【摘要】 辽河盆地是中、新生代发育起来的裂谷盆地,东部凹陷是辽河盆地新生代火山活动最为频繁的地区,发育大量火山岩。通过对东部凹陷测得的28个火山岩样品K-Ar年龄数据,结合区域火山岩石学、地球化学研究结果,对比前人曾发表的K-Ar年龄数据,将本区新生代火山活动分为房身泡、沙三、沙一和东营4个时期,始于65Ma,并在42~38Ma和32~25Ma经历2个活动高峰期。这为渤海湾盆地新生代构造演化乃至中国东部新生代裂谷活动研究,增加了同位素年代学方面的有力证据。更多还原

【Abstract】 Liaohe basin is a Cenozoic rift valley with numerous volcanic activities developed in East Depression. Based on the large amount of K-Ar geochronology, petrology and geochemistry data, the Cenozoic volcanic activities in this depression are divided into 4 periods, which are Fangshenpao, Shasan, Shayi and Dongying periods. The Shasan and Dongying periods are two summits of volcanic activities, with accurate isotopic age of 43～38?Ma and 32～25?Ma respectively. This paper provides an accurate isotopic chronology constraints for the study of Cenozoic tectonic evolution of Bohai basin and Eastern China.更多还原