作　　者： ; ; ; ; ; ;

机构地区： 中国地震局地质研究所

出　　处： 《地震地质》 2012年第1期145-159,共15页

摘　　要： 科洛火山群的新生代火山共有23座,坐落于科洛河两岸,火山岩面积约为350km2,岩性主要为碱性玄武岩。由于地处NE向断陷盆地这一特殊的构造位置,科洛地区的火山活动及展布主要受到区域基底断裂的制约。火山喷发形式总体为中心式,属斯通博利式火山。火山活动可划分为上新世、更新世和全新世3期。上新世在断陷盆地边缘形成了一系列NE向线性展布的中心式溢出型火山,其中部分火山因风化剥蚀而失去了原有的火山地貌特征,仅保留盾形熔岩台地。早更新世火山活动相对平静。中-晚更新世火山活动仍受到NE向基底断裂的控制,但喷发中心、喷发方式及喷发强度均发生改变,火山由碱玄质火山渣锥和熔岩流组成。进入全新世以后南山喷发,其火山结构保存完好,裸露的熔岩台地保留了较好的微地貌特征。该期火山亦由碱玄质火山渣锥和熔岩流构成。在科洛火山群的火山活动过程中,其熔岩流覆盖了早期沉积地层,并对盆地中的河流进行了改造,最终导致该区断陷盆地初始地貌的改变。 Keluo volcanic cluster,which covers an area of ca.350km2,is located between the Greater Khingan Mountains and the Songnen Plain,Heilongjiang Province,and in the north of the famous Wudalianchi volcanic cluster.Twenty-three Cenozoic volcanoes that primarily consist of alkaline basalts are distributed along the Keluo River.The activities and distribution of this volcanic cluster are largely controlled by the regional basement faults,and consistent with the special tectonic setting of NE-trending fault basin.The Strombolian-type central eruption is the predominant eruptive type in this area.Volcanic activities in this area can be divided into three periods,namely,Pliocene period,Pleistocene period and Holocene period.During the Pliocene,a series of central-overflow-type volcanoes,which situated on the edge of the basin,were formed along the NE-trending faults.However,except for some shield lava platforms,most of the original volcanic geomorphic features have been destroyed by weathering.The volcanic activities of early Pleistocene were relatively quiet.But the eruption activities of the Mid-and Late-Pleistocene were also controlled by the NE-trending basement faults,and the eruptive center,type and intensity were all changed as well.These volcanoes are mainly composed of alkali-basaltic scoria cones and lavas.The Holocene volcanoes,as represented by Nanshan,have similar eruptive type and composition to the former ones,but their volcanic structures are well preserved.Some micro-morphological characteristics can be easily recognized at their outcrops.On the whole,the lava covered the former sedimentary strata and changed the river flows attributed to the volcanic activities of Keluo volcanic cluster,as a result,the original geomorphy in the basin was totally altered.

关 键 词： 黑龙江省 科洛火山群 火山地质 地质年代

领　　域： [天文地球] [天文地球]