Application of Satellite Remote Sensing for Estimation of Fault Distribution and Vegetation in the Dunhuang Area

摘要

This is a study to conserve the Dunhunag Mogao Grottoes in the arid region of China.The wall paintings in the caves are severely deteriorated by recrystallization of salt that is accumulated by the evaporation of moisture in the rock formation.Our aim is to understand the moisture movement from the Qilian Mountains to the Mogao Grottoes through the observation of the fault system and vegetations by satellite remote sensing.In this study,Landsat5-TM and Terra-Aster data are used for analyzing geological structures and vegetations in wide area.The NDVI map,which is analyzed by Quick Bird data,is useful to understand distributions of natural vegetation.In spite of low rainfall locally,significant natural vegetations grow up not only along the river but also on the sand dune and basement rock.We illustrate that some vegetations are distributed on the fault systems as straight lines in the Sanwei Mountains.These results indicate that moisture moves along the fault systems and the vegetations absorb it and grow on the faults.It is conceivable that moisture moves through the Mingsha Mountains,which have the same geological features as the Sanwei Mountains.And it indicates the possibility that moisture reach to the Mogao Grottoes from the southwest.