Geophysical Prospecting Method for Boulder

Boulders on tunnel alignment is adverse for shield tunneling and geophysical prospecting is commonly used in boulders detecting along shield tunneling alignment.In this paper,the geophysical characteristics of boulder area are introduced and the geophysical prospecting methods for boulder are classified and presented,including gravity prospecting,electrical prospecting,seismic prospecting,well logging and compositive geophysical prospecting.In addition,the comparison of two prospecting methods or several prospecting methods by compositive geophysical prospecting can improve the precision of geophysical prospecting.Thus this paper can provide references for boulder detecting in various conditions by geophysical prospecting.