煤田地质与勘探2025，Vol.53Issue(2)：13-21,9.DOI:10.12363/issn.1001-1986.24.09.0597
华北盆地大陆化学风化趋势与晚石炭世-早二叠世高纬度冰川旋回的联系
Relationship between continental chemical weathering trends in the North China Basin and the high-latitude glacial cycles from the Late Carboniferous to the Early Permian
摘要
Abstract
[Objective and Methods]The Late Paleozoic Ice Age(LPIA;ca.360‒254 Ma),the only period recording the transition from icehouse to greenhouse conditions throughout the geological history,can provide a deep-time perspect-ive for glacier-environment-climate coevolution and future climate change.To gain a deep understanding of the poten-tial relationship between the continental chemical weathering trends in low-latitude regions and the glacial cycles in the high-latitude Gondwana region from the Late Carboniferous to the Early Permian,this study investigated the mudstones of the Benxi-Taiyuan formations,Liujiang coalfield,North China Basin.Using multiple chemical weathering indices such as chemical index of alteration(CIA),chemical index of weathering(CIW),and plagioclase index of alteration(PIA)calculated from the elemental geochemical data of the mudstones,this study reconstructed the continental chemic-al weathering trends and paleoclimatic evolutionary characteristics of the Liujiang coalfield.[Results]The results indic-ate that the periodic changes of continental chemical weathering in the low-latitude Liujiang coalfield involved three weathering weakening stages(i.e.,early-middle Bashkirian,Moscovian-Kasimovian,and early Asselian)and two weath-ering enhancement stages(i.e.,late Bashkirian and Gzhelian).This cyclic alternation of weathering trends was closely associated with the glacial cycles of the high-latitude Gondwanaland.The weathering weakening stages represent shifts to relatively cool and dry climates,roughly synchronous with the glacial periods at high latitudes.In contrast,the weath-ering enhancement stages suggest changes to relatively warm and humid climates,coinciding with the interglacial peri-ods at high latitudes.The comparative analysis reveals that frequent volcanic activity,increased atmospheric CO2 con-centration,climate warming,enhanced hydrologic cycles,and sea-level rise during the interglacial periods jointly con-tributed to the reduced area of tropical rainforests and the enhanced continental chemical weathering,creating favorable conditions for the formation of bauxite.In contrast,the weakening volcanic activity,cooling climate,reduced atmospher-ic CO2 concentration,and increased rainforest area during the glacial periods led to weakened continental weathering,fa-cilitating the formation of coals and organic-rich mudstones.[Conclusions]The results of this study reveal the relation-ship between the continental chemical weathering trends in the low-latitude North China Basin and the glacial cycles and the distributions of sedimentary minerals(e.g.,coals and bauxite)in the high-latitude Gondwana region,providing a novel perspective for understanding the mechanisms underlying complex glacier-environment-climate interactions throughout the geological history.关键词
晚古生代/华北盆地/化学风化/CIA/冰期/间冰期Key words
Late Paleozoic Era/North China Basin/chemical weathering/chemical index of alteration(CIA)/glacial period/interglacial period分类
地质学引用本文复制引用
凌紫玉,杨敏芳,王雷,王野,张培新,刘昊青,邵龙义,鲁静..华北盆地大陆化学风化趋势与晚石炭世-早二叠世高纬度冰川旋回的联系[J].煤田地质与勘探,2025,53(2):13-21,9.基金项目
国家重点研发计划课题(2022YFF0800203) （2022YFF0800203）
国家自然科学基金项目(42172196,42472227,42402179) （42172196,42472227,42402179）
河北柳江盆地地质遗迹保护项目(Z1303002403442001) （Z1303002403442001）
