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６０ ｍ 水深附近的灰色鲕粒（０．０５～０．１２５ ｍ ｍ 粒级），１１０ ｍ 水深附近的白色鲕粒（０．１２５～０．０６２ ５ ｍｍ 粒级）和９０ ｍ 水深附近内的浅褐色球状粒（０．１２５～０．０６２ ５ ｍ ｍ 粒级）均产自卡奇湾外的大陆架上。在横切面上，观察到灰色鲕粒有５ 个同心生长环，白色鲕粒有３ 个同心生长环。灰色鲕粒中，电子探针研究发现的含Ｆｅ 和Ｓ的内部黑色生长环被认为是海退之后黄铁矿化作用的结果。白色鲕粒未显示有任何元素变化。球状粒含有有机物。由此得出下述推论：（１）灰色鲕粒比白色鲕粒老，尽管它们均产自浅水区域；（２）全新世时期在６０ ｍ 水深附近内发生的几次海平面反转导致其形成和鲕粒的黄铁矿化作用。
(0,05 to 0,125 m m grain size) near the water depth of 60 m, white oolites (0.125 to 0.062 5 mm grain size) near the water depth of 110 m and water depths in the vicinity of 90 m water depth The beige globular grains (0.125-0.062 5 m m) were all produced on the continental shelf outside of Catch Bay. On the cross section, five concentric growth rings were observed for gray ooids and three concentric rings for white ooids. Among the gray ooids, the internal black growth rings containing Fe and S, which were discovered by electron probe studies, were considered to be the result of pyritization after the regression. White ooids did not show any elemental changes. Globules contain organic matter. The following conclusions are drawn: (1) gray ooids are older than white ooids, even though they both originate from shallow waters; (2) several sea-level reversals during the Holocene near 60 m water depth led to Formation and pyritization of ooids.