���ĴӶ�����ϡ���ɽ�������ҽ�ͨ���ȷ��������������Χ�Ӷ��ݻ��׶��Ѽ���֮ƥ��Ĵμ����ѿ��ư��Ѽͻ�ɽ����γ��ܻ��׶��ѿ��Ƶ����� NNW ��չ���Ļ�ɽ�ҷ����������ڻ��׶���������ͬ������ɽ�Ҵ��ֱ��������ʽ����϶ʽ�͸���ʽ���ֲ�ͬ���緢���������Χ�Ӷ��ݰ��������ϸ���ʱ���������׶����ϲ����� NWW ������ʽ���ѣ����¹�ͨ���׶��ѣ�Ϊ������ɽ�ҽ�����ͨ������ӳ����ʷʱ���ڻ�ɽ���ǿ������������������ɽ��ģ���Ա�����Ϊ��������Ϊ����������ࡣ��ɽ�ҵķֲ��ܻ��׶��Ѽ���ͨ��Ĵμ����ѿ��ƣ�ͬʱ�Զ��Ѻۼ���һ���ĸ������á�

The authors pointed out that Cretaceous volcanic activities were controlled by the basement faults and secondary faults in Xujiaweizi��and formed three NNW �� trend volcanic rock belts controlled by basement faults��through the study on the relationship among fracture combination��volcanic mechanism and karst channels�� Due to the different characteristics of the basement faults��the volcanic rock belts had three eruption characteristics: center��fracture��and compound in type�� The careful dissection of Xujiaweizi fault depression in Anda area showed that: the NWW �� trend echelon fractures developed in upper basement fractures and communicated the basement faults downward��which were the volcanic magma invasion routes in western area�� These phenomenon reflected the volcanic activity stronger in the west than in the east in the history period��i. e�� the volcanic scale was larger in the west��charactered by burst facies��while showed effusive facies in the east�� The distribution of volcanic rocks were controlled by basement faults and secondary faults��which also played a remolding part to fracture trace��