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中生代中晚期的燕山运动在中国东南部形成一系列断陷、断拗盆地和火山洼地,其中堆积或沉积了巨厚的火山岩和河湖相碎屑沉积,浙江永康、东阳盆地白垩系馆头组(113 Ma)和朝川组(99~110 Ma)的湖相碳酸盐岩就是形成于这个时期。从岩性、沉积相和生物群特征分析,它们形成于热带雨季、旱季交替气候。早白垩世早期温暖湿润,早白垩世中、晚期向炎热干旱化演变,湖泊蒸发量逐渐大于降雨量,导致湖水中溶解的陆源碎屑碳酸盐浓度不断增加,析出沉淀,形成大量钙质结核乃至大小不一的泥晶灰岩透镜体,到朝川组沉积后期,随着气候更加干旱炎热,湖盆碳酸盐沉积除了在紫红色碎屑岩中形成更多的钙质结核和泥晶灰岩透镜体外,还形成了薄层—中层状泥晶灰岩夹层。
The Yanshan movement in the middle and late Mesozoic formed a series of fault depression, atrophy bend and volcanic depressions in southeastern China. Thick volcanic rocks and fluvial lacustrine clastic sediments were deposited or deposited. Cretaceous Guantou Formation in Yongkang and Dongyang basins of Zhejiang Province (113 Ma) and Chaochuan Formation (99 ~ 110 Ma) lacustrine carbonate rocks formed during this period. From lithology, sedimentary facies and biome characterization, they formed in the tropical rainy season, alternating climate during the dry season. Early Early Cretaceous warm and humid early Cretaceous evolution to the hot and dry, the lake evaporation is gradually greater than the rainfall, resulting in lake water dissolved terrestrial carbonate concentrations continue to precipitate precipitation to form a large number of calcium tuberculosis Even to the late Chuanchuan Formation sediments, with the more arid and hot climate, the carbonate deposition in the lake not only formed more calcareous nodules and smectite gray in the purple clastic rocks In addition, the rock lens formed a thin layer of medium-sized limestone interlayer.