沉积与特提斯地质2024，Vol.44Issue(4)：840-853,14.DOI:10.19826/j.cnki.1009-3850.2023.12003
四川盐源地区名胜剖面志留系龙马溪组黑色泥页岩地球化学特征及物源构造背景分析
Analysis of geochemical characteristics,provenance,and tectonic background of black shale in the Silurian Longmaxi Formation of the Mingsheng section in the Yanyuan area,Sichuan Province
摘要
Abstract
The graptolitic shales of the Longmaxi Formation were widely deposited during the Silurian transition in the Yanyuan area.This study selected fresh outcrops of the Silurian Longmaxi Formation at the Mingsheng section in the Yanyuan area,systematically sampled them,and analyzed the vertical variation characteristics of major,trace,and rare earth elements in the section.Moreover,this study discussed the perspective of geochemical characteristics,provenance characteristics,and tectonic environment of that period.Research results show that the Longmaxi Formation at the Mingsheng section in the Yanyuan area is predominantly siliciclastic shale facies(sections L1,L3,and L4),with higher carbonate mineral content in sections L2 and L5,and brittle minerals such as quartz and feldspar are less abundant in sections L2 and L5,while clay minerals show a significant increasing trend from bottom to top.The sediments of the Longmaxi Formation at the Mingsheng section have a dual source of mafic and felsic materials:sections L3 and L4 are of mafic or ultramafic provenance,while sections L1,L2,and L5 are more felsic or a mixture of felsic and mafic sources.The tectonic background of the source rock formation is continental margin,and the sediments exhibit dual characteristics of both active and passive continental margins.The variation in provenance indicates that the composition of the Kangdian paleocontinent was complex in the Early Silurian.关键词
名胜剖面/志留系/龙马溪组/泥页岩/物源特征/构造背景Key words
Mingsheng section/Silurian/Longmaxi Formation/shale/provenance/tectonic setting分类
天文与地球科学引用本文复制引用
程锦翔,邓敏,杨贵来,余谦..四川盐源地区名胜剖面志留系龙马溪组黑色泥页岩地球化学特征及物源构造背景分析[J].沉积与特提斯地质,2024,44(4):840-853,14.基金项目
中国地质调查局项目"四川盆地东南缘煤层(系)气调查评价"(DD20242049),"四川盆地及周缘页岩气地质调查与评价"(DD20240046),"四川盆地油气资源潜力评价"(DD20242405),"自然资源部深时地理环境重建与应用重点实验室开放基金"(DGERA20231107) （系）
