Architecture of deepwater turbidite lobes: A case study of Carboniferous turbidite outcrop in the Clare Basin, Ireland

• 作者: ZHANG Leifu LI Yilong
• 来源期刊: 石油勘探与开发:英文版
• 学科: 地球科学
• 关键词: deepwater sedimentation turbidite lobes outcrop anatomy architecture hierarchy quantitative characterization Carboniferous Ross Sandstone Formation IRELAND
• 年，卷（期）: 2020,（5）
• 页码范围: 990-1000
• 页数: 11页
• 分类号: P618.13

摘要

Through lithofacies analysis and architecture anatomy of the Carboniferous Ross Sandstone turbidites outcropped at western Ireland,the depositional model of deepwater turbidite lobes is established.Seven types of lithofacies are recognized including goniatites-rich shale,laminated shale,laminated siltstone,massive sandstone,fine-medium sandstone with mud-clast,basal gravel,and chaotic mudstone,which can be subdivided into units of three origins,turbidite lobe,turbidite channel,and slide-slump;and four hierarchical levels,lobe complex,lobe,lobe element and single sandstone layer.The lobes show apparent compensational stacking pattern,lobe elements display typical thickening-upward cycles on vertical profile,and the higher the hierarchical level,the better the preservation of the hierarchical boundary is.In general,turbidite lobe deposits appear as tabular,parallel/sub-parallel sandstone and mudstone interbeds,and change from thick,massive sandstone in the proximal end to thinner sandstone and mudstone interbeds from axis to fringe,with the sand-shale ratio and degree of sandstone amalgamation decreasing.