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对浙江西南和福建西南数个小型沉积盆地的11个剖面和观察点进行了地质调查,在中国大陆第一次识别了白垩纪中期三种古土壤类型,分别是粘土红壤、钙质土壤和铁质土壤型。粘土红壤型以发育红色(粉砂质)泥岩、生物潜穴、植物根系(根迹)为特点,钙质土壤型以发育紫灰色调钙质泥岩、钙质结核(含姜结石)为标志,铁质土壤型显示了紫红和橙黄色调泥岩、粉砂岩与铁质皮壳及结核组合。进而提出,白垩纪中期的阿普特期-阿尔布时期,在浙江西南金华—衢州—丽水盆地、中部的永康盆地大量发育钙质土壤,以横山组、中戴组、金华组、馆头组和朝川组为代表,属于亚热带干旱—半干旱气候产物;在闽西南地区出现丰富的铁质氧化型土壤,由板头组、均口组和沙县组为代表,反映热带半干旱气候;之后的白垩纪中期赛诺曼期(衢县组)在浙西局部地区气候变为亚热带温湿气候,古土壤变为粘土红壤型,开始产生较为丰富的生物活动,而闽西南主体气候格局可能不变,但沉积建造因区域构造断隆作用转变为巨厚的“丹霞”砾岩。
Geological investigations were carried out on 11 sections and observation points in southwestern Zhejiang and several small-scale sedimentary basins in southwestern Fujian Province. For the first time in mainland China, three types of paleosol were identified in the Cretaceous: clay loam, calcareous soil and iron Soil type. Clay red soil type is characterized by the development of red (silty) mudstone, biological latent sites and plant roots (root trace). The calcareous soil type is characterized by the development of limestone calcareous mudstone and calcareous nodule (including ginger stone) Irony soil type shows mauve and orange tone mudstone, siltstone and iron hull and tuberculosis combination. Furthermore, it is proposed that during the period of the A Crete Period - Albuquerca in the mid Cretaceous, calcareous soil was extensively developed in Jinhua-Quzhou-Lishui basin in southwestern Zhejiang Province and Yongkang basin in central China. The calcareous soil was abundant in the Hengshan, Zhongde, Jinhua, And the Chaochuan Formation, belong to the subtropical arid-semi-arid climatic products. Rich iron oxide-type soils are present in the southwestern Fujian Province, represented by the Panitou Formation, the Jikou Formation and the Shaxian Formation, reflecting the tropical and semi-arid climate. After that, In the mid Cretaceous, the Senengian (Quxian Formation) climate changed to subtropical climate in the part of western Zhejiang, paleosol turned into clay-red soil and began to produce abundant biological activity, while the main climate pattern in southwestern Fujian may not change , But the sedimentary structure was changed into a thick “Danxia” conglomerate due to regional tectonic disconnection.