The C1 volcanic belt holding the largescale Axi gold deposit in the west Ti ansh an mountains is the northern part of the Yili rift. The main component of the volc anic belt consists of continental intermediateacid volcanic lava, volcanic clastic rocks an d quartzamphible andesitic porphyrite (subvolcanic rock), with sedimentary c onglomerates locally seen at the bottom of the volcanic belt. The volc anic activity of the belt is controlled by the nearlyEW trend (the firstgrad e s tructure) and the nearlyNS trend (the secondgrade structure) volcanic struct ures , and moreover the volcanic apparatus (the thirdgrade structure) locally remai ns. Th e volcanic belt was formed in an epicontinental extension circumstance during a short span from C11 to C21.