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对四川盆地中东部茅口组进行了详细的牙形刺研究,发现丰富化石,共计3属13种。在茅口组识别出3个牙形刺带,自下至上依次为Jinogondolella altudaensis带,J.xuanhanensis带和J.granti带。上覆地层为王坡煤系的茅口组产出的最高牙形刺带为J.granti带,而峨眉山玄武岩的茅口组产出的最高牙形刺带为J.xuanhanensis带。牙形刺化石高CAI值的时间演化规律和空间分布特征与峨眉山玄武岩喷发具有良好的相关性。喷发到地表的岩浆对四川盆地热演化有极大影响,但影响时间和范围有限。峨眉山地幔柱活动对岩石圈热状态影响范围很小,在超级地幔柱的“中带”和“外带”地层中没有体现。
A detailed conodont study was conducted on the Maokou Formation in the central and eastern Sichuan Basin. A total of 13 genera and 3 genera were found abundant in fossils. In the Maokou group, three conodonts were identified, followed by Jinogondolella altudaensis, J. xuanhanensis and J.granti bands. The uppermost conodont of the Maokou Formation overlying strata was the Wangpu coal, and the highest conodont of the Maokou Formation on the Emeishan basalt was the J.xuanhanensis belt. The time evolution and spatial distribution of high CAI value of conodont fossils have a good correlation with Emeishan basalt eruption. The magma erupted to the surface greatly affected the thermal evolution in the Sichuan Basin, but its time and scope of impact were limited. The Emeishan mantle plume activity has little influence on the thermal state of the lithosphere, and is not reflected in the “mantle belt” and “belt” beds of the super mantle plume.