regional_angular_unconformity

1.Field surveys and seismic exploration show that the lowest regional angular unconformity older than the Carboniferous developed between the Cretaceous and the pre-Cretaceous strata.
地表地质调查和人工地震勘探结果证实，石炭纪以来最早的区域性角度不整合发育于白垩系与前白垩纪地层之间。
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