摘要
江山-绍兴断裂带是中国南方最重要的构造带之一,它是扬子陆块东段一江南陆块与华夏陆块北缘的碰撞拼贴带.其不同期的活动反映了不同的构造环境,具有不同的构造变形特征,并直接控制了两侧的地质演化历史.
Jiangshan-Shaoxing Fracture zone is one of the most important zones in southern China.It is a collision zone between Jiangnan landmass and Cathaysia landmass. It's movements in different stages represented different tectonic environments and exhibited deformational features, and directly controlled geological evolution history of both sides,Strong collision and compression during Shenggong movement (at the end of Mesoproterozoic) resulted Shuangxiwu group into strong tectonic deformation to form recumbents or reclined folds with the axial direction closing to E-W,and the Western,Zhejiang Foreland Basin was formed. During Jinning movement (at the early of Late Proterozoic),the two landmasses continued to bolique collision with magma intrusion.It made the collision zone more consolidated,moreover sinistral shear caused that Western Zhejiang Compressional Foreland Basin was changed into Western Zhejiang Tensional Downwarped Basin.Owing to the change from tensional downwrap to collisional compression between Cathaysia landmass and Yangtze landmass during Caledonian stage,Jiangshan-Shaoxing collision zone shown as a ductile shear zone, and the shearing direction was changed from sinistral to dextral strike slip. During Indosinian movement,Cathaysia landmass ocurred large scale napping toward north,not only it made all sediment in Western Zhejiang Foreland Basin and Downwraped Basin strong folding,but also a series of thrust-nappe structure was formed and caused Pre-sinian formation thrust onto late strata along Jiangshan-Shaoxing collision zone.During Yanshanian stage,The crust of coastal region of southeastern China came into evolutional stage of continental margin.Block faulting controlled deelopment of Meso-cenozoic sediment-volcanic basins.In south side of the collision zone a large scale Mesozoic volcanic rock developed,but in north side only a few sediment-volcanic basin developed.Along Jiangshan-Shaoxing collision zone there were Meso-cenozoic fault subsidence basins showing a string of beads.
基金
浙江省自然科学基金
关键词
构造演化
变形特征
陆块
碰撞带
断裂带
tectonic evolution
deformational features
jiangnan landmass
cathaysia landmass
Jiangshan-Shaoxing collision zone