摘要
针对徐家围子断陷安达地区营城组火山岩具有多期喷发、火山岩机构类型多样、叠置分布和岩性复杂的特点,对火山岩喷发期次及火山岩形成演化特征进行研究,找出火山岩的演化规律。其主要表现为:沙河子组沉积末期,本区处于断-拗转换期,盆地内部处于欠补偿特征;营城组一期火山喷发时,主要受西部的活动基底断裂及次级断裂的控制;营城组二期火山喷发时,火山作用由安达西部向东部扩展;营城组三期火山喷发时,深部岩浆活动由强转弱,本区的基底断裂活动减弱,构造活动也向坳陷期形成环境过渡。
According to the characteristics of volcanic multiphase eruption,various types of mechanism,superimposed distribution and complicated lithology in Yingcheng Formation of Anda area in Xujiaweizi fault depression,the authors have studied the volcanic evolutionary rule through research on volcanic eruption stages and volcanic formation-evolutionary characteristics.The main performance was that this area was in fault-sag transition stage in the end of Shahezi Formation,and basin internal was characteristic in the under-compensation.When volcanic eruption at the first phase of Yingcheng Formation,it was mainly controlled by the activities of the west base fault and secondary fracture.When volcanic eruption at the second phase of Yingcheng Formation,volcanism extended from west to east in Anda area.When volcanic eruption at the third phase of Yingcheng Formation,deep magmatic activities were from strong to the weak,and the activities of the base fault were weakened,and tectonic activities were transferred to formation environment of depression period.
出处
《世界地质》
CAS
CSCD
2014年第2期247-254,共8页
World Geology
基金
国家重点基础研究"973"项目(2009CB219308)
关键词
安达地区
营城组
火山岩
喷发期次
演化规律
Anda area
Yingcheng Formation
volcanic rock
eruption stages
evolutionary rule
