Ordovician and Triassic shoals on the edge of platform distribute widely in the Lower-Middle reaches of the Yangtze River, while the shoals of Sinian and Cambrian are relatively few. The shoal in the Jurong County, Jiangsu province, is the largest one in this area with a thickness of 206 meters. Patch shoals distribute mainly in the underwater uplift in the open platform. Sometimes they can also be found in restricted platforms, commonly showing small lens-like in shape. The vertical factes of patch shoals change rapidly and commonly develop into restricted or open platform factes. The patch shoals distribute mainly in the Cambrian system in Hubei, Hunan Province and the Carboniferous system in Hubei, Jiangsu, Anhui province. The shoal factes rocks consist chiefly of the single grain rock of cold, oncoid, lump, intraclast as small as sand, bioclast or the multiple grain rocks. The shoal on the edge of platform is composed of grain sparite limestone while the patch shoal is dominated by micritic-sparite and micritic grain limestone. Ordovician and Triassic shoals on the edge of platform distribute widely in the Lower-Middle reaches of the Yangtze River, while the shoals of Sinian and Cambrian are relatively few. The shoal in the Jurong County, Jiangsu province, is the largest one in this area with a thickness of 206 meters. Patch shoals distribute mainly in the underwater uplift in the open platform. Sometimes they can also be found in restricted platforms, commonly showing small lens-like in shape. into restricted or open platform factes. The shoal factes rocks consists chiefly of the Cambrian system in Hubei, Hunan Province and the Carboniferous system in Hubei, Jiangsu, Anhui province. The shoal factes rocks consists chiefly of the single grain rock of cold, oncoid, lump , intraclast as small as sand, bioclast or the multiple grain rocks. The shoal on the edge of platform is composed of grain sparite limestone while the patch shoal is dominated by micritic-sparite and micritic grain limestone.