【作者】 Pospelov I.I； 边千韬；

【Author】 Pospelov I.I~a.,Bian Qiantao~b a.Geological Institute,Russian Academy of Sciences,Moscow 109017,Russia b.Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China

【机构】 俄罗斯科学院地质研究所； 中国科学院地质与地球物理研究所；

【摘要】 早石炭世裂谷作用在亚洲地质构造演化过程中起了重要作用。早石炭世裂谷作用有两个演化系列:（1）从大陆裂谷向大陆边缘沉积盆地演化,如杜内期形成的维尔赫扬斯基大陆边缘沉积盆地;（2）从大陆裂谷向海洋演化,如古特提斯。裂谷的形成演化过程可分前裂谷、裂谷和后裂谷3个阶段。维尔赫扬斯基裂谷的前裂谷阶段（D₂—C₁）表现为这部分西伯利亚板块的隆起和法门阶遭受强烈剥蚀。在古特提斯（北帕米尔、昆仑山、秦岭）前裂谷阶段表现为线型基地隆起和法门阶遭受剥蚀。裂谷阶段始于隆起轴部崩塌,接着出现沉积和火山作用。裂谷建造底部为淤积物、洪积物,向上出现大量火山岩和火山碎屑岩,它们常与碳酸盐—碎屑岩混合,常见滑塌堆积。火山岩的特征是高Ti（TiO₂=3.8～5%）、高FeO*、高P₂O₅、高碱、低Mg。火山岩中占优势（50%以上）的是高硅流纹岩（SiO₂平均为78.80%）,其次是玄武岩类,安山英安岩极少。裂谷建造中玄武岩的年龄可以推断裂谷开始形成的时代。沿古特提斯缝合带,北帕米尔保存有相当多的裂谷建造。最近我们在东昆仑南部发现的高Ti（TiO₂达5%）斜长岩可能是此裂谷产物。东昆仑以南在早石炭世已步入裂谷后阶段—古特提斯洋阶段。更多还原

【Abstract】 The Early Carboniferous rifting had important effect on tectonic evolution of Asia. There are two evolutionary system of rifting:（1） from a continental rift to an epicontinantal sedimentary basin（e.g.Verheyangsiji epicontinantal sedimentary basin formed in Tournaisian）,（2） from a continental rift to an ocean（e.g.Palaeotethys）.The evolutionary process of the rifting was roughly subdivided into 3 stages:prerifing,rifting and opirifting.The part of the Siberian plate upheaved and the Famennian was denuded strongly in the Verheyangsiji area in prerifting stage （D2-C1）.The basement upheaved linearly and the Famennian was denuded in north Pamirs,Kunlun Mts.and Qinling Mts.in prerifting stage.The rifting stage commenced with dilapidation of upheaval axis,then sedimentation and volcanism took place.The lowest part of a rifting formation consists of alluvium and diluvium.Upward,a great lot of volcanic rocks,volcaniclastic rocks,carbonate-clastic rocks,and mixed rocks of them,as well as olistostrome present in rifting formations.The volcanic rocks are characterized by high TiO₂ contents（TiO₂=3.8～5%）,and high FeO^*,P₂O₅ and Na₂O+K₂O contents,low MgO contents.Rhyolite with high SiO₂ content（average SiO₂=78.80%） is dominant （more then 50%）,basalt is secondary,and Andesite-dacite is thimbleful in the volcanic rocks.The formation age of the rift can be deduced by the age of the basalt.The rifting formation presents in the north Pamirs along the Palaeotethyan suture zone.A plagioclase rock pluton with high TiO₂ content found in the south part of the East Kunlun Mts.may be resulted from the rifting.Opirifting stage,Palaeotethyan stage,had come in Early Carboniferous to the south of the East Kunlun Mts.更多还原