Geological characteristics of paleovolcanic edifices in the Xiong'er Group, Ruyang County, Henan, and their significance

Abstract：Volcanic rocks are widespread in the Mesoproterozoic Xiong'er Group in western Henan and have undergone repeated structural activities, magmatic intrusion and erosion. On the basis of the remaining primary structures of rocks, paleo-faults and petrological and petrographic indicators, attitude of strata and geomorphologic features, a series of paleovolcanic craters, such as the Gaoshuiquan, Guanjia, Caoliba, Shibapan and Shuangyuangou paleovolcanic craters, have been identified in the Ruyang area. The early-stage paleovolcanism was marked by NEE-trending fissure-type outpouring, the middle-stage paleovolcanism evolved into central eruption, accompanied by fissure eruption, and the late-stage paleovolcanism was manifested by central eruption. Regional volcanism occurred throughout the Xiong'er period and from NE to SW with time. The paleovolcanic craters and the subvolcanic rocks controlled by the paleovolcanic edifices provide regional ore search information.