摘要
为了揭示华北盆地晚石炭世冰室期海平面变化的驱动机制,以盆地东北缘的柳江煤田本溪组—太原组为对象,进行了海平面变化恢复及其与同时代高纬度冈瓦纳大陆冰期—间冰期(冰川)旋回联系的研究。结果表明:(1)研究区目标地层发育海岸平原河流—湖泊、滨海和浅海3种相组合,沉积环境变化记录了2个二级海侵—海退旋回(巴什基尔—中莫斯科期和晚莫斯科—早阿瑟尔期)和4个三级海侵—海退旋回(早巴什基尔期、中巴什基尔—早莫斯科期、晚莫斯科期、晚莫斯科—阿瑟尔期)。(2)冰室期的冰期和间冰期分别与研究区二级相对高海平面和低海平面时期的良好对应关系说明,高纬度冰川旋回是晚石炭世华北盆地二级海平面变化的主控因素。(3)煤—富有机质泥岩和铝土岩在冰期发育,指示冰期下降的海平面和降低的温度,有利于陆表海盆地沉积界面暴露、沼泽化,以及有机质的产生和保存。同时,冰期海平面下降还引起干湿交替的泛滥平原环境的盛行。在该环境中,陆源碎屑沉积物经过再风化和淋滤,促进了铝土质泥岩或铝土矿的形成。本次研究深化了对晚石炭世华北盆地海平面变化驱动机制、煤和铝土矿等沉积矿产聚集规律的认识。
In order to reveal the driving mechanism of sea level changes in the North China Basin in the low latitudes of the Late Carboniferous.Taking Benxi-Taiyuan Formations in Liujiang Coalfield of North China Basin as an example,the restoration of sea level change in low latitude area and its relationship with glacier cycle in high latitude area are studied.The results show that:(1)Three sedimentary systems of coastal plain river-lake,littoral zone and shallow sea are identified in the target strata of the study area.The changes of sedimentary environment record two secondorder transgression-regression cycles(Bashkir-Middle Moscow period and Late Moscow-Early Assel period)and four third-order transgression-regression cycles(Early Bashkir period,Middle Bashkir-Early Moscow period,Late Moscow period and Late Moscow-Assel period).(2)The highlatitude glacial and interglacial periods correspond to the second-order relative high sea level and low sea level periods in the study area,respectively,indicating that the high-latitude glacial cycle is the main controlling factor of the second-order sea level change in the late Carboniferous low-latitude North China Basin.(3)The coal-organic-rich mudstone and bauxite developed during the glacial period,indicating the falling sea level and temperature during the glacial period,which is conducive to the exposure of sedimentary interfaces,swamping,and the generation and preservation of organicmatter in the epicontinental sea basin.At the same time,the decline of sea level during the glacial period also caused the prevalence of dry-wet alternate flood plain environment.In this environment,terrigenous clastic sediments are reweathered and leached,which promotes the formation of bauxite mudstone or bauxite.This study deepens our understanding of the driving mechanism of sea level change and the accumulation of sedimentary minerals such as coal and bauxite in the late Carboniferous North China Basin.
作者
孟晶
刘昊青
杨敏芳
王雷
胡晓玉
王野
周凯
邵龙义
鲁静
MENG Jing;LIU Haoqing;YANG Minfang;WANG Lei;HU Xiaoyu;WANG Ye;ZHOU Kai;SHAO Longyi;LU Jing(Management Center of Liujiang Basin Geological Relics National Nature Reserve,Hebei Qinhuangdao 066000,China;National Key Laboratory of Fine Exploration and Intelligent Development of Coal Resources,College of Geoscience and Surveying Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;Petroleum Exploration and Development Research Institute,PetroChina,Beijing 100083,China;PetroChina Coalbed Methane Company Limited,Beijing 100028,China;College of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China)
出处
《古地理学报》
北大核心
2026年第1期304-317,共14页
Journal of Palaeogeography:Chinese Edition
基金
国家重点研发计划项目(编号:2022YFF0800200)
国家自然科学基金项目(编号:42172196,42472227,42402179)
河北柳江盆地地质遗迹保护项目(编号:Z1303002403442001)联合资助成果。
关键词
晚石炭世
华北盆地
海平面变化
冰川旋回
煤和铝土矿
Late Carboniferous
North China Basin
sea level change
glacier cycle
coal and bauxite
