project area where there are the most types of geological hazards and the most serious hazards;so the monitoring and early-warning system should be set up in this section.