【作者】 王旖旎； 张梅生； 李晓波； 杨明； 张栋；

【Author】 WANG Yi-ni,ZHANG Mei-sheng,LI Xiao-bo,YANG Ming,ZHANG Dong (College of Earth Sciences,Jilin University,Changchun 130061,China)

【机构】 吉林大学地球科学学院；

【摘要】 辽宁兴城茶棚庵、月亮山、夹山地区中元古界大红峪组底部发现一套海啸岩(Tsunamite)。海啸沉积物不整合于太古宙绥中花岗岩、团山子组之上,大红峪组正常背景沉积之下,厚约10m。以撕裂的碎屑、较差的分选性、沉积物粒度向上变细、成分复杂为特征,其物源主要来自下伏地层的碎裂或崩塌,准原地或异地沉积而成。结合中元古代岩相古地理特征分析认为,海啸事件很可能与团山子期末到大红峪期初的兴城运动有关,海啸沉积经历了产生、传波、洪泛、沉积和回流等阶段。大红峪组海啸沉积物的发现为兴城运动的研究提供了新的素材和方向,也有助于讨论华北板块、燕山裂陷槽以及Columbia超大陆在特定时期的演化历史。更多还原

【Abstract】 Tsunamites from the bottom of the Mesoproterozoic Dahongyu Formation are newly discovered in three sections(Chapen’an,Yueliangshan,Jiashan),in Xingcheng area,Liaoning Province.The 10 m thick tsunami deposits overlay unconformably on the Archean Suizhong Granite,the Mesoproterozoic Changzhougou Formation and the Tuanshanzi Formation.They are covered by normal background depositions of the Dahongyu Formation.Tsunami deposits are characterized by rip-up clasts,less well sorted grain,fining-upward sequences,complicated components.The major sources were produced by the collapse and avulsion of underlying strata,and their parautochthonous and allochthonous depositions formed tsunamites.According to characteristics of Mesoproterozoic lithofacies and paleogeography,the tsunami is most probably related to the Xingcheng Movement in the transition time of the Tuanshanzi Stage-the Dahongyu Stage.Tsunami deposits went through several stages of generation,propagation,inundation, deposition and backwash.Above discoveries provide new materials and orientations for the study of the Xingcheng Movement,and help to understand the evolution of the North China Plate,the Yanshan Aulacogen and the Columbia Supercontinent at a certain period.更多还原