Four isolate barrier beds occurened usually in boundary surface of each internal architecture unit in channel sandbody, i. e. find bed, muddy pebble bed, plant clasts bed and diagenic bed.

在道砂体内部构成的不同次实体界面，通常存在着4种隔挡，即细粒物质隔挡、隔挡、植物碎屑隔挡和成岩隔挡。