燕山西部尚义盆地沉积岩区专题地质填图方法与成果

Methods and results of sedimentary geological mapping of special issues in the Shangyi Basin,western Yanshan Mountain

燕山运动是中国东部晚中生代重要的陆内造山运动,具有广泛而深远的地质影响。虽然前人对燕山运动的研究已近百年,积累了大量研究成果,然而目前对于燕山造山带的陆内造山过程仍存在很大争议。针对这一科学问题,选取燕山西部尚义盆地开展了1∶5万专题地质填图。在此基础上,通过盆地充填序列、岩相、沉积环境、物源的综合分析,恢复了盆地岩相古地理,建立了盆地演化模型,并探讨了燕山造山带陆内造山过程的沉积响应。根据沉积岩区岩相组合填图方法,绘制了1∶5万组-相级岩相分布图。燕山西部尚义盆地侏罗纪—早白垩世早期沉积演化记录了燕山造山带造山前伸展、同造山挤压和造山后伸展的全过程。

The Yanshan movement was an important intra-continental orogenic movement in East China during the Late Mesozoic,causing extensive and significant influence. Although researchers have studied the Yanshan movement for nearly one hundred years and achieved lots of results,the intra-continental orogeny of the Yanshan orogenic belt remains a problem of much controversy. To tackle this problem,the authors chose the Shangyi Basin in western Yanshan Mountain to carry out 1∶50000 special geological map-ping. On the basis of the geological mapping,an integrated analysis of basin filling sequences,lithofacies,sedimentary environment and provenance was conducted to reconstruct lithofacies paleogeography,construct basin evolutionary model and discuss sedimentary response to the intra-continental orogeny of the Yanshan orogenic belt. A 1∶50000 formation-facies lithofacies geological map was completed by the method of sedimentary lithofacies association mapping. The sedimentary evolution of the Shangyi Basin in the western Yanshan Mountain recorded the whole process of pre-orogenic extension,syn-orogenic compression and post-orogenic extension of the Yanshan orogenic belt.