CAJ | 학술논문

华北地区寒武系中发育有大量的风暴沉积，对于此类沉积物的成因前人意见趋于统一，但对其沉积环境的认识仍存在较多争议。在野外细致观察、实测的基础上，结合室内沉积学描述和分析，在北京西山下苇甸剖面寒武系第三统和芙蓉统内识别出5种沉积相类型，并根据沉积环境将其归入3种相组合，分别形成于浅海碳酸盐缓坡潮下带、深潮下带和页岩盆地环境。在研究地层内，共识别出了49层风暴沉积，基于沉积结构和构造特征，这些风暴沉积层可归入4个风暴沉积大类（原地未破碎风暴沉积、原地破碎风暴沉积、近源风暴沉积、远源风暴沉积）和12个亚类，这些风暴沉积类型形成于不同的环境。根据风暴沉积亚类在地层中的分布规律及其所指示的环境类型，恢复了北京西山寒武纪中晚期相对海平面的变化历史。通过与用不同方法恢复的北京西山和鲁西地区同时期海平面变化曲线进行对比，发现利用风暴沉积类型所恢复的海平面变化曲线与使用正常沉积类型恢复的海平面变化曲线具有相同的变化趋势。因此，风暴沉积类型可以用于恢复长时间尺度的海平面变化趋势。
화북지구한무계중발육유대량적풍폭침적，대우차류침적물적성인전인의견추우통일，단대기침적배경적인식잉존재교다쟁의。재야외세치관찰、실측적기출상，결합실내침적학묘술화분석，재북경서산하위전부면한무계제삼통화부용통내식별출5충침적상류형，병근거침적배경장기귀입3충상조합，분별형성우천해탄산염완파조하대、심조하대화혈암분지배경。재연구지층내，공식별출료49층풍폭침적，기우침적결구화구조특정，저사풍폭침적층가귀입4개풍폭침적대류（원지미파쇄풍폭침적、원지파쇄풍폭침적、근원풍폭침적、원원풍폭침적）화12개아류，저사풍폭침적류형형성우불동적배경。근거풍폭침적아류재지층중적분포규률급기소지시적배경류형，회복료북경서산한무기중만기상대해평면적변화역사。통과여용불동방법회복적북경서산화로서지구동시기해평면변화곡선진행대비，발현이용풍폭침적류형소회복적해평면변화곡선여사용정상침적류형회복적해평면변화곡선구유상동적변화추세。인차，풍폭침적류형가이용우회복장시간척도적해평면변화추세。
Storm deposits were extensively developed in the Middle and Upper Cambrian in North China.However,the sedimentary environments of these storm deposits are a matter of debate.Based on careful observation and measurement of the Xiaweidian section in Western Hills of Beijing,North China, five lithofacies are identified,which are further grouped into three lithofacies associations that were deposi_ted in shallow subtidal zone,deep subtidal zone,and shaly basin,respectively.According to the sedi_mentary textures and structures,49 layers of storm deposits are recognized in the studied section,which are grouped into 4 types (named as:In_situ unbroken,in_situ broken,proximal,and distal storm de_posits) and 1 2 sub_types that were formed in various sedimentary environments.A new sea_level curve is inferred from the changes of storm deposit sub_types in the Middle and Upper Cambrian at western Beijing. This sea_level curve matches well with the curve reconstructed from facies analysis of fair_weather deposits in the studied section,as well as those inferred by previous researches in Beijing and in western Shandong Province,North China.Thus,types of storm deposits can be utilized to reconstruct long_term sea_level changes in the geological history.